Epinephrine absorption in children with a history of anaphylaxis

Epinephrine: the drug of choice for anaphylaxis-a statement of the world allergy organization

Anaphylaxis is an acute and potentially lethal multisystem allergic reaction. Most consensus guidelines for the past 30 years have held that epinephrine is the drug of choice and the first drug that should be administered in acute anaphylaxis. Some state that properly administered epinephrine has no absolute contraindication in this clinical setting. A committee of anaphylaxis experts assembled by the World Allergy Organization has examined the evidence from the medical literature concerning the appropriate use of epinephrine for anaphylaxis. The committee strongly believes that epinephrine is currently underused and often dosed suboptimally to treat anaphylaxis, is underprescribed for potential future self-administration, that most of the reasons proposed to withhold its clinical use are flawed, and that the therapeutic benefits of epinephrine exceed the risk when given in appropriate intramuscular doses.

Peanut and tree nut allergy in childhood

Peanut and tree nut allergies present multiple challenges in their presentation and management. These challenges have become increasingly relevant in recent years, as these allergies appear to have become more common. An estimated 1-2% of the population in the USA is allergic to peanut or tree nuts. Peanut allergy typically presents with symptoms in one of the first few exposures to peanut. Diagnosis is based on clinical history along with skin prick test, or quantitation of allergen-specific immunoglobulin E (IgE), and oral food challenges when indicated. Once the diagnosis is confirmed, the only current management approach is strict avoidance of the food. This is clearly an imperfect option as it can be difficult to avoid completely peanut and tree nuts and accidental exposures are not uncommon. Only about 20% of those with peanut allergy, and <10% of those with tree nut allergy, are reported to acquire tolerance. Additionally, peanut allergy can recur, with one study finding a recurrence rate of 8%. Peanut and tree nuts are the foods most frequently associated with fatal episodes of anaphylaxis. This is of particular concern in adolescents and young adults, among whom life-threatening and fatal food allergy-related reactions are most common.

Peanut allergy

Peanut allergy has become a major health concern worldwide, especially in developed countries. However, the reasons for this increasing prevalence over the past several decades are not well understood. Because of the potentially severe health consequences of peanut allergy, those suspected of having had an allergic reaction to peanuts deserve a thorough evaluation. All patients with peanut allergy should be given an emergency management plan, as well as epinephrine and antihistamines to have on hand at all times. Patients and families should be taught to recognise early allergic reactions to peanuts and how to implement appropriate peanut-avoidance strategies. It is imperative that severe, or potentially severe, reactions be treated promptly with intramuscular epinephrine and oral antihistamines. Patients who have had such a reaction should be kept under observation in a hospital emergency department or equivalent for up to 4 h because of the possible development of the late-phase allergic response. This Seminar looks at the changing epidemiology of this allergy--and theories as to the rise in prevalence, diagnosis, and management of the allergy, and potential new treatments and prevention strategies under development.

Self-injectable epinephrine for allergic emergencies

Anaphylaxis is a severe, life-threatening systemic reaction that can affect all ages. Epinephrine is frequently cited as the first-line and single most important agent in the treatment of severe allergic emergencies. Prompt administration of self-injectable epinephrine by patients and caretakers remains a key component in effective out-of-hospital management. This article will review the technique for self-injectable epinephrine administration in allergic emergencies, including discussion of the available dosages and formulations, indications, as well as other issues related to its use.

Severe allergic reaction: management of anaphylaxis in hospital

Anaphylaxis is an acute, severe, hypersensitivity reaction that can lead to asphyxia, cardiovascular collapse and cardiac arrest. This reaction is sudden, severe, and involves the whole body. Common causes include foods such as nuts, shellfish, dairy products and eggs. Non-food causes include bee/wasp stings, latex and drugs, e.g. penicillin. Common clinical features include urticaria, angioedema, respiratory distress and shock. Summoning expert help, reclining the patient flat, administering high concentration oxygen, and administering intramuscular adrenaline are key aspects of the nursing management of anaphylaxis in hospital. The aim of this article is to understand the management of anaphylaxis in hospital, with particular reference to national consensus guidelines.

