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What is anesthesia? What are the types of anesthesia? What is General Anesthesia? What is spinal and epidural anesthesia? What determines the type of anesthesia used? What are the potential risks and complications of anesthesia? How should you prepare for anesthesia? What happens when you are recovering from anesthesia? What is a general anesthetic? What are the side effects and possible complications? What is a spinal anesthetic? What are the side effects and possible complications? What is an epidural anesthetic? What are the side effects and possible complications? What is a local anesthetic? What are the side effects and possible complications? What are the risks of anesthesia? What are some side effects of anesthesia? What is an anesthesiologist? What about premedication? What are the complications of anesthesia? What happens when you are recovering from anesthesia? What are the indications of endotracheal intubation? How do we do endotracheal intubation? How do we verify that the endotracheal tube is in right place? When do we extubate? How do we extubate? What are the contraindications of endotracheal intubation? How does general anesthetia work? What essential resources are required to induce general anesthesia? How would you induce general anesthesia? What is the volume and dose? Why do we need to do endotracheal intubation during general anesthesia? Does every ventilated patient need to be intubated? Does every intubated patient need to be ventilated? What are the indications for mechanical ventilation in different clinical situations? How do we test the effectiveness of a mechanical ventilator prior to mechanical ventilation? How do we test the effectiveness of a mechanical ventilator during mechanical ventilation? What are the contraindications to mechanical ventilation? When do we need to wean the patient from mechanical ventilation? How do we wean the patient from mechanical ventilation? What are neuromuscular blocking agents? Why are neuromuscular blocking agents used? How will the patient look or feel on neuromuscular blocking agents? How is the level of relaxation being monitored? What are the side effects of neuromuscular blocking agents?
What is anesthesia? Anesthesia controls pain during surgery or other medical procedures. It includes using medicines, and sometimes close monitoring, to keep you comfortable. It can also help control breathing, blood pressure, blood flow, and heart rate and rhythm, when needed. An anesthesiologist or a nurse anesthetist takes charge of your comfort and safety during surgery. This topic focuses on anesthesia care that you get from these specialists. Anesthesia may be used to: * Relax you. * Block pain. * Make you sleepy or forgetful. * Make you unconscious for your surgery. Other medicines also may be used to relax your muscles during surgery. What are the types of anesthesia? * Local anesthesia numbs a small part of the body. You get a shot of local anesthetic directly into the surgical area to block pain. It is used only for minor procedures. You may stay awake during the procedure, or you may get medicine to help you relax or sleep. * Regional anesthesia blocks pain to a larger part of your body. Anesthetic is injected around major nerves or the spinal cord. You may get medicine to help you relax or sleep. Major types of regional anesthesia include: o Peripheral nerve blocks. A nerve block is a shot of anesthetic near a specific nerve or group of nerves. It blocks pain in the part of the body supplied by the nerve. Nerve blocks are most often used for procedures on the hands, arms, feet, legs, or face. o Epidural and spinal anesthesia. This is a shot of anesthetic near the spinal cord and the nerves that connect to it. It blocks pain from an entire region of the body, such as the belly, hips, or legs. * General anesthesia affects the brain as well as the entire body. You may get it through a vein (intravenously), or you may breathe it in. With general anesthesia, you are completely unaware and do not feel pain during the surgery. General anesthesia also often causes you to forget the surgery and the time right after it. What is General Anesthesia? General anesthesia is a reversible state of unconsciousness and insensibility to pain. It can well be described as a reversible state of oblivion. Regional anesthesia is when an injection of local anesthetic is used to anesthetize specific nerves leading to regions of the body. Examples of this include an injection into the brachial plexus to render the arm numb, an injection into the cerebrospinal fluid to anesthetize the lower limbs, etc. Local anesthesia is used to describe an injection of local anesthetic around an area, without blocking specific nerve trunks. An example of this would be an injection in the skin to numb it before suturing up a cut. What determines the type of anesthesia used? The type of anesthesia used depends on several things: * Your past and current health. The doctor or nurse will consider other surgeries you have had and any health problems you have, such as heart disease, lung disease, or diabetes. You also will be asked whether you or any family members have had an allergic reaction to any anesthetics or medicines. * The reason for your surgery and the type of surgery. * The results of tests, such as blood tests or an electrocardiogram (EKG, ECG). Your doctor or nurse may prefer one type of anesthesia over another for your surgery. In some cases, your doctor or nurse may let you choose which type to have. Sometimes, such as in an emergency, you do not get to choose. What are the potential risks and complications of anesthesia? Major side effects and other problems of anesthesia are not common, especially in people who are in good health overall. But all anesthesia has some risk. Your specific risks depend on the type of anesthesia you get, your health, and how you respond to the medicines used. Some health problems increase your chances of problems from anesthesia. Your doctor or nurse will identify any health problems you have that could affect your care. Your doctor or nurse will closely watch your vital signs, such as your blood pressure and heart rate, during anesthesia and surgery, so most side effects and problems can be avoided. How should you prepare for anesthesia? Make sure you get a list of instructions to help you prepare for your surgery. Your surgeon will also let you know what will happen when you get to the clinic or hospital, during surgery, and afterward. Your doctor will tell you when to stop eating and drinking before your surgery. When you stop depends on your health problem and the type of anesthesia that will be used. If you take any medicines regularly, ask your doctor or nurse if you should take your medicines on the day before or the day of your surgery. You have to give your consent to be given anesthesia. Your doctor or nurse will discuss the best type of anesthesia for you and review risks, benefits, and other choices. Many people are nervous before they have anesthesia and surgery. Mental relaxation methods as well as medicines can help you relax. What happens when you are recovering from anesthesia? Right after surgery you will be taken to the recovery room. Nurses will care for you there under the direction of an anesthesiologist. A nurse will check your vital signs and any bandages and ask about how much pain you have. If you are in pain, don't be afraid to say so. Some effects of anesthesia may last for many hours after surgery. If you had local or regional anesthesia, you may have some numbness or reduced feeling in part of your body. Your muscle control and coordination may also be affected. Other common side effects of anesthesia are closely watched and managed to reduce your discomfort. These side effects include: * Nausea and vomiting. In most cases, this can be treated and does not last long. * A mild drop in body temperature. You may feel cold and may shiver when you first wake up. For minor surgeries, you may go home the same day. For more complicated surgeries, you may have to move to a hospital room to continue your recovery. If you stay in the hospital, your doctor or nurse will visit you to check on your recovery from anesthesia and answer any questions you have. What is a general anesthetic? What are the side effects and possible complications? A general anesthetic usually starts with the IV injection of a medication that causes rapid loss of consciousness. Occasionally, anesthesia starts with the use of an inhaled anesthetic gas. This is usually easier and more comfortable for children. After the anesthetic has started, the anesthesiologist will use a combination of IV medications and anesthetic gases to keep you asleep during surgery. The anesthetic gas is turned off at the end of surgery when its time to wake up. Frequently, patients feel only moments have gone by when in reality, several hours may have passed. What is a spinal anesthetic? What are the side effects and possible complications? A spinal anesthetic is an injection of medication in the lower part of the back. The medication is injected by a very small needle into the spinal fluid where it spreads out to numb the nerves that go to the lower half of your body. You may feel a tingling sensation or warmth spread over your legs as the medication begins to work. However, most people wont feel any unusual sensations, but will notice that it is impossible to move their legs when the spinal anesthetic is working. Your anesthesiologist may test the level of anesthesia a few minutes after the injection to make sure it is working well. Many patients want to know if the spinal injection hurts. In general, the spinal anesthetic is no more painful than having an IV started. Usually an injection of local anesthetic is given at the skin level so that the placement of the spinal needle is not felt. Occasionally, you may feel an electric sensation down one leg let the anesthesiologist know immediately so he or she may adjust the angle of the needle to make it more comfortable for you. The spinal injection may be difficult due to anatomic abnormalities such as scoliosis or unusual bone formation around the vertebra in the lower back. Your anesthesiologist may ask you to curl up and push you lower back out toward them. This straightens your back and increases the size of the small openings the spinal needle must go through. If you feel anxious about the spinal injection, your anesthesiologist may give you a sedative to help you relax. Its best not to have you fully unconscious during the spinal injection since your anesthesiologist will probably need your assistance with positioning. Side effects of spinal anesthesia are uncommon, but the following are seen most often: 1. Spinal headache: Approximately 1% of patients will develop a headache within 24 hours after the spinal anesthetic. The cause of the headache is a slow leak of spinal fluid out the hole left by the needle. Changes in the shape and size of the needle have greatly reduced the incidence of this problem. Although a spinal headache is not life threatening, it can be quite uncomfortable. It is almost always more painful in the sitting or standing position than lying down. For many years, it was assumed that lying flat for 24 hours after a spinal injection would reduce the risk of spinal headache. We know now that position does not increase the risk. The headache will resolve spontaneously but this may take weeks. If the headache is mild, it may resolve quickly by drinking more fluids and taking caffeine. If the headache is severe and incapacitating, an alternative treatment is the "blood patch", which can usually resolve the headache within an hour. The blood patch is about 99% effective in relieving the headache, but often causes a pressure feeling in the lower back for a day. Serious complications from the blood patch are very rare and include infection or irritation of spinal nerves. 2. Difficulty urinating after the spinal anesthetic. Even when the spinal anesthetic appears completely resolved, it may be difficult to urinate for up to 24 hours. This problem is most common with older men (especially with prostate enlargement). If a bladder catheter is planned for surgery and postoperative care, difficulty urinating is not an issue. However, inability to urinate may delay your discharge from the hospital for "same day" surgeries. 3. Low blood pressure. A spinal anesthetic normally lowers blood pressure about 10 to 20 percent, and blood pressure returns to normal when the spinal anesthetic resolves. Occasionally, blood pressure falls more that expected, but can be treated quickly with IV fluids and medication. Low blood pressure may make some feel dizzy and nauseated. On some occasions the blood pressure may be slow to return to normal even after the spinal anesthetic has resolved. These patients are kept in the recovery room and treated until their blood pressure has returned to a normal range. Certain blood pressure medications are more likely to increase the possibility of these problems. Thankfully, serious complications of spinal anesthesia are very rare. The possible complications include infection, nerve damage, and death. Although many people fear nerve damage from a spinal anesthetic, the incidence of nerve injury from a spinal anesthetic is no greater than the incidence of nerve injury from general anesthesia. What is an epidural anesthetic? What are the side effects and possible complications? An epidural anesthetic is very similar to a spinal anesthetic except the epidural needle does not puncture the sac that holds the spinal fluid. Instead, a tiny tube or catheter is inserted through the needle and comes to rest just outside the sac. Numbing medication is given through this tube that gradually gets absorbed through the sac and into the spinal fluid. The epidural anesthetic therefore takes longer to provide pain relief.. The benefit of an epidural anesthetic is that it can last much longer than a spinal anesthetic by leaving the soft epidural catheter in place and continually giving medication. This flexibility is what makes epidural anesthesia the choice for relief of pain during labor. Many times the epidural catheter is left in place after surgery in order to give medication through the tube to help manage postoperative pain. Many patients ask if the placement of the epidural catheter is painful. In general, the placement of an epidural catheter is no more painful than placement of an IV catheter. Usually an injection of local anesthetic is given at the skin level so that the placement of the epidural needle is not felt. Occasionally, you may feel an electric sensation down one leg let the anesthesiologist know immediately so he or she may adjust the angle of the needle to make it more comfortable for you. Epidural placement may be difficult due to anatomic abnormalities such as scoliosis or unusual bone formation around the vertebra. Your anesthesiologist may ask you to curl up and push you lower back out toward them. This straightens your back and increases the size of the small openings the epidural needle must go through. If you feel anxious about the epidural, your anesthesiologist may give you a sedative to help you relax while the epidural is being placed. Its best not to have you fully unconscious during the epidural placement since your anesthesiologist will probably need your assistance with positioning. Possible complications from epidurals are very similar to those from spinal anesthetic (see question 7). Side effects can also occur when the catheter does not end up in the correct position. Epidural catheters are placed by feel so even a very experienced anesthesiologist cannot know exactly where the end of the catheter lays. When the anesthesiologist places an epidural, they will give a small amount of medication called a "test dose" to help them determine the position of the catheter tip. If the catheter is not is the correct position, the catheter is usually removed and replaced. Sometimes the catheter can end up in a place where the numbing medicine cannot get into the spinal fluid sac and the epidural fails to work or makes only a few nerves numb. Occasionally the catheter ends up in a blood vessel and the numbing medicine gets into the blood circulation. If the epidural is in a blood vessel, you would experience dizziness, ringing in the ears and /or an increase in heart rate when the "test dose" is given. If the epidural needle