INTRAVENOUS ANTISPASMODIC AND PATIENT-CONTROLLED ANALGESIA ARE OF BENEFIT FOR SCREENING FLEXIBLE SIGMOIDOSCOPY

The possible benefits of premedication with the antispasmodic hyoscine n-butyl bromide (hyoscine) and analgesia with inhaled nitrous oxide/o xygen mixture (nitrous oxide) were assessed in a double-blinded, place bo-controlled trial. Consecutive patients at normal risk for cancer un dergoing screening flexible sigmoidoscopy were randomly allocated to r eceive either (1) intravenous hyoscine 20 mg plus inhaled oxygen on de mand (n = 40), (2) sterile water injection plus inhaled nitrous oxide on demand (n = 48), or (3) sterile water injection plus inhaled oxygen on demand (n = 43). One recently trained primary care physician perfo rmed all procedures. Duration of the procedure, endoscopic findings, a nd depth of insertion were recorded. After the examination, screenees rated their degree of pain during the procedure using a visual analogu e scale. Depth of insertion did not differ between the three study gro ups, but the duration of the procedure was significantly less in the h yoscine group (median, 12.5 minutes) as compared with placebo (median, 18 minutes; p=.0008). Fifty-four percent of screenees chose to use th e on-demand gas. Pain scores were significantly lower in those individ uals who inhaled nitrous oxide as compared with placebo (p=.045). Prem edication with antispasmodic shortens total procedure time for flexibl e sigmoidoscopy by a moderately experienced endoscopist as compared wi th placebo. In this study, a significant number of screenees experienc ed discomfort during flexible sigmoidoscopy, which appeared to be redu ced by offering nitrous oxide inhalation.