Effects of anesthesia and analgosedation on gastrointestinal functioning

General anesthesia using volatile anesthetics leads to an almost complete inhibition of gastrointestinal motility which is rapidly reversible after removal of the anesthetic agent. When epidural or spinal anesthesia is used either for anesthesia or postoperative analgesia, gastrointestinal function is only slightly affected. In contrast to these rather clear effects of anesthetics, it is almost impossible to describe the impact of different analgosedation regimens on gastrointestinal function since no larger-scale clinical studies provide reliable data. It is clear that opioids and clonidine inhibit gastrointestinal motility through specific receptor sites. Benzodiazepines and propofol however, exert a general inhibiting effect due to their central effects, but they do not have any specific binding sites. No negative effects on gastrointestinal motility have been found for ketamine. Since all modern strategies for analgosedation do prefer combinations of different substances, one should be aware that these combinations effect the gastrointestinal function in the clinical setting.