[Haemochron--a simple method of monitoring heparin level during extracorporeal circulation].

Tow forms of heparin management during cardiopulmonary bypass were compared in order to analyze the role of the heparin level in relation to postoperative blood loss. The study was divided in three groups: In group I, the control group, 3 mg/kg body weight heparin was given as an initial dose and maintained at a dose of 1.0 mg/kg every 60 min during cardiopulmonary bypass; group II received the same initial dose, but additional doses were based upon the activated clotting time measured with a Haemochron; in group III, the Haemochron time was measured at 10-min intervals to establish a base value. In group II we found a significant decrease in postoperative blood loss as well as a decrease in the amount of heparin administered during cardiopulmonary bypass. In addition, fewer transfusions were required in the immediately postoperative period. In group III, wide variations in the activated clotting time curve were observed. No patients was underheparinized, but some had markedly prolonged Haemochron times.