PM1040: Post-operative Mechanical Ventilation Among Children with Tetralogy of Fallot: Analysis of a Pediatric Health Information System (PHIS) Database Registry

Background: Tetralogy of Fallot (ToF) is one of the most common forms of congenital heart disease. Pre- and post-surgical risk factors associated with complete repair are not clearly defined in the current literature but may increase the risk of mechanical ventilation (MV) and prolonged mechanical ventilation (PMV).

Methods: This multicenter, retrospective study utilized the Pediatric Health Information System database. Patients ≤18 years who underwent a completed TOF repair and were discharged from January 1, 2004, through December 31, 2019, were included. Exclusion criteria consisted of those patients with any congenital heart defect other than TOF, atrial septal defect, and/or patent ductus arteriosus. Among those with TOF, patients with pulmonary valve atresia or complete atrioventricular canal defect were also excluded. Demographics, co-morbid conditions (pre- and postoperative), procedures and outcome data were abstracted and analyzed. The primary outcome was MV utilization (>2 days) after repair; the secondary outcome was PMV, defined as MV ≥10 days after repair. Univariate and multivariate analyses were performed to investigate risk factors associated with utilization of MV and PMV after complete repair of TOF.

Results: Of the 10,000 subjects included in the study, 27% of patients (n=2,701) required MV >2 days and 6.5% (n=645) required PMV (≥10 Days) from post-complete repair. Table 1 (multivariate analysis) shows the pattern of MV across the study group. The average MV use among patients with >2 days was 15.69 days (CI (13.18,18.19)) compared to those who did not (mean: 2.37; CI (2.20, 2.53)). Patients aged 0-30 days old required more MV (mean 9.01 days; CI (7.30, 10.72)) relative to patients aged 91-180 days (2.73 for 91-180 days age). Premature patients required 10.91 mean days (CI (8.69, 13.14) versus term patients (3.27 days).
Risk factors significantly associated with PMV (depicted as OR, 95% CI) on multivariate analysis were: younger age (0-30 days) [3.93 (3.28,4.71)], prematurity [1.95 (1.54,2.48)]; seizures [4.25 (2.65,6.83)] and brain hemorrhage [2.21 (1.36,3.58)]; arrhythmias [1.87 (1.62,2.15)]; cleft lip/palate [1.77(1.23,2.56)], diaphragmatic herniation [3.23 (2.23,4.68)], and necrotizing enterocolitis [4.86 (1.90,12.40)]; chylothorax [2.19 (1.17;4.10)]; acute kidney injury [2.17 (1.67,2.82)]; sepsis [2.07 (1.45,2.93)]; genetic syndromes [1.50 (1.31,1.72)]; preoperative MV [2.16 (1.79,2.61)]; and postoperative CPR [2.39 (1.78,3.21)], cardiac catheterization [1.87 (1.43,2.44)], and pacemaker implantation [1.69 (1.04,2.75)].

Conclusion: Approximately a quarter of TOF patients were mechanically ventilated after primary repair and 6.5% required PMV. We identified unique pre-operative and post operative factors associated with utilization of MV and PMV after complete repair of TOF. This study data enables risk stratification and prognostication for post-operative outcome for clinicians, patients, and caregivers.