Preoperative and intraoperative risk factors for impaired pulmonary oxygenation after cardiopulmonary bypass: a single-center retrospective analysis
摘要
Postoperative pulmonary dysfunction is a frequent complication after cardiopulmonary bypass (CPB). Identifying preoperative and intraoperative risk factors for impaired oxygenation is essential for perioperative optimization.
MethodsA retrospective analysis was conducted on 202 patients who underwent open-heart surgery with CPB at Kumamoto University Hospital between June 2022 and October 2024. Patients were categorized into two groups on the basis of the partial pressure of oxygen (PaO2)/ Fraction of Inspired Oxygen (FiO₂) ratio (P/F ratio) from arterial blood gas analysis under FiO₂ 1.0 at intensive care unit (ICU) admission: impaired oxygenation (P/F < 300) and normal oxygenation (P/F ≥ 300). Multivariate logistic regression was used to identify risk factors for impaired pulmonary oxygenation.
ResultsOf the 202 patients, 53 (26%) developed impaired oxygenation. Multivariate analysis revealed high preoperative body mass index (BMI), a history of hypertension, and an elevated preoperative respiratory index (RI) as independent predictors. The model showed good discrimination (Area Under the Curve (AUC) = 0.746, 95% CI: 0.669–0.823) and calibration.
ConclusionsPreoperative RI, BMI, and hypertension are significant predictors of impaired oxygenation after CPB. RI, a readily accessible metric derived from arterial blood gas analysis, may be integrated into routine preoperative assessments to identify high-risk patients and guide tailored lung-protective strategies.
Trial registrationThe study was approved by the Ethics Committee of Kumamoto University Hospital (Approval No. 3040). The approval date is August 30, 2024.