Plasma aprotinin concentrations during cardiac surgery: Full-versus half-dose regimens

Aprotinin is an effective but expensive drug used during cardiac surgery to reduce blood loss and transfusion requirements. Currently, aprotinin is ad ministered to adults according to a fixed protocol regardless of the patien t's weight. The purpose of this study was to determine aprotinin levels in patients receiving full- and half-dose aprotinin regimens by a simple funct ional aprotinin assay and to design a more individualized aprotinin dosage regimen for cardiac surgical patients. The mean plasma aprotinin concentrat ion peaked 5 min after the initiation of cardiopulmonary bypass (full 401 /- 92 KIU/mL, half 226 +/- 56 KIU/mL). The mean plasma aprotinin concentrat ion after 60 min on cardiopulmonary bypass was less (full 236 +/- 81 KIU/mL , half 160 +/- 63 KIU/mL). There was large variation in the aprotinin conce ntration among patients. A statistically significant correlation was found between aprotinin concentration and patient weight (r(2) = 0.67, P < 0.05).