The effects of protamine on hemodynamics and oxygenation during cardiac surgery.

The cardiopulmonary effect of protamine for heparin reversal was investigated in 100 patients, undergoing cardiac surgery, using cardiopulmonary bypass (CPB) at Siriraj hospital. Protamine sulfate at approximately equal to the amount of heparin was intravenously administered over 3 minutes after termination of CPB, together with rapid blood transfusion to establish the optimal level of central venous pressure. Following protamine administration, the heart rate was measured at 5, 15 and 30 minutes, and was not significantly different from the preoperative and post CPB values. The blood pressure was significantly decreased in the initial post CPB (P less than 0.05) and remained unchanged 5 minutes following intravenous protamine, thereafter, significantly rose to preoperative values. The arterial oxygen tension post CPB revealed shunting effect, but showed no significant change following protamine administration. The occurrence of cardiopulmonary adverse effect was not demonstrated in this study.