Pain management strategies for lumbar puncture in infants ≤6 months: A systematic review and meta-analysis

Lumbar puncture (LP) is a painful procedure performed in infants. Both national and international organizations recommend the use of local anesthetics for LP pain management. However, recommendations are not based on systematic review of the literature. The primary objective of this systematic review and meta-analysis was to synthesize the literature on local anesthetics and opioids for pain management in infants undergoing LP.

Databases were searched for randomized trials from inception to March 2024. The literature search was updated in June 2025 and no additional eligible articles were identified for inclusion. Title and abstract screening, full-text screening and data extraction were performed in duplicate. Risk of bias was assessed using Cochrane's risk of bias (RoB) 2.0 tool. The critically important outcome was pain measured using validated tools including unidimensional behaviour and multidimensional (comprising combinations of contextual, behavioural and/or physiological components) tools. Secondary outcomes included procedure success and adverse events. Pooled effect estimates were standardized mean difference (SMD) and relative risk (RR) with 95% confidence intervals (CI) using random effects models. A GRADE assessment of the overall certainty of the evidence for each outcome was completed.

Five studies with 292 infants were included. The interventions evaluated include local anesthetics (subcutaneous injection of lidocaine, needle-free jet injection of lidocaine using J-Tip and topical administration of lidocaine-prilocaine) and opioids (intravenous fentanyl). Local anesthetics were effective in reducing acute pain compared to placebo/control (SMD -0.70 [95% CI -0.89, -0.51]; I² = 0, n = 215). Fentanyl was effective in reducing acute pain compared to placebo (SMD -1.93 [95% CI -2.64, -1.21]). Across all comparisons, there was no difference in procedure success and number of attempts in studies including local anesthetics. No serious adverse events were attributed to local anesthetics or opioids. There was moderate to low certainty of evidence for all critical and important outcomes.

Both local anesthetics and opioids are effective in reducing pain associated with LP based on limited evidence and can be incorporated in clinical practice. Future studies should evaluate the effectiveness and safety of combined analgesia and alternative routes of administration for opioids.