CERTAIN cardiac procedures might be more uniformly successful and free of complications if it were possible to maintain for a period of time a prolonged coagulation time of the blood within the heart and, at the same time, a normal clotting mechanism in the systemic circuit. The successful utilization of regional heparinization in conjunction with hemodialysis1,2 in extracorporeal liver perfusion studies3 provided a new element of hope and prompted the present study.
Healthy mongrel dogs, ranging in weight from 7.4 to 26.4 kg, were used. They were anesthetized by the intravenous administration of thiopental sodium (Pentothal). Following tracheal intubation, controlled respirations were maintained with a mechanical ventilator. Two groups of animals were studied.In the first group of 28 dogs, sodium heparin was administered through a No. 18 polyethylene catheter inserted into the left atrium through its appendage. Blood samples were drawn from 12-gauge Teflon catheters