Effect of Adding Bowel Ultrasound to Standard Radiography for Suspected Necrotizing Enterocolitis: A Randomized Clinical Trial

ImportanceBowel ultrasound (BUS) offers real-time assessment of bowel integrity and perfusion, but its clinical impact on diagnosis and management of necrotizing enterocolitis (NEC) remains unclear. ObjectiveTo evaluate whether adding BUS to standard abdominal radiography (AXR) improves diagnostic decision-making and clinical outcomes in infants evaluated for suspected NEC. DesignRandomized clinical trial. SettingLevel IV neonatal intensive care unit (NICU) of a freestanding childrens hospital (BUS-experienced) and a level III NICU of an adult hospital (BUS-naive). ParticipantsInfants undergoing imaging for suspected NEC. InterventionsInfants randomized by calendar month to AXR alone or AXR + BUS. Clinical management followed standard NICU practice. Main Outcomes and MeasuresThe primary outcome was time to full enteral feeds within 30 days of NEC concern. Secondary outcomes included duration of antibiotics and bowel rest. Analyses followed the intention-to-treat principle, with per-protocol sensitivity analyses. Post-imaging survey assessed the perceived impact of adding BUS on diagnostic and therapeutic decision-making. ResultsA total of 169 infants (199 NEC evaluations; 114 AXR, 85 AXR + BUS) were included; 84% were preterm, and 62% were from the level IV NICU. Among infants ultimately classified as extended NEC rule-out (NEC excluded after repeated imaging evaluations), BUS was associated with faster recovery to full feeds (median 4 vs 8 days; hazard ratio [HR], 1.89; 95% CI, 1.23-2.91). No differences were observed among infants with quick NEC rule-out (NEC excluded after single imaging evaluation) or confirmed NEC. BUS did not prolong antibiotic or bowel rest duration. Per-protocol analysis yielded similar results for all outcomes. Neonatologists reported greater diagnostic and therapeutic confidence with BUS. Conclusions and RelevanceIn this dual-site randomized trial, adding BUS to standard AXR accelerated feeding recovery among infants with prolonged diagnostic evaluations for suspected NEC, without increasing adverse events. BUS may enhance diagnostic confidence and streamline management in cases of diagnostic uncertainty. Larger multicenter studies are warranted to confirm these findings and guide implementation across NICU settings. Trial RegistrationClinicalTrials.gov Identifier NCT05573113 Key PointsO_ST_ABSQuestionC_ST_ABSDoes adding bowel ultrasound to standard radiography improve outcomes among infants evaluated for suspected necrotizing enterocolitis? FindingsIn this randomized diagnostic trial of 169 infants, adding bowel ultrasound shortened time to full feeds among infants with prolonged diagnostic evaluations without increasing adverse events. MeaningBowel ultrasound may enhance diagnostic confidence and expedite feeding recovery in infants with diagnostic uncertainty for NEC.