Point-of-Care Ultrasound Assessment of Bladder Fullness for Female Patients Awaiting Radiology-Performed Transabdominal Pelvic Ultrasound in a Pediatric Emergency Department: A Randomized Controlled Trial

Abstract

Study objective: Radiology-performed transabdominal pelvic ultrasound, used to evaluate female patients with suspected pelvic pathology in the pediatric emergency department (ED), is often delayed by the need to fill the bladder. We seek to determine whether point-of-care ultrasound assessment of bladder fullness can predict patient readiness for transabdominal pelvic ultrasound more quickly than patient sensation of bladder fullness.

Methods: We performed a randomized controlled trial of female patients aged 8 to 18 years who required transabdominal pelvic ultrasound in a pediatric ED. Patients were randomized to usual care or point-of-care ultrasound and then assessed every 30 minutes for subjective bladder fullness (0 to 4 ordinal scale) and qualitative bladder fullness by point-of-care ultrasound. Patients were sent for pelvic ultrasound when they reported 3 or 4 on the subjective fullness scale (usual care) or a large bladder was visualized (point-of-care ultrasound). Primary outcome was time from enrollment to completion of pelvic ultrasound. Secondary outcome was success rate of pelvic ultrasound on first attempt.

Results: One hundred twenty patients were randomized and 117 had complete outcomes (59 usual care, 58 point-of-care ultrasound). Kaplan-Meier curves differed between groups (P<.001). Median time to successful completion of pelvic ultrasound was 139 minutes (usual care) and 87.5 minutes (point-of-care ultrasound), with difference in medians 51.5 minutes (95% confidence interval [CI] 23.4 to 77.2 minutes). All point-of-care ultrasound patients had successful transabdominal pelvic ultrasound on the first attempt compared with 84.7% in the usual care group, with difference -15.3% (95% Bayesian credible interval -5.3% to -25.0%). Weighted κ for interrater agreement was 0.83 (95% CI 0.79 to 0.87).

Conclusion: Point-of-care ultrasound assessment of bladder fullness decreases time to transabdominal pelvic ultrasound and improves first-attempt success rate for female patients in the pediatric ED.

Trial registration: ClinicalTrials.gov NCT02923245.