Learning Curve for Point-of-Care Ultrasonography for Pediatric Skin and Soft Tissue Infections

Point-of-care ultrasonography (POCUS) for skin and soft tissue infections (SSTIs) has been integrated into routine clinical care in pediatric emergency medicine (PEM). Despite its widespread utilization, empirical data on skill development are required to inform standards of care. We sought to evaluate the accuracy of POCUS for the detection of SSTIs, and to estimate a learning curve as providers gained experience.

A database was created at a single urban pediatric emergency department (ED) for all POCUS studies performed for cellulitis and abscess among children from August 2009 to January 2020. Providers who completed at least 10 total studies were included. The accuracy of each study was asynchronously rated by 6 POCUS experts. We report each provider's learning curve. Within the provider, the studies were ordered temporally. Mixed-effect logistic regression was used to model study accuracy with study accuracy as the dependent variable, within-provider examination temporal order as a fixed effect, and random effects for provider-level intercept and longitudinal slope.

A total of 3408 ultrasounds by 87 providers were included. The median number of ultrasounds per provider was 32 (range: 10 to 184). Accuracy increased significantly with each additional scan [odds ratio: 1.02 (1.01, 1.03)]. Significant variability was found across provider-level intercepts ( P < 0.001) but not across slopes ( P = 0.215). To reach mean accuracy levels of 90% and 95%, averages of 29 and 80 scans were required, respectively.

POCUS accuracy for detecting pediatric SSTIs improved with experience, with a mean of 29 scans required to reach 90% accuracy.