Autotransfusion of washed shed mediastinal fluid decreases the requirement for autologous blood transfusion following cardiac surgery: a prospective randomized trial

Objectives: The National Blood Service issues 2.2 million units of blood per year, 10% of these (220 000) are utilized in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate, We test the efficacy of autotransfusion following surgery in a prospective randomized trial. Methods: One hundred and twelve patients undergoing CABG, valve or CABG + valve procedures were randomized into two groups. Group A received washed postoperative drainage fluid and group C were controls. The indication for transfusion was a postoperative haemoglobin (Hb) < 10 g/l or a PCV < 30. There was no significant difference in preoperative and operative variables between the groups. Results: Twenty-eight patients in group A and 46 in group C required homologous transfusion (P = 0.0008). Group A patients required 298 +/- 49 ml of banked blood per patient, group C 508 +/- 49 ml (P = 0.003). There was no difference in total blood required (volume autotransfused + volume banked blood transfused) between the groups (group A 404 +/- 50 ml, group C 508 +/- 50 ml) or in mean total mediastinal fluid drainage (group A 652 +/- 51 ml, group C 686 +/- 50 ml). The mean Hb concentration was significantly higher in group A on day 1 (11.2 g/dl +/- 51 vs. 10.6 g/dl +/- 13 (P = 0.002)). No morbidity was associated with autotransfusion. Conclusion: Autotransfusion can decrease the amount of homologous blood transfused following cardiac surgery. This represents a benefit to the patient and a decrease in cost to the health service. (C) 1999 Elsevier Science B.V. All rights reserved.