or catheter ends up puncturing the spinal fluid sac, a spinal headache is possible and treatment is the same as for spinal headache. The administration of numbing medication intended for an epidural but given directly into the spinal fluid may result in the rapid onset of a high spinal anesthetic, a sharp drop in blood pressure and difficulty breathing. Again the small "test dose" helps the anesthesiologist determine the location of the catheter tip and usually prevents these problems from occurring. Other major complications from an epidural anesthetic are extremely rare and include infection, bleeding, seizures, nerve damage and death. Although many people fear nerve damage from epidural anesthesia, the incidence of nerve damage from epidurals is no greater than the incidence of nerve damage during a general anesthetic. What is a local anesthetic? What are the side effects and possible complications? During a local anesthetic, a numbing medicine is injected around the surgical area. This injection may be done either by the surgeon or the anesthesiologist. Often, the anesthesiologist will give a sedative prior to the injection to make the procedure more comfortable for you. Many times the sedative causes a brief lapse of memory, and you may feel as though you have been asleep for part or all of the surgery. There may be moments during the surgery when you feel a pressure sensation where the surgeon is working. The anesthesiologist will be with you the entire surgery. Let them know if anything feels uncomfortable and they will make you more comfortable. The benefit of local anesthesia is that there are very few side effects or complications, and recovery time is usually faster than for other types of anesthesia. If the sedation becomes very heavy, the possible complications are similar to those of a general anesthetic. If a large amount of local anesthetic gets into the blood circulation, you may feel dizziness, ringing in your ears, and/or an increase in heart rate. Very rarely, a seizure may occur. What are the risks of anesthesia? With the extensive knowledge and training of anesthesiologists and sophisticated monitoring equipment, anesthesia is safer today than ever. Serious and potentially fatal complications are now very rare. However, the specific risks depend on the type of surgery and overall health of the patient. You should discuss with your anesthesiologist any questions you have about your specific risks. What are some side effects of anesthesia? The most common side effects are sore throat, nausea and headache. Children are often disoriented and may be temporarily delirious in the recovery room when they wake up. With spinal and epidural anesthetics, temporary difficulty with urination is common. Some pain medications may cause itching and nausea. These are common and temporary conditions. What are my possible options for pain relief during labor and delivery? http://www.spineuniverse.com/displayarticle.php/article455.html What is an anesthesiologist? An anesthesiologist is a physician who, after completing medical school, has undertaken an additional four years of postgraduate training in order to become an anesthesiologist. The American Board of Anesthesiology offers board certification for anesthesiologists. What is a nurse anesthetist? A nurse anesthetist is a registered nurse who has undertaken two years of additional training in anesthesia and has passed a certification examination. How is anesthesia practiced in the USA? (Do you have better answer) What is The World Federation of Societies of Anaesthesiologists? (Official response awaited) Do I need to see an anesthesiologist prior to my admission for surgery? Most practices will conduct preoperative assessments of all patients prior to surgery. Do I need to fast before surgery? It is generally considered preferable to have no food or drink (including water) for at least six hours prior to surgery. This is so that the stomach will most likely be empty during the anesthetic. This reduces the risk of patient vomiting during surgery and having postoperative nausea and/or vomiting. I am taking medications. Should I continue to take them prior to surgery? This obviously depends on what medications you are taking! Generally, most medications are continued right up to the time of surgery. One exception is the group of drugs that interfere with blood coagulation. Diabetic patients also require specific management strategies for surgery. If you are taking medications, you should consult with your anesthesiologist prior to surgery and find out which medications should be continued and which should be discontinued. An exception to the above comment about not eating and drinking prior to surgery is that it is normally considered acceptable to take your morning medications with a sip of water prior to coming into hospital for surgery. What about premedication? Over the last few years, anesthetic practice has changed somewhat, in that patients are not routinely receiving sedative premedication. If you are particularly anxious, discuss this in advance with your anesthesiologist and arrangements can normally be made to administer a drug such as versed (Midazolam) which will help calm your nerves prior to surgery. Often, anesthesiologists will administer versed just before you go to the operating room. What will happen to me in the operating room? In the preoperative area, it is normal to start an IV. In the operating room, you will be connected to all of the anesthesia monitors (electrocardiogram, blood pressure monitor, pulse oximeter, neuromuscular transmission monitor and maybe a BIS monitor). You will normally be given oxygen to breathe through a mask and generally, anesthesia is induced with an intravenous induction agent. What drugs are used to administer an anesthetic? A balanced anesthetic consists of several different agents. Generally, anesthesia is induced with a short-acting intravenous anesthetic such as propofol or thiopental. These drugs have a duration of action of about five minutes. After the intravenous induction, a neuromuscular blocking agent is normally used to decrease the function of the muscles of breathing. An endotracheal tube is then placed in the trachea. Anesthesia is normally maintained with a mixture of a volatile anesthetic (administered from the anesthetic machine via the endotracheal tube) as well as nitrous oxide and oxygen. A very potent opioid such as fentanyl is commonly used, as are neuromuscular blocking agents. Anesthesia is the process by which a patient is rendered able to undergo surgery. Surgery was, of course, commonly performed before any means was available to spare the patient any part of the experience. It takes little imagination to realize that an unanesthetized person enduring a surgical wound exhibits the following: * Evasive action * Severe pain and emotional distress * Maximum tension in skeletal muscles * Massive increase in sympathetic tone causing sweating, tachycardia, and hypertension * Vivid and unpleasant memory of the event forever The goals of anesthesia thus include the following: * Anesthesia (lack of awareness of surrounding events) * Akinesia (keeping the patient still to allow surgery to take place) * Muscle relaxation (to enable access through muscles to bones and body cavities) * Autonomic control (to prevent dangerous surgesin hemodynamics) General anesthesia General anesthesia uses drugs administered systemically to render the patient unaware of anything that is being done to or around him or her. It must be safe, not threatening or unpleasant to the patient, allow adequate surgical access to the operative site, and cause as little disturbance as possible to internal homeostatic mechanisms. A point worth noting is that general anesthesia, as opposed to local or regional anesthesia, may not always be the best choice. The anesthesiologist selects the optimal technique for any given patient and procedure. Attributes of general anesthesia include the following: * Advantages o Makes no psychological demand of the patient o Allows complete stillness for prolonged periods of time o Facilitates complete control of the airway, breathing, and circulation o Permits surgery to take place in widely separated areas of the body at the same time o Can be used in cases of sensitivity to local anesthetic agent o Can be administered without moving the patient from the supine position o Can be adapted easily to procedures of unpredictable duration or extent o Usually can be administered rapidly * Disadvantages o Requires the involvement of an extra set of healthcare providers o Requires complex and costly machinery o Requires some degree of preoperative patient preparation o Usually associated with some degree of physiological trespass o Carries the risk of major complications including death, myocardial infarction, and stroke o Associated with less serious complications such as nausea or vomiting, sore throat, headache, shivering, and delayed return to normal mental functioning o Associated with malignant hyperthermia, a rare, inherited muscular condition in which exposure to some (but not all) general anesthetic agents results in acute and potentially lethal temperature rise, hypercarbia, metabolic acidosis, and hyperkalemia A given patient's risk for complications as a direct result of general anesthesia is small but depends largely on his or her medical comorbidities. Death attributable to anesthesia is said to occur at rates of less than 1:10,000, but these are average figures incorporating both elective and emergency patients with all types of physical conditions. Minor complications occur at predicable rates, even in previously healthy patients. The frequency of symptoms during the first 24 hours following ambulatory surgery is as follows: * Bleeding, vomiting, nausea - Less than 5% * Fever - 5-15% * Dizziness, headache, drowsiness, hoarseness - More than 15% * Sore throat - 25% * Incisional pain - 30% An excellent recent review of the literature concerning anesthesia-related morbidity and mortality will be of interest to readers wanting more information.1 border= border= Preparation for General Anesthesia Safe and efficient anesthesia practice requires certified personnel, appropriate drugs and equipment, and an optimized patient. These requirements need to be adapted to the context; no one would criticize a trauma surgeon attending a patient trapped in the wreckage of a motor vehicle accident for administering a bolus dose of intravenous (IV) ketamine at the roadside to amputate a limb and free the victim. Such a general anesthetic, given in an uncontrolled fashion by an individual with no anesthesia training, would be completely inappropriate for an elective surgical procedure. Minimum requirements Minimum infrastructure requirements for general anesthesia include a well-lit space of adequate size, a source of pressurized oxygen (either piped in or from cylinders), an effective suction device, and equipment to continuously monitor heart rate and rhythm, blood pressure, oxygen saturation, and temperature. Additional monitoring requirements exist in certain jurisdictions. Beyond this, some equipment is needed to deliver the anesthetic agent. This may be as simple as needles and syringes if the drugs are to be administered entirely intravenously, but, in most circumstances, this means the availability of a properly serviced and maintained anesthetic gas delivery machine. An array of routine and emergency drugs, including supplies of Dantrolene sodium (the specific treatment for malignant hyperthermia), airway management equipment, a cardiac defibrillator, and a recovery room staffed by properly trained individuals completes the picture. Preparing the patient The patient should be adequately prepared. The most efficient method is for the patient to be reviewed by the person responsible for giving the anesthetic well in advance of the surgery date. Persons without concomitant medical problems may need little more than a quick medical review and the opportunity to discuss anesthetic questions or concerns. Those with comorbidity in general should be optimized for the procedure. Patients with diabetes, coronary artery disease, chronic bronchitis and emphysema, and other chronic aliments should be stable. The question of whether such a disease state is under optimal control is usually a simple matter of good clinical judgment and can be determined by anyone who asks the appropriate questions. However, a few areas exist in which preoperative review by an anesthesiology provider can predict and prevent major adverse events. Foremost amongst these is a careful examination of the patient's airway anatomy. Identification of 1 or more of these anomalies may indicate that management of the patient's airway might prove difficult under anesthesia. Airway management Possible or definite difficulties with airway management include the following: * Small or receding jaw * Prominent maxillary teeth * Short neck * Limited neck extension * Poor dentition * Tumors of the face, mouth, neck, or throat * Facial trauma * Interdental fixation * Hard cervical collar * Halo traction Various scoring systems have been created using orofacial measurements to predict difficult intubation. The most widely used is the Mallampati score, which identifies patients in whom the pharynx is not well visualized through the open mouth. High Mallampati scores predict difficult intubation with good but not perfect accuracy. * Often, such histories describe factors such as prolonged postoperative vomiting or slow emergence, which, while important, do not cause undue concern for the patient at hand. * Of much greater concern is a history of high temperature under anesthesia or any form of anesthesia complication that resulted in death or the necessity for intensive care. * When suspicion of an adverse event is high but a similar anesthetic technique must be used again, obtaining records from other institutions may be necessary. Other requirements The necessity to come to the operating room with an empty stomach is well known to health professionals and the lay public alike. * While aspiration of food or fluids into the lungs during anesthesia is a serious complication, do not forget that depriving the patient of fluid is not without risk, particularly in the case of small children. The aim is to strike a reasonable balance between safe anesthetic care and dehydration. * Most anesthetists would agree that solid food should be avoided for 6 hours and clear fluids for up to 4 hours prior to the induction of anesthesia, but even anesthesia specialty societies do not agree absolutely on these intervals. With a few exceptions, patients should continue to take regularly scheduled medications up to and including the morning of surgery. Obvious exceptions include the following: * Discontinue anticoagulants, including aspirin, in good time to avoid increased surgical bleeding. * Avoid oral hypoglycemics on the day of surgery and manage blood glucose using intravenous dextrose and insulin. * Metformin is an oral hypoglycemic agent that is associated with the development of profound and occasionally irreversible metabolic acidosis under general anesthesia. Discontinue it 48 hours prior to the surgery date. * Since monoamine oxidase inhibitors are associated with anesthetic drug interactions, discontinue them prior to surgery if possible. Recent catastrophes under anesthesia have focused attention on the interaction between nonprescribed medications and anesthetic drugs, including interactions with vitamins, herbal preparations, traditional remedies, and food supplements. Good information on the exact content of these preparations is often hard to obtain.2 The routine performance of standard batteries of preoperative tests is no longer justified. These waste resources and time and expose the patient to needless venipuncture and radiation. From the anesthesia point of view, the most efficient route is to have the anesthesia provider order his or her own tests, based on the known comorbid conditions, drug history, and surgical plan. The routine chest radiograph is particularly egregious, as it rarely yields information that might alter the anesthetic management in patients without known cardiopulmonary disease. The Process of Anesthesia Premedication: The first stage of a general anesthetic * This stage, which is usually conducted in the surgical ward or in a preoperative holding area, is something of a throwback to the early days of ether