Perioperative transfusion study (PETS): Does a liberal transfusion protocol improve outcome in high-risk cardiovascular patients undergoing non-cardiac surgery? A randomised controlled pilot study.

Background: Small studies have shown that patients with advanced coronary artery disease might benefit from a more liberal blood transfusion strategy. The goal of this pilot study was to test the feasibility of a blood transfusion intervention in a group of vascular surgery patients who have elevated cardiac troponins in rest.

Methods: We conducted a single-centre, randomised controlled pilot study. Patients with a preoperative elevated high-sensitive troponin T undergoing non-cardiac vascular surgery were randomised between a liberal transfusion regime (haemoglobin >10.4 g/dL) and a restrictive transfusion regime (haemoglobin 8.0-9.6 g/dL) during the first 3 days after surgery. The primary outcome was defined as a composite endpoint of all-cause mortality, myocardial infarction or unscheduled coronary revascularization.

Results: In total 499 patients were screened; 92 were included and 50 patients were randomised. Postoperative haemoglobin was different between the intervention and control group; 10.6 versus 9.8, 10.4 versus 9.4, 10.9 versus 9.4 g/dL on day one, two and three respectively (p < 0.05). The primary outcome occurred in four patients (16%) in the liberal transfusion group and in two patients (8%) in control group.

Conclusion: This pilot study shows that the studied transfusion protocol was able to create a clinically significant difference in perioperative haemoglobin levels. Randomisation was possible in 10% of the screened patients. A large definitive trial should be possible to provide evidence whether a liberal transfusion strategy could decrease the incidence of postoperative myocardial infarction in high risk surgical patients.