Very few commonly used neonatal surgical therapies have been evaluated to determine their safety. Premature infants are especially vulnerable to unrecognized treatment hazards. Inguinal hernia (IH) repair is the most commonly performed major operation in premature infants, is associated with a 30-40% morbidity rate, and it is unknown whether the operation should occur prior to neonatal intensive care unit (NICU) discharge or be delayed. Early IH repair possibly increases anesthesia and cardiorespiratory serious adverse events (SAEs), whereas delayed IH repair possibly increases hernia-related adverse events. A growing concern is the possibility that early general anesthesia exposure impairs neurodevelopment. The randomized clinical trial (RCT) proposed will be the first trial to evaluate the effect of timing of general anesthesia exposure on neurodevelopmental outcomes. Our objective is to conduct a 19 center RCT to determine whether early IH repair (prior to NICU discharge) or late IH repair (~5 months after NICU discharge) is the safer surgical approach for premature infants who are diagnosed with an inguinal hernia while in the NICU. Assuming a 60% randomization rate, which is supported from a feasibility pilot RCT, 651 infants will be randomly assigned to early or late IH repair over a 2.5-year period. The primary hypothesis is that late IH repair is safer as defined by a 10% absolute reduction in the proportion of infants with >1 SAE (relative risk = 0.66; number needed to harm of 10 for early repair) within 10 months after enrollment. The primary outcome, as adjudicated by a committee masked to treatment group assignment, is the proportion of infants with >1 SAE during the study period. Secondary outcome measures include the number of hospital days during the study period (hypothesis: median 3 days less with late IH repair) and, in selected centers (n=200 infants), neurodevelopmental testing with the Bayley Scales of Infant Development (BSID), 3rd edition, at 2 years corrected age (hypothesis: 0.4SD higher Cognitive Composite score with late IH repair). We will also measure non-routine events during the IH repair operation, which may underlie SAEs. The potential differences in treatment effect according to pre-specified patient characteristics (at enrollment) will be examined by frequentist and conservative Bayesian methods. The trial is utilizing the Pediatric Surgery Research Collaborative, a cooperative group committed to performing prospective clinical studies in pediatric surgery. Successful completion of the RCT proposed will stimulate future safety studies within neonatal surgery.

Public Health Relevance

We are proposing a multi-center randomized clinical trial to compare the short and longer-term safety of early inguinal hernia repair (prior to neonatal intensive care unit discharge) versus late repair (~5 months after discharge). The main outcomes of the trial are: the proportion of infants that have at least one serious adverse event, the total number of hospital days during the study period, and the neurological outcome at ~2 years corrected age. Our goals are to decrease the rate of adverse events after inguinal hernia repair in premature infants and to increase understanding of the impact of the timing of anesthesia on neurocognitive outcomes

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project--Cooperative Agreements (U01)
Project #
5U01HD076733-02
Application #
8931009
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Raju, Tonse N
Project Start
2014-09-22
Project End
2016-04-29
Budget Start
2015-06-01
Budget End
2016-04-29
Support Year
2
Fiscal Year
2015
Total Cost
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Surgery
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37240
Gulack, Brian C; Greenberg, Rachel; Clark, Reese H et al. (2018) A multi-institution analysis of predictors of timing of inguinal hernia repair among premature infants. J Pediatr Surg 53:784-788