and chloroform anesthesia when drugs such as morphine and scopolamine were routinely administered to make the inhalation of these highly pungent vapors more tolerable. * The goal of this stage of the anesthesia process is to have the patient arrive in the operating room in a calm, relaxed frame of mind while causing minimal interference with breathing and cardiovascular status. * For many patients, this step is either unnecessary or impractical because of the way in which operations are scheduled. * The most commonly used premedicants are short-acting benzodiazepines. Midazolam syrup is often given to children to facilitate calm separation from their parents prior to anesthesia. In anticipation of surgical pain, nonsteroidal anti-inflammatory drugs or acetaminophen can be administered preemptively, and when a history of gastroesophageal reflux exists, H2 blockers and antacids are administered. An unresolved debate in the anesthesia community is whether to administer preoperative and intraoperative beta-blockers to those with risk factors for coronary disease to prevent myocardial infarction. A large international trial is currently under way to address this question. * Where appropriate facilities are available, an excellent alternative to oral premedicants is the titration of small doses of intravenous fentanyl and midazolam by a nurse in the preoperative holding area. * Drying agents (eg, atropine, scopolamine) are now only administered routinely in anticipation of a fiberoptic endotracheal intubation. * The patient is transferred to the operating table and baseline vital signs are obtained. Induction: The patient is now ready for induction, which is usually the most critical part of the anesthesia process. * In many ways, induction of general anesthesia is analogous to an airplane taking off. It is the transformation of a waking patient into an anesthetized one. * This can be achieved by intravenous injection of induction agents (drugs that work rapidly, such as thiopental and propofol), by the slower inhalation of anesthetic vapors from a face mask, or a combination of both. * For the most part, contemporary practice dictates that adult patients and most children be induced with intravenous drugs, this being a rapid and minimally unpleasant experience for the patient. However, the arrival of sevoflurane, a new and well-tolerated anesthetic vapor, has led to something of a renaissance of elective inhalation induction of anesthesia in adults. * In addition to the induction drug, most patients receive an injection of narcotic analgesic. A wide range of synthetic and naturally occurring narcotics with different properties is available. Induction agents and narcotics work synergistically to induce anesthesia. In addition, anticipation of events that are about to occur, such as endotracheal intubation and incision of the skin, generally raises the blood pressure and heart rate of the patient. Narcotic analgesia helps preempt this undesirable response. * The next step of the induction process is the securing of the airway. This may be a simple matter of manually holding the patient's jaw such that his or her natural breathing is unimpeded by the tongue or may demand the insertion of a prosthetic airway device such as a laryngeal mask airway or endotracheal tube. A variety of factors are considered when making this decision. The major issueis whether the patient requires an endotracheal tube. * Indications for endotracheal intubation under general anesthesia include the following: o Potential for airway contamination (full stomach, gastroesophageal [GE] reflux, gastrointestinal [GI] or pharyngeal bleeding) o Surgical need for muscle relaxation o Predictable difficulty with endotracheal intubation or where anesthetist's access to the airway during the case will be difficult (lateral or prone position) o Surgery of the mouth or face o Prolonged procedure anticipated * Not all surgery requires muscle relaxation. In this context, only the major muscle groups of the thorax and abdomen are considered. * If surgery is taking place in these areas, then in addition to the induction agent and narcotic, an intermediate or long-acting muscle relaxant drug is administered. This paralyzes muscles indiscriminately, including the muscles of breathing. Therefore, the patient's lungs must be ventilated under pressure, necessitating an endotracheal tube. * Persons who, for anatomic reasons, are likely to be difficult to intubate are usually intubated electively at the beginning of the procedure, using a fiberoptic bronchoscope or other advanced airway tool (Hagberg, 2002). This prevents a situation in which attempts are made to manage the airway with a lesser device, only for the anesthetist to discover that oxygenation and ventilation are inadequate. At that point during a surgical procedure, swift intubation of the patient can be very difficult, if not impossible. Maintenance phase: At this point, the drugs used to initiate the anesthetic are beginning to wear off, and the patient must be kept anesthetized with a maintenance agent. * For the most part, this refers to the delivery of anesthetic gases (more properly termed vapors) into the patient's lungs. These may be inhaled as the patient breathes himself or delivered under pressure by each mechanical breath of a ventilator. * The maintenance phase is usually the most stable part of the anesthesia. However, understanding that anesthesia is a continuum of different depths is important. A level of anesthesia that is satisfactory for surgery to the skin of an extremity, for example, would be inadequate for manipulation of the bowel. * Appropriate levels of anesthesia must be chosen both for the planned procedure and for its various stages. In complex plastic surgery, for example, a considerable period of time may elapse between the completion of the induction of anesthetic and the incision of the skin. During the period of skin preparation, urinary catheter insertion, and marking incision lines with a pen, the patient is not receiving any noxious stimulus. This requires a very light level of anesthesia, which must be converted rapidly to a deeper level just before the incision is made. When the anesthesia provider and surgeon are not accustomed to working together, good communication (eg, warning of the start of new stimuli, such as moving the head of an intubated patient or commencing surgery) facilitates preemptive deepening of the anesthetic. This maximizes patient safety and, ultimately, saves everyone's time. As the procedure progresses, the level of anesthesia is altered to give the minimum amount necessary to ensure adequate anesthetic depth. Traditionally, this has been a matter of clinical judgment, but new processed EEG machines give the anesthetist a simplified output in real time, corresponding to anesthetic depth. These devices have yet to become universally accepted as vital equipment. * If muscle relaxants have not been used, inadequate anesthesia is easy to spot. The patient will move, cough, or pupillary obstruct his airway if the anesthetic is too light for the stimulus being given. * If muscle relaxants have been used, then clearly the patient is unable to demonstrate any of these phenomena. In these patients, the anesthesiologist must rely on careful observation of autonomic phenomena such as hypertension, tachycardia, sweating, and capillary dilation to decide that the patient requires a deeper anesthetic. * This requires experience and judgment. It is from failure to recognize such signs that tragic and highly publicized cases of awareness under anesthesia are caused. * Excessive anesthetic depth, on the other hand, is associated with decreased heart rate and blood pressure, and, if carried to extremes, can jeopardize perfusion of vital organs or be fatal. Short of these serious misadventures, excessive depth results in slower awakening and more side effects. As the surgical procedure draws to a close, the patient's emergence from anesthesia is planned. Experience and close communication with the surgeon enable the anesthesiologist to predict the time at which the application of dressings and casts will be complete. * In advance of that time, anesthetic vapors have been decreased or even switched off entirely to allow time for them to be excreted by the lungs. * Excess muscle relaxation is reversed using specific drugs and adequate long-acting narcotic analgesic to keep the patient comfortable in the recovery room. * If a ventilator has been used, the patient is restored to breathing by himself and, as anesthetic drugs dissipate, the patient emerges to consciousness. * Emergence is not synonymous with removal of the endotracheal tube or other artificial airway device. This is only performed when the patient has regained sufficient control of his or her airway reflexes. Anesthesia Drugs in Common Use A number of choices exist for every aspect of anesthetic care; the way in which they are sequenced probably depends more on the personal preference of the person administering them. Induction agents * For 50 years, the most commonly used induction agents were rapidly acting, water-soluble barbiturates such as thiopental, methohexital, and thiamylal. * These drugs are still commonly in use today, have an enormous record of safety and reliability, and are economical. * More recently, propofol, a nonbarbiturate intravenous anesthetic, has displaced barbiturates in many anesthesia practices. o The use of propofol is associated with less postoperative nausea and vomiting and a more rapid, clear-headed recovery. o In addition to being an excellent induction agent, propofol can be administered by slow intravenous infusion instead of vapor to maintain the anesthesia. o Among its disadvantages are the facts that it often causes pain on injection and it is prepared in a lipid emulsion, which if not handled using meticulous aseptic precautions, can be a medium for rapid bacterial growth. Anesthesia can also be induced by inhalation of a vapor. This is how all anesthetics were once given and is a common and useful technique in uncooperative children. It is reemerging as a choice in adults. Halothane and sevoflurane are the most commonly used drugs for this purpose. Traditional narcotic analgesics * Morphine, meperidine, and hydromorphone are widely used in anesthesia as well as in emergency rooms, surgical wards, and obstetric suites. * In addition, anesthesia providers have at their disposal a range of synthetic narcotics, which, in general, cause less fluctuation in blood pressure and are shorter acting. These include fentanyl, sufentanil, alfentanil, and remifentanil. Remifentanil is the newest drug in this class and has such a short duration of action that it must be administered as a continuous infusion. Muscle relaxants come in many varieties * Succinylcholine, a rapid-onset, short-acting depolarizing muscle relaxant, is the drug of choice when rapid muscle relaxation is needed. o For decades, anesthetists have used it extensively despite a number of predictable and unpredictable adverse effects associated with its use. o The search for a drug that replicates its onset and offsets speed without its adverse effects is the holy grail of muscle relaxant research. * Other relaxants have durations of action ranging from 15 minutes to more than 2 hours. * Older drugs in this class were often associated with changes in heart rate or blood pressure, but the newer ones are devoid of these adverse properties. * Muscle relaxants generally are excreted by the kidney, but some preparations are broken down by plasma enzymes and can be used safely in partial or complete renal failure. * Pancuronium is an established drug that is still in widespread use because of its low cost and familiarity, especially in intensive care units; rocuronium, mivacurium, and cisatracurium are more likely to be used by contemporary anesthesiologists. Anesthetic vapors * These are highly potent chlorofluorocarbons, which are delivered from precision vaporizers directly into the patient's inhaled gas stream. They may be mixed with nitrous oxide, a much weaker but nonetheless useful anesthetic gas. * The prototype of modern anesthetic vapors is halothane. It has an unparalleled track record of safety and efficacy, though it is associated with rare but devastating hepatic necrosis to a greater extent than other agents. * In the 1980s, it was displaced by isoflurane and enflurane, agents that were cleared from the lungs faster and thus were associated with more rapid anesthetic emergences. * In the late 1990s, 2 new vapors became very popular, desflurane and sevoflurane. These drugs are much more maneuverable than their predecessors and are associated with much more rapid emergence. Intense commercial interest is present in anesthesia drug research, and the continuous introduction of new and better drug products for many years to come seems inevitable. Historical Perspective * Original discoverer of general anesthetics o Crawford Long: 1842, ether anesthesia * Chloroform introduced o James Simpson: 1847 * Nitrous oxide o Horace Wells 19th Century physician administering chloroform Historical Perspective o October 16, 1846 o Gaseous ether * Ether no longer used in modern practice, yet considered to be the first ideal anesthetic * Cyclopropane: 1929 o Most widely used general anesthetic for the next 30 years * Halothane: 1956 o Team effort between the British Research Council and chemists at Imperial Chemical Industries o Preferred anesthetic of choice * Thiopental: Intravenous anesthetic Definition of General Anesthesia Reversible, drug-induced loss of consciousness General Anesthesia * Intravenous Thiopental: Intravenous anesthetic * Inhalational Propofol Etomidate Ketamine Halothane Isoflurane Sevoflurane Which neuronal structures are most important for the anesthetic end points of interest? General Anesthesia General anesthetics produce an unconscious state. In this state a person is: * unaware of what is happening * pain-free * immobile * free from any memory of the period of time during which he or she is anesthetized What are the complications of anesthesia? Minor complications include postoperative sore throat and nausea and vomiting. These are not normally very troublesome and resolve quickly. Serious complications from anesthesia are very rare. What about postoperative pain relief? The purpose of this review is to suggest methods of relieving acute postoperative pain. It will discuss how the use of peripherally-acting drugs (such as the non-steroidal anti-inflammatory drugs, centrally-acting agents (such as opioids) and local anaesthetics can achieve this. Guidelines are offered for pain relief in children and the elderly. Further suggestions are made about the route of administration of analgesic drugs and factors which may alter the complaint of pain following surgery. This review is not comprehensive but is intended to summarise current thought about the practical management of postoperative pain in an understandable and accessible fashion. The effective relief of pain is of paramount importance to anyone treating patients undergoing surgery. This should be achieved for humanitarian reasons, but there is now evidence that pain relief has significant physiological benefit. Not only does effective pain relief mean a smoother postoperative course with earlier discharge from hospital, but it may also reduce the onset of chronic pain syndromes. Pain serves a biological function. It signals the presence of damage or disease within the body. In the case of postoperative pain it is the result of the surgery, but the principles outlined in this article apply also to the management of other acute pains such as those following burns or injury. The goal for postoperative pain management is to reduce or eliminate pain and discomfort with a minimum of side effects as cheaply as possible. Postoperative pain relief must reflect the needs of each patient and this can be achieved only if many factors are taken into account. These may be summarised as clinical factors, patient-related factors and local factors. In the final analysis the ultimate determinant of the adequacy of pain relief will be the patient's own perception of pain. Clinical factors The site of the surgery has a profound effect upon the degree of postoperative pain a patient may suffer. Operations on the thorax and upper abdomen are more painful than operations on the lower abdomen which, in turn, are more painful than peripheral operations