Mortality after emergency abdominal operations in premature infants

To determine risk of 30-day mortality for premature infants undergoing abdominal operations during the first 2 months of life and to identify risk factors for perioperative mortality using available demographic and clinical variables of interest.

Retrospective descriptive analysis of premature infants (gestational age less than or equal to 36weeks) undergoing abdominal operations during the first 2 months of life using the American College of Surgeon's National Surgical Quality Improvement Project Pediatric (NSQIP-P, 2012-2015) database. A stepwise logistic regression model incorporating multiple demographic and clinical factors was constructed to identify independent predictors of 30-day mortality.

A total of 1554 premature infants were identified who underwent abdominal operations during the first 2 months of life. Unadjusted 30-day mortality ranged from 31% for infants born <24weeks gestational age to 4.9% for those born at 35-36weeks. Increased gestational age corresponded to decreased risk of mortality but week-by-week was not independently predictive of mortality in multivariate modeling. Female sex (aOR 1.51, 95% C.I. 1.08-2.10, p=0.014), inotrope support (aOR 3.46, 95% C.I. 2.43-4.92, p<0.001), ventilator use (aOR 2.86, 95% C.I. 1.56-5.25, p<0.001) and American Society of Anesthesiologists (ASA) class 3 (aOR 4.14, 95% C.I. 1.58-10.81, p=0.004) at time of operation were all associated with significantly increased risk of 30-day mortality. On stepwise logistic regression incorporating only those variables with statistical significance, female sex, inotrope, and ventilator support retained statistical significance.

Premature infants undergoing abdominal operations during the first 2 months of life have expectedly high risk of 30-day mortality. Female sex, inotrope, and ventilator support are independently associated with increased risk of mortality and can be incorporated into a model where, if present, risk of mortality is greater than 14.2%.

Level III.