Platelet Transfusion After Cardiac Surgery

Objectives: To investigate the independent association of platelet transfusion with hospital mortality and key relevant clinical outcomes in cardiac surgery. Design: A single-center, propensity score-matched, retrospective, cohort study. Setting: At an American tertiary teaching hospital data from the Medical Information Mart for Intensive Care III and IV databases from 2001 to 2019. Participants: Consecutive adults undergoing coronary artery bypass graft and/or cardiac valvular surgery. Interventions: Platelet transfusion during perioperative intensive care unit (ICU) admission. Measurements and Main Results: Overall, 12,043 adults met the study inclusion criteria. Of these, 1,621 (13.5%) received apheresis-leukoreduced platelets, with a median of 1.19 units per recipient (IQR: 0.93-1.19) at a median of 1.78 hours (IQR: 0.75-4.25) after ICU admission. The platelet count was measured in 1,176 patients (72.5%) before transfusion, with a median count of 120 × 10⁹/L (IQR: 89.0-157.0), and only 53 (3.3%) had platelet counts below 50 × 10⁹/L. After propensity matching of 1,046 platelet recipients with 1,046 controls, perioperative platelet transfusion carried no association with in-hospital mortality (odds ratio [OR]: 1.28; 99% CI: 0.49-3.35; p = 0.4980). However, it was associated with a pattern of decreased odds of suspected infection (eg, respiratory infection, urinary tract infection, septicaemia, or other; OR: 0.70; 99% CI: 0.50-0.97; p = 0.0050), days in the hospital (adjusted mean difference [AMD]: 0.86; 99% CI: -0.27 to 1.98; p = 0.048), or days in intensive care (AMD 0.83; 99% CI: -0.15 to 1.82; p = 0.0290). Conclusions: Platelet transfusion was not associated with hospital mortality, but it was associated with decreased odds of suspected infection and with shorter ICU and hospital stays.