Abstract
The objective of the study was to determine the analgesic and systemic effects of subarachnoid administration of xylazine hydrochloride (XY), lidocaine hydrochloride (LI) and their combination (XYLI) in goats. Six healthy goats were used in a prospective randomised study. Three treatments were administered to each goat, with 1-week intervals between each treatment. Treatments consisted of 0.1 mg/kg xylazine, 2.5 mg/kg lidocaine and a combination of xylazine 0.05 (mg/kg) and lidocaine (1.25 mg/kg). Analgesia, ataxic, sedative, cardiovascular and respiratory effects, and rectal temperature were evaluated before (baseline) and at 5, 10, 15, and 30 min after subarachnoid injection, and then at 30-min intervals until loss of analgesia occurred. Lidocaine induced analgesia in 3.1 +/- 1 min (mean +/- SD), which lasted for 66 +/- 31 min. Heart and respiratory rates and blood pressure remained unchanged after lidocaine-induced analgesia. Xylazine induced analgesia in 9.5 +/- 2.6 min and xylazine-lidocaine in 3.2 +/- 1.2 min. Xylazine-lidocaine-induced analgesia lasted longer (178.3 +/- 37 min) than that induced by xylazine (88.3 +/- 15 min). The XYLI treatment induced prolonged motor blocking (115 min), more than the XY (80 min) and LI (90 min) treatments. Both xylazine and xylazine-lidocaine caused significant decreases in the heart and respiratory rates, but not in blood pressure. The combination of xylazine (0.05 mg/kg) and lidocaine (1.25 mg/kg) can be administered subarachnoidally (between last lumbar vertebra and 1st sacral vertebra) to produce prolonged (> 2.5 h) analgesia of the tail, perineum, hind limbs, flanks and caudodorsal rib areas in goats. Despite the prolonged analgesia, using this combination is desirable for relieving postoperative pain, but it may be a disadvantage due to a motor block when dealing with goats.
Highlights
Epidural or subarachnoid anaesthesia is considered to be advantageous for general anaesthesia in ruminants[25]
The analgesia test through a needle-prick was efficient and demonstrated which dermatomes were blocked after subarachnoid administration of the drugs
The xylazine-lidocaine combination produced a longer duration of complete analgesia (178.3 ± 37 min, mean ± SD) than xylazine (88.3 ± 15 min) or lidocaine (66 ± 31 min) alone in the region of the tail, perineum, hind limbs, flanks and dorsocaudal rib areas in goats
Summary
Epidural or subarachnoid anaesthesia is considered to be advantageous for general anaesthesia in ruminants[25]. Local anaesthetics have the potential to produce sensory, motor and sympathetic blocking by depressing axonal conduction of nerves. Onset of local anaesthetic effects is characterised by severe motor blocking in the hind limbs. 2 % lidocaine is used with this objective, but higher doses and concentrations induce lesions of the nervous tissues in a temporary or irreversible way[18,27]. The vasodilatation due to sympathetic blocking produced by subarachnoidally-injected local anaesthetics decreases the duration of anaesaDepartment of Veterinary Medicine – Surgery and Anesthesiology, Faculty of Veterinary Medicine, Federal University of Mato Grosso do Sul State, Brazil.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of the South African Veterinary Association
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.