Monitor vital signs frequently every two to five minutes and stay with the patient. Administer epinephrine , weight-based adults: 0. Administer oxygen, usually 8 to 10 L per minute; lower concentrations may be appropriate for patients with chronic obstructive pulmonary disease. Administer the antihistamine diphenhydramine Benadryl, adults: 25 to 50 mg; children: 1 to 2 mg per kg , usually given parenterally. If anaphylaxis is caused by an injection, administer aqueous epinephrine, 0.
If hypotension is present, or bronchospasm persists in an ambulatory setting, transfer to hospital emergency department in an ambulance is appropriate. Treat hypotension with IV fluids or colloid replacement, and consider use of a vasopressor such as dopamine Intropin. Treat bronchospasm, preferably with a beta II agonist given intermittently or continuously; consider the use of aminophylline, 5. Give hydrocortisone, 5 mg per kg, or approximately mg intravenously prednisone, 20 mg orally, can be given in mild cases.
The rationale is to reduce the risk of recurring or protracted anaphylaxis. These doses can be repeated every six hours, as required. In refractory cases not responding to epinephrine because a beta-adrenergic blocker is complicating management, glucagon, 1 mg intravenously as a bolus, may be useful.
A continuous infusion of glucagon, 1 to 5 mg per hour, may be given if required. Although isoproterenol may be able to overcome depression of myocardial contractility caused by beta blockers, it also may aggravate hypotension by inducing peripheral vasodilation and may induce cardiac arrhythmias and myocardial necrosis. If a decision is made to administer isoproterenol intravenously, the proper dose is 1 mg in mL D5W titrated at 0.
Adults should be given approximately 50 percent of this dose initially. Cardiac monitoring is necessary and isoproterenol should be given cautiously when the heart rate exceeds to beats per minute.
Medical offices in which the occurrence of anaphylaxis is likely should consider periodic anaphylaxis drills. Protocols for use in schools to manage children at risk of anaphylaxis are available through the Food Allergy Network. These protocols include materials for educating teachers, office workers, and kitchen staff in the prevention and treatment of anaphylaxis. Furthermore, patients should be given written information with suggested strategies for their own care.
The diagnosis and management of anaphylaxis. Patients taking beta-adrenergic blockers present a special challenge because beta blockade may limit the effectiveness of epinephrine. These patients may have resistant severe hypotension, bradycardia, and a prolonged course. Atropine may be given for bradycardia 0. Glucagon exerts positive inotropic and chronotropic effects on the heart, independent of catecholamines. Therefore, glucagon, 1 mg intravenous bolus, followed by an infusion of 1 to 5 mg per hour, may improve hypotension in one to five minutes, with a maximal benefit at five to 15 minutes.
The U. Food and Drug Administration has not approved glucagon for this use. Nausea and vomiting may limit therapy with glucagon. All patients with anaphylaxis should be monitored for the possibility of recurrent symptoms after initial resolution. Laboratory testing may help if the diagnosis of anaphylaxis is uncertain. At discharge, the patient should be told to return for any recurrent symptoms. Some experts advocate a short course of antihistamines with oral corticosteroids e.
A patient with a history of anaphylaxis should be instructed on how to initiate treatment for future episodes using pre-loaded epinephrine syringes. Two strengths are available: 0. Training kits containing empty syringes are available for patient education. Family members and care-givers of young children should be trained to inject epinephrine. Written instructions should be given. The patient also may take an antihistamine at the onset of symptoms. The patient must be told to seek immediate professional help regardless of initial response to self-treatment.
If possible, the patient should avoid taking beta blockers, angiotensin-converting enzyme ACE inhibitors, angiotensin-II receptor blockers, and monoamine oxidase inhibitors, because these drugs may interfere with successful treatment of future anaphylactic episodes or with the endogenous compensatory responses to hypotension. Finally, the patient should be advised to wear or carry a medical alert bracelet, necklace, or keychain to inform emergency personnel of the possibility of anaphylaxis.
Prevention of future episodes is vital Table 6. This requires identification of the anaphylactic trigger, which is often difficult. The physician's primary tool is a detailed history of recent exposures to foods, medications, latex, and insects known to cause anaphylaxis. Previous tolerance of a substance does not rule it out as the trigger.
