NCT04574128.

Study name	Retransfusion or not of cardiotomy blood
Methods	Non‐inferiority randomised controlled trial of participants undergoing coronary artery bypass grafting (CABG). Adults aged 18 and over will be randomised to one of two groups. The method of randomisation and allocation concealment is not described. The trial is described as double‐blinded (participants and care providers). The person that controls the heart and lung machine is not masked. Other members of the surgical team are masked.
Participants	Participants will be adults aged over 18 years undergoing elective CABG. The estimated enrolment number is 40 participants across two groups: Experimental arm (Autotransfusion group): N = 20 No intervention arm (Control group): N = 20 Inclusion criteria 18+ years Elective CABG Exclusion criteria Anaemia, infection, massive bleeding, CABG off‐pump
Interventions	Experimental arm (Autotransfusion group): re‐transfusion of cardiotomy blood No intervention arm (Control group): no re‐transfusion of cardiotomy blood
Outcomes	Blood loss, measured according to haemoglobin concentration and blood volume (mL)
Starting date	1 October 2020 Estimated study completion date: 30 December 2022
Contact information	Contact: Camilla Wistrand, PhD +460707686938 camilla.wistrand@regionorebrolan.se
Notes	Transfusion protocol: a transfusion protocol is not described Prospective registration status: study was prospectively registered on ClinicalTrials.gov (date of registration: 05 October 2020) Ethical approval: not known whether the study has been approved by an ethics committee or institutional review board Language: information available on ClinicalTrials.gov is in English Status: Last update posted: 5 October 2020 Recruitment status: not yet recruiting