Effectiveness of autologous blood donation in coronary surgery--a retrospective analysis

Abstract

This study was performed to evaluate whether autologous blood donation prior to coronary artery bypass graft surgery (cabg) reduces homologous blood requirements and the risk of homologous blood transfusion. Within a period of 18 months, 633 patients undergoing cabg surgery were retrospectively included into the study. Non-donors were included if preoperative haemoglobin concentration exceeded 12.5 g%. According to demographic data, risk scores of patients who donated blood (n = 201) were lower. More patients of this group received left internal mammary bypass grafts (63% vs. 51%; p = 0.047). Nevertheless, blood loss did not differ between donors and non-donors. Prior to blood donation, haemoglobin-concentration was significantly higher in male donors (n = 177) compared to female donors (n = 24) (15 +/- 1.2 vs. 13.8 +/- 1 g%; P < 0.001). Compared to female donors, male patients donated significantly more blood units. The risk of homologous blood donation was significantly lower in male donors than in male non-donors (no homologous transfusion: 20% vs. 42%; P < 0.0001; Odds Ratio: 0.34; 95% confidence-interval: 0.23-0.52). Accordingly, homologous blood requirements were lower in male donors (0.9 +/- 3.4 vs. 1.6 +/- 3.6 blood units; P = 0.02). Between female donors and non-donors neither the number of patients treated with homologous blood (no homologous transfusion: 29% vs. 33%, P = 1; odds ratio: 1.17; 95% confidence-interval: 0.4-3.4), nor the mean number of transfused homologous blood units (1.8 +/- 1.6 vs. 1.9 +/- 2.4; P = 0.83) was different. Reactions during blood donation requiring treatment (bradycardia, hypotension, angina, arrhythmias) occurred more often in female patients (5/24 vs. 9/177; P = 0.015). In our study, autologous blood donation significantly decreased the risk of homologous transfusion and homologous blood requirements in male cabg patients. We were not able to prove the efficacy of autologous blood donation in female cabg patients. Due to the small sample size of our investigation, further prospective studies are necessary to answer the question whether patients with low blood volume, body weight and body height scheduled for cabg surgery should be excluded from autologous blood donation.