Erratic absorption of intramuscular antimicrobial delivery in infants and children

In the absence of intravenous or enteral access, an intramuscular (IM) injection of medications is a viable alternative. Vaccines, antibiotics and analgesics are commonly administered by this route in pediatric medicine to enhance adherence to regimens. Although it is expected that the entire dose be administered by the IM route, the absorption (rate and extent) of the medication from the muscle tissue into systemic circulation can be erratic and depends on the drug's physicochemical factors and patient-specific factors. Despite the variability in absorption, administration of medications by the IM route may be considered when medications do not need to attain maximal concentrations rapidly. IM injections are generally well-tolerated, but potential injury to the injected muscle and the proximal nerves should be recognized.

The management of anaphylaxis in childhood: position paper of the European academy of allergology and clinical immunology

Anaphylaxis is a growing paediatric clinical emergency that is difficult to diagnose because a consensus definition was lacking until recently. Many European countries have no specific guidelines for anaphylaxis. This position paper prepared by the EAACI Taskforce on Anaphylaxis in Children aims to provide practical guidelines for managing anaphylaxis in childhood based on the limited evidence available. Intramuscular adrenaline is the acknowledged first-line therapy for anaphylaxis, in hospital and in the community, and should be given as soon as the condition is recognized. Additional therapies such as volume support, nebulized bronchodilators, antihistamines or corticosteroids are supplementary to adrenaline. There are no absolute contraindications to administering adrenaline in children. Allergy assessment is mandatory in all children with a history of anaphylaxis because it is essential to identify and avoid the allergen to prevent its recurrence. A tailored anaphylaxis management plan is needed, based on an individual risk assessment, which is influenced by the child's previous allergic reactions, other medical conditions and social circumstances. Collaborative partnerships should be established, involving school staff, healthcare professionals and patients' organizations. Absolute indications for prescribing self-injectable adrenaline are prior cardiorespiratory reactions, exercise-induced anaphylaxis, idiopathic anaphylaxis and persistent asthma with food allergy. Relative indications include peanut or tree nut allergy, reactions to small quantities of a given food, food allergy in teenagers and living far away from a medical facility. The creation of national and European databases is expected to generate better-quality data and help develop a stepwise approach for a better management of paediatric anaphylaxis.

Anaphylaxis: office management and prevention

Anaphylaxis, an acute and potentially lethal multisystem allergic reaction, is almost unavoidable in medical practice. Health care professionals must be able to recognize the signs of anaphylaxis, treat an episode promptly and appropriately, and be able to provide preventive recommendations. Epinephrine, which should be administered immediately, is the drug of choice for acute anaphylaxis.

Anaphylactic reactions during immunotherapy

Subcutaneous immunotherapy (IT) with aeroallergen extracts is venerable treatment modality. The major risk associated with IT with commercial aeroallergen extracts is the uncommon occurrence of severe near-fatal or fatal anaphylaxis after injections. The objectives of this article are to review the reported incidences of severe anaphylaxis (near-fatal reactions and fatal reactions), define factors contributing to these events, and identify preventive measures that are likely to reduce or eliminate future fatal and near-fatal anaphylactic events. As with any treatment, anticipated benefits attributed to IT must be weighed against its potential risks.

Anaphylaxis: evidence-based long-term risk reduction in the community

Anaphylaxis occurs frequently in the community, and it can be fatal in community settings. Risk assessment and risk reduction should ideally be coordinated by an allergy/immunology specialist and focus on: (1) prevention of subsequent anaphylaxis episodes, (2) emergency preparedness, and (3) anaphylaxis education. Preventive strategies should include trigger avoidance, specific preventive measures, and optimal management of comorbidities. Despite best efforts to avoid anaphylaxis triggers they can be encountered inadvertently, and anaphylaxis episodes can and do recur. Risk reduction therefore also focuses on emergency preparedness: carrying self-injectable epinephrine, having a personalized Anaphylaxis Emergency Action Plan, and wearing accurate medical identification. Anaphylaxis education should involve not only at-risk individuals and their families, but also health care professionals and the general public.

