Population
Adult cardiac surgery patients who were at high risk of platelet transfusion, enrolled in the CLIP-NZ Pilot study (n= 89).
Intervention
Cryopreserved platelet transfusion (n= 49).
Comparison
Liquid-stored platelet transfusion (n= 40).
Outcome
The primary outcome was protocol safety and feasibility. Over 13 months, 89 patients were randomized, 23 (25.8%) of whom received a platelet transfusion. There were no differences in median blood loss up to 48 hours between study groups, or in the quantities of study platelets or other blood components transfused. The median platelet concentration on the day after surgery was lower in the cryopreserved platelet group (122 × 10(3) /μl vs. 157 × 10(3) /μl, median difference 39.5 ×10(3) /μl). There were no differences in any of the recorded safety outcomes, and no adverse events were reported on any patient. Multivariable adjustment for imbalances in baseline patient characteristics did not find study group to be a predictor of 24 hours blood loss, red cell transfusion or a composite bleeding outcome.