on the limbs. However, any operation involving a body cavity, large joint surfaces or deep tissues should be regarded as painful. In particular, operations on the thorax or upper abdomen may produce widespread changes in pulmonary function, an increase in abdominal muscle tone and an associated decrease in diaphragmatic function. The result will be an inability to cough and clear secretions which may lead to lung atelectasis (collapse of lung tissue) and pneumonia. Matters are made worse by postoperative bowel distension or tight dressings. Pain causes an increase in the sympathetic response of the body with subsequent rises in heart rate, cardiac work and oxygen consumption. Prolonged pain can reduce physical activity and lead to venous stasis and an increased risk of deep vein thrombosis and consequent pulmonary embolism. In addition, there can be widespread effects on gut and urinary tract motility which may lead, in turn, to postoperative ileus, nausea, vomiting and urinary retention. These problems are unpleasant for the patient and may prolong hospital stay. The choice of pain-relieving techniques may be influenced by the site of surgery. Equally, it may be influenced by drug availability and familiarity with different methods of analgesia. For example, although patient-controlled analgesia (PCA), has often been shown to be better than the intermittent delivery of intramuscular opioids it does not produce as much pain relief as epidural opioid analgesia. Equally, a local anaesthetic block can effectively relieve pain, but only for the duration of the particular agent used. Choice of technique will also be influenced by the degree of training and expertise of the staff. For many years, the standard method of treating postoperative pain in the developed world has been intramuscular opioid (usually morphine). The effects of opioid drugs vary greatly among patients and thus individual responses cannot be predicted. Many studies have shown that under-treatment of acute postoperative pain occurs because doctors and nurses overestimate the length of action and the strength of the drugs and that they have fears about respiratory depression, vomiting, sedation and dependency. Improvement can be achieved by better education for all staff concerned with the delivery of postoperative pain relief and by making the assessment and recording of pain levels part of the routine management of each patient. Ideally, a named individual should be responsible in each hospital for the delivery and teaching of acute pain management. Patient-related factors Although it may be possible to predict, to a degree, the amount of postoperative pain knowing the site and nature of the surgery, other factors may alter the amount of pain suffered by the individual patient. The nature and intended purpose of the surgery may be important. If the proposed operation will lead to a restoration of normal function, for example, a hernia repair or fixation of a fracture, it is likely to be seen in a positive way by the patient. Where the outcome is not clear, for example, an operation for cancer or to investigate an unknown pain, the patients' fear and anxiety may lead to high levels of postoperative pain being reported. Patients who are afraid of anaesthesia or surgery may report more pain and this can be very difficult to treat. Adequate time must be allowed to explain the intended operation and the steps that will be taken to ensure pain relief afterwards. It is important to establish the expectations of the patient before surgery. Some may fear the unknown and others may have previous experience of surgery or have heard stories from friends and relatives that present the postoperative period in an unfavourable way. An adequate and friendly explanation in simple terms will often reduce anxiety and minimise misunderstandings about the nature and purpose of the proposed surgery. Local Factors A major problem in some parts of the world is that certain drugs, such as morphine, which are the mainstay of postoperative pain relief in many places, are not available. In addition, economic factors may mean that techniques of pain relief such as patient-controlled analgesia (P.C.A.) are unavailable and that techniques of regional anaesthesia which employ continuous infusions through disposable catheters are impossible. It is no use advocating techniques such as these if they are beyond local resources. It is better to maximise the effective use of local anaesthetic techniques and intermittent delivery of such analgesic drugs as are available. This review will discuss the use of the more advanced techniques in broad terms with the hope that the availability of both drugs and equipment can be improved in the longer term. In general, the introduction of new and potentially expensive techniques is resisted by administration and professions alike. However, the introduction of such techniques may yield increased benefits in the form of improved recovery and faster discharge from hospital with consequent reductions in the cost of health care. Effective postoperative pain management may be encouraged by education of politicians, administrators, professional colleagues and patients. Assessment of pain severity Assessment of pain is in two parts; before the operation to make a pain management plan and afterwards to see whether the plan is working. The preoperative assessment includes the factors mentioned previously, as well as variables such as age, sex, weight, degree of obesity, current drug intake or past history of drug-related problems. Potential difficulties caused by language or culture are also assessed. There may be problems related to age, and relief of pain in children and the elderly are considered under separate headings. There is some evidence to suggest that the use of opioid premedication establishes a level of analgesic control from the outset. There is however no evidence to support the use of local anaesthetic blocks or peripherally acting drugs in this pre-emptive fashion. Rating scales are the most commonly used method of assessing acute pain and its relief. In practice, these are either words or numbers. In addition, a numerical value can be derived from a visual analogue scale. All these methods are simple, can be readily understood and require little in the way of technology or resources. Words can be translated into any language and a simple five point scale is normally used. An example is shown below. Pain Scale: No pain mild moderate severe excruciating Numbers can be assigned to each of the words for recording purposes (0-4). A simple numerical rating scale would require the patient to choose a number between 0 and 10 to represent their pain. Zero indicates that the patient has no pain and 10 means that the pain is as bad as can be imagined. Visual analogue scales have a 10cm line which is marked as shown below. The patient is asked to make a vertical mark on the line to indicate the intensity of their pain. Pain Scale: No pain --line-- excruciating There should be no other markings, numbers or words along the line as this tends to influence the results. It is most important to ensure that the patient understands the two end points. A small percentage of patients including the elderly and those with limited education have difficulty with visual analogue scales. Most can be trained by giving examples of familiar pain problems and relating these to positions along the line. If pain is being assessed regularly, then at the time of assessment the patient should not be able to see any other score as this may affect his decision. A visual analogue can be scored by measuring from the left side how far the patient marked towards the maximum pain end. This number can then be used to compare changes in the pain level. Assessment of pain in infants or patients who cannot communicate can be difficult. Pain can be assessed with picture scales using varied facial expressions or by clinical observation (for example: sighing, groaning, sweating, ability to move). The latter method has the advantage that it does not rely on the patient to any great degree and can be carried out when other vital signs such as heart rate and blood pressure are being assessed. Asking the patient to take a deep breath or to cough or move will also provide useful information and it is important to emphasise that measurement of pain while the patient is at rest is unlikely to indicate the need for analgesia. Pain relief should be assessed when the patient is active. Simple questions like "where does it hurt? " and "what does it feel like?" may allow a qualitative evaluation of pain after surgery. Pain distant from the operative site may indicate complications not associated with the procedure which may require separate treatment. Complaints of generalised pain all over the body may represent stress, anxiety, or in some cases fever. The description of the pain may indicate the cause. For example sharp, stabbing pain is associated with surgery, whereas numbness or tingling may mean nerve compression or ischaemia. Unusual or vague descriptions are more likely to be due to non-organic causes. It may be difficult to assess pain in the early post-operative period by any of the methods described. It should be stressed that the assessment must be made at regular intervals and should form part of the routine postoperative observations. The progress of the patient is more easily assessed if results are charted in graphical form rather than as a number. Nursing, auxiliary and trainee medical staff should be encouraged to use assessment of pain routinely. Furthermore, they should be given training in the use of all forms of analgesic technique so they become confident in their use. Experience suggests that frequent assessment and delivery of analgesia whenever needed become a routine once the benefit to the patient is recognised. Pharmacology The World Health Organisation Analgesic Ladder was introduced to improve pain control in patients with cancer pain. However, it has lessons for the management of acute pain as it employs a logical strategy to pain management. As originally described, the ladder has three rungs. [Fig 1a] In the first instance peripherally acting drugs such as aspirin, paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs) are given. If pain control is not achieved, the second part of the ladder is to introduce weak opioid drugs such as codeine or dextropropoxyphene together with appropriate agents to control and minimise side effects. If effective control is not achieved by this change, the final rung of the ladder is to introduce strong opioid drugs such as morphine. Analgesia from peripherally acting drugs may be additive to that from centrally-acting opioids and thus, the two are given together. The World Federation of Societies of Anaesthesiologists (WFSA) Analgesic Ladder has been developed to treat acute pain. Initially, the pain can be expected to be severe and may need controlling with strong analgesics in combination with local anaesthetic blocks and peripherally acting drugs. The oral route for the administration of drugs may be denied because of the nature of the surgery and drugs may have to be given by injection. Normally, postoperative pain should decrease with time and the need for drugs to be given by injection should cease. The second rung on the postoperative pain ladder is the restoration of the use of the oral route to deliver analgesia. Strong opioids may no longer be required and adequate analgesia can be obtained by using combinations of peripherally acting agents and weak opioids. The final step is when the pain can be controlled by peripherally acting agents alone. Local Anaesthetics Regional anaesthetic techniques used for surgery may have positive respiratory and cardiovascular effects associated with reduced blood loss and excellent pain relief which can improve convalescence. Clearly, any technique that can be used for the surgical procedure will provide near perfect postoperative pain relief if it can be prolonged beyond the time of the surgery. There are many straightforward local anaesthetic techniques which can be continued into the postoperative period to provide effective pain relief. Most of these can be carried out with minimal risk to the patient and include local infiltration of incisions with long-acting local anaesthetics, blockade of peripheral nerves or plexuses and continuous block techniques peripherally or centrally. It is a mistake to expect 100% analgesia in every patient using a local anaesthetic technique alone as postoperative pain has many sources. The true place of local anaesthetic techniques is as part of a prepared plan for overall management that employs these techniques in conjunction with appropriate analgesic drugs. As pain is multifactorial in origin it is logical that management should consist of a combination of approaches in order to achieve the best results. Infiltration of a wound with a long-acting local anaesthetic such as bupivacaine can provide effective analgesia for several hours. Further pain relief can be obtained with repeat injections or by infusions via a thin catheter. Blockade of plexuses or peripheral nerves will provide selective analgesia in those parts of the body supplied by the plexus or nerves. These techniques can either be used to provide anaesthesia for the surgery or specifically for postoperative pain relief. Depending upon the availability of drugs and equipment either single shot or continuous infusion techniques can be used to block brachial plexus, lumbar plexus, intercostal, sciatic, femoral or any nerves supplying the specific area of the surgery. These techniques may be especially useful where a sympathetic block is needed to improve postoperative blood supply or where central blockade such as spinal or epidural blockade is contraindicated. Spinal anaesthesia provides excellent analgesia for surgery in the lower half of the body and pain relief can last many hours after completion of the operation if long-acting drugs containing vasoconstrictors are used. Continuous analgesia using the spinal route has been tried but epidural analgesia is used more widely. The use of the epidural technique requires experienced practitioners and specific training for nursing staff in the postoperative management of patients. In addition, great care must be taken to maintain sterility if a continuous technique is to be used. Epidural catheters can be placed in either the cervical, thoracic or lumbar regions but lumbar epidural blockade is the most commonly used. Although continuous infusions of local anaesthetic may produce very effective analgesia, they may also produce undesirable side effects such as hypotension, sensory and motor block, nausea and urinary retention. Combination of local anaesthetic drugs with opioids given centrally may reduce some of these problems (see intrathecal and epidural opioids) All doses assume healthy adult patients and maximum permissible dosage should be calculated on the basis of body weight, particularly in the case of children (see section on paediatric pain). Intravascular injection of local anaesthetic drugs can produce serious or life-threatening effects at much smaller doses than the maxima quoted. Local anaesthetic injections at any site can form part of balanced analgesia where a mixture of techniques provides pain relief. This has the advantage of decreasing the dosage of each drug needed and diminishing the likelihood of side effects. The small delay that results from performance of the blocks is outweighed by the benefit to the patient. Toxicity The most important factor in the prevention of local anaesthetic toxicity is the avoidance of intravascular injection. Careful aspiration is vital especially if the needle is moved. However, a negative aspiration test is not an absolute guarantee of correct needle placement. Inject slowly and watch carefully for signs of toxicity such as buzzing in the ears, a feeling of numbness in the face and lips and a feeling of muscle twitching. If toxicity is suspected the injection should be stopped and the patient's respiration and circulation assessed. Provided hypoxia is avoided little other treatment is needed. Cardiovascular depression should be treated by raising the legs, giving intravenous fluids and administering a vasopressor such as ephedrine. Major collapse requires full resuscitation. Convulsions may occur and need management of airway, breathing and circulation as well as