Navigating the updated anaphylaxis parameters

: Anaphylaxis, an acute and potentially lethal multi-system clinical syndrome resulting from the sudden, systemic degranulation of mast cells and basophils, occurs in a variety of clinical scenarios and is almost unavoidable inmedical practice. Healthcare professionalsmust be able to recognize its features, treat an episode promptly and appropriately, and be able to provide recommendations to prevent future episodes. Epinephrine, administered immediately, is the drug of choice for acute anaphylaxis. The discussion provides an overview of one set of evidence-based and consensus parameters for the diagnosis and management of anaphylaxis.

Prise en charge d'une réaction anaphylactique en extrahospitalier et aux urgences: revue de la littérature

Care and therapy of patients experiencing an anaphylactic reaction should be known by the physicians working in the emergency medical unit or in pre-hospital care. The epidemiology of these reactions varies according to the countries. The main aetiologies are due to food, hymenoptera or drugs. The clinical scale proposed by Ring and Messmer aims to classify the reactions in 4 grades according to their severity and is useful to stratify therapy. According to the grade of the reaction, the drug of choice for the treatment of anaphylaxis is epinephrine associated to vascular expansion. Anaphylaxis during pregnancy is described. Patients who experienced an immediate hypersensitivity reaction should undergo an allergological investigation to prove the immune mechanism and to identify the culprit allergen. Reporting to the Drug Safety Monitoring Authorities when a drug is implicated should not be forgotten.

Self-injectable epinephrine for first-aid management of anaphylaxis

Anaphylaxis is a severe, potentially fatal systemic allergic reaction that is rapid in onset and may cause death. Epinephrine is the primary medical therapy, and it must be administered promptly. This clinical report focuses on practical issues concerning the administration of self-injectable epinephrine for first-aid treatment of anaphylaxis in the community. The recommended epinephrine dose for anaphylaxis in children, based primarily on anecdotal evidence, is 0.01 mg/kg, up to 0.30 mg. Intramuscular injection of epinephrine into the lateral thigh (vastus lateralis) is the preferred route for therapy in first-aid treatment. Epinephrine autoinjectors are currently available in only 2 fixed doses: 0.15 and 0.30 mg. On the basis of current, albeit limited, data, it seems reasonable to recommend autoinjectors with 0.15 mg of epinephrine for otherwise healthy young children who weigh 10 to 25 kg (22-55 lb) and autoinjectors with 0.30 mg of epinephrine for those who weigh approximately 25 kg (55 lb) or more; however, specific clinical circumstances must be considered in these decisions. This report also describes several quandaries in regard to management, including the selection of dose, indications for prescribing an autoinjector, and decisions regarding when to inject epinephrine. Effective care for individuals at risk of anaphylaxis requires a comprehensive management approach involving families, allergic children, schools, camps, and other youth organizations. Risk reduction entails confirmation of the trigger, discussion of avoidance of the relevant allergen, a written individualized emergency anaphylaxis action plan, and education of supervising adults with regard to recognition and treatment of anaphylaxis.

A model protocol for emergency medical services management of asthma exacerbations

Emergency medical services (EMS) is an important part of the continuum of asthma management. The magnitude of the EMS responsibility is very large, with millions of patients with asthma treated each year by EMS personnel. In response to inconsistencies between the 1997 National Asthma Education and Prevention Program asthma guidelines and a variety of existing EMS protocols on the management of asthma exacerbations, the Centers for Disease Control and Prevention convened a workgroup in 2004 to discuss the various opportunities and challenges ahead. At the meeting, and over the ensuing year, the workgroup created a model protocol that was derived from the National Asthma Education and Prevention Program guidelines. The model protocol is available in both text and algorithm format and offers guidance for EMS systems to develop and implement treatment protocols in their local areas. The workgroup recommendations emphasize flexibility, simplicity, and low-risk practices. By integrating these recommendations into existing protocols, we believe that EMS systems could improve prehospital care for patients with asthma. Demonstration projects are needed to carefully examine the implementation process and the actual impact of the model protocol on various outcomes. The workgroup also encourages more research on EMS management of asthma exacerbations. In the meantime, improved collaboration between EMS and national asthma organizations is an immediate priority and will continue to advance future discussions on how to improve asthma management in the prehospital setting. The workgroup hopes that state and local EMS systems will see the value of the model protocol and encourage its use.

