Effects of a single dose of ketamine on duodenal motility activity in pigs.

In order to investigate the effects of a single dose of ketamine on duodenal motility, the present study focused on the electric impedance technique. Five pigs (32 to 40 kg, CVC group) were instrumented with a central venous catheter 1 d before measurements. The next day, general anesthesia was started and maintained via central venous catheter by propofol and fentanyl. In contrast, the pigs of the KETA group (n = 5) received ketamine intramuscularly prior to the induction of anesthesia by the injection of propofol-fentanyl via an ear vein. An intraluminal impedance catheter was manually introduced into the proximal duodenum. Measurements were recorded for 4 h. The KETA group showed a median duration of phase II that was shortened by 35%, while phase I was prolonged by 73% (P < 0.05). In conclusion, when gastrointestinal motility has to be investigated, the effects of a single dose of ketamine, even for premedication, should be taken into consideration.