A Fixed Nitrous Oxide and Oxygen Mixture for Analgesia in Children With Leukemia With Lumbar Puncture-induced Pain: A Randomized, Double-blind Controlled Trial.

CONTEXT: Leukemia is the most common cancer in the childhood population. Lumbar puncture (LP) plays central role in the diagnosis and treatment process, but options for analgesia are limited. OBJECTIVES: The present study aims to evaluate the efficacy of a fixed N2O/O2 mixture to reduce pain in children with leukemia during LP as compared with placebo. METHODS: A double-blind, placebo-controlled, and randomized clinical trial involving children who needed LP for diagnosis or treatment was conducted in the pediatrics department of the General Hospital of Ningxia Medical University. Eligible patients were randomly assigned to inhale either a fixed N2O/O2 mixture or O2. The primary endpoint was the maximal pain level felt by the patient during the procedure measured using a numerical rating scale (0-10). RESULTS: One-hundred fourteen consecutive patients were enrolled in this study and randomized. Pain scores during the procedure showed a significant decrease in N2O/O2 mixture-treated patients to 1.05 ± 1.40 versus 8.00 ± 2.13 in controls (P < 0.01). No serious adverse effects were attributed to N2O/O2 mixture inhalation. Analysis of the satisfaction of patients receiving N2O/O2 mixture indicated that medical staff were satisfied with this treatment. CONCLUSIONS: This study demonstrated that self-administered fixed N2O/O2 is efficient to reduce pain related to LP in children with leukemia.