Anaphylaxis: clinical concepts and research priorities

Anaphylaxis is a severe immediate-type hypersensitivity reaction characterized by life-threatening upper airway obstruction bronchospasm and hypotension. Although many episodes are easy to diagnose by the combination of characteristic skin features with other organ effects, this is not always the case and a workable clinical definition of anaphylaxis and useful biomarkers of the condition have been elusive. A recently proposed consensus definition is ready for prospective validation. The cornerstones of management are the supine position, adrenaline and volume resuscitation. An intramuscular dose of adrenaline is generally recommended to initiate treatment. If additional adrenaline is required, then a controlled intravenous infusion might be more efficacious and safer than intravenous bolus administration. Additional bronchodilator treatment with continuous salbutamol and corticosteroids are used for severe and/or refractory bronchospasm. Aggressive volume resuscitation, selective vasopressors, atropine (for bradycardia), inotropes that bypass the beta-adrenoreceptor and bedside echocardiographic assessment should be considered for hypotension that is refractory to treatment. Management guidelines continue to be opinion- and consensus-based, with retrospective studies accounting for the vast majority of clinical research papers on the topic. The clinical spectrum of anaphylaxis including major disease subgroups requires clarification, and validated scoring systems and outcome measures are needed to enable good-quality prospective observational studies and randomized controlled trials. A systematic approach with multicentre collaboration is required to improve our understanding and management of this disease.

Food allergies: prevalence, molecular characterization, and treatment/prevention strategies

A significant proportion of the population is either affected by or concerned about food allergy. Our knowledge about food allergens and how they stimulate the immune system has increased dramatically over the past decade. However, reasons for the increased prevalence of food allergy are not clear. The diagnosis of food allergy requires that the patient and caregivers examine all foods for the presence of potential allergens in order to prevent inadvertent ingestion and further reactions. Fortunately, many children develop tolerance to allergenic foods after a period of dietary elimination. Various immunotherapy approaches are under investigation to alleviate or prevent food-induced reactions in those who have persistent food allergies.

Dietary management of food allergy

Food allergy is a modifiable disease, and at present its only form of management is dietary elimination of the offending food or foods. Success depends on the modification of four sources of food-related risk: underestimation of the food allergy problem; ignorance of cross-reacting allergens in other foods; unsupportive or uninformed measures from the family or school environments; and inadequate social recognition that food allergy is a growing public health problem. Ultimately, the empowerment of children with allergies through education, allergist and dietician guidance, and patient association feedback can minimize the morbidity of food allergy and enhance the quality of life of both the child and the family. From a research perspective, studies on the longterm efficacy of the dietary exclusion of specific food allergens are needed. The role of the pediatrician is central in this regard and would be complemented by advice from a nutritionist.

Oculogyric Dystonic Reaction to Escitalopram with Features of Anaphylaxis Including Response to Epinephrine

Dystonia-associated features of anaphylaxis, including tongue swelling, and chest and throat tightness, have been rarely reported with selective serotonin reuptake inhibitor (SSRI) use. The patient is a 44-year-old woman who presented with palpitations, diaphoresis, dyspnea, swelling of the lips and tongue, and fixed upward deviation of her right eye following inadvertent ingestion of 20 mg of escitalopram in addition to her usual 10-mg dose. She reported transient resolution of all symptoms after autoinjector aqueous epinephrine administration (0.3 mg), with recurrence of symptoms after 35 min. The patient presented with one prior episode of anaphylactic symptoms and dystonia. She also reported one episode with purely anaphylactic features of swelling of lips and tongue, difficulty breathing and syncope. This case represents a unique dose-dependent episode of escitalopram-associated oculogyric dystonia with anaphylactic features. The transient resolution of the associated features of dystonia with intramuscular epinephrine administration is unique and suggests a common pathophysiology of the dystonic and anaphylactic symptoms.

