COMPLEMENT ACTIVATION DURING MAJOR SURGERY - THE EFFECT OF EXTRACORPOREAL CIRCUITS AND HIGH-DOSE APROTININ

Objective: To assess the in vivo contribution to complement activation of an extracorporeal circuit and the use of high-dose aprotinin durin g major surgery Design: Sequential samples were obtained from 8 patien ts undergoing thoracic surgery, 20 patients undergoing orthotopic live r transplantation (OLT) using venovenous bypass, and 19 patients under going cardiac surgery using cardiopulmonary bypass (CPB). Intervention :The latter two groups were part of a randomized controlled trial of h igh-dose aprotinin. Measurements: Total complement activation was meas ured with the hemolytic complement activity and the C3 activation-spec ific marker, C3d antigen. Main Results: Complement activation did not occur during thoracic surgery During OLT, C3d antigen levels, expresse d as mean +/- standard deviation (SD), were elevated from baseline at skin closure (8.6 +/- 2.5 v 13.0 +/- 5.2 mg/L; p = 0.0082). During car diac surgery, C3d antigen levels increased 10 minutes after the start of CPB (pre-CPB, 8.0 +/- 1.9 v 14.2 +/- 3.1 mg/L; p = 0.0001) and rema ined at greater than baseline values postoperatively (8.0 +/- 1.9 v 11 .8 +/- 2.3 mg/L; p = 0.002). There was no difference in complement act ivation in those receiving high-dose aprotinin during OLT or cardiac s urgery. Complement activation during cardiac surgery using extracorpor eal circulation occurred to a greater extent than during OLT and thora cic surgery. Complement activation during cardiac surgery or OLT was n ot attenuated by the use of high-dose aprotinin. Copyright (C) 1998 by W.B. Saunders Company.