Effects of alpha-2 adrenoceptor agonists during recovery from isoflurane anaesthesia in horses.
BACKGROUND
Recovery from inhalant anaesthesia in the horse is a critical and difficult period to manage; however, several factors could help to obtain a calm recovery period including choice of anaesthetic and analgesic procedure used and the conditions under which anaesthetic maintenance and recovery occur.


OBJECTIVE
The objective of this study was to evaluate and compare the quality of recovery in horses administered saline, xylazine, detomidine or romifidine during recovery from isoflurane anaesthesia.


METHODS
Six mature and healthy horses were premedicated with i.v. xylazine and butorphanol, and anaesthesia induced using ketamine. After 2 h of inhalant anaesthesia with isoflurane vaporised in oxygen, saline solution, xylazine (0.1 mg/kg bwt), detomidine (2 microg/kg bwt) or romifidine (8 pg/kg bwt) were administered. The quality of recovery of each horse and the degree of sedation and ataxia were evaluated. Cardiovascular and respiratory parameters were recorded, and arterial blood samples obtained and analysed for pH, PO2 and PCO2 during recovery.


RESULTS
Quality of recovery was better in groups treated with alpha-2 adrenergic receptors agonists, showing less ataxia. Degree of sedation was greater in the romifidine group.


CONCLUSIONS
We concluded that the administration of alpha-2 adrenoceptor agonists during recovery from isoflurane anaesthesia in horses prolonged and improved the quality of recovery without producing significant cardiorespiratory effects.


CONCLUSIONS
Administration of alpha-2 adrenoceptor agonists after inhalent anaesthesia could prevent complications during the recovery period.
Santos
M
M
Departamento de Patologia Animal II, Facultad de Veterinaria, Universidad Complutense de Madrid, Avda Puerta de Hierro, 28035 Madrid, Spain.
Fuente
M
M
Garcia-Iturralde
R
R
Herran
R
R
Lopez-Sanroman
J
J
Tendillo
F J
FJ
D058647:Adrenergic alpha-2 Receptor Agonists; D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000762:Anesthesia Recovery Period; D000768:Anesthesia, General / Q000662:veterinary; D018685:Anesthetics, Inhalation; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006736:Horses / Q000502:physiology*; D007093:Imidazoles / Q000008:administration & dosage; D007530:Isoflurane; D008297:Male; D018341:Receptors, Adrenergic, alpha-2 / Q000187:drug effects*; D012965:Sodium Chloride / Q000008:administration & dosage; D014991:Xylazine / Q000008:administration & dosage
D058647:Adrenergic alpha-2 Receptor Agonists; D000316:Adrenergic alpha-Agonists; D018685:Anesthetics, Inhalation; D007093:Imidazoles; D018341:Receptors, Adrenergic, alpha-2; D014991:Xylazine; D012965:Sodium Chloride; C041255:detomidine; C076257:romifidine; D007530:Isoflurane