Adrenaline in anaphylaxis: overtreatment in theory, undertreatment in reality.

‘Anaphylaxis is a clinical emergency, and all healthcare professionals should be familiar with its management’. Few health professionals would disagree with this opening sentence of new guidelines from the European Academy of Allergy and Clinical Immunology (EAACI), which aim to provide evidence-based recommendations for recognition, risk assessment, and management of patients who have experienced, are experiencing or are at risk of experiencing anaphylaxis. This care requires correct recognition of anaphylaxis, appropriate acute management and optimal long-term care: all important but distinct skills. Guidelines clarify what treatment should be given to whom and when. It would be hoped that, over time with codification of best practice, doctors’ abilities to accurately recognise and appropriately treat anaphylaxis would improve. However, Plumb and colleagues found, using brief written case scenarios, that junior doctors today seem to be no better at correctly identifying the clinical need for, and correct dose and route for administration of, adrenaline (epinephrine) than their predecessors a decade earlier. All doctors in this recent study recognised adrenaline as the appropriate treatment for a case scenario that clearly described anaphylaxis. However, many (21–82%) also selected adrenaline as treatment for scenarios describing situations in which adrenaline would not be appropriate—for example, inhalation of peanut or acute urticaria with no other system involvement. Little seems to have changed over time. A decade earlier, all junior doctors at the same hospital tested using the same scenarios selected adrenaline as treatment of choice for anaphylaxis, but some (10–56%) also indicated that they would use adrenaline for inappropriate scenarios. Similar results have been found elsewhere in the world. In our recent unpublished study from Auckland, all 22 postgraduate year 1 doctors tested using similar scenarios selected adrenaline to treat anaphylaxis, but 27–91% would also have used adrenaline inappropriately. A questionnaire study of doctors and nurses in a large Singapore hospital indicated good recognition of anaphylaxis but also a tendency to overdiagnosis. Anaphylaxis is typically rapid in onset, with involvement of more than one system: airway, breathing or circulatory and usually, but not always, skin or mucosal changes. In the Singapore study, 89% of emergency department doctors, the majority of whom had previously seen at least one case of anaphylaxis, chose adrenaline correctly for written scenarios describing symptoms that involved two systems. However, as in the UK study, there was a tendency to recommend adrenaline in patients with single organ (skin) involvement. It is crucial that the correct dose of adrenaline is delivered by the correct route. Incorrect use of intravenous adrenaline may endanger patients’ lives. While there was an improvement in both correct choice of dose and route of administration in the decade between the two UK studies, a significant number of doctors in all three studies selected the wrong dose and the wrong route. Given the evident lack of knowledge regarding the correct dose and route, easy access to a simple anaphylaxis algorithm, appropriate-strength (1:1000) adrenaline and the necessary syringes and needles should be provided on all resuscitation trolleys. Such an ‘anaphylaxis box’ was recently introduced in Auckland City Hospital and has been well received and considered very useful by resuscitation teams (boxes 1 and 2). A similar suggestion to place advance life support (ALS) anaphylaxis guidelines on resuscitation trolleys was made after another study of firstand second-year UK doctors in 2008 identified that even junior doctors who had completed ALS training had poor knowledge of adrenaline use and dose. It seems that, when tested in this way, doctors’ ability to discriminate between clinical descriptions of any complexity is imperfect and theoretically, at least, indicates intended overuse of adrenaline. However, this does not reflect what happens in practice. Delayed administration of adrenaline in patients with anaphylaxis has been shown to be a risk factor for poor outcome, 6 and retrospective audits show underuse of adrenaline to be common. Data from the UK register of fatal anaphylactic reactions shows non-administration of adrenaline happens in 39% of anaphylactic fatalities regardless of the precipitant. Although overdiagnosis of anaphylaxis has been found to contribute to harm to patients, this is rarer than omission of adrenaline. It is not clear why adrenaline is withheld in the face of anaphylaxis. Perhaps there is an element of panic, both in patients experiencing escalating life-threatening symptoms and in their attendant health professionals who do not often deal with such urgent ‘high-stakes’ clinical problems. Doctors may be unfamiliar with intramuscular administration of adrenaline. Possibly, there are some concerns about the potential Box 1 Recognise, treat, reassess