Effects of postoperative ketamine infusion on pain control and feeding behaviour in bitches undergoing mastectomy.
OBJECTIVE
To determine if ketamine administered to bitches at the end of a mastectomy, followed by a six-hour constant rate infusion (CRI), improved postoperative opioid analgesia and feeding behaviour.


METHODS
The bitches were randomised into three groups: the placebo group received 0.09 ml/kg isotonic saline intravenously followed by a six-hour CRI of 0.5 ml/kg/hour, the low-dose ketamine received 150 microg/kg ketamine intravenously followed by a six-hour CRI of 2 microg/kg/minute and the high-dose ketamine group received 700 microg/kg ketamine intravenously followed by a six-hour CRI of 10 microg/kg/minute. Any additional opioids given were recorded at the time of extubation and at intervals after extubation. Food intake was evaluated eight (T8) and 20 (T20) hours after extubation by measuring the per cent coverage of basal energy requirements (BER).


RESULTS
No significant difference was observed for opioid requirements between the three groups. The mean percentages of BER coverage did not differ significantly at T8 but the difference between the high-dose and low-dose ketamine groups (P=0.014), and the high-dose ketamine and placebo groups (P=0.038) was significant at T20.


CONCLUSIONS
This study demonstrated that 700 microg/kg ketamine given intravenously postoperatively followed by a six-hour ketamine CRI of 10 microg/kg/minute improved patient feeding behaviour.
Sarrau
S
S
National Veterinary School of Toulouse, Anaesthesia and Critical Care Unit, 23, Chemin des Capelles, 31076 Toulouse Cedex, France.
Jourdan
J
J
Dupuis-Soyris
F
F
Verwaerde
P
P
D000778:Anesthetics, Dissociative / Q000008:administration & dosage / Q000627:therapeutic use*; D000818:Animals; D004283:Dog Diseases / Q000473:pathology / Q000601:surgery*; D004285:Dogs; D005247:Feeding Behavior; D005260:Female; D007262:Infusions, Intravenous / Q000662:veterinary; D007649:Ketamine / Q000008:administration & dosage / Q000627:therapeutic use*; D015674:Mammary Neoplasms, Animal / Q000473:pathology / Q000601:surgery; D008408:Mastectomy / Q000662:veterinary*; D010147:Pain Measurement / Q000662:veterinary; D010149:Postoperative Pain / Q000517:prevention & control / Q000662:veterinary*; D016896:Treatment Outcome
D000778:Anesthetics, Dissociative; D007649:Ketamine