A Randomized Comparative Study of the Effects of Pethidine and Midazolam on the Extent of Esophagogastric Junction Examination

[Abstract] Introduction: Sedative-analgesic agents are reported to reduce the pain and discomfort of esophagogastro-duodenoscopy (EGD), but the specific effects of these agents on examination of the esophagogastric junction (EGJ) are unknown. We conducted a prospective, randomized, double-blind clinical trial in which we compared the effects of midazolam and pethidine hydrochloride on EGJ examination during EGD. Methods: The 32 patients included in the study were chosen from among 80 patients scheduled to undergo EGD at our hospital between February 2016 and May 2018. Patients were randomly allocated to intravenous administration of midazolam (n=16) or pethidine (n=16). The midazolam was administered to patients at the same dose as during the previous examination, whereas the pethidine was administered at a dose of 35 mg. Perfect observation was defined as examination of the full circumferential extent of the EGJ. The primary study endpoint was the percentage of patients in whom perfect observation was achieved. Results: Perfect observation was achieved in six patients (37.5%) in the midazolam group and nine patients (56.3%) in the pethidine group (between-group difference: 18.8%, 95% confidence interval [CI]: -59.0% to 21.5%; P=0.29). The mean extent of EGJ examination was 65.0+-38.3% in the midazolam group and 78.6+-27.3% in the pethidine group (intergroup difference: -13.6%, 95% CI: -37.8% to 10.3%; P=0.25). The mean visual analog scale score for pain and discomfort during endoscopy was 0.75+-2.02 in the midazolam group and 2.25+-1.77 in the pethidine group, indicating significantly higher levels of discomfort in the pethidine group (intergroup difference: -1.50, 95% CI: -2.87 to -1.30; P=0.033). There was no between-group difference in the number of procedural accidents or degree of the endoscopists' satisfaction. Conclusion: Midazolam was superior to pethidine in relieving discomfort during EGD, but pethidine tended to be better than midazolam for observing the EGJ.