control of the fitting with diazepam or thiopentone. Non-opioid analgesics The most commonly used analgesic agents throughout the world are drugs in this group such as aspirin, paracetamol and the non-steroidal anti-inflammatory drugs (NSAIDs). These are the main analgesic treatment for mild to moderate pain. Aspirin is an effective analgesic and is widely available throughout the world. It is active orally within a short period as it is rapidly metabolised into salicylic acid which has analgesic and, probably, anti-inflammatory activity. Salicylic acid has a half life of about four hours at therapeutic doses. Excretion is dose dependent and high doses will be excreted more slowly. The length of action may be reduced if aspirin is given with antacids. Aspirin has major gastrointestinal side effects and may cause nausea, sickness or gastrointestinal bleeding because of antiplatelet effects which are irreversible. For this latter reason the use of aspirin after surgery should be withheld if alternatives are available. Diflunisal and Choline salicylate are related compounds without this latter problem. Aspirin has an epidemiological association with Reye's syndrome and should not normally be used to provide analgesia in children under the age of 12 years. Doses range from a minimum of 300mg orally, 4 hourly, to a maximum of 8g, orally daily. Paracetamol has analgesic and antipyretic properties but little anti-inflammatory effect. It is well absorbed orally and is metabolised almost entirely in the liver. It has few side effects in normal dosage and is widely used for the treatment of minor pain. It causes hepatotoxicity in overdosage by overloading the normal metabolic pathways with the formation of a toxic metabolite. Doses range from a minimum of 500 mg, orally, 4 hourly to a maximum of 4g, orally daily. NSAIDs have both analgesic and anti-inflammatory actions. Their mechanism of action is predominantly by inhibition of prostaglandin synthesis by the enzyme cyclo-oxygenase which catalyses the conversion of arachidonic acid to the various prostaglandins that are the chief mediators of inflammation. All NSAIDs work in the same way and thus there is no point in giving more than one at a time. In addition, there is a widespread individual variation in response to these agents and thus there is no drug of choice. NSAIDs are, in general, more useful for superficial pain arising from the skin, buccal mucosa, joint surfaces and bone. They may be usefully combined with opioids due to their different modes of action. The choice of a NSAID should be made on the basis of availability, cost and length of action. If pain is likely to be persistent over a long period of time it may be logical to choose an agent with a long half life and prolonged clinical effect. However, this group of drugs has a high incidence of side effects with prolonged use and caution should be exercised. All NSAIDs have antiplatelet activity leading to increased bleeding time. These drugs also inhibit prostaglandin synthesis in the gastric mucosa and may thus produce gastric bleeding as a side effect. Care should be exercised when using these drugs in patients with asthma or impaired renal function. The following should be regarded as relative contraindications to the use of NSAIDs: Any history of peptic ulceration, gastrointestinal bleeding or bleeding diathesis; operations associated with high blood loss, asthma, moderate to severe renal impairment, dehydration and any history of hypersensitivity to NSAIDs or aspirin. NSAIDs are available in a variety of formulations: tablet, injection, topical cream and suppository. The incidence of side effects and adverse reactions with an individual drug is similar regardless of the route of delivery. Ibuprofen is the drug of choice if the oral route is available. It is clinically effective, cheap and has a lower side effects profile than other NSAIDs. Alternatives are diclofenac, naproxen, piroxicam, ketorolac, indomethacin and mefenamic acid. Where the oral route is not available the drug may be given by another route such as suppository, injection or topically. Aspirin and most of the NSAIDs are available as suppositories and are well absorbed. Weak opioids Codeine is a weak opioid analgesic which is derived from opium alkaloids (as is morphine). Codeine is markedly less active than morphine, has predictable effects when given orally and is effective against mild to moderate pain. It may be combined with paracetamol but care should be taken not to exceed the maximum recommended dose of paracetamol when using combination tablets. Doses range from 15 mg to 60 mg 4 hourly with a maximum of 300 mg daily. (If pain is not responding to maximum doses a stronger drug should be used if available) Dextropropoxyphene is structurally related to methadone but is a relatively poor analgesic. It is often marketed in combination with paracetamol. and the same precautions should be observed. It offers few, if any, advantages over codeine. Doses range from 32.5 mg (in combination with paracetamol) to 60 mg 4 hourly with a maximum of 300 mg daily. (If pain is not responding to maximum doses a stronger drug should be used) Combinations of weak opioids and peripherally acting drugs are useful in minor surgical procedures where excessive pain is not anticipated or for outpatient use: Paracetamol 500 mg/codeine 8mg tablets. 2 tablets 4 hourly to a maximum of 8 tablets daily. If analgesia is insufficient - Paracetamol 1g orally with Codeine 30 to 60 mg 4 to 6 hourly to a maximum of 4 doses. Strong Opioids Severe pain arising from deep or visceral structures requires the use of strong opioids (see *INFO* table 3). Appropriate treatment begins with an understanding of the correct drug, route of administration and the mode of action. Early administration will achieve effective analgesic concentrations and make it easier to maintain the therapeutic level of the drug in the blood. Once a satisfactory level of pain relief has been achieved this can be sustained by regular administration of opioid regardless of whether the intramuscular, subcutaneous, intravenous, oral, sublingual or rectal route is chosen. Administration of adequate doses of analgesic may be inhibited because of side effects, notably nausea and vomiting. The oral route of administration may not be available immediately after surgery. If gastrointestinal function is normal following surgery that has been superficial or minor in nature strong analgesia is not required. However, the oral route may be available as the patient recovers from major surgery and strong analgesics such as morphine are effective when taken by mouth. When the patient is unable to take drugs by mouth other routes of administration should be used. In general, effective analgesia can be provided by intramuscular injection despite the recognised drawbacks of this method. Conventional intramuscular delivery of opioid analgesics has the advantage of representing familiar practice and has inherent safety for this reason. The technique is inexpensive and the gradual onset of pain relief permits easy assessment of possible overdose. A disadvantage of the method may be that the dose is too large (side effects) or too small (no pain relief). In addition, the injections are painful and the onset of pain relief is delayed while the drug is absorbed. Other factors affecting drug absorption. There may be enormous variations in the blood levels and rates of absorption of opioids after intramuscular injection. These may be influenced by the presence of hepatic or renal disease, the extremes of age and the presence of other drug therapy. Any condition that reduces peripheral blood flow can impair drug uptake and thus, reduced body temperature, hypovolaemia and hypotension will all result in lowered uptake from injection sites. Hypothermia and hypothyroidism may both lead to a reduction in metabolism causing an increased sensitivity to drugs. Minimum effective analgesic concentration (MEAC) is the minimum plasma concentration at which analgesia occurs when a drug is given by constant infusion. The variation of MEAC level between different patients accounts for the vast difference in analgesic requirements that may be encountered. This can be illustrated by the large variations in drug demand seen when Patient Controlled Analgesia (PCA) systems are used. This varies between 13 and 44mg/h for pethidine (meperidine), 30 and 100mcg/h for fentanyl and 0.3 and 9mg/h for morphine in different patients. Methods of using opioid drugs The oral route of administration is the most widely used route and most acceptable for the patient. Disadvantages of the oral route to treat acute pain are that absorption of opioids may be reduced by the delay in gastric emptying that follows surgery. This has the dual disadvantage of non-absorption initially, followed by the possibility of a large dose being absorbed when gastrointestinal function resumes. Nausea and vomiting may prevent absorption of drugs administered orally and in addition, there is a reduced bioavailability after metabolism in the gut wall and the liver as the drug is absorbed (first pass metabolism). Thus the oral route may be unsuitable in many instances. The sublingual route offers some theoretical advantages for drug administration. Absorption occurs directly into the systemic circulation as there is no first pass metabolism. Tablets can be removed in the event of overdosage and, because of metabolism, they are unlikely to cause toxicity if they are swallowed. The drug that has been most commonly used by this route is buprenorphine which is rapidly absorped and has a long duration of action (6 h). It is associated with a high incidence of nausea, vomiting and sedation. Rectal administration. Most opioid analgesics are subject to extensive metabolism if given by mouth. The rectal route is a useful alternative, particularly if severe pain is accompanied by nausea and vomiting. Opioids can be delivered successfully by suppository but it is not ideal for the immediate relief of acute pain because of the slow and sometimes erratic absorption, although it is ideally suited for the maintenance of analgesia. Rectal doses for most strong opioids are about half those needed by the oral route. Availability of preparations of opioids for rectal use is very variable throughout the world. Intramuscular administration represents the optimum technique for the developing world where strong opioids are available. As stated previously, this method of analgesia may be associated with peaks and troughs in effect. A simple way of overcoming this problem is to administer the analgesic on a regular 4-hourly basis. In fact, it has been demonstrated that pain relief from intermittent intramuscular injection of opioids can be as good as that from PCA. To achieve this level of analgesia requires regular assessment and recording of pain scores and the development of treatment algorithms for automatic delivery of analgesia depending upon the level of pain recorded. Intravenous administration. For many years it has been common practice to deliver small boluses of opioid both in theatre and the postoperative recovery area to produce immediate analgesia. This has the disadvantage of producing fluctuations in plasma concentrations of the injected drug, although when performed carefully intravenous injection brings more rapid pain relief than other methods. In general however intravenous techniques, by either intermittent injection or by infusion, are unsuitable except in high dependency and intensive therapy units as they are inherently dangerous if the patient is left unsupervised for even a short period. Patient Controlled Analgesia (PCA) became popular when it was realised that individual requirements for opioids varied considerably. Therefore a system was devised whereby patients could administer their own intravenous analgesia and so titrate the dose to their own end-point of pain relief using a small microprocessor - controlled pump. A variety of commercial devices are now available for this purpose. When pain is experienced, the patient self-administers a small bolus dose of opioid and experiences the benefit of this action. Thus they can adjust the level of analgesia required, according to the severity of the pain. In theory, the plasma level of the analgesic will be relatively constant and side effects caused by fluctuations in plasma level will be eliminated. To achieve successful and safe analgesia with PCA requires that the patient understands what is required and this should be explained in detail before the operation. Almost every opioid drug has been used for PCA. In theory, the ideal drug should have rapid onset, moderate duration of action (to prevent the need for frequent demands) and have a high margin of safety between effectiveness and troublesome side effects. Choice usually depends upon availability, personal preference and experience. Once a selection has been made other parameters need to be set including the size of the bolus dose, the minimum time period between doses (the lock-out period) and the maximum dose allowed. Some devices permit the use of a continuous background infusion but for the reasons stated in the section on intravenous administration it will not be considered here. Morphine is the most popular drug and will be used as an example. The ideal dose of morphine has been found to be 1mg. However, regular review is needed in every case to ensure that pain relief is adequate. The aim of the lock-out period is to prevent overdosage occurring because of over -enthusiastic demands for more analgesia. The lock-out time should be long enough for the previous dose to have an effect. In practice, lockout times of between 5 and 10 minutes are enough for most opioids. A maximum dose can be programmed into most PCA devices to prevent overdose. In practice, it is more logical to accept that the analgesic requirements of patients will vary considerably and some patients may require very large amounts to achieve adequate pain relief. PCA need not be administered intravenously and intramuscular, subcutaneous and epidural routes have all been employed. Patients using PCA usually titrate their analgesia to a point where they are comfortable rather than pain free. The reasons for this are not clear but are probably related to fears of overdosage, the need for contact with members of the hospital staff and the expectation of some pain after surgery. The normal pattern of use is for frequent demands to be made in the initial postoperative period and for these to decrease with time. The total amount of opioid used is less with PCA than with intramuscular delivery. The overall incidence of side effects is about the same with the two techniques but the incidence of respiratory depression is less with P.C.A. Where this has occurred it has usually been due to incorrect programming, device malfunction or inappropriate use by third parties. Because of this, devices should be tamperproof and activated only by the patient. The pump should normally be attached to a dedicated intravenous cannula. If it is attached to an existing intravenous infusion it must be through a one way valve to prevent increments of opioid collecting in the giving set which may be delivered later as a large bolus if the infusion rate is increased. Intrathecal and epidural opioids have been used following a wide variety of surgical procedures and other acutely painful conditions. Intrathecal opioids are easy to administer either to provide surgical anaesthesia or as an additional technique when general anaesthesia is given. Many patients will remain comfortable for 24 hours or more after a single injection of intrathecal morphine. The epidural route has been used even more extensively although the reason for this is not clear. It may be that anaesthetists are more familiar with the epidural route for the delivery of long term analgesia and because of the potential advantages in terms of long term catheter use and freedom from post -spinal puncture headache. Side effects are common using these routes of delivery. They include nausea, vomiting, itching (which is much more common with morphine than other drugs) and urinary retention. Of most concern however, as with any opioid, is the possibility of respiratory depression. Early respiratory depression may be caused by systemic drug absorption. Late respiratory depression is from rostral (towards the head) spread in the cerebrospinal fluid and the incidence is