Association of Time Since Diagnosis of Pediatric Ileocolic Intussusception With Success of Attempted Reduction: Analysis in 1065 Patients.

BACKGROUND. Radiologists generally treat pediatric ileocolic intussusceptions emergently given the potential for worse outcomes resulting from delayed reduction attempts. However, the relevant literature is conflicting. OBJECTIVE. The purpose of this study was to identify factors associated with successful image-guided ileocolic intussusception reduction in children, with attention given to the time since diagnosis. METHODS. This retrospective study included patients younger than 6 years old who underwent attempted image-guided enema reduction of ileocolic intussusception between May 2009 and July 2023. Patients were separated into two groups: those who presented directly to the institution (i.e., nontransferred patients, who all underwent attempted reduction < 8 hours after ultrasound diagnosis) and those who transferred to the study institution from outside facilities. EHR data were extracted. Each patient's first image-guided reduction attempt was classified as successful or unsuccessful. Univariable and multivariable analyses were performed. RESULTS. The study included 1065 patients (649 male and 416 female patients; mean age, 18.1 months; age range, 2.2-71.0 months; 793 nontransferred and 272 transferred patients). For nontransferred patients, the mean interval between ultrasound diagnosis and the initial reduction attempt was 150.8 minutes; among transferred patients, the mean interval between advanced imaging at an outside facility (when documented) and the reduction attempt was 460.2 minutes (p < .001). Successful reduction occurred in 84.6% and 81.6% of nontransferred and transferred patients, respectively (p = .25). For nontransferred patients, success occurred in 85.6% of attempts performed less than 2 hours after diagnosis versus 84.0% of attempts performed 2 to less than 8 hours after diagnosis (p = .54); the mean interval from diagnosis to attempted reduction was 149.7 and 156.8 minutes for successful and unsuccessful attempts, respectively (p = .53). In multivariable analysis, factors showing independent associations with success were proximal intussusception location (OR = 3.63, p < .001) and absence of high-risk ultrasound findings (OR = 2.57, p < .001); success was not independently associated with age, sex, bloody stools, reduction method used, or time since diagnosis of less than 2 hours (p > .05). For transferred patients, the mean interval from advanced imaging performed at an outside facility to attempted reduction was 463.1 and 440.2 minutes for successful and unsuccessful attempts, respectively (p = .74). CONCLUSION. Intussusception reduction may not require completion emergently (within 2 hours after diagnosis) but potentially may be safely performed on an urgent basis (within 8 hours). CLINICAL IMPACT. The findings have implications for determining the standard of care, including criteria for on-call activation of radiologic resources, in the management of pediatric intussusception.