Submucosal Lidocaine Injection in Colonic Endoscopic Submucosal Dissection: A Single-Center, Double-Blind, Randomized Controlled Trial.

OBJECTIVES: Colonic spasm is one of the major technical challenges encountered during colonic endoscopic submucosal dissection (ESD), impairing visualization of the dissection plane and scope maneuverability. Submucosal lidocaine injection may help to overcome this challenge. This study aimed to evaluate the efficacy and safety of submucosal lidocaine injection during colonic ESD. METHODS: In this single-center, double-blind, randomized controlled trial, 110 patients scheduled for colonic ESD were randomly assigned to the lidocaine or control group. In the lidocaine group, 1% lidocaine with 0.6% sodium alginate was used for submucosal injection; in the control group, saline with 0.6% sodium alginate was used. The primary outcome was procedure time. Secondary outcomes included en bloc and R0 resection rates, incidence of severe spasms, number of antispasmodic administrations, operator satisfaction, and adverse events. RESULTS: The median procedure time was numerically shorter in the lidocaine group but did not reach statistical significance (67.5 vs. 78.0 min, p = 0.114). The en bloc and R0 resection rates were 100% and 84.6% in the lidocaine group, and 96.3% and 81.5% in the control group, respectively. Severe spasms occurred less frequently in the lidocaine group (34.6% vs. 74.1%), with fewer antispasmodic administrations (median, 1 vs. 2) and higher operator satisfaction scores (median, 4.0 vs. 2.5). No increase in adverse events was observed. CONCLUSIONS: Submucosal lidocaine injection did not significantly shorten procedure time, although it may serve as a useful adjunct for preventing colonic spasms during ESD. TRIAL REGISTRATION: The study was registered in the Japan Registry of Clinical Trials (jRCT1051230189).