Methods |
Patients undergoing elective abdominal aortic aneurysm (AAA) repair or aortofemoral bypass (AFB) for occlusive disease were eligible for entrance into the study. Randomisation was carried out in blocks of 10 stratified for AAA repair or AFB. Patients were randomised by means of drawing sealed envelopes that contained prescriptions for either intra‐operative autotransfusion (IAT) or control therapy. The study was unblinded. |
Participants |
100 patients undergoing aortic surgery were randomly allocated to one of two groups:
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Interventions |
Group1: Intra‐operative autotransfusion group had their blood processed by either a Cell Saver 3 Plus or Cell Saver 5 device. Both systems consist of polyvinyl aspiration tubing with a separate channel for introducing small amounts of heparised saline solution to anticoagulate aspirated blood, a plastic cardiotomy reservoir with microaggregate filter, a continuous flow, disposable washing bowl driven by a centrifuge, and a transfusion setup that consists of a plastic transfer pack passed to the anaesthesiologist for administration. The maximum allowable amount of IAT‐PRBCs administered to a single patient was 1500mls.
Group 2: Control group did not receive autotransfusion.
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Outcomes |
Outcomes reported: number of patients transfused allogeneic blood, amount of allogeneic blood transfused, blood loss, hospital length of stay, ICU length of stay, adverse events. |
Notes |
Transfusion threshold: patients were transfused allogeneic RBCs intra‐operatively if the haemoglobin level was less than 10.0g/dL. Post‐operatively patients were transfused allogeneic RBCs if the haemoglobin level was less than 8.0g/dL. |
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) |
High risk |
Treatment allocation was inadequately concealed. |
Blinding (performance bias and detection bias)
All outcomes |
High risk |
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