抄録
A comparative study on coagulopathy and platelet dysfunction in patients undergoing cardiovascular surgery with normo- and hypothermic cardiopulmonary bypass (CPB) was performed using Sonoclot signature determinations. Forty-six patients were divided into two groups : 19 had normothermic CPB (group A) ; and 27 had hypothermic CPB and circulatory arrest (group B) . Sonoclot signatures were recorded before the start of CPB and after heparin neutralization after weaning from CPB. Son ACT (active clotting time) and clot rate were analyzed as parameters for coagulopathy, and time-to-peak and peak angle for platelet dysfunction. Significant prolongation of Son ACT and a lower clot rate after CPB were found in group B, though the protamine dose for heparin neutralization was identical to that of group A. Time-to-peak was also significantly prolonged, and platelet loss was greater in group B. Blood loss during surgery was significantly greater in group B, however significant differences could not be detected in postoperative blood loss when the abnormal Sonoclot signatures were corrected to baseline levels by supplemental use of fresh frozen plasma or platelet concentrate. More profound coagulopathy and platelet loss and dysfunction develop in hypothermic CPB and circulatory arrest than in normothermic CPB. Sonoclot® measurement quickly gives reliable information regarding abnormal coagulability and platelet dysfunction after CPB. Excessive blood loss might be prevented postoperatively by correcting abnormal Sonoclot signatures to a baseline level by appropriate choice of hemostatic therapy.