Despite a detailed history, a cause remains elusive in many patients. Direct skin testing and radioallergosorbent testing RAST are available for some antigens, including heterologous sera, Hymenoptera venom, some foods, hormones, and penicillin. Skin testing itself carries a risk of fatal anaphylaxis and should be performed by experienced persons only. Scratch and prick tests should precede intra-dermal testing to decrease the risk of an unexpected severe reaction. Penicillin skin testing includes major and minor determinants; the minor determinants are more predictive of future anaphylactic events.
However, it is limited to the same antigens that are available for skin testing. Both skin testing and RAST have imperfect sensitivity and specificity. Advise patient to wear or carry a medical alert bracelet, necklace, or keychain to warn emergency personnel of anaphylaxis risk. Advise patient to keep epinephrine self-injection kit and oral diphenhydramine Benadryl for future exposures.
Avoid prescribing beta blockers, angiotensin-converting enzyme inhibitors, angiotensin-II receptor blockers, monoamine oxidase inhibitors, and some tricyclic antidepressants. Refer to allergist if causative agent or diagnosis is unclear, if in-depth patient education is needed, or if reactions are recurrent. If re-exposure to an offending medicine is necessary, administer the questionable medicine orally and observe the patient for the following 20 to 30 minutes; consider pretreatment with steroids and antihistamines.
Consider desensitization if available. When there is no choice but to re-expose the patient to the anaphylactic trigger, desensitization or pretreatment may be attempted. Desensitization carries a risk of anaphylaxis and should be performed by experienced persons in a well-equipped location.
In this procedure, the patient is exposed to gradually increasing amounts of antigen, usually via intradermal, then subcutaneous, then intravenous routes. Immunotherapy is recommended for insect sting anaphylaxis, because it is 97 percent effective at preventing recurrent severe reactions.
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Mary Beth Wilhelm. Robert Houton. You might also be interested in…. Controlling Your Allergies Whether you get skin rashes, itchy eyes, wheezy airways, or a runny nose, an allergic response is no fun, and is sometimes dangerous.
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I want to get healthier. Matsui; Epinephrine for First-aid Management of Anaphylaxis. Pediatrics March ; 3 : e Anaphylaxis is a severe, generalized allergic or hypersensitivity reaction that is rapid in onset and may cause death. Epinephrine adrenaline can be life-saving when administered as rapidly as possible once anaphylaxis is recognized. This clinical report from the American Academy of Pediatrics is an update of the clinical report on this topic.
It provides information to help clinicians identify patients at risk of anaphylaxis and new information about epinephrine and epinephrine autoinjectors EAs. The report also highlights the importance of patient and family education about the recognition and management of anaphylaxis in the community.
Anaphylaxis is defined as a serious, generalized allergic or hypersensitivity reaction that is rapid in onset and potentially fatal. Clinical presentation and severity can vary among patients and in the same patient from 1 anaphylactic episode to another. Clinical criteria for anaphylaxis have been proposed and validated. These clinical criteria for the diagnosis of anaphylaxis have been validated in emergency department studies in children, teenagers, and adults. They have high sensitivity Foods, especially peanut, tree nuts, milk, eggs, crustacean shellfish, and finned fish, are by far the most common triggers of anaphylaxis in the pediatric population.
Cofactors that lower the threshold at which triggers can cause anaphylaxis include exercise, upper respiratory tract infections, fever, ingestion of nonsteroidal antiinflammatory drugs or ethanol, emotional stress, and perimenstrual status.
Epinephrine is the medication of choice for the first-aid treatment of anaphylaxis. Through vasoconstrictor effects, it prevents or decreases upper airway mucosal edema laryngeal edema , hypotension, and shock. In addition, it has important bronchodilator effects and cardiac inotropic and chronotropic effects. Delayed epinephrine administration in anaphylaxis is associated with an increased risk of hospitalization 22 and poor outcomes, including hypoxic-ischemic encephalopathy and death. Epinephrine can be life-saving when injected promptly by the intramuscular IM route in the mid-outer thigh vastus lateralis muscle as soon as anaphylaxis is recognized Table 1.
