Parrot 1991.

Study characteristics
Methods	Design: RCT, parallel three‐arm, single‐centre study Setting: university teaching hospital, Dijon, France Recruitment: recruitment and study dates not reported Maximum follow‐up: postoperative
Participants	66 participants undergoing aortocoronary bypass surgery were randomly assigned to one of three groups: Group 1 (control group): N = 22. Mean age = 61 years Group 2 (intraoperative cell salvage): N = 22. Mean age = 60 years Group 3 (intraoperative and postoperative cell salvage): N = 22. Mean age = 55 years There were no differences between groups with respect to age, sex, body surface area, preoperative haematocrit, and bypass duration.
Interventions	Group 1 (Control group): control group participants received homologous blood transfusion only. Group 2 (intraoperative cell salvage): cell salvage group received intraoperative autologous blood. Intraoperative autologous blood consisted of the blood contents of the oxygenator after concentration but without any washing, by the Haemonetics Cell Saver III autologous transfusion system. Group 3 (intraoperative and postoperative cell salvage): cell salvage group received intraoperative and postoperative autologous blood. Postoperative autologous blood consisted of the mediastinal blood shed during the first 6 hours, into a heparinised drainage system (PLEUR‐EVACA 4005) which was concentrated and washed by a Haemonetics Haemolite system.
Outcomes	Outcomes reported: amount of blood re‐transfused from the cell saver, amount of allogeneic blood transfused, number of participants transfused allogeneic blood, adverse events, mortality, blood loss, Hct levels
Notes	Transfusion protocol: allogeneic blood transfusions were given if the haematocrit dropped below 20% during bypass, 28% at the end of the procedure, 30% within 24 hours, or if the haemoglobin level was < 10.0 g/dL while on the cardiac surgery ward (8 to 10 days). Prospective registration status: the study was published prior to 2010. Ethical approval: it is not clear whether the study was approved by an ethics committee or institutional review board. Language of publication: English Study groups: for the purpose of our review, specific groups have been used within our subgroup analyses for cell salvage timing. Group 2 versus Group 1 has been used within the intraoperative cell salvage subgroup. Group 3 versus Group 1 has been used within the intraoperative and postoperative cell salvage subgroup. Trial funding: not reported Conflicts of interest: 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 unclear.
Blinding of participants and personnel (performance bias) Objective outcome: mortality	Low risk	Objective outcome (mortality) unlikely to be influenced by blinding
Blinding of participants and personnel (performance bias) Subjective: transfusion protocol	Low risk	Transfusion protocol in place: "All patients received HB ('homologous blood') if their hematocrit dropped below 20% during bypass, 28% at the end of the procedure, 30% within 24 hours, or if their hemoglobin level was < 10 g/dL while on the cardiac surgery ward (8 to I0 days)".
Blinding of participants and personnel (performance bias) Subjective: all other outcomes	High risk	No blinding, outcome methods deemed to be at high risk of subjectivity
Blinding of outcome assessment (detection bias) Objective outcomes: mortality and transfusions	Low risk	Objective outcome (mortality) unlikely to be influenced by blinding
Blinding of outcome assessment (detection bias) Subjective outcomes	High risk	No blinding, outcome methods deemed to be at high risk of subjectivity: criteria for diagnosis of infection and method for measuring blood loss not defined
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Only one person excluded (died). Reason for being excluded is death, should therefore have been kept in (mortality outcomes were not reported)
Selective reporting (reporting bias)	Unclear risk	No trial registration or published protocol is available to compare
Other bias	Unclear risk	Some baseline imbalance (group 3 participants are younger, though authors say no statistical difference). No funding or conflicts reported