Real-time Ultrasound-guided Lumbar Puncture: A Comparison of Two Techniques Using Simulation

The current literature on the use of real-time ultrasound-guidance for lumbar punctures (LP) is limited. Two techniques have been described: the paramedian sagittal oblique (PSO); and the transverse interlaminar (TL) approach. Our objectives in this study were to compare the procedure outcomes between these two techniques and assess the ability of emergency physicians to perform ultrasound-guided LPs.

This was a prospective study whose participants included emergency physicians. Participants were randomized into either Group P (PSO technique) or Group T (TL technique). After a didactic session, participants then performed an ultrasound-guided LP on a training manikin, during which we collected procedure data. A survey was administered after completion of the procedure.

A total of 31 participants were included, 16 in Group P and 15 in Group T. Most participants (90.3%) successfully performed the procedure, without a statistical difference between Group P and Group T (15/16 vs 13/15, P = 0.95). Group T required a longer average time to complete the procedure (176.7 ± 140.4 seconds [s] vs 311.2 ± 202.3 s, P = 0.04). There was no statistically significant difference between Group P and Group T with regard to average time needed to obtain the required ultrasound view (18.3 ± 14.6 s vs 35.1 ± 32.9 s, P = 0.09); number of needle redirections; total number of needle passes; first puncture success; number of participants who advanced the needle without visualization of the tip (13/16 vs 14/15, P = 0.64); penetration of the anterior dura; and needle contact with bone. The Likert-style questionnaire responses (reported on a 1-10 scale) revealed no difference between Group P and Group T as to perceived difficulty of finding the required ultrasound view (3 [interquartile range (IQR) 2-5) vs 5 (IQR 3-6.5), P = 0.10), perceived difficulty of needle tracking, or rating of the needle view when entering the intrathecal space. However, Group T reported a higher overall perceived level of difficulty (4 [IQR 3-5] vs 6 (IQR 5.5-7.5), P= 0.01).

This study suggests emergency physicians can be trained to use ultrasound-guidance for lumbar puncture in the simulation setting without significantly prohibitive training. Both techniques were performed with high success rates. There may be a preference for implementing the paramedian sagittal oblique approach over the transverse interlaminar.