Storage duration of platelet concentrates and clinical outcomes in cardiac surgery patients.

Background: The changes in platelet structure and function arising from its collection and storage are collectively called "platelet storage lesion." In patients this might potentially be associated with impaired hemostasis and adverse events. We performed a hypothesis-generating retrospective study in cardiac surgery patients transfused with platelets in two hospitals between 2005 and 2017.

Study design and methods: We explored whether longer storage duration of platelets is associated with changes in in-hospital mortality, blood loss after surgery, reoperation for bleeding, stroke, myocardial infarction, infection, systemic inflammatory response syndrome, shock, and multi-organ failure in cardiac surgery patients. Platelet concentrates were classified as platelets with shorter storage duration (PSSD; stored 1-3 days) or platelets with longer storage duration (PLSD; stored 4-7 days). Associations between storage duration and endpoints were quantified using logistic regression adjusted for potential confounders.

Results: In patients transfused with PLSD, in-hospital mortality (212/2117; 10.0%) was significantly higher than in patients transfused with PSSD (109/1439; 7.6%) (adjusted odds ratio [aOR] 1.47, 95% confidence interval [CI] 1.13-1.91). Patients transfused with PLSD experienced postoperative blood loss ≥1000 mL (102/285; 35.8%) significantly more frequently than patients transfused with PSSD (87/326; 26.7%), aOR 1.74 (95% CI 1.19-2.52). In patients transfused with PLSD, the need for reoperation for bleeding (99/285; 34.7%) was significantly higher than in patients transfused with PSSD (87/326; 26.7%) (aOR 1.62, 95% CI 1.12-2.35). There was no notable association with other endpoints.

Conclusion: In cardiac surgery patients, transfusion of PLSD was associated with higher in-hospital mortality, more blood loss, and reoperations for bleeding, compared to transfusion of PSSD.