Prostacyclin in aortocoronary bypass surgery: a double-blind, placebo-controlled study

In a double-blind, placebo-controlled trial of 40 patients requiring aortocoronary vene transplant surgery, prostacyclin (PGI2) was infused in a dose of 8 ng/kg/min throughout cardiopulmonary bypass. When compared with the placebo-group, the patients treated with PGI2 were found to have significantly higher platelet counts 60(2) and 90 minutes after onset of extra-corporeal circulation (EC). Although this platelet preservation by PGI2 was accompanied by less degranulation of alpha-granula, total antithrombin III (AT III) as well as active AT III and factor Xa inhibitory activity did show comparable results in both treatment groups. In the early phase of EC coagulation factors (fibrinogen, prothrombin and factor VII) exhibited a trend in favour of higher plasma levels in the PGI2-treated group. The same results were found for plasminogen. F VIII-related antigen and complement factors (C3, C4, C3 activator) did not show any difference between the two treatment groups. Bleeding times, blood loss and renal function also did not exhibit any significant differences between the two groups of patients. Except for one control (60 minutes after onset of EC) hemodynamic parameters were not significantly different between the two patient groups. Whether the trend in favour of a lower mortality in PGI2-treated patients can be confirmed, will be up to further studies with greater numbers of patients.