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.
Concern |
Comment |
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 |
extubation |
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 |
where:
• Off-pump cardiac surgery is preferred since use of a cardiac pump can activate complement.
Specialty: Anesthesiology, Pedatrics, Genetics