The management of bleeding following surgery requiring hypothermic circulatory arrest

Hemostasis is a significant problem in aortic surgery requiring profoundly hypothermic techniques. Aprotinin, a serine protease inhibitor, reduces blood loss in high-risk coronary and valve surgery, but its use in profound hypothermia is controversial.

To evaluate the role of a modified protocol of aprotinin administration we have retrospectively reviewed our results in 73 procedures when hypothermic circulatory arrest was necessary. Thirty-seven (51%) were emergencies. Aprotinin was not administered until bypass had been recommenced after the period of circulatory arrest, and was then given as a bolus of 280 mg into the bypass machine followed by an intravenous infusion of 70 mg/hour.

In this series the 30-day mortality was 12.3% (9/73), and the in-hospital mortality 13.7% (10/73). Mortality in the elective group was 11.1% and 16.2% in the emergency group. The mean blood loss over the first 12 hours after surgery was 542 mL; the mean transfusion requirement during surgery and this 12 hour period was 3.6 units of blood. Six patients (8.2%) developed transient renal dysfunction which did not require intervention.

This data does not support the adverse effect of aprotinin upon early survival. Although early reports were of concern, the role of aprotinin as an adjunct to hemostasis requires further investigation.