Dissociative Anaesthesia During Field and Hospital Conditions for Castration of Colts

Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Acta veterinaria Scandinavica (Impact Factor: 1.38). 02/2006; 47(1):1-11. DOI: 10.1186/1751-0147-47-1
Source: PubMed


The principal aim of this study was to evaluate dissociative anaesthesia for castration of colts during field conditions. Three dissociative anaesthetic protocols were evaluated during castration of colts in an animal hospital. The protocol considered to be the most suitable was thereafter evaluated during castration of colts under field conditions. Respiratory and haemodynamic parameters and the response to surgery were determined during anaesthesia. All horses breathed air spontaneously during anaesthesia. Under hospital conditions 26 colts were randomised to receive one of three anaesthetic protocols: Romifidine and tiletamine-zolazepam (RZ); acepromazine, romifidine and tiletamine-zolazepam (ARZ); or acepromazine, romifidine, butorphanol and tiletamine-zolazepam (ARBZ). The surgeon was blinded to the anaesthetic protocol used and decided whether supplemental anaesthesia was needed to complete surgery. Under field conditions 31 colts were castrated during anaesthesia with the ARBZ protocol. All inductions, anaesthesia and recoveries were calm and without excitation under both hospital and field conditions. Surgery was performed within 5-20 minutes after the horses had assumed lateral recumbency during both hospital and field castrations. Under hospital conditions some horses needed supplemental anaesthesia with all three anaesthetic protocols to complete surgery. Interestingly, none of the horses castrated with protocol ARBZ under field conditions needed additional anaesthesia. Cardiorespiratory changes were within acceptable limits in these clinically healthy colts.

Download full-text


Available from: Gorel Christina Nyman
  • Source
    • "nificantly better pre - anesthetic sedation and quality of anesthesia by the addition of butorphanol to xylazine – tiletamine – zolazepam , detomidine – ketamine , romifidine – ketamine , and acepromazine – romifidine – tiletamine – zolazepam an - esthesia in horses , ponies , and mules ( Matthews et al . 1991 , 1992a , b ; Corletto et al . 2005 ; Marntell et al . 2006 ) . Furthermore , butorphanol infusion , 0 . 013 mg kg ) 1 hour ) 1 , decreased cortisol concen - trations and pain scores in horses in the first 24 hours after celiotomy ( Sellon et al . 2004 ) . The horses in this study represent a diverse group in terms of breed , age , sex , and weight . As a retrospective analysis , one significant"
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective To determine cardiovascular responses to administration of butorphanol in isoflurane-anesthetized horses. Study design Retrospective evaluation of anesthetic records. Animals Seventy-six horses anesthetized for a variety of clinical surgical procedures. Methods Anesthetic records of clinical equine patients anesthetized between January 1999 and December 2003 were searched. The records were reviewed for horses in which anesthesia was induced with ketamine and a benzodiazepine and maintained with isoflurane, and horses that received butorphanol intraoperatively. Exclusion criteria included horses in which the rate of infusion of an inotrope or end-tidal isoflurane concentration was changed 10 minutes before or after the butorphanol bolus. The horses were separated into two groups: group 1 horses received butorphanol at intervals as part of a balanced protocol, group 2 horses had ≥10% increase in heart rate (HR) or blood pressure within 10 minutes prior to butorphanol administration. Results Eighty-nine butorphanol administration events matched the criteria for inclusion, 49 in group 1 and 40 in group 2. There were no significant changes after butorphanol administration in systolic arterial pressure (SAP), mean arterial pressure (MAP), diastolic arterial pressure (DAP), and heart rate (HR) in group 1, or in end-tidal carbon dioxide concentration or hemoglobin oxygen saturation in either group. There were significant decreases in SAP (p < 0.0001), MAP (p < 0.0005), and DAP (p < 0.0008) after butorphanol administration in group 2. Conclusions and clinical relevance The results presented here confirm that butorphanol can be administered to horses during isoflurane anesthesia without adverse effects on HR and arterial blood pressure. The results imply that butorphanol can deepen the plane of anesthesia and obtund sympathetic stimulation from a surgical procedure.
    Full-text · Article · Dec 2007 · Veterinary Anaesthesia and Analgesia
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although there has been much theoretical research on vibration control of flexible structures, the important effects of actuators, in achieving the vibration control objectives, have generally been ignored. Structures consisting of interconnected flexible members where the control forces and moments are generated by electromechanical member dampers constitute an important class of controlled flexible structures. Mathematical models of such controlled systems are presented that include electromechanical interaction effects, effects arising from the transmission of the control forces and moments to the structure, as well as the dynamic effects of the flexible structure itself. A simple form of hierarchical control is presented, consisting of feedback of structural signals plus compensation of the member dampers. Conditions are indicated for which the controller is spatially decentralized. Conditions for stabilization of the closed loop are also presented.
    No preview · Conference Paper · Jan 1986
  • [Show abstract] [Hide abstract]
    ABSTRACT: Equine field practice commonly requires short- to medium-term anesthesia being induced in horses for either minor surgical or diagnostic procedures or for urgent medical care in emergency situations. Performing a general anesthetic in the field further increases the risk associated with equine anesthesia which already is high when compared with small animal or human anesthesia, even under best of hospital conditions. For this reason, cases for field anesthesia should be carefully selected and appropriate anesthesia protocols chosen by taking into account the peculiar setting of the location, the physical condition of the patient, and the specific circumstances of the surgical, diagnostic, or other procedures planned. This review provides an overview of the anesthetic techniques suitable for field anesthesia. First, the approach to the equine patient under field as compared with hospital conditions is addressed, followed by a detailed discussion of common field anesthetic protocols reported for use in adult horses and in foals. Finally, anesthetic protocols suitable for horses suffering injuries during or immediately after maximum exercise are addressed.
    No preview · Article · Jun 2007 · Clinical Techniques in Equine Practice
Show more