Adverse events associated with bidirectional endoscopy with midazolam and pethidine

Same-day bidirectional endoscopy has been reported to reduce recovery time, and procedure-related cost. The safety of bidirectional endoscopy vs colonoscopy only, while using midazolam and pethidine, has never been evaluated. We reviewed 1,202 consecutive patients who underwent bidirectional endoscopy or colonoscopy only with administration of midazolam and pethidine in Toyoshima Ensdoscopy Clinic. We compared the clinical characteristics and adverse events associated with method of endoscopy (colonoscopy only vs bidirectional endoscopy). Furthermore, multivariate logistic regression analyses were conducted to study the role of age, sex, use of sedative, polypectomy, and bidirectional endoscopy in adverse events. In the bidirectional endoscopy group, the doses of pethidine and midazolam, and the incidence rates of hypoxia and posto-endoscopic nausea were significantly higher. On multivariate analysis, age (odds ratio = 1.061, p<0.001), use of pethidine (odds ratio = 4.311, p = 0.003), and bidirectional endoscopy (odds ratio = 3.658, p<0.001) were independently associated with hypoxia. On multivariate analysis, female sex (odds ratio = 10.25, p = 0.027) and bidirectional endoscopy (odds ratio = 6.051, p = 0.022) were independently associated with post-endoscopic nausea. In conclusion, bidirectional endoscopy could increase hypoxia in elderly patients using pethidine and post-endoscopic nausea in female patients.