Risk factors for prolonged mechanical ventilation in neonates following gastrointestinal surgery

Prolonged mechanical ventilation (MV) should be avoided in neonates. Noninvasive ventilation (NIV) can facilitate weaning from MV but has risks for patients immediately following foregut surgery due to the potential risk of anastomotic leak. We evaluated the risk factors for prolonged MV following intestinal surgery in neonates.

We retrospectively reviewed 253 neonates undergoing intestinal surgery in 2017-2018 to identify risk factors for prolonged MV, and determine the correlation between NIV and anastomotic leak in a tertiary neonatal intensive care unit that performs the greatest number of neonatal surgeries in Ontario.

The most common diagnoses were necrotizing enterocolitis/spontaneous intestinal perforation (NEC/SIP) 21%, intestinal atresia 16%, esophageal atresia/tracheoesophageal fistula 14%, ano-rectal malformation 13%, malrotation/volvulus 11%, gastroschisis 9% and omphalocele 4%. The median (IQR) duration of MV post-surgery was 3 (1-8) days with 25.7 % (n=65) of neonates on MV for >7 days. Compared to infants on MV post-surgery for ≤7 days, those with MV>7 days were of lower gestational age, birth weight and weight at surgery, but a higher proportion underwent stoma creation, had a longer duration of opioid administration and higher rates of moderate to severe bronchopulmonary dysplasia (BPD) and mortality (P<0.05). Generalized linear regression analysis showed lower gestational age (GA) and longer opioid administration were associated with longer duration of MV (P<0.001), but indication for surgery, weight at surgery and stoma creation didn't correlate with longer duration of MV (P>0.05). Of the 122 patients handled by one-stage resection with primary anastomosis, 22.1% (n=27) received NIV with 74.1% (n=20) commenced on NIV after 7 days post-surgery, anastomotic leak was detected in 2.5 % (3/122) patients and didn't correlate with NIV.

Lower GA and longer opioid administration were risk factors for prolonged MV in neonates following intestinal surgery. Further research is needed to investigate modifiable practices around pain assessment/ventilation in these patients, and the correlation between NIV and anastomotic leak.