Critical value of platelet transfusion to reduce the risk of death in aortic dissection (AD) patients: a study based on the MIMIC-IV database

Background Platelet transfusion rate is associated with mortality in patients with AD. However, the relationship between platelet transfusion rate thresholds and the risk of death in patients with AD remains to be determined.Methods We reviewed a total of 443 patients with AD. Patients were divided into two groups [≤144.75 mL/h (N = 178) and >144.75 mL/h (N = 265)] on the basis of platelet transfusion rate thresholds analysed via characteristic curves. The correlation between platelet count and long-term mortality was assessed via Cox survival analysis. In addition, we used a generalised additive model (GAM) with a restricted cubic spline (RCS) to explore the nonlinear relationship between platelet transfusion rate and outcome.Results Subjects with high platelet transfusion rate had significantly lower in-hospital mortality. Univariate Cox analysis revealed that a platelet transfusion rate greater than 144.75 mL/h was a significant factor for reducing death (corrected HR = 0.38, 95% CI, 0.22–0.64; p < 0.01). Multivariate Cox analysis demonstrated that platelet transfusion rate of >144.75 mL/h was a significant factor in reducing death (corrected HR = 0.34, 95% CI, 0.18–0.64; p < 0.01). Kaplan–Meier curve analysis further demonstrated that platelet transfusion rate of >144.75 mL/h was a significant factor in reducing death (p < 0.01).Conclusion A platelet transfusion rate of 144.75 mL/h was the inflection point for the risk of death in patients with AD, whereas a platelet transfusion rate of 282.5 mL/h was the nadir for the risk of in-hospital death.