Postoperative autologous transfusion in cardiac surgery. A prospective, randomised study

To investigate the safety and efficacy of postoperative autologous bloodtransfusion (AT) using the Shiley hardshell venous reservoir, aprospective, randomised, controlled study was carried out in two matchedgroups of twenty patients undergoing elective coronary artery bypasssurgery. The mean volume of shed mediastinal blood reinfused in the first 6h postoperatively was 371.7 +/- 63.23 ml. Use of homologous blood wasreduced from 760.5 +/- 108.37 ml in the control patients to 466.25 +/-87.44 ml in the AT patients, a reduction of 38.7% (p less than 0.05). Therewas no statistically significant difference in the clinical outcome,overall blood loss, use of platelets, fresh frozen plasma and colloids,haematological indices, renal and hepatic functions, or clotting mechanism,although there was a reduction in the fibrinogen level in the patients whoreceived AT (p less than 0.05). Mediastinal blood did not clot and wasdefibrinogenated. It contained significant levels of haemoglobin (8.175 +/-0.506 g/dl), platelets (96.55 +/- 10.39 per mm3 10(3)), protein (42.5 +/-1.13 g/l), calcium (2.385 +/- 0.054 mmol/l) and was well oxygenated (PO2 =20.46 +/- 0.81 kPa). No patients developed bacteraemia or had anyAT-related infections. We conclude that postoperative autologoustransfusion using the Shiley hardshell venous reservoir is a safe andefficient method for reducing postoperative homologous blood requirementafter coronary artery bypass surgery.