Association between Thrombocytopenia and Outcomes in Patients Undergoing Redo Valvular Surgery Utilizing Cardiopulmonary Bypass

Objective: To figure out the incidence of postoperative thrombocytopenia among adult cases undergoing redo valvular surgery with cardiopulmonary bypass (CPB) and to discern its ramifications on early postoperative outcomes. Methods: A cohort comprising 188 cases undergoing redo valvular surgery with CPB between March 2018 and July 2023 was analyzed. It was attempted to stratify cases into two groups on the basis of presence of thrombocytopenia that was defined as a nadir platelet count <71 x 10(3)/<mu>L within 72 hours (n = 45), or absence of thrombocytopenia (n = 143). Comparative evaluation was performed concerning postoperative mortality and morbidity. Logistic regression models were employed to unveil the relationship of thrombocytopenia with clinical outcomes. Results: Thrombocytopenia manifested in 45 (23.94%) cases. Univariate analysis disclosed a significant association of percent change in platelet count with mortality (odds ratio (OR), 1.039, 95% confidence interval (CI), 1.005 to 1.074, p = 0.024), postoperative pneumonia (OR, 1.058, 95% CI, 1.023 to 1.095, p = 0.001), prolonged mechanical ventilation (OR, 1.048, 95% CI, 1.026 to 1.071, p < 0.001), extended intensive care unit (ICU) stay (OR, 1.029, 95% CI, 1.010 to 1.049, p = 0.003), protracted post-operative hospitalization (OR, 1.031, 95% CI, 1.011 to 1.051, p = 0.002), postoperative renal replacement therapy (OR, 1.042, 95% CI, 1.017 to 1.069, p = 0.001), and re-thoracotomy attributable to hemorrhage (OR, 1.040, 95% CI, 1.000 to 1.080, p = 0.047). Multivariate analysis demonstrated that thrombocytopenia, regarded as a categorical variable, was independently correlated with an escalated likelihood of prolonged postoperative hospital stay (OR, 4.926, 95% CI, 1.740 to 13.948, p = 0.003). Conclusions: Thrombocytopenia appeared to be closely linked to escalated in-hospital mortality and postoperative morbidity rates among cases undergoing redo valvular surgery employing CPB. Further investigations with larger, prospective cohorts are essential to validate these outcomes and unravel potential underlying mechanisms.