Comparison of four drug combinations for total intravenous anesthesia of horses undergoing surgical removal of an abdominal testis.
OBJECTIVE
To evaluate anesthetic effects of 4 drug combinations used for total intravenous anesthesia of horses undergoing surgical removal of an abdominal testis.


METHODS
Clinical trial.


METHODS
32 healthy cryptorchid horses.


METHODS
Horses were sedated with xylazine and butorphanol and were randomly assigned to 1 of 4 groups: induction of anesthesia with ketamine and diazepam and maintenance with bolus administration of ketamine and xylazine (KD/KX); induction and maintenance of anesthesia with bolus administration of tiletamine-zolazepam, ketamine, and detomidine (TKD); induction and maintenance of anesthesia with continuous infusion of xylazine, guaifenesin, and ketamine; and induction and maintenance of anesthesia with continuous infusion of guaifenesin and thiopental. Horses that moved 3 consecutive times in response to surgical stimulation or for which surgery time was > 60 minutes were administered an inhalant anesthetic, and data from these horses were excluded from analysis.


RESULTS
Quality of induction was not significantly different among groups. Muscle relaxation and analgesia scores were lowest for horses given KD/KX, but significant differences among groups were not detected. Horses anesthetized with TKD had a significantly greater number of attempts to stand, compared with the other groups, and mean quality of recovery from anesthesia for horses in the TKD group was significantly worse than for the other groups. Anesthesia, surgery, and recovery times were not significantly different among groups.


CONCLUSIONS
Results suggest that all 4 drug combinations can be used to induce short-term anesthesia for abdominal cryptorchidectomy in horses. However, horses receiving TKD had a poorer recovery from anesthesia, often requiring assistance to stand.
Muir
W W
WW
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus 43210, USA.
Lerche
P
P
Robertson
J T
JT
Hubbell
J A
JA
Beard
W
W
Miller
T
T
Badgley
B
B
Bothwell
V
V
D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage; D000698:Analgesia / Q000662:veterinary; D000700:Analgesics / Q000008:administration & dosage; D000771:Anesthesia, Intravenous / Q000379:methods / Q000662:veterinary*; D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative / Q000008:administration & dosage; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D000818:Animals; D014151:Anti-Anxiety Agents / Q000008:administration & dosage; D001794:Blood Pressure; D003456:Cryptorchidism / Q000601:surgery / Q000662:veterinary*; D003975:Diazepam / Q000008:administration & dosage; D006140:Guaifenesin / Q000008:administration & dosage; D006339:Heart Rate; D006734:Horse Diseases / Q000601:surgery*; D006736:Horses; D007093:Imidazoles / Q000008:administration & dosage; D007649:Ketamine / Q000008:administration & dosage; D008297:Male; D013874:Thiopental / Q000008:administration & dosage; D013992:Tiletamine / Q000008:administration & dosage; D014991:Xylazine / Q000008:administration & dosage; D015041:Zolazepam / Q000008:administration & dosage
D000316:Adrenergic alpha-Agonists; D000700:Analgesics; D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D018686:Anesthetics, Intravenous; D014151:Anti-Anxiety Agents; D007093:Imidazoles; D014991:Xylazine; D013992:Tiletamine; D006140:Guaifenesin; D007649:Ketamine; C041255:detomidine; D015041:Zolazepam; D013874:Thiopental; D003975:Diazepam