A hypersensitivity screening clinic following untoward reactions to anaesthesia.

Anaphylactoid or anaphylactic reactions to drugs used during general anaesthesia are potentially life threatening. It is important that they be differentiated from other types of cardio-respiratory collapse. At present a detailed history of the time sequence of events in relation to drug administration is of a greatest importance. Retrospective skin testing may then indicate which agent was involved, although false positives and false negatives may occur. Forty-nine patients who presented with a history of collapse during anaesthesia over a five year period were skin tested. Positive results were obtained in 22, ten gave inconclusive test results but a strongly suggestive history. The remainder were considered to have other causes for their clinical presentation. The incidence of severe reactions confirmed by history and by skin testing in this community is approximately 1:4000.