Effect of midazolam on cardiopulmonary function during colonoscopy with conscious sedation

Background and AimConscious sedation of patients with midazolam reduces anxiety and pain and improves colonoscopy success rates. However, it may lead to adverse effects such as hypoxia and hypotension. The present study investigated the effects of midazolam on cardiopulmonary function during colonoscopy with conscious sedation. MethodsBetween January 2011 and September 2011, 126 consecutive patients undergoing colonoscopy were enrolled and divided into two groups: (i) sedation with midazolam (midazolam group, n=65); and (ii) no sedation (control group, n=61). Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and peripheral oxygen saturation (SpO(2)), were recorded before, during and after the endoscopic procedure. ResultsIn the midazolam group, SBP and DBP decreased more during colonoscopy than in the control group. However, the frequency of a significant change in SBP was similar in both groups. During colonoscopy, HR and SpO(2) decreased significantly in the midazolam group compared to those in the control group. SpO(2) levels returned to normal after the procedure. ConclusionsMidazolam induced decreases in SBP, DBP, HR and SpO(2) during colonoscopy. Clinically significant changes in SBP, HR, and SpO(2), however, were similar in the midazolam and control groups. These results suggest that midazolam has a tolerable effect on cardiopulmonary function and may be safely used during colonoscopy.