Читать книгу Complications in Equine Surgery - Группа авторов - Страница 207

Alpha‐2 adrenergic agonists act centrally causing sedation, analgesia and muscle relaxation. These effects are dose related up to a maximal point, after which increasing the dose further only increases the degree of ataxia and lengthens the duration of the effects. Excessive ataxia due to excessive muscle relaxation may make it impossible to keep the horse standing. Excessive sedation and ataxia in the recovery period could result in injuries or an unsuccessful recovery.

The administration of xylazine, detomidine or romifidine to horses during the recovery period prolongs, but improves the recovery from isoflurane anesthesia, making it smoother, free of excitation and ataxia with minimal cardiopulmonary effects [14]. A study comparing the recovery quality when xylazine or romifidine were administered during the recovery period showed that a dose of 20 microg/kg of intravenous romifidine in healthy adult horses anesthetised with isoflurane for >1 hour, was associated with better recovery quality than a lower dose of romifidine or xylazine [15]. However, in a study of perioperative morbidity and mortality in horses, sedation with an alpha‐2 adrenergic agonist during recovery appeared to show some association with improved recovery scores but, in the final model, it was found to be less important than other factors [16].