Second Symposium on the Definition and Management of Anaphylaxis: Summary Report—Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network Symposium

There is no universal agreement on the definition of anaphylaxis or the criteria for diagnosis. In July 2005, the National Institute of Allergy and Infectious Disease and Food Allergy and Anaphylaxis Network convened a second meeting on anaphylaxis, which included representatives from 16 different organizations or government bodies, including representatives from North America, Europe, and Australia, to continue working toward a universally accepted definition of anaphylaxis, establish clinical criteria that would accurately identify cases of anaphylaxis with high precision, further review the evidence on the most appropriate management of anaphylaxis, and outline the research needs in this area.

Second symposium on the definition and management of anaphylaxis: summary report--Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium

There is no universal agreement on the definition of anaphylaxis or the criteria for diagnosis. In July 2005, the National Institute of Allergy and Infectious Disease and Food Allergy and Anaphylaxis Network convened a second meeting on anaphylaxis, which included representatives from 16 different organizations or government bodies, including representatives from North America, Europe, and Australia, to continue working toward a universally accepted definition of anaphylaxis, establish clinical criteria that would accurately identify cases of anaphylaxis with high precision, further review the evidence on the most appropriate management of anaphylaxis, and outline the research needs in this area.

Sublingual epinephrine tablets versus intramuscular injection of epinephrine: Dose equivalence for potential treatment of anaphylaxis

BACKGROUND

Epinephrine autoinjectors are underused in the emergency treatment of anaphylaxis in the community, perhaps in part because of fear of needles.

OBJECTIVES

To determine the sublingual epinephrine dose from a novel fast-disintegrating tablet required to achieve epinephrine plasma concentrations (EPPCs) similar to those obtained after epinephrine 0.3 mg intramuscular injection.

METHODS

In a prospective 5-way crossover study, sublingual tablets containing epinephrine 0, 10, 20, and 40 mg, and epinephrine 0.3 mg intramuscular in the thigh (EpiPen) were compared in a validated rabbit model. Blood samples were collected before dosing and 5, 10, 15, 20, 30, 40, 60, 90, 120, 150, and 180 minutes afterward. EPPCs were measured by using high-performance liquid chromatography-electrochemical detection. Pharmacokinetic parameters were calculated by using WinNonlin.

RESULTS

The area under the curve (AUC), maximum concentration (C(max)), and time at which C(max) was achieved (T(max)) did not differ significantly (P > .05) after epinephrine 40 mg (AUC = 1861 +/- 537 ng/mL/min, C(max) = 31.0 +/- 13.1 ng/mL, and T(max) = 9 +/- 2 minutes) and epinephrine 0.3 mg intramuscular (AUC = 2431 +/- 386 ng/mL/min, C(max) = 50.3 +/- 17.1 ng/mL, and T(max) = 21 +/- 5 minutes). The AUC after tablets containing epinephrine 0 mg (AUC = 472 +/- 126 ng/mL/min), epinephrine 10 mg (AUC = 335 +/- 152 ng/mL/min), and epinephrine 20 mg (AUC = 801 +/- 160 ng/mL/min) did not differ significantly from each other, but were significantly lower (P < .05) than the AUC after epinephrine 0.3 mg intramuscularly.

CONCLUSION

Sublingual administration of epinephrine 40 mg from this tablet formulation resulted in EPPCs similar to those obtained after epinephrine 0.3 mg intramuscular injection in the thigh.

