Abstract
BACKGROUND: Despite advancements in surgical techniques and intensive care management, the incidence of prolonged mechanical ventilation (PMV) following cardiac surgery remains a significant concern. OBJECTIVES: Investigate the relationship between the Systemic Inflammation Index (SII) and the occurrence of PMV, as well as the medium-term prognostic outcomes in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). METHODS: This retrospective observational study was conducted at Nanjing First Hospital, including data from adult patients who underwent CPB for cardiac surgery between January 2020 and December 2020. PMV was defined as mechanical ventilation lasting more than 24 h post-surgery. Clinical characteristics, including demographic data and preoperative biomarkers, were collected. Statistical analyses included univariate and multivariate logistic regression to identify predictors of PMV. RESULTS: A total of 1128 patients were included in the final analysis. Higher SII levels were associated with an increased likelihood of PMV and longer hospital stays. Multivariate logistic regression identified several independent predictors of PMV, including age, female gender, chronic lung disease, preoperative SII, and intraoperative plasma infusion. The risk of PMV increased by 7% for every 100-unit increase in SII. Kaplan-Meier survival analysis indicated that patients with PMV had higher mid-term mortality rates, and those with elevated preoperative SII levels exhibited lower survival rates. CONCLUSION: This study demonstrates that elevated preoperative SII is a significant predictor of PMV following cardiac surgery. Identifying patients at risk for PMV can aid in developing individualized treatment strategies and improving postoperative outcomes.