Methods	Prospective, randomised controlled trial of patients undergoing coronary artery surgery to compare inflammatory response, myocardial injury, and post-operative bleeding when cardiotomy suction blood and mediastinal shed blood were either discarded or re-transfused. Method of randomisation and allocation concealment were not described
Participants	35 patients undergoing cardiac surgery were randomly allocated to one of two groups: Group 1 (Autotransfusion group): n=12; M//F=9//3; mean (sd) age = 64 (7.0) years Group 2 (Control group): n=17; M//F=16//1; mean (sd) age = 67 (8.3) years NB: Six patients were excluded from the final analysis.
Interventions	Group 1: Autotransfusion group had their cardiotomy suction blood during cardiopulmonary bypass (CPB) and mediastinal shed blood during the first 12 hours post-operatively re-transfused. Group 2: Control group had their cardiotomy suction blood and mediastinal shed blood discarded. NB: All patients received intravenous tranexamic acid (TXA) 2g before surgery and 2g after skin closure
Outcomes	Outcomes reported: number of patients transfused allogeneic blood, volume of shed mediastinal blood, blood loss
Notes	Transfusion threshold: transfusion protocol was not reported.
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used to generate allocation sequences was not described
Allocation concealment (selection bias)	Unclear risk	Method used to conceal treatment allocation was not described
Blinding (performance bias and detection bias) All outcomes	High risk