Avoidance of blood transfusion in coronary artery surgery: a trial of hydroxyethyl starch.

Banked blood transfusion, with its attendant hazards, may be avoided in certain instances. A search for an acceptable plasma substitute was made. A randomized prospective trial of hydroxyethyl starch (HES) versus plasma for postoperative volume replacement is described. Ninety patients undergoing operations for coronary artery disease were studied over a six-month period. Ten received banked blood in the immediate postoperative period and were excluded from the study. The remaining 80 were randomized into two groups. Group 1 received plasma, and Group 2 received HES. All patients initially had autologous blood transfusion, and in 7 patients this sufficed; these patients were excluded from the study except for regression analysis. Postoperative blood loss and urine output did not differ between groups, but Group 2 patients required significantly more volume replacement (p less than 0.02). In a total of 27 patients drawn from both groups, coagulation factors and colloid osmotic pressure were investigated. There were no significant differences in fibrinogen titer and prothrombin time between groups, but return to normal values was significantly delayed in the HES group (p less than 0.01). Activated clotting time and partial thromboplastin time were unaffected. Colloid osmotic pressure was significantly higher at one week in the HES group (p less than 0.001) and was correlated with the volume of HES given (r = 0.525; p less than 0.01). There were no untoward effects attributable to HES. It is concluded that HES is a safe, cheap, and effective plasma substitute for volume replacement following cardiac surgical procedures.