CLINICAL IMPLICATIONS

For treatment of anaphylaxis in the community, self-injectable epinephrine is underused. This novel, fast-disintegrating epinephrine tablet formulation for sublingual administration is a feasible alternative that warrants further development.

Immunotherapy: first do no harm

Immunotherapy continues to be a treatment modality that is used most exclusively by allergists. The acceptance of immunotherapy for treating children with allergic rhinitis or asthma has been limited by the lack of adequate numbers of pediatric double-blind, placebo-controlled trials of specific allergen immunotherapy; use of venom immunotherapy is more clearly supported by current data. Children represent a unique group of patients where allergic disease may not only be treated using immunotherapy resulting in reduction of symptoms, signs, and complications of disease, but may also hold the best potential for the evasive goal of prevention of the development of future allergic disease.

Adequacy of the epinephrine autoinjector needle length in delivering epinephrine to the intramuscular tissues

BACKGROUND

Epinephrine injected by an autoinjector in the anterolateral aspect of the thigh is the standard of care in the emergency self-treatment of anaphylaxis. In the United States, the autoinjector EpiPen is widely used for the self-treatment of anaphylaxis.

OBJECTIVE

To investigate whether EpiPen autoinjector, with a needle length of 1.43 cm, is sufficient for intramuscular delivery of epinephrine in men and women.

METHODS

The distance from skin to muscle in the anterolateral aspect of the thigh was measured in 50 men and 50 women who had undergone computed tomography of the thighs for other medical reasons. For each individual, body mass index (BMI; a measure of weight in kilograms divided by the square of height in meters) was also calculated, and the individuals were classified as underweight (BMI, < 18.5), normal (BMI, 18.5-24.9), overweight (BMI, 25.0-29.9), and obese (BMI, > or = 30.0) using standard definition.

RESULTS

In the study participants the mean +/- SD distance from skin to muscle was 0.66 +/- 0.47 cm for men and 1.48 +/- 0.72 cm for women (P < .001). One man (obese at a BMI of 42.2) and 21 women (11 obese with a mean BMI of 35.2, 6 overweight with a mean BMI of 30.1, and 4 normal with a mean BMI of 24.5) had a greater distance from skin to muscle than the EpiPen needle length of 1.43 cm.

CONCLUSION

The distance from skin to muscle for the anterolateral aspect of the thigh is higher in women compared with men. This difference suggests that EpiPen may not deliver epinephrine to the intramuscular tissue in many women.

Cardiovascular responses in patients with acute allergic reactions treated with parenteral epinephrine

The present study describes the cardiovascular responses to epinephrine (Epi) given into the arm, in adult patients with acute allergic reactions, and the differential responses to subcutaneous (SC) and intramuscular (IM) administration. Sixty-three adult patients were treated with Epi administered SC or IM after H1 and H2 receptor blockade. Heart rate and blood pressure (BP) were then measured for 20 minutes. Changes in heart rate and BP variables were analyzed. Pulse pressure and systolic BP showed increases with time. Diastolic BP also showed a modestly decreasing values over time. Heart rates did not change. Time-related changes between IM and SC Epi treatment were not observed. Sex influenced timed BP values and a significant sex by time effect was observed. In subset analysis, only male patients showed an overall time effect for BP variables, especially pulse pressure. In conclusion, adults with acute allergic syndromes treated with arm-injected Epi show a modest but definite increase in pulse pressure and systolic BP. This pattern is observed more in males. Heart rate and blood pressure differences between IM and SC arm-injected Epi treatments do not appear to be significant.

Constant infusion of epinephrine, but not bolus treatment, improves haemodynamic recovery in anaphylactic shock in dogs

OBJECTIVE

Epinephrine (Epi) is the treatment of choice for reversing cardiovascular collapse in anaphylactic shock (AS). In this condition, most treatment guidelines have been anecdotally derived and no randomized clinical trials have been conducted. In the present study, we examined the time course of haemodynamic recovery in a canine model of AS when Epi was administered at the initiation of allergen challenge before fully developed shock had occurred.

