Post-arrest Management

The preferred disposal for your patient with recovery of spontaneous circulation from anaphylaxis-induced cardiac arrest is intensive care.

In the meantime:

• Start a titrated adrenaline infusion — follow local policy.
• Insert an arterial line to guide therapy
• Give 200 mg IV hydrocortisone and 10 mg chlorpheniramine (slowly) if these have not already been administered
• Measure the serum tryptase level (in a standard U&Es bottle) labelling the time carefully. Arrange repeat measurement 1-2 hours later, in order to help confirm true anaphylaxis. Ideally a sample after 24 hours or in convalescence (eg at follow up clinic) should be taken as some people have elevated baseline levels [1]
• Consider targeted temperature management as per local guidelines in patients not regaining consciousness
• Document the need for in-hospital teams to arrange the following for your patient — Medic alert bracelet, auto-injector (and education in its use and administration) and referral to an immunologist

• Remember that a biphasic reaction can recur many hours later
• In cases of drug-induced anaphylaxis, report the incident to the Medicines and Healthcare products Regulatory Agency (MHRA) using the yellow card scheme (www.mhra.gov.uk). The BNF includes copies of the yellow card at the back of each edition

Learning bite

Measure the serum tryptase level post-resuscitation and 1-2 hours later to help confirm true anaphylaxis.

Survivors of peri-arrest anaphylaxis require a Medic alert bracelet, adrenaline auto-injector (provision and education) and referral to an immunologist.