The effect of propofol on human gastric and colonic muscle contractions

Although propofol is widely used for sedation in the intensive care unit, t here are limited data on its effects on gastrointestinal motility. For that reason, we studied the in vitro effects of propofol on human gastric and c olonic smooth muscle. Grossly normal human gastric and colonic muscle strip s were mounted in an organ bath set-up for isometric contraction and stimul ated by acetylcholine (Ach), using a cumulative dose schedule in the absenc e or presence of different concentrations of propofol [1.7 x 10(-6) M (0.3 mu g/mL) to 4.4 x 10(-4) M (78 mu g/mL)]. Ach led to concentration-dependen t contraction of both gastric and colonic muscle strips, whereas propofol, at a concentration 6.7 x 10(-6) M (1.2 mu g/mL) and above, significantly de pressed Ach-induced contraction in a concentration-dependent manner for bot h smooth muscle preparations. In addition, propofol, at a concentration 2.7 X 10(-5)M (4.8 mu g/mL) and above, depressed spontaneous contractile activ ity of both smooth muscle preparations. Fat emulsion 10% (Intralipid(R)), t he solvent for propofol, had no effect on either the spontaneous activity o r the Ach-induced contraction of gastric and colonic smooth muscles. Implic ations: The success of enteral feeding requires a normal gastrointestinal m otility. We found that, at clinically relevant concentrations, propofol imp aired gastrointestinal contractile activity. Further investigations are req uired to determine the clinical significance of this change.