METHODS

Randomized, controlled, crossover studies were performed approximately 3-5 weeks apart in ragweed-sensitized dogs while the animals were ventilated and anaesthetized. Epi was administered by bolus intravenous (i.v.), subcutaneous (s.c.), intramuscular (i.m.) routes and by continuous i.v. infusion (CI). The findings obtained in the Epi treatment (T) studies were compared with those found in a no treatment (NT) study. In the bolus studies, Epi was administered at 0.01 mg/kg, while in the CI study, the dose of Epi was titrated to maintain mean arterial pressure (MAP) at 70% of preshock levels. MAP, cardiac output (CO), stroke volume (SV), and pulmonary wedge pressure (Pwp) were determined over a 3 h period.

RESULTS

In the CI study, haemodynamics (CO, MAP, and SV) were significantly higher than those measured in the NT study and the bolus studies over approximately the first hour of the study. In the CI study, the amount of Epi infused was significantly less than in the bolus studies.

CONCLUSION

When administered at the initiation of allergen challenge, bolus treatment of Epi by i.m., i.v., or s.c. routes caused limited haemodynamic improvement in AS. In contrast, constant infusion of Epi at a lower total dose produced significant haemodynamic improvement. Within the limits of this anaesthetized canine model, the results suggest that CI should be the preferred route in the treatment of AS when this treatment option is available.

Clinical evaluation and management of drug hypersensitivity

Adverse drug reactions are a major health problem in the inpatient and outpatient clinical setting. Although all of the immune mechanisms of drug reactions are not well characterized, a detailed medication history, knowledge of the signs and symptoms associated with known immune mechanisms, and knowledge of the types of medications typically associated with distinct immune reactions are helpful in implicating the causative drug. Standardized testing for drug reactions is limited, especially for non-IgE-mediated reactions. Management consists of stopping the offending drug, treating the acute reaction, and making a determination concerning future use of the drug.

Adrenaline in the treatment of anaphylaxis: what is the evidence?

Adrenaline (epinephrine) is the recommended first line treatment for patients with anaphylaxis. This review discusses the safety and efficacy of adrenaline in the treatment of anaphylaxis in the light of currently available evidence. A pragmatic approach to use of adrenaline auto-injectors is suggested.

What Are the Acute Cardiovascular Effects of Subcutaneous and Topical Epinephrine for Hemostasis During Burn Surgery?

Although subcutaneous and topical epinephrine are widely used for hemostasis during burn surgery, the acute systemic cardiovascular effects of the epinephrine are neither well documented nor completely understood. The purpose of this work was to prospectively study the acute cardiovascular responses to epinephrine (epi) administered subcutaneously and topically during burn surgery. Consecutive patients who received subcutaneous and topical epi during burn surgery were monitored prior to the administration of epi, at 2-minute intervals during subcutaneous epi infiltration, and then after epi infiltration (during which time, topical epi was applied). This period of monitoring lasted up to 20 minutes and was referred to as an epinephrine event (EE). A total of 100 EEs from 38 operations in 24 patients (mean +/- SD: age 43 +/- 16 years, mean % TBSA burn 23 +/- 17%) were studied. The mean dose of subcutaneous epi was 30 +/- 30 microg/kg. Although all patients received topical epi, it was impossible to document the topical dose. There was no significant increase in heart rate from baseline, and no arrhythmias occurred. Mean arterial pressure (MAP) did acutely increase significantly by 17.0 +/- 14.1% from baseline (P =.009) and increased more than 10% from baseline in 64/100 EEs. However, the increase in MAP was independent of the dose of epi (r =.053). The increase in MAP was not clinically significant, did not require intervention, and did not appear to be related to the type of wound that received epi (donor site vs burn wound), or the depth of anesthesia, analgesia, or sedation. On the basis of these findings, the use of subcutaneous and topical epi appears to be safe and produces minimal acute cardiovascular effects.

Use of epinephrine in the treatment of anaphylaxis

PURPOSE OF REVIEW

This paper is intended to review recent literature that impacts the use of epinephrine in the therapy of anaphylaxis.

