Prospective Investigation of a Novel Ultrasound-assisted Lumbar Puncture Technique on Infants in the Pediatric Emergency Department.

OBJECTIVE: The objective was to describe a novel ultrasound-assisted lumbar puncture (UALP) technique and to compare it to standard lumbar puncture (SLP) technique in infants. METHODS: A prospective, randomized, controlled study in infants 60 days old and younger undergoing a lumbar puncture (LP) in a pediatric emergency department. Patients with a spinal anomaly or ventriculoperitoneal shunt were excluded. Eligible infants were randomized to UALP or SLP. A spinal sonogram was performed on all patients by an investigator not involved in performing the LP. Spinal landmarks and maximum safe depth were identified for the UALP providers. Providers in the SLP group were blinded to sonographic measurements. A successful LP was defined as the collection of cerebrospinal fluid (CSF) with a red blood cell count of less than 10,000 cells/mm3 . Statistical analysis included chi-square, Mann-Whitney U-test, and number needed to treat (NNT). RESULTS: Forty-three patients were enrolled, 21 in the UALP group and 22 in the SLP group. Prematurity, weight, length, provider experience, anesthesia use, stylet technique, and number of attempts were similar between groups. The median age in the UALP group was 38 days (interquartile range [IQR] = 33 days) versus 45 days (IQR = 19 days) in the SLP group (p = 0.02). CSF was obtained in all UALP subjects (100%) versus in 18 of 22 (82%) in the SLP group (p = 0.04); 20 (95%) UALP subjects versus 15 (68%) SLP subjects met our definition of success (p = 0.023). The odds ratio of successful LP using UALP technique was 9.33 (95% confidence interval [CI] = 1.034 to 84.026) and the NNT was 3.7 (95% CI = 2.02 to 24.18). CONCLUSION: The UALP technique increases the rate of a successful LP in infants compared to standard technique.