Diaphragmatic Atrophy in Children Undergoing Mechanical Ventilation After Cardiac Surgery

OBJECTIVE: This study aimed to evaluate the frequency and severity of diaphragmatic atrophy in pediatric patients undergoing mechanical ventilation in the postoperative period of cardiac surgery. METHODS: A prospective cohort study was conducted in pediatric cardiac surgery patients between April and November 2022. Diaphragmatic function was assessed by ultrasound at four time points: pre-operative, immediate post-operative, late post-operative, and prior to extubation. Diaphragmatic thickness, excursion, and maximum inspiratory pressure were measured. Patients were followed for detection of diaphragm atrophy. Statistical analysis included descriptive statistics, parametric and nonparametric tests, and logistic regression. RESULTS: The study included 50 children (median age 1.3 months). Diaphragmatic atrophy was identified in 56% of patients, reaching 63.3% in those on MV for >7 days. Extubation failure occurred in 32%. Although diaphragmatic atrophy did not independently predict extubation failure, multivariate analysis revealed that diaphragmatic thickening fraction (dTF) was independently associated with extubation success [OR 0.934 (95% CI 0.874-0.984, p = 0.023)], alongside maximum inspiratory pressure [OR 0.86 (95% CI 0.77-0.96, p = 0.007)]. CONCLUSIONS: Diaphragm atrophy is a significant and early complication in pediatric cardiac surgery patients. While atrophy alone did not predict weaning outcomes in this cohort, a higher dTF was independently associated with extubation success, suggesting that dTF may serve as a functional marker of weaning readiness in this population.