increased by factors such as dose, age, posture, aqueous solubility of the drug administered, positive pressure ventilation and increased intra-abdominal pressure It should be assumed that all patients are at risk of this occasional complication and a high level of care and vigilance should be maintained. Many centres recommend that patients receiving analgesia by these methods should be in a high dependency or intensive therapy unit. Trained personnel should be present at all times to check on the rate and depth of respiration and level of consciousness of the patient at regular intervals, protocols should be available for immediate treatment of complications and medical staff have received appropriate training. Respiratory rate alone is insufficient to measure the status of respiration. A more global assessment is necessary particularly during the first 24 hours of treatment. Any patient receiving intrathecal or epidural opioids whose level of consciousness drops must be assumed to have respiratory depression until proved otherwise. Where available, the use of supple-mentary oxygen has been recommended. It is particularly dangerous to prescribe other opioids to patients receiving intrathecal or epidural opioids as this increases the likelihood of clinically significant respiratory depression. Opioid/local anaesthetic mixtures have been adopted in some centres in an attempt to reduce the frequency and severity of side effects seen with infusions of pure local anaesthetics. Dilute concentrations of these agents have been combined with opioids and delivered by infusion through an epidural catheter. These mixtures appear to produce a synergistic effect. Bupivacaine appears to be most suitable for this purpose as dilute solutions produce a very limited motor block. A mixture of bupivacaine 0.1% and morphine 0.01% infused at 3/4ml/h gives good pain relief and permits the patient to walk without the risk of hypotension. Other routes of delivery Transdermal, inhaled and intranasal opioids are among the routes of drug delivery currently under development. Opioid analgesic agents (narcotics) Opioid analgesic drugs act at receptors within the central nervous system. Initially three distinct receptor groups were described (mu, kappa and sigma) on the basis of their binding characteristics. The opioid drugs have differing affinities for these receptors and are described by their receptor affinities. Thus morphine and related compounds are known as mu agonists. Other analgesic agents have differing receptor affinities giving them different clinical properties. Morphine remains the gold standard by which other analgesics are judged. Morphine has a short half life and poor bioavailability. It is metabolised in the liver and clearance is reduced in patients with liver disease, in the elderly and the debilitated. Major side effects include nausea, vomiting, constipation and respiratory depression. Tolerance may occur with repeated dosage but this is highly unlikely to become apparent during the first week of continuous treatment. Parenteral doses range from 2.5mg to a maximum of 20mg. Morphine may need to be prescribed as frequently as 2 hourly. Pethidine is a synthetic opioid which is structurally different from morphine but which has similar actions. It has a short half life and similar bioavailability and clearance to morphine. Pethidine has a short duration of action and may need to be given hourly. Pethidine has a toxic metabolite (norpethidine) which is cleared by the kidney, but which accumulates in renal failure or following frequent and prolonged doses and may lead to muscle twitching and convulsions. Extreme caution is advised if pethidine is used over a prolonged period or in patients with renal failure. Parenteral doses range from 25 mg to a maximum of 150 mg. Frequency of administration 1 to 4 hourly. Methadone is different from morphine and pethidine but has the same actions. It differs from the other agents in that it is well absorbed by mouth and undergoes little metabolism. It is slowly metabolised in the liver and has a very long half life. The resultant prolonged duration of action makes it more suitable for use in chronic pain rather than acute postoperative pain although it has been used successfully for this purpose. Oral doses range from 2.5 mg to 25 mg given 6 to 12 hourly. Fentanyl is used chiefly for intraoperative analgesia because of its relatively short duration of action. It has similar actions and side effects to morphine and is metabolised in the liver. Postoperatively it has been used intrathecally or epidurally as described earlier. Buprenorphine is described as a partial agonist, which, in practical terms, means that it has different properties from drugs which work mainly at the mu receptor. Buprenorphine appears to have some action at all the major opioid receptors. Its most useful attribute is that it can be delivered by the sublingual route. It is rapdly absorbed and has a prolonged duratiuon of action (6 h) but is associated with a high incidence of nausea, vomiting and sedation. Of the opioids, buprenorphine poses the least risk to patients with renal failure as the metabolites are virtually inactive and if accumulation does occur it is of no significance. Sublingual doses range from 200-400 mcg 8 hourly. Nalbuphine and Butorphanol are known as agonist/antagonists as unlike conventional opioids, they act at the kappa receptor rather than the mu receptor. Both have been used to provide postoperative analgesia by intermittent, continuous and PCA techniques. They exhibit a ceiling effect for analgesic activity (which has limited their popularity) and also for respiratory depression which should make clinical use safer. They are alleged to have a lower abuse potential than conventional opioid agents. Side effects and toxicity Opioid analgesics share many side effects though the degree may vary between agents. The most common include nausea, vomiting, constipation and drowsiness. Larger doses produce respiratory depression and hypotension. The specific antidote naloxone is indicated if there is coma or very slow respiration. Because of its short action, repeated injections of 200 - 400 mcg intravenously may be necessary. Alternatively, it may be given by continuous intravenous infusion, the rate of administration being adjusted according to response. Pain relief in children Management of pain in children is often inadequate and there is no evidence to support the idea that pain is less intense in neonates and young children due to their developing nervous system. Children tend to receive less analgesia than adults and the drugs are often discontinued sooner. Furthermore, it is simply not true that potent analgesics are dangerous when used in children because of the risks of side effects and addiction. As with all pain, successful management depends upon the identification and treatment of all the factors which contribute, in particular fear and anxiety. In this context, careful explanations to child and parents can be helpful. A major problem in treating pain in children is associated with the difficulty in assessment Assessment presents a major challenge, especially in those patients who cannot explain how they feel and who cannot understand the relationship between the treatment and the pain. The worst response is to ignore the presence of pain and the best is to assess the pain and the patients response to treatment as thoroughly as possible. In very young children observational measures may be helpful, but absence of these signs does not rule out the existence of pain. Assessing simple factors such as whether or not the child is asleep, crying, relaxed, tense or are responding to their parents may be used to create a cumulative pain score. Children over four are better able to report pain and are able to use colour scales, pictures of varying facial expression and often visual analogue scales. Management of pain in children needs to be handled more actively than in adults. Greater effort should be made to anticipate pain as children cannot be relied upon to ask for analgesia as might an adult. It may be better to establish a schedule of regular analgesia. The route of administration will depend on the drug to be used, the severity of the pain and the likely side effects. Drugs are best given by mouth if possible but the rectal route may be tolerated better if vomiting is a problem. The parenteral route (by injection) should only be used if the drug selected can only be given by that method or where other methods have failed. Intramuscular injections should be avoided as they may be very painful themselves and subcutaneous or intravenous routes are to be preferred. Local anaesthetic creams are available that can be applied under an occlusive dressing to produce anaesthesia of the underlying skin for up to an hour. These may enable painless placement of venous catheters or allow infiltration of the area with local anaesthetic. These creams should not be used rectally, directly on the wound or on mucous membranes. Many procedures associated with the relief of pain can themselves be painful. The performance of regional blockade, wound infiltration and the placement of intravenous or subcutaneous lines and catheters may be carried out without discomfort or resistance whilst the patient is anaesthetised. Infiltration of local anaesthetic agent into the wound before wakening can reduce postoperative pain for long periods. Equally, regional anaesthesia undertaken while the child is under general anaesthesia can give prolonged control of pain and avoid the use of opioids. It is particularly suitable where early discharge from hospital is required. Extradural anaesthesia by the caudal route will provide excellent analgesia for any surgery below the waist such as herniorrhaphy, orchidopexy or circumcision. Children and their parents should be warned of the possibility of urinary retention and of transient weakness or numbness. Hypotension does not seem to be a problem in children under the age of six, but can be anticipated in older children and adults. Dose schedule for caudal block with bupivacaine in children. 0.25% solution is satisfactory for blocks requiring a volume of 20ml or less. A more dilute solution (0.2% bupivacaine) should be used where volumes of 20 ml or more are required. For short cases 1% lignocaine will be effective and the required volume can be calculated in a similar fashion. Type of block Volume (ml/kg) Lumbosacral 0.5 Thoracolumbar 1.0 Mid-thoracic 1.25 Maximum doses of bupivacaine in any four hour period are 2-3mg/kg and for lignocaine 3mg/kg (without adrenaline), 6mg/kg (with 1:200,000 adrenaline) Non-opioid analgesics Paracetamol is effective for mild to moderate pain. It can be given as an oral suspension in a dose of 15mg/kg to a maximum of 60mg/kg in 24 hours. Slightly higher doses (20mg/kg) are needed if this drug is used rectally as absorption is less reliable. NSAIDs Aspirin should not be given to children under 12 years old because of the association with Reye's syndrome. There is little experience with the use of NSAIDs in children except in the case of ibuprofen. This is available as a suspension or a syrup and should be given up to a dose of 20mg /kg/day. Diclofenac is available as a suppository (12.5mg or 25mg) for paediatric use and can be used as a premedicant or administered at induction of anaesthesia. Dosage can be up to 3mg/kg/day. Opioids Opioids can be used in the same way for children as for adults. The chief concern is that of respiratory depression when larger doses are being used. Suggested dose guidelines given here will minimise the possibility of this and yet still give effective pain relief. Codeine is effective by mouth for mild to moderate pain and is usually taken in combination with paracetamol. Caution is needed when using this drug with neonates who may be more liable to respiratory depression. Codeine can be given by subcutaneous or intramuscular injection to provide pain relief for babies or children who are outpatients. Doses are similar whichever route is chosen. Codeine is effective when given by suppository. However, children between the ages of 2 and 12 may not always appreciate the virtues of giving the drug by this method. Codeine is not suitable for intravenous use as it can produce severe falls in blood pressure and apnoea. Doses of codeine syrup range from 0.5-1mg/kg 4 hourly given orally or by intramuscular injection. Codeine given as a suppository: 1mg/kg 4 hourly. Morphine is the drug of choice for children who are inpatients. The preferred route of injection is intravenous but other routes can be used. Intramuscular injection is painful and unpopular with patients and nurses, however, this route may be used during the operation to provide analgesia at the time the child awakens from anaesthesia. The subcutaneous route can be useful when venous access is difficult. Intravenous morphine is painless once access has been established and if an infusion is to be used the same precautions must be taken to prevent accumulation as were outlined earlier. Normally a loading dose is infused over 30 minutes followed by a background infusion, titrated against the child's pain and the presence of side effects. If staff are experienced in looking after children postoperatively, there is no need for high dependency or intensive care facilities whilst these techniques are employed. Doses of morphine orally are 200-400mcg/kg 4 hourly. Subcutaneous or intramuscular routes 100-150mcg/kg 4 hourly. Intravenous doses 50-100mcg/kg over 30 minutes as a loading dose and then 5-40mcg/kg hourly. Children as young as five years can use PCA satisfactorily. This is one of the rare circumstances where a background infusion may be of some benefit, as children rarely remember preoperative instructions immediately upon waking. Great care must be taken to ensure that parents do not use the device on behalf of the child. PCA may be of value when dealing with other acute pains such as may accompany sickle cell crisis or the mucositis associated with chemotherapy. PCA Doses: background infusion 4mcg/kg/h. Additional doses 10-20mcg/kg and a 5-15 minute lock -out. A four hour dose limit is advisable and should be calculated after the patient's response is assessed (usually around 400mcg/kg). Intrathecal and epidural opioids have been used in children. There is a very high incidence of nausea and vomiting, itching, urinary retention and late (up to 24 hours) respiratory depression. Although analgesia is good, the potential for unpleasant and serious side effects limits the use of these approaches in children. Pain relief in the elderly The elderly also present special problems in the provision of analgesia. There may be great difficulty in communication and assessment and the choice of analgesic techniques should reflect this. As a general rule the elderly report pain less frequently and require smaller doses of analgesic drugs to achieve adequate pain relief. Many patients are anxious, however, and this may correlate with increased pain postoperatively. Assessment of pain may be carried out by normal methods and conventional numerical or graphical methods work well. However, impairment of higher intellectual functions may mean that observational techniques similar to those described earlier be needed. When analgesic drugs are given they may not be absorbed as well or metabolised as efficiently. In practical terms, doses of drugs such as NSAIDs and opioids should be reduced because of a decrease in liver metabolism. In addition, since the metabolites of drugs such as morphine and pethidine are excreted by the kidneys, any decrease in renal function may lead to accumulation with repeated doses. The elderly are more likely to be receiving more than one drug for underlying medical conditions and the possibility of drug interaction is greater (see *INFO* Table 7). Local anaesthetics. Nerve blocks are a most effective way of giving postoperative pain relief. Intercostal nerve block can aid pulmonary function after chest or upper abdominal surgery and pain below the waist can be abolished by epidural blockade aiding the return of gastrointestinal function after surgery. However, blocks spread more widely in the elderly and there may be compromise of respiratory function due to intercostal paralysis. In addition, a greater sympathetic block may occur with a consequent fall in blood pressure. With care, local anaesthetic blocks can be very useful in the