Intraoperative blood requirements and allogeneic blood transfusion in cardioanesthesia. Data analysis of 7729 patients in 12 cardiac surgical clinics

UNLABELLED: Allogeneic blood requirements in cardiac surgery shows a wide variation even for comparable procedures. The aim of the present study was to compare the intraoperative allogeneic blood requirement in defined cardiac operations among 12 cardiac centers in Germany. METHOD: A data set with 25 variables concerning the intraoperative course in adult cardiac patients with myocardial revascularization, valve replacement (aortic or/and mitral valve) or combined procedures was distributed to the participating centers. The data of all patients between January 1th 1998 and June 30th 1998 were included. Besides demographic data, the intraoperative transfusion of allogeneic and autologous blood, fresh frozen plasma and the concomitant hematocrit values were registered. Data were analyzed for all centers and separated for each center. RESULTS: The data of 7,729 patients were analyzed. The intraoperative allogeneic blood requirement was 0.6 +/- 1.3 units for all patients. It varied among the centers from 0.25 +/- 0.6 units to 0.97 +/- 1.6 units (P < 0.05). The percentage of patients receiving allogeneic blood was 27% and differed among the centers from 17% to 35%. Female patients were transfused in 53% (36-39%) compared to male patients with 16% (9-20%) (P < 0.05). The rate of autologous blood predonation varied from 0.5% to 23%. Patients without autologous predonation were transfused in 28% compared to 4% in patients with predonation (P < 0.05). In patients with autologous predonation the intraoperative transfusion of allogeneic blood was significantly reduced (0.1 +/- 0.39 vs 0.6 +/- 1.4 units, P < 0.05). However, some centers with a high percentage of autologous predonation also demonstrated a high rate of perioperative allogeneic transfusion. CONCLUSION: The incidence of allogeneic blood transfusion in cardiac surgery depends on the institution and not on the surgical procedure. A common threshold value of hemoglobin for the transfusion of blood trigger even for comparable procedures could not be detected among the centers. Especially in female patients, there was a wide variation in allogeneic blood transfusion. Autologous blood predonation reduces blood requirement significantly, however, it is practiced with variing intensity. The data set did not include information about transfusion regimen in the postoperative period, thus, these data do not allow to draw conclusions for the whole perioperative period.