Lumbar puncture (LP) is one of the most common procedures performed in pediatric emergency departments but first-attempt success rates remain low and traumatic LP remains frequent. The aim of this study was to determine if ultrasound performed by emergency physicians improves the probability of first-attempt success for lumbar puncture in children.

This was a prospective randomized controlled trial conducted in two tertiary care, pediatric, university-affiliated emergency departments in 2017–2018. Eligible participants were children younger than 19 years old requiring an LP in the emergency department. They were randomized to either the standard landmark-based LP (SLP) or ultrasound-assisted LP (UALP) groups. Our primary outcome was the first-attempt LP success rate.

166 patients were enrolled, with 84 in the UALP and 82 in the SLP group. A total of 23 physicians performed ultrasounds in the study. The proportion of successful first-attempt LP was higher in the ultrasound group (60/84; 68%) than for the standard procedure (52/82; 60%), but this failed to reach statistical significance (difference: 8.1%; 95% CI: −6.4 to 22.2).

Our study does not support the routine use of ultrasound for performing lumbar puncture in children. Considering the minimal harm and ease of performance, ultrasound may be used as an adjunct and teaching tool in certain clinical situations.