[Changes in total and differential leukocyte counts during heart surgery with extracorporeal circulation]

The changes in leukocyte overall and differential counts during anesthesia and surgery were evaluated in 24 patients scheduled for cardiac surgery with cardiopulmonary bypass. All the end of cardiopulmonary bypass a marked and sustained leukocytosis was found (10.2 and 11.1 x 10(9).l-1), which was significantly different from baseline values (6.7 x 10(9).l-1), the values previous to cardiopulmonary bypass (6.2 and 6.4 x 10(9).l-1, and the values 30 minutes after it (5.3 x 10(9).l-1). In the differential count there were significant increases in neutrophils, associated with band and immature forms, corresponding with significant reductions in lymphocytes. There was no significant association of leukocyte variability during and after cardiopulmonary bypass and the perfusion time, the type of oxygenator or the need for intraoperative transfusion. All the reported changes tended to become normal during the first postoperative days.