Predictive Factors of Prolonged Mechanical Ventilation After Complete Atrioventricular Septal Defect Surgery

<b>Background:</b> A subset of patients undergoing complete atrioventricular septal defect (AVSD) repair underwent prolonged postoperative mechanical ventilation, contributing to extended intensive care unit and hospital stays. This study evaluated perioperative predictors of prolonged ventilation following complete AVSD repair and explored the utility of Brixia scores for early risk stratification. <b>Methods:</b> We performed a retrospective review of complete AVSD repairs in patients who were <12 months of age at a single academic hospital. Patients with heterotaxy syndrome and airway abnormality were excluded. Demographic, perioperative, partial pressure of oxygen (PaO₂) and fraction of inspired oxygen (FiO₂) ratios (P/F ratio), imaging, and echocardiographic data were collected. Factors associated with prolonged duration of mechanical ventilation (≥24 h) were identified. <b>Results:</b> We included 129 patients for analysis. Patients were divided based on the duration of mechanical ventilation (≥24 and <24 h). The prolonged mechanical ventilation group had a significantly lower median [interquartile range] P/F ratio after cardiopulmonary bypass (102.0 [70.0-180.0] vs 172.5 [79.4-265.0], <i>P</i> = .048). Factors associated with prolonged mechanical ventilation from the multivariable analysis were preoperative Brixia scores and first 24-h postoperative fluid balance. <b>Conclusions:</b> Perioperative factors can be used to identify patients with an increased risk of prolonged ventilation after complete AVSD repairs. The P/F ratios and Brixia scores are useful as early predictors. Postoperative fluid management is a modifiable factor to reduce mechanical ventilation duration.