A standardized universal protocol for using adjunct abdominal ultrasound at the time of diagnosis for suspected necrotizing enterocolitis.

BACKGROUND: Necrotizing enterocolitis (NEC) remains a highly morbid disease for preterm infants. The use of adjunct abdominal ultrasonography improves the evaluation of early or uncertain cases of NEC. No institutions have reported implementing a standardized adjunct abdominal ultrasound guideline and universally adopting adjunct abdominal ultrasound in routine neonatal practice for the evaluation of NEC. OBJECTIVE: To determine if a standardized, adjunct abdominal ultrasound guideline for diagnosing NEC is feasible and beneficial for the routine detection of pathologic abdominal findings in NEC. MATERIALS AND METHODS: This retrospective study was conducted in an 82-bed level IV academic neonatal intensive care unit from February 2023-April 2024. Unit guidelines were updated in February 2023 to recommend the addition of an adjunct abdominal ultrasound to evaluate NEC universally at the time of initial evaluation. Imaging data was abstracted from a post-implementation observation period of 15 months. Implementation feasibility was assessed. Sonographic findings consistent with NEC were described after implementing standardized sonography protocols. RESULTS: Adjunct abdominal ultrasound was performed in 22 of 23 cases (96%) of NEC following guideline implementation. Twenty ultrasounds (90%) had at least one finding suggestive of NEC, and 12 (55%) had multiple findings suggestive of NEC. Seven ultrasounds (32%) showed findings of NEC in cases with unremarkable initial abdominal radiographs. Two NEC cases had radiographic findings without abdominal ultrasound findings. The sensitivity of abdominal ultrasound for NEC was 0.91. In 59% of cases, abdominal ultrasound findings resulted in a higher modified Bell's stage when compared to initial abdominal radiograph findings. CONCLUSION: Implementing a standardized adjunct abdominal ultrasound guideline to assist with the initial diagnostic evaluation of NEC is feasible and may aid in diagnosis of NEC.