elderly and give excellent pain relief whilst permitting mobilisation and rehabilitation. NSAIDs are often undervalued. However, gastrointestinal disorders are more common and care should be taken in patients with compromised hepatic or renal function. Opioids. Self-medication with opioids is not always wise in elderly patients and thus the role of PCA may be limited. It is probably better to use conventional intravenous and intramuscular methods of delivery which will give an immediate effect which can be assessed by those caring for the patient. The elderly may be particularly sensitive to opioids and side effects such as confusion, sedation and respiratory depression assume greater importance. Because of changes in hepatic and renal function lower doses of opioids are needed and the expected length of action may be longer. Only one drug should be used at a time. In general about half the normal adult dose should be given at first, especially if the drug is being given intravenously. Small doses should be given regularly to anticipate pain where appropriate. Pain from other Acute Causes Many of the principles of pain relief contained in this survey apply to the management of other pain conditions; burns and trauma are obvious examples. A difference is that pain as a symptom may last longer than when seen in association with surgery. The initial pain of the injury will require treatment in the normal fashion, but there are subsequent phases of healing and rehabilitation which may be long and painful. The healing phase may take many weeks depending upon the nature of the injury and the length of the rehabilitation phase. It is important to provide adequate analgesia for the performance of procedures such as dressings, physiotherapy and skin grafts. Emotional consequences and tissue damage from the burn or injury, such as nerve damage, may require additional treatment. In these circumstance use of short-acting drugs is inappropriate. In addition, it is better to establish regimens of regular pain relief. Combined techniques to address all aspects of the pain problem are best carried out by a multidisciplinary team. * Identify the parameters measured by the pulse oximeter. * Discuss the interpretation of pulse oximetry in clinical disease. * Discuss the utility of pulse oximetry in field clinical decision making. * Discuss hyperventilation syndrome and triage decisions regarding tachypnea. * Discuss toxicologic emergencies influencing pulse oximetry. As with anything relatively new, once a procedure or guideline or a piece of equipment is out in operation for a while questions come up that may not have been anticipated or experiences occur that need some clarification. Since we implemented pulse oximetry some time ago several questions representing common themes have come up. This is a good time to revisit some of the key points of field pulse oxmitery, answer some of the commonly asked questions and review some of the basics. What exactly does the pulse oximeter measure? Blood carries oxygen in two forms, the majority is bound to hemoglobin (oxyhemoglobin) and the rest is dissolved in the aqueous phase of blood (the plasma). The pulse oximeter measures the saturation of hemoglobin with oxygen. This is expressed as a percent saturation. Each gram of normal hemoglobin can hold 1.34 milliliters of oxygen. Well talk about hemoglobins later. The dissolved fraction is dependent upon the partial pressure of oxygen. As the partial pressure increases, the dissolved fraction of oxygen increases. Fore each 1mmHg pressure of oxygen partial pressure0.003 milliliters dissolves in the plasma. So under normal conditions each 100-ml of blood contains about 20 ml of oxygen bound to hemoglobin and about 0.3 ml dissolved in plasma, The dissolved fraction is available to tissues first, and then the fraction bound to hemoglobin. So as tissues metabolize oxygen, or if oxygen becomes difficult to pink up through the lungs the dissolved oxygen and the hemoglobin bound oxygen will eventually become depleted. The dissolved oxygen can be measured by arterial blood gas analysis but this is not yet practical for field application. This fraction is not measured by pulse oximetry. The pulse oximeter waits to sense the pulse of capillary blood from side of the capillaries, then using two different wavelengths of light calculates the percent of oxyhemoglobin from the total hemoglobin present. If oxygen transfer across the lungs or lung function is compromised and as tissues continue to metabolize oxygen, the percentage of oxyhemoglobin will decrease. This becomes our quantitative indicator of hypoxia. If the pulse oximeter indicates normal saturation, does oxygen still need to be administered? The use of pulse oximetry is not intended to be a means of justifying the withholding of oxygen and related appliances to save money. As contrary to the fire service mission as they may sound, in the modern climate of cost- conscious-at-the expense of the patient medical practice it should at least be said once. Once hemoglobin is saturated with oxygen, administration of additional oxygen will not put more oxygen on the hemoglobin molecules. However, the fraction of total blood oxygen we still have control over is the dissolved fraction in the plasma. As the percentage of inspired oxygen is increased by nasal cannula, simple facemask or non-re breather mask, the partial pressure of oxygen increases. As partial pressure increases the amount of dissolved oxygen increases. So, even at 100% hemoglobin saturation we can increase the oxygen carrying capacity of the blood somewhat by increasing the percent of inspired oxygen. Fore example, using a non- re breather facemask delivering better than 90% inspired oxygen would increase the dissolved fraction of oxygen in the blood plasma from 0.3ml per 100 ml blood to about 1.8 ml or a six- fold of about 1.5% of the total available oxygen, use of the non re breather facemask increases that fraction to about 8.0%. Our goal is to improve oxygen deliver to tissue. Oxygen delivery to tissues or organs depends on four things: hemoglobin concentration, hemoglobin oxygen saturation, dissolved oxygen in plasma and tissue perfusion. We cant increase the hemoglobin concentration, although the future of blood substitutes may make this concept possible. If lung function and perfusion is reasonably normal the hemoglobin saturation with oxygen should also remain normal, especially with supplemental oxygen administration. If it is abnormal supplemental oxygen and other airway maneuvers will increase it as much as possible. Supplemental oxygen will increase the dissolved oxygen fraction in the blood. Even though this is the minority of available oxygen, this extra small fraction may be helpful to ischemic tissue. We can assist tissue perfusion by increasing intravascular volume (IV saline), vasodilating critical vascular beds (nitroglycerin) and improving cardiac output (nitroglycerin, dopamine). The answer whether or not to administer supplemental oxygen when oxygen saturation is normal (95% or greater) depends on the problem you think you are treating. Lets take the common example of chest pain with suspected angina or myocardial infarction (or acute coronary syndrome, as it have been known). If there are no underlying lung problems and if heart function is not so badly effected as to seriously compromise cardiac output and reduce lung perfusion, the oxygen saturation of hemoglobin would be expected to be normal. But the heart muscle downstream from the coronary artery obstruction is ischemic. The strategy of treatment is to increase oxygen delivery to that ischemic muscle. One approach is to give nitroglycerin to dilate some coronary vessels to increase blood flow. But administering supplemental oxygen will also increase oxygen delivery. So, increasing oxygen delivery to suspected ischemic organs or tissue is the rationale behind supplemental oxygen despite a normal pulse ox. Another common example is closed head injury. Brain swelling and neuronal disruption can lead to reduced cerebral perfusion. Supplemental oxygen will increase oxygen delivery to injured brain by increasing the dissolved oxygen blood. Maintaining adequate perfusion (avoiding hypotension) is another early goal in the management of brain injury. A similar strategy applies to stroke. Head injury and stroke are examples through where the primary injury may also affect respiration. If respiration is aversely affected by the brain injury the pulse ox along with clinical signs may be an early indicator of hypoxia. So, when should supplemental oxygen be administered despite a normal pulse ox? Whenever the underlying problem is suspected to be organ or tissue ischemia. This would include things like: stroke, intracerebral bleed, head injury, altered mental status from any cause, chest pain of suspected cardiac origin, cardiac dysrhythmias, shortness of breath from any cause, vascular emergencies like aortic dissection or aneurysm or vascular occlusions, shock from any cause, sickle cell disease and multisystem trauma. So how does pulse oximeter help make triage and treatment decisions? The primary utilities of the pulse oximeter are to determine the relative severity of cardiopulmonary or airway disease, monitor the effectiveness of therapy and monitor for deterioration in condition. As we see from the above discussion normal hemoglobin saturation is good news but not the end of the story. Symptoms or signs of potential organ ischemia will still determine the need for supplemental oxygen. An abnormal hemoglobin saturation is more useful to guide us in what to do next. Mild to moderate hypoxia is presented by a pulse ox of 90-95%. Moderate to severe hypoxia is represented by a pulse ox of 80-90%. Severe hypoxia is anything less then 80%, although the accuracy of pulse oximetry decreases generally below about 70%. Also, when trying to interpret very abnormal pulse oximetrey readings check to see if the pulse rate recorded by the pulse ox correlates with a palpated or ECG monitor rate. So, a pulse ox value in the 80s for a child with an asthma exacerbation or in a person with congestive heart failure may prompt us to move from less aggressive therapy to more aggressive therapy more quickly. This may mean choosing continuous albuterol over a single or spaced intermittent albuterol in the case of pediatric asthma or using sequential double dose nitroglycerin, morphine, albuterol and possibly positive pressure ventilation in the case of pulmonary edema. If a more conservative route of therapy is tried monitoring for deterioration may change the strategy. Hopefully as treatment progresses there will be both clinical improvement in the patients condition as well as improvement in vital signs, which includes pulse oimetry. In the case of narcotic overdose, the strategy for reversal with naloxone has changed over the years. In the past we used to wake them all up, much to our dismay as well as theirs in many cases. Now we rely on respiratory assessment to determine when reversal is necessary. With adequate respiration it is generally safer to allow the effects of the narcotic to resolve under constant monitoring. Assessment of adequacy of respiration usually is left to determining respiratory rate and depth. The observation of a normal pulse ox is additional data to support the lack of clinical grounds for narcotic reversal. Conversely hypoxia by pulse ox would argue for reversal with titrated doses of naloxone What respiratory function will pulse ox not measure? The pulse oximeter measures oxygenation. It does not measure ventilation. Ventilation is the process of removing carbon dioxide from the blood. Hypoventilation from any cause will result in the accumulation of carbon dioxide in the blood. This leads to respiratory acidosis. If hypoventilation goes on long enough blood oxygen will begin to deplete and the pulse oximeter oxygen saturation will begin to decrease. However, short of apnea the rate of carbon dioxide accumulation and the development of respiratory acidosis may be greater then the rate of onset of hypoxia by pulse oximetery. The assessment of adequate ventilation is based on respiratory rate and depth. Should I hold on administering oxygen in order to check a baseline pulse ox? The decision to administer supplemental oxygen is based on available history and initial examination. If your first impression is that the patient is really sick, then they probably are. So dont feel compelled to document a baseline pulse ox in a patient you think is in trouble. If the flow of the call results in an off oxygen pulse ox reading being available it certainly can be useful to correlate to symptom severity, but dont hold off on oxygen waiting to get this value. Where this might be useful is the patient who is symptomatic and looks OK for the moment, but you would like to get a better assessment of the severity of the symptoms. For example, in pediatric asthma where there is wheezing but no intercostal retractions or other assessory muscle use a pulse ox on ambient air of say 94% would be reassuring. But if the pulse ox is 84%, tells you that this child is compensating for the moment but is still quite hypoxic. This might lead to a more aggressive approach to treatment or even give the treating emergency department some insight into the severity of the attack before field treatment if they are undecided ultimately about admission or discharge. In general, this approach may have some value in children with apparently stable respiratory symptoms since kids tend to compensate longer than adults and an initial ambient air pulse ox reading may give you some idea about the severity of the problem. Can pulse oximetry help diagnose hyperventilation syndrome? Unfortunately, no. What pulse oximetery can do for you though is identify the absence of hypoxia as a cause of the trachypnea. The challenge is assessing a person with rapid, deep breathing and anxiety is that there are a few serious disease that can look like an anxiety reaction and hyperventilation syndrome should have some reasonable identifiable proximate cause for its onset. The muscle cramps in the hands and feet are caused by the very low blood carbon dioxide content, which leads to respiratory alkalosis. This alkalosis lowers the solubility of calcium in the blood and calcium concentration falls. The low blood calcium causes skeletal muscle to misfire, which is seen in the smaller muscles of the hands and feet first. Causes of tachypnea include the general categories of sepsis, hypoxia, acidosis and brain, lung and heart disease. Its not practical to list all the causes of trachypnea. But major causes, things we dont want to miss, include injury, pneumonia, pulmonary embolism, heart failure, and metabolic acidosis. Important causes of metabolic acidosis are diabetes, uremia (kidney failure) and toxicants like ethylene, glycol, methanol, iron and salicylates (aspirin) Triage decisions involving trachypnea will largely be based on the history of the problem. An anxiety reaction should begin to improve with support., reassurance and removal of the proximate cause if possible. Rebreathing exhaled air from a bag, or applying an oxygen mask without flowing oxygen will not address the underlying problem causing the anxiety reaction and shouldnt be tried. The old idea of rebreathing exhaled air was aimed at increasing blood carbon dioxide levels to correct the muscle cramps. Controlling respiratory rate and depth by support and reassurance will accomplish the same thing. However, while this decision process is going on and other causes of tachypnea are being sought through history and examination, administering supplemental oxygen will not worsen true hyperventilation syndrome. Remember it is the low blood carbon dioxide concentrates that lead to the muscle cramps. Supplemental oxygen will not affect hyperventilation syndrome and should be administered until the cause of the tachypnea can reasonably be determined. If these efforts to identify and correct the tachypnea fail and the tachypnea persists then we have an abnormal vital sign that will require further evaluation. Wasnt there something about abnormal hemoglobins? Ah uncommon but important limitation of pulse oximetry is the presence of abnormal hemoglobins. Most likely is carbonhemoglobin. Carbon monoxide poisoning results in binding of carbon monoxide to hemoglobin and other cellular oxygen transport proteins (cytochromea3). The light wavelengths used to