Epinephrine autoinjectors EAs can be used in health care settings to deliver a 0. Adapted from refs 1 , — 3 , 6.
Note that only a few anaphylaxis symptoms may be present during an episode. Also, symptoms can differ among patients, and even in the same patient from 1 episode to the next. Typically, more than 1 body organ system is involved. If the response to the first epinephrine injection is inadequate, it can be repeated once or twice at 5- to minute intervals. Subsequent doses are typically given by a health care professional along with other interventions.
The need for subsequent injections did not correlate with obesity or overweight status. Subsequent epinephrine doses are needed for severe or rapidly progressive anaphylaxis and for failure to respond to the initial injection because of delayed injection of the initial dose, inadequate initial dose, or administration through a suboptimal route.
Food-induced anaphylaxis is associated with biphasic anaphylaxis less often than is venom- or drug-induced anaphylaxis. Reluctance to inject epinephrine promptly at the onset of anaphylaxis symptoms is best overcome by awareness that the severity of an anaphylactic episode can differ from 1 patient to another and in the same patient from 1 episode to another.
These effects cannot be dissociated from the beneficial effects of epinephrine. Epinephrine given by IM injection achieves peak concentrations faster than that given by subcutaneous injection.
There is no absolute contraindication to epinephrine treatment in anaphylaxis. Only 2 premeasured, fixed doses of epinephrine, 0. These doses are optimal for many children but not necessarily for all children. The 0. However, dose preparation can take laypersons as long as 3 to 4 minutes; moreover, doses typically are inaccurate and can sometimes contain no epinephrine at all when the solution is ejected from the syringe along with the air.
After consideration of the aforementioned alternatives that potentially lead to delay in dosing, incorrect dosing, or no dose at all and consideration of the favorable benefit-to-risk ratio of epinephrine in young patients with anaphylaxis, many physicians recommend the use of the 0.
On the basis of a pharmacokinetic study 40 and expert consensus, it is appropriate to switch most children from the 0. Most anaphylaxis deaths occur in community settings rather than in health care settings 1 , 16 , — 18 ; yet, some physicians fail to prescribe EAs for their patients at risk of anaphylaxis in the community.
In fact, some experts have suggested that consideration be given to prescribing EAs for all patients with immunoglobulin E—mediated food allergy, because it is difficult or impossible to predict the occurrence or severity of future reactions. Guidelines recommend prompt epinephrine injection for the sudden onset of any anaphylaxis symptoms after exposure to an allergen that previously caused anaphylaxis in that patient.
Even physicians with years of experience in diagnosing and treating anaphylaxis cannot determine, at the onset of an episode, whether that episode will remain mild or escalate over minutes to become life-threatening. It is therefore important that physicians instruct patients and caregivers to err on the side of prompt epinephrine injection. Many patients and caregivers fail to carry EAs consistently or to use them when anaphylaxis occurs, even for severe symptoms, including throat tightness, difficulty breathing, wheezing, and loss of consciousness.
Many parents fear using an EA because they worry about hurting or injuring their child or a bad outcome. Patients and caregivers need training in how to recognize anaphylaxis and use an EA. Epinephrine injections can be given through clothing, although care must be taken to avoid obstructing seams or items in pockets. Before using epinephrine, read the accompanying patient information, which includes step-by-step instructions for injection.
Epinephrine should be injected into the middle of the outer side of the thigh. In an emergency situation, epinephrine can be injected through clothing if necessary. Do not administer epinephrine to any other part of the body, including the:. A second dose of epinephrine should be injected if the initial anaphylaxis symptoms do not improve after 10 minutes of the first treatment.
Due to the severity of anaphylaxis, it is critical that people with serious allergies keep their epinephrine injection device with them or accessible at all times. Epinephrine should be injected as soon as you suspect you may be experiencing anaphylaxis symptoms. After injecting a dose of epinephrine, some solution will remain in the injection device. This is normal and does not mean that you did not receive the full dose. Take the used device with you to the emergency room or ask your doctor or pharmacist how to dispose of used infection devices safely.
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