Perioperative anaphylaxis: pathophysiology, clinical presentation and management

Abstract

By reading this article you should be able to: Describe trends in the incidence and agents that cause perioperative anaphylaxis. Explain the underlying pathophysiology. Distinguish the different patterns of clinical presentation and apply the Ring and Messmer severity grading scale. Implement appropriate management for patients with anaphylaxis. Perioperative anaphylaxis is a life-threatening immediate hypersensitivity condition that is usually immunoglobulin E (IgE)-mediated. It occurs rarely, but may lead to morbidity or mortality. The aims of this article are to: i) review the current nomenclature, ii) discuss the key epidemiological points, iii) highlight the key aspects of the underlying pathophysiology, iv) discuss the acute management and therapeutic approach to cardiovascular collapse refractory to adrenaline (epinephrine) and v) discuss briefly the identification of the culprit drug. This article focuses on perioperative anaphylaxis (Grades III and IV) and not the less severe clinical presentations (Grades I and II). We do not discuss perioperative anaphylaxis in children, which appears to be rare. 1 Anaphylaxis in obstetric anaesthesia has been detailed elsewhere.

Severe bronchoconstriction as part of a suspected anaphylactic reaction in a dog following administration of gadobutrol

“…Anaphylactic reactions are acute, potentially life-threatening systemic reactions to an inciting substance 1–4. Its pathophysiology and clinical presentation are complex and varied, and can make the diagnosis and identification of the inciting factor challenging in some circumstances 1.…”

“…Clinical presentation can be variable due to the many complex reactions occurring following an anaphylactic event and not all effects will be clinically detectable in every case. Cutaneous signs such as erythema, urticaria and pruritus are commonly reported in both people and dogs 1 2 4. Cutaneous signs may, however, be absent in the event of acute cardiovascular collapse 1 4.…”

“…Cutaneous signs such as erythema, urticaria and pruritus are commonly reported in both people and dogs 1 2 4. Cutaneous signs may, however, be absent in the event of acute cardiovascular collapse 1 4. Gastrointestinal signs such as nausea, vomiting, and haemorrhagic or non-haemorrhagic diarrhoea are common 1 3.…”

“…Progression of anaphylactic reactions is usually rapid, with clinical signs seen within 5–30 minutes of antigen exposure and with progression of subsequent clinical signs over minutes or hours 1 2. Diagnostic criteria have been defined in people to aid detection and classification of severity as case presentation is variable 2 4…”

“…Adrenaline is considered an essential medication in the treatment of anaphylaxis 1–4. In people, intramuscular administration at initial onset of signs, rather than on admittance to the emergency department, significantly reduces the likelihood of hospitalisation 2 4. Agonism of α1 adrenoreceptors causes peripheral vasoconstriction, counteracting vasodilatory and redistributive hypotension and shock, and relieves oedema of the upper airway.…”