Effect of caudal epidural xylazine on intraoperative distress and post-operative pain in Holstein heifers.

OBJECTIVE To compare the effects of caudal epidural xylazine versus saline on tolerance of paravertebral nerve block and flank surgery and on post-operative pain in heifers used for a veterinary student training laboratory. STUDY DESIGN Randomized controlled prospective study. ANIMALS Fourteen one-year-old, nongravid, healthy Holstein heifers, weighing 360 +/- 5 kg. METHODS Xylazine (0.05 mg kg(-1)) or 0.9% saline (5 mL) was injected using a caudal epidural technique to seven heifers undergoing a flank surgery. Nerve block of the right paravertebral fossa was performed using equal parts of lidocaine 2% and bupivacaine 0.5%. Heart and respiratory rates, rectal temperature, rumination frequency, and appetite were recorded before and at 4, 8, and 24 hours after surgery. Scores were recorded for: tolerance of local anesthesia injections (pre-operatively), sedation, ataxia and distress (intraoperatively, every 30 minutes), and pain (4, 8, and 24 hours post-operatively). RESULTS The animals reaction to local anesthetic injection was judged to be less in the xylazine group by both an experienced observer (p<0.001) and student surgeons (p<0.01). The xylazine group required less local anesthetic (82.9 +/- 13.8 mL) versus the saline group (108.4 +/- 19.6 mL, p=0.035). Intraoperatively, xylazine heifers were more sedated at all times (p-values from <0.001 to 0.017), were more ataxic for the first 1.5 hours (p-values from <0.001 to 0.026), and lower in distress at all times (p-values from <0.001 to 0.007). No difference in post-operative pain or physiologic variables was found, except immediately post-operatively, rectal temperature was higher in the xylazine group (39.5 +/- 0.3 degrees C) than in the saline group (38.6 +/- 0.2 degrees C, p<0.001). CONCLUSION AND CLINICAL RELEVANCE Compared with epidural saline, caudal epidural xylazine reduced distress of anesthetic injection and surgical manipulation in heifers and an improvement in animal well-being was apparent. This effect may have been as a result of sedation. Pre-operative epidural xylazine did not appear to improve post-surgical analgesia in our study.

[1]  Lesley J. Smith,et al.  A comparison of epidural buprenorphine with epidural morphine for postoperative analgesia following stifle surgery in dogs. , 2001, Veterinary anaesthesia and analgesia.

[2]  P. Pascoe,et al.  Perioperative pain management. , 2000, The Veterinary clinics of North America. Small animal practice.

[3]  R. Streeter,et al.  Pharmacologic effects of epidural versus intramuscular administration of detomidine in