Background: The purpose of these studies was to determine the suitability of bisacodyl for stimulating high-amplitude-propagating contractions in pediatric studies of colonic manometry.
Methods: Water-perfused manometry catheters were inserted into the right colon of children referred for evaluations related to defecation disorders. Colonic motility was measured in a 3-hour test session: an hour fasting, an hour after a meal, and 30 minutes after administration of a provocative agent.
Results: Bisacodyl was superior to edrophonium as a stimulant for inducing high-amplitude-propagating contractions. Bisacodyl-induced high-amplitude-propagating contractions were similar in amplitude, duration, propagation velocity, and sites of origin and extinction to naturally occurring high-amplitude-propagating contractions. The effect of intrarectal bisacodyl was similar to that of intracecal bisacodyl, except for a delay of 10 minutes in onset. Bisacodyl induced high-amplitude-propagating contractions in all 28 children (22 with spontaneous high-amplitude-propagating contractions) without evidence of neuromuscular disease and in 2 of 9 children with a colonic neuromuscular disorder and no spontaneous high-amplitude-propagating contractions.
Conclusions: Bisacodyl-induced high-amplitude-propagating contractions were quantitatively and qualitatively similar to naturally occurring high-amplitude-propagating contractions. In selected cases, such as in children receiving total parenteral nutrition or restricted fluid intake, it may be possible to shorten diagnostic colonic manometry using bisacodyl rather than waiting for spontaneous high-amplitude-propagating contractions.