EFFECTS OF INTRAVENOUS KETAMINE ON GASTROINTESTINAL MOTILITY IN THE DOG

Objective: The purpose of this trial was to clarify the effects of int ravenous ketamine at anaesthetic and sub-anaesthetic dosages on gastro intestinal motility. Design: 20 beagles (group 1: 3 mg/ketamine/kg/h, n = 10; group 2: 30 mg ketamine/kg/h, n = 10), were investigated. Gast ric emptying (nuclide gastric emptying studies, liquid and semi-solid test meal), intestinal transit time (Hydrogen breath test with lactulo se) and intestinal motor function (perfusion manometry with 8 measurin g ports) were determined. As a control condition, the tests were perfo rmed on all dogs in the two groups during infusion of physiological sa line solution. Results: No significant differences in the motility pat terns were present between 3 mg ketamine/kg/h and the control conditio n. For group 2, a moderately significant (p < 0.05) increase in the in terdigestive motility index was observed for 30 mg ketamine/kg/h. Howe ver, this did not change the transit criteria. There was no significan t difference between ketamine and control condition tests with regard to cycle and phase lengths or the propagation rate of the activity fro nt. Conclusions: We conclude that ketamine provokes no basic changes i n gastrointestinal motility, at either sub-anaesthetic doses. It can t here fore be used to advantage in the continuous postoperative analges ia of intensive care patients, where repeated interventions are necess ary and no cardiopulmonary contraindications are present.