Liu 2020.

Methods	Participants undergoing Caesarean section were randomised to one of two groups in a 1:1 ratio and according to a random number table generated by a computer. The research centre then performed random grouping according to their assigned patient identification number. The blinding status of study participants, personnel, and outcome assessors is not described.
Participants	116 women undergoing Caesarean section for both elective and emergency indications were randomised to one of the following two groups: Intraoperative cell salvage (ICS) group (Autotransfusion): N = 58. Mean (SD) age 35.32 (4.61). Mean (SD) weight 67.61 (5.38) kg Control group: N = 58. Mean (SD) age 36.11 (4.83). Mean (SD) weight 68.12 (5.85) kg Participants undergoing Caesarean section for both elective and emergency indications were eligible for inclusion. No subgroup data are provided for the elective Caesarean section participants. We contacted the authors to request this information (15 August 2022).
Interventions	Intraoperative cell salvage (ICS) group (Autotransfusion): an autologous blood recycling machine was installed before the operation. After delivery and placental separation, anticoagulant composed of 25,000 IU of heparin per 1000 mL of 0.9% NaCl solution was drip fed (1 drop/s) into the operation field and allowed to mix with the maternal blood in the operative field. The blood‐saline solution was then recovered using a separate suction tube of an isolation suction system at a vacuum pressure of 20 KPa into a sterile reservoir and centrifuged to allow larger, denser red blood cell cells (RBCs) to cling to the wall of the tube, while all other blood components were discarded directly to the waste bag. RBCs were washed with and resuspended in sterile isotonic sodium chloride (0.9% NaCl) using a blood recycling machine and then infused back into the patient after passing through a white blood cell filter as soon as possible both during and after surgery. Autologous blood was not stored for more than 6 hours. Amniotic fluid was aspirated using another suction unit. Infusion was stopped when haemoglobin concentration reached 80 g/L. If the patient's haemoglobin concentration was still < 80 g/L, allogeneic red blood cells were infused until haemoglobin concentration reached 80 g/L. Control group: allogeneic RBCs were infused when the haemoglobin concentration was < 80 g/L. When the haemoglobin concentration was ≧ 80 g/L, no blood cell transfusion was given. The amount of RBC transfusion depended on the bleeding amount and rate as well as the haemoglobin level.
Outcomes	Outcomes reported: haemoglobin concentration at 30 minutes, 24 hours, 3 days and 7 days after surgery or at discharge; coagulation function (prothrombin time/activated partial thromboplastin time (PT/APTT)) at 24 hours, 3 days and 7 days after surgery or at discharge; results of blood gas analysis at 30 minutes and 24 hours after surgery; blood type antibody screened at 5 days after surgery; use of allogeneic blood products during hospitalisation; occurrence of amniotic fluid embolism, sepsis, acute respiratory distress syndrome (ARDS), disseminated intravascular coagulation (DIC), pulmonary embolism (PE), complications of various organ systems and/or complications related to blood transfusion during the postoperative hospitalisation; hospitalisation time and expenses; complications during follow‐up; completion of the study, death, withdrawal and rejection
Notes	Transfusion protocol: allogeneic RBCs or recovered autologous blood‐washed RBCs after filtration were transfused to patients with haemoglobin < 80 g/L in the control or ICS groups, respectively. Prospective registration status: the study was prospectively registered on the Chinese Clinical Trials Registry (ChiCTR‐ICC‐15007096) (28 September 2015). Ethical approval: the study received approval from the Hospital Ethical Review Committee (No. 2016‐XJS‐003‐01). Language: the study is published in English. Reason for awaiting classification status: participants undergoing Caesarean section for both elective and emergency indications were eligible for inclusion. No subgroup data are provided for the elective Caesarean section participants. We contacted the authors to request this information (15 August 2022).