Dexmedetomidine for conscious sedation with colorectal endoscopic submucosal dissection: a prospective double-blind randomized controlled study

OBJECTIVE: Conscious sedation for colorectal endoscopic submucosal dissection (ESD) has not been standardized, and there are no studies of sedation for colorectal ESD. METHODS: We conducted a prospective double-blind randomized controlled trial to clarify the usefulness of DEX during colorectal ESD. In total 80 patients with colorectal ESD from April 2016 to May 2017 were assigned to the placebo group or the DEX group (40 cases each). The primary outcome was patient satisfaction (visual analogue scale: VAS). Secondary outcomes were evaluated for 13 factors, including patient pain level (VAS), endoscopist satisfaction (VAS), objective patient pain level viewed from the endoscopist’s perspective (VAS), rate of patient response, rate of side effects, etc., from the patient’s and endoscopist’s perspectives. RESULTS: Patient satisfaction was 8.4 and 9.1 (P = 0.018) in the placebo group and the DEX group, respectively. Secondary outcomes of patient pain level, endoscopist satisfaction, objective patient pain level from the endoscopist’s perspective for the placebo and DEX groups were 1.2 and 0.4 (P = 0.045), 8.2 and 9.3 (P < 0.001), and 1.2 and 0.5 (P = 0.002), respectively. All of these were significantly positive results (more comfortable and less pain) in the DEX group. The rate of a patient response was 100% in all cases. The side effects (hypoxia/bradycardia/hypotension) were 0%/0%/0% and 7.5%/7.5%/5% (P = 0.030). However, these rates were less than the reported side effect occurrence rate, and no additional medication was needed. CONCLUSION: DEX enables conscious sedation, and is useful not only for patient and endoscopist satisfaction but also for pain relief. DEX is an effective sedation method for colorectal ESD.