Hereditary angioedema (HAE) is associated with a hereditary deficiency in C1 esterase inhibitor. Deficiency in C1 esterase inhibitor is associated with uncontrolled activation of complement with generation of C2 kinin and bradykinin. These substances can result in peribronchial edema and angioedema, which can block the airway.




knowledge of HAE in advance

allows for planning and prevention while avoiding emergencies in the OR

maintaining an adequate level of C1 esterase inhibitor during and after the procedure

C1 esterase inhibitor concentrate preferred. Fresh frozen plasma (FFP) can be used but this can also increase complement levels.

prophylaxis to maintain C1 esterase inhibitor levels

therapy with synthetic androgens (danazol, stanozolol) prior to surgery

prophylaxis with antifibrinolytic agents

therapy inhibits activation of plasminogen and C1

airway protection

intubation prior to surgery; therapy with epinephrine, antihistamines and corticosteroids are often ineffective


when stable, with emergency reintubation readily available

activation of complement by procedure

select procedure that is least traumatic and which is least likely to activate complement

protamine reversal of heparin therapy

minimize doses of both heparin and protamine since heparin-protamine complexes may activate complement

fluid administration

excessive fluid administration may dilute existing levels of C1 esterase inhibitor



• Off-pump cardiac surgery is preferred since use of a cardiac pump can activate complement.


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