Optimal Timing of Inguinal Hernia Repair in Premature Infants: A NSQIP-P Study

Introduction: Among premature infants, the incidence of inguinal hernias is reported to be as high as 30%. Despite being one of the most commonly performed procedures, the optimal setting of inguinal hernia repair (IHR) that is inpatient versus outpatient remains debatable. We sought to compare the 30-day outcomes of each approach by querying the National Surgical Quality Improvement Program-Pediatric database.

Materials and methods: A retrospective cohort study comparing inpatient versus outpatient IHR using the National Surgical Quality Improvement Program-Pediatric database from 2013 to 2019 was performed. Demographic and clinical data were initially compared using univariate analysis. Continuous variables are presented as median and interquartile range and categorical variables are presented as n (%). Subsequently, cohorts were propensity matched using clinically and statistically significant patient characteristics.

Results: 928 patients underwent IHR, 634 (68.3%) while inpatient, 294 (31.7%) following hospital discharge. Inpatient IHR was associated with lower age at the time of surgery (120 versus 147 d; P < 0.0001), younger gestational age (27 versus 33 wk; P < 0.0001), decreased probability of repair in elective setting (87.2% versus 97.3%; P < 0.0001), and increased preoperative supplemental oxygen need (42% versus 4.4%; P < 0.0001). Comparison of propensity matched cohorts revealed that inpatient IHR was associated with increased procedure time (82 versus 51 min; P < 0.0001) and anesthetic duration (146 versus 102 min; P < 0.0001), wound infection rates (3.8% versus 0%; P = 0.007), blood transfusions (4.2% versus 0.5%; P = 0.036), unplanned intubations (2.8% versus 0%; P = 0.03), ventilator days (0 versus 0; range [0,30 versus 0,2]; P = 0.002), reoperation rate (5.6% versus 0%; P < 0.001), postoperative hospital length of stay (4 versus 1 d; P < 0.0001), and unplanned readmissions (8.9% versus 0.9%; P = 0.002).

Conclusions: Inpatient IHR in premature neonates were associated with different postoperative outcomes than outpatient IHR. At least in the elective setting among premature infants, outpatient IHR can be considered safe in select patients while we await higher quality prospective data.