measure oxyhemoglobin cannot differentiate it from carboxyhemoglobin so the pulse oximeter can read normal hemoglobin saturation despite significant hypoxia. Usually circumstances surrounding the call will suggest a toxic inhalation: structure fire, attempted suicide using internal combustion engine exhaust, interior use of charcoal grills for cooking or heating, malfunctioning fossil fuel heaters. Malfunctioning heaters can be a subtle source of mild to moderate chronic or intermittent carbon monoxide poisoning or can lead to a muti- victim toxicologic incident. An unusual source of carboxyhemoglobin is methylene chloride poisoning, a component of some degreasers, carburetor cleaners and paint strippers. Inhalation of methylene chloride vapor or ingestion of the liquid (or skin absorption too potentially) leads to the metabolism of the methylene group to carbon monoxide. Although controversial, a victim of carbon monoxide poisoning who is or was unconscious, has an altered mental status, is hypoxic, has dysrhythmias or is pregnant should probably be transported to a hospital with hyperbaric oxygen capabilities. In Orange County these are Western Medical Center Santa Ana, and Hoag Memorial Presbyterian. Other cases of carbon monoxide poisoning can be treated and transferred. Other less likely toxicologic exposures that result in abnormal hemoglobins are nitrites, anilines, nitrobenzene and nitroglycerine that cause methemoglobinemia and hydrogen sulfide, a potential atmospheric contaminant in confined space operations, that causes sulfhemoglobinemia. In the case of methemoglobin, the iron in oxyhemoglobin is abnormal hemoglobin and will give a falsely low reading despite oxygen administration. Information available at the incident may help to identify these possibilities. What is critical care? What kinds of illness and injury usually require critical care? What is the difference between critical care and emergency medicine? What is an intensivist? How does a family physician fit into the team? What resources are available when facing end-of-life (EOL) decisions? How can I obtain copies of living wills and other documents? What is critical care? Critcal care is the multiprofessional healthcare specialty that cares for patients with acute, life-threatening illness or injury. Nearly 80 percent of all Americans will experience a critical illness or injury, either as the patient, family member or friend of a patient. Critical care can be provided wherever life is threatened - at the scene of an accident, in an ambulance or medivac helicopter, in a hospital trauma center or emergency room, or in the operating room. Most critical care today, however, is delivered in highly specialized intensive care units and trauma centers. Critical care is provided by multiprofessional teams of highly experienced and professional physicians, nurses, respiratory care technicians, pharmacists and other allied health professionals who use their unique expertise, ability to interpret important therapeutic information, access to highly sophisticated equipment and the services of support personnel to provide care that leads to the best outcome for the patient. Patients are rarely admitted directly to the critical care unit. Rather, they are usually admitted from the emergency room, trauma center or surgical area where they are first given care and stabilized. The continuum of critical care begins at the moment of illness or injury and continues throughout the patient's hospitalization, treatment and subsequent recovery. What kinds of illness and injury usually require critical care? Typical examples of critical illness include heart attack, poisoning, pneumonia, surgical complications, premature birth, and stroke. Critical care also includes trauma care - care of the severely injured - whether due to an automobile accident, gunshot or stabbing wounds, a fall, burns, or an industrial accident. What is the difference between critical care and emergency medicine? Critical care refers exclusively to the treatment of patients who suffer from life-threatening conditions. Emergency room physicians and nurses treat patients who suffer from relatively minor emergencies (sprained ankles, broken arms) to those with major problems including heart attack, knife or gunshot wounds or drug overdoses. In the Emergency Department, physicians and nurses stabilize patients and transport them to the ICU or other area of the hospital for further treatment. The long-term management of critically ill and injured patients is provided by critical care professionals, often in the ICU. What is an intensivist? An intensivist is a physician with subspecialty training, or equivalent qualifications, in critical care. An intensivist directs the care of critically ill and injured patients and works in collaboration with other health care professionals necessary for the care of patients in critical care units. How does my family physician fit into the team? Your family physician is an important link between the critical care team and the patient and family. The family physician has a complete medical history of the patient, is often a trusted confidante of the family and is may be aware of the patient's values, attitudes and health care preferences. Critical care teams often work closely with the family physician to determine pre-existing illness, allergies, use of medications, and other factors which may influence the health of the patient. What resources are available when facing end-of-life (EOL) decisions? The Society provides resources that are relevant to end-of-life decisions to assist critical care providers, patients and their families during these difficult situations. We encourage you to ensure that your own wishes are adequately documented in the advent that you are not able to personally direct your own care. * The Society recently produced the Compassionate Care in the ICU DVD that initially was sent to all SCCM members. The professional version went to individual SCCM members, and the family version was sent to ICU directors. If you need an additional copy of these DVDs please contact SCCM Headquarters at +1 (847) 827-6888. Supplies are limited. Watch the Family Version of the Video Presentation online The Societyâs ICU Issues and Answers brochure on "What Are My Choices Regarding Life Support?" is available free online and also available in printed copy through the SCCM catalog and online store. Of note, additional online information for personal advanced care planning is available from the National Hospice & Palliative Care Organization (www.caringinfo.org). * The Society's American College of Critical Care Medicine (ACCM) previously published Recommendations for End-of-Life Care in the ICU, which is available here. * The Society also has participated in the process to establish practice parameters on the Assessment and Management of Patients in the Persistent Vegetative State issued by the American Academy of Neurology. A copy of these parameters, along with an ethics statement, is available online. Society members were major participants in a Robert Wood Johnson Foundation research grant that focused on end-of-life care. The outcomes for this report is published: Quality indicators for end-of-life care in the intensive care unit (Crit Care Med 2003; 31: 2255-2262). The complete article is available here as a PDF file, and an accompanying editorial written by the 2005 SCCM President is also available here. * Challenges in end-of-life care in the ICU: statement of the 5th International Consensus Conference in Critical Care: Brussels, Belgium, April 2003 included major contributions by SCCM members and was published in Critical Care Medicine: (Thompson BT, Cox PN, Antonelli M, et al executive summary. Crit Care Med. 2004; 32:1781-1784). A copy is also available as a PDF file here. How can I obtain copies of living wills and other documents? When your loved one is in the ICU, what can you do to help? Participating in Care: What Questions Should I Ask? Interacting with the intensive care team The intensive care unit is a busy, noisy environment. There are many alarms, monitors, and devices. Watching everything that happens here may raise many questions. This brochure is meant to help guide your questions to the members of the ICU team. The doctors, nurses, therapists, and other staff are here to answer your questions. There are no wrong questions. Stress makes it difficult to understand and remember unfamiliar information. It is okay to ask questions more than once. If you are unsure of what to ask, here are some questions that may address the most common areas of concern. What should I say to my loved one? You should speak normally. However, keep in mind that the patient might not be able to respond to you, either because there is a breathing tube in place that does not allow the patient to speak, or because of medications or altered awareness. You should still speak with the patient even if he or she is in a disoriented state or coma. If the patient is alert, and has a breathing tube in place, phrase questions that can be answered with yes or no nods. If he or she is able, help write brief answers on a pad of paper. Occasionally, over-stimulation may temporarily affect vital signs unfavorably. The nursing staff will instruct you on how you can be supportive in other ways. Is it okay to touch my loved one? Yes. Touching is usually comforting. The nursing staff will let you know if this is interfering with rest or care. How long should I visit? Familiarize yourself with the visiting hours policy of the intensive care unit. In general, you need to visit as long as it is helpful. The nursing staff can often help you with this decision. Both you and your loved one need rest, quiet time, and nutrition. Poor nutrition and lack of sleep will make you weak, able to think less clearly, and feel the effects of stress more strongly. In the case of young children in the ICU, having a familiar person present or near at all times may be helpful. However, one person cannot usually do this. Therefore, having other family members or close friends who can take turns being with your child is ideal. Should I bring anything from home? Familiar things are often comforting; however, you should check with the nurse before bringing anything into the ICU. Photographs, cards, pajamas, robes, and slippers may be helpful. Children may have a favorite stuffed animal or blanket. Many ICUs may have the capability to play favorite music or videos. Friends and family members who are unable to visit may send an audio recording of well wishes. What should I ask the nurse? The nurse has the benefit of being at the bedside for an extended period of time. Therefore, he or she may be the best person to comment on the patient's comfort and response to certain therapies. Here are some questions that should generally be asked of the nurse: . Who are the doctors who are caring for my loved one? . Which doctor is in charge? . Is there an intensivist (a doctor with special expertise in critical illness) involved in the care of my loved one? . Is there anything in the treatment plan for the day that may be painful or uncomfortable? . If so, have medications been ordered to prevent this? . If you are not in the room, how do I call for help? . How quickly should I expect someone to respond to the call? . How does my loved one go to the bathroom? . Can you explain to me what the doctor said? . Will you explain what all the lines, tubes, and equipment are and what they do? . What can I do to help? . What can I do to help my family and myself? . Who can visit and when? . If I am not in the hospital and something happens, how will you get in touch with me? . What happens if something urgently happens and I am not available? What should I ask the doctor? When you do speak with the doctor, it is often difficult to remember all your questions. Therefore, writing down questions and concerns as they arise can be helpful. Here are some commonly asked questions: . What is wrong with my loved one? . Can it be cured? . How will this condition affect his or her quality of life? . What is the treatment plan? . When do you usually see a response? . What changes will you be watching for as a response to the therapy? . What are the risks of the therapy and/or medications? . Is the patient in any pain? . What is being done to ease pain and fear? . How is nutrition provided? . Is the patient receiving the medications he or she was on at home? How often should I get information? In general, daily discussions with critical care team members allow for an update on the condition of your loved one and the treatment plan. If an acute change or event occurs, you may need to speak with the doctor more frequently. The bedside nurse is very helpful in keeping you updated about events of the day as well as clarifying information. If there are multiple physicians, selecting one of them to speak to the family daily can often be less confusing. In addition, it is often best to have 1 or 2 family members serve as the spokesperson(s). In case of difficult decision-making and/or confusing information, the nurse or social worker can often arrange a "team meeting" or a private meeting with the doctor. What is the best way to share information with family and friends? Many family members and friends will be anxious to hear how your loved one is doing. They will want to know what is wrong, how the patient is responding, and what they can do to help. Their concerns can be of comfort, but sometimes seem overwhelming as you try to make contact with everyone. First of all, if there are needs at home or work that others can help you with, let them. This is helpful to you as well as to the person helping. In regard to relaying medical information, you must first decide whom you want to relay this information to and what information you want to share. Once you have decided this, it is often helpful to pick 1 or 2 family members or friends to be in charge of getting this information to others. The person or persons that you choose must be able to understand the medical condition correctly so as to prevent miscommunication. These persons can also "filter" out all the free advice that friends and family members might offer. To protect patient privacy, information may be restricted to the family spokesperson. What is meant by "doing everything"? "Doing everything" implies that any and all appropriate therapies will be utilized in order to preserve life. This can include the use of life support machines, dialysis, invasive monitors, and CPR in the event of cardiac arrest. Physicians are not required to offer therapies that would be medically ineffective (will not increase the patient's chances of survival), and you may be told that your loved one is not a candidate for certain interventions. Intensivists (trained intensive care doctors) can help by addressing your loved one's care with you. If the medical condition is not curable or recovery is unlikely, what are the options for comfort care? The medical team can discuss all the options with you and your family. Your options may include removal of certain therapies like mechanical ventilation, medications to support heart function, dialysis, etc. Certain tests and procedures that are not likely to be helpful can also be discontinued. Some questions to clarify this can include: . What does "DNR" mean? . Will CPR save the patient's life if his or her heart stops? . How will the patient be kept comfortable? . Could the patient go home or have hospice care? . In cases that involve children-Can I hold the patient? . Can our clergy come? . Can you wait to remove certain life-supporting equipment or therapies until after all family members and friends have had a chance to say good-bye? What if I want everything done, but the medical staff feels stopping or not adding certain therapies is more appropriate? This situation usually arises if there has been a poor understanding of the current medical condition and/or the benefits of certain therapies. If this conflict does arise, then a meeting of appropriate family members and medical staff should occur. At this meeting, a treatment plan can usually be agreed upon. In the rare occasion that a treatment plan cannot be agreed upon, most hospitals have an ethics committee that can be contacted to get involved in the decision-making. What is a Neonatologist? What kind of training do neonatologists have? What types of treatments do neonatologists provide? |