Zhao 2003.

Methods	Randomised controlled trial was conducted to determine the safety and effectiveness of autotransfusion of shed mediastinal blood after open heart surgery. Between January 2000 and October 2000, patients undergoing primary elective coronary artery bypass graft (CABG) surgery were enrolled in this randomised controlled trial. Method of randomisation and allocation concealment were unclear. Participants were not blind to treatment allocation and blinding of the outcome assessor was unclear.
Participants	60 patients undergoing elective primary coronary artery bypass graft surgery were randomly allocated to one of two groups: Group 1 (Autotransfusion group): n=30; M/F=26/4; mean (sd) age = 59.5 (8.0) years Group 2 (Control group): n=30; M/F=27/3; mean (sd) age = 59.2 (8.2) years Exclusion criteria: bleeding time more than 10 minutes due to anti‐coagulant use; pre‐operative left ventricular ejection fraction (LVEF) less than 0.40; diabetes; pulmonary or renal disease.
Interventions	Group 1: Autotransfusion group patients received non‐washed shed mediastinal blood re‐transfused post‐operatively after CABG using a cell saver device (Beijing PerMed Biomedical Engineering Company) up to 18 hours post‐surgery. Shed blood not returned within 4 hours was discarded and a new bag attached. When more than 200mls of shed mediastinal blood was collected within 4 hours the patients received autologous blood if volume replacement was considered necessary. Extracorporeal blood was routinely returned to patients after CABG. Group 2: Control group received banked allogeneic blood only. Autotransfusion was not used. Extracorporeal blood was routinely returned to patients after CABG.
Outcomes	Outcomes reported: number of patients transfused allogeneic blood, volume of allogeneic blood transfused, number of patients transfused autologous blood, volume of autologous blood transfused, blood loss.
Notes	Transfusion threshold: transfusion protocol for allogeneic blood transfusion 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