RECENT FINDINGS

The most important recent finding regarding the administration of epinephrine is that the intramuscular route of administration is the route of choice for the treatment of anaphylaxis, and the lateral aspect of the thigh is the site of choice. In addition, recent research emphasizes the fact that epinephrine is grossly underused in the management of anaphylaxis, which accentuates the need for further education of both physician and patient in this regard.

SUMMARY

Several major themes have emerged from this review of the recent literature. The finding that the intramuscular route of administration for epinephrine is superior has now been recognized by the guidelines, and because the site of choice has been found to be the lateral aspect of the thigh, the needle used for injection must be long enough to penetrate the vastus lateralis muscle. The reasons for the underutilization of epinephrine in the treatment of anaphylaxis are also discussed. Other important findings include the fact that outdated EpiPens can usually be administered safely, and alternative routes of administration, which may be more acceptable to patients, may be on the horizon as a result of preliminary studies assessing the administration of sublingual epinephrine by wafer. Finally, it is now understood that epinephrine prescription data may be one of our best tools to study the epidemiology and incidence of anaphylactic episodes.

Advances in anaphylaxis and hypersensitivity reactions to foods, drugs, and insect venom

This review highlights some of the research advances in anaphylaxis and hypersensitivity reactions to foods, drugs, and insect venom that were reported primarily in this Journal from 2001 to 2002. Among the topics highlighted: Epinephrine injected intramuscularly into the thigh provides the most efficient absorption profile for adults and children; determination of serum IgE antibody-specific food allergen concentrations and atopy patch tests with foods show promise for enhanced diagnostic accuracy; numerous food allergens are now characterized on the molecular level, allowing for improved diagnostic and treatment modalities; the complex immunologic mechanisms underlying drug hypersensitivity reactions are being elucidated; venom immunotherapy improves quality of life for sufferers, and increased venom immunotherapy doses are useful in recalcitrant cases.

Immediate allergic reactions to beta-lactams: diagnosis and therapy

Beta-lactams are the antibiotics which most frequently provoke adverse reactions mediated by specific immunological mechanisms. These reactions, classifiable as immediate or non-immediate, can be produced by the four classes of beta-lactams (penicillins, cephalosporins, carbapenems and monobactams) currently available, which share a common beta-lactam ring structure. Immediate reactions occur within the first hour after drug administration and are characterized by urticaria, angioedema, rhinitis, bronchospasm, and anaphylactic shock. Immediate reading skin tests are the quickest and most reliable method for demonstrating the presence of beta-lactam specific IgE antibodies. It is crucial to use in diagnosis the suspected beta-lactams themselves, particularly cephalosporins, in addition to penicillin determinants. Serum specific IgE assays can be used as complementary tests. Negative test results should be interpreted in light of the time elapsed from the last exposure to the responsible beta-lactam. In fact, both in vivo and in vitro test sensitivity is known to decrease over time. In some diagnostic work-ups, patients with a positive history and negative skin and in vitro tests with classic reagents undergo a controlled administration of the suspected beta-lactam. The management of immediate allergic reactions should take into consideration their severity and type. Adrenaline is the drug of choice in the treatment of anaphylactic shock. In addition to adrenaline, corticosteroids and antihistamines should be administered. Histamine H(1) receptor antagonists are the mainstay of the treatment of immediate allergic reactions such as urticaria, rhinitis and conjunctivitis.

The role of epinephrine in the treatment of anaphylaxis

Epinephrine is the cornerstone of anaphylaxis management. Its administration should be immediate upon evidence of the occurrence of anaphylaxis. Delays in administration may be fatal. The most appropriate administration is 0.3 to 0.5 mL of 1:1000 dilution intramuscularly for adults and 0.01 mg/kg for children, given in the lateral thigh. Patients with known anaphylactic reactivity should be prescribed an epinephrine auto-injector to be carried at all times for treatment of potential recurrences. Education of the patient or parent regarding the proper use of this tool is paramount.