Prolonged mechanical ventilation (PMV) after major cardiac surgery is associated with increased morbidity, mortality, and healthcare utilization.

To determine independent perioperative predictors of PMV and assess its impact on postoperative outcomes in cardiac surgical patients.

This retrospective case-control study analyzed 1437 adults undergoing major cardiac surgery in 2022. PMV was defined as ventilation >24 h postoperatively. Multivariable logistic regression identified independent predictors; outcomes were adjusted using inverse probability of treatment weighting.

PMV occurred in 167 patients (11.6%). Independent preoperative predictors were mechanical ventilation (OR 5.632, 95% CI 1.208–26.262, P = 0.028) and urgent admission (OR 2.520, 95% CI 1.292–4.844, P = 0.007). Intraoperative predictors included prolonged cardiopulmonary bypass duration and aortic surgery. Postoperative factors associated with PMV were neurologic complications (OR 3.90, 95% CI 1.771–8.590, P = 0.001), acute kidney injury (OR 3.548, 95% CI 1.214–10.374, P = 0.021), transfusion volume (OR 1.043, 95% CI 1.016–1.071, P = 0.002), and continuous sedation duration (OR 1.038, 95% CI 1.026–1.050, P < 0.001). Delirium by Confusion Assessment Method – ICU was not significant (P = 0.053), whereas higher Numeric Rating Scale pain scores were inversely associated with PMV (OR 0.81, 95% CI 0.694–0.945, P = 0.008). PMV was linked to higher reintubation, higher ICU readmission, longer ICU stay (mean difference [MD] 7.4 d, P < 0.001), and extended hospitalization (MD 17.4 d, P < 0.001).

PMV is associated with multiple modifiable perioperative factors and adverse outcomes. Early risk stratification and targeted preventive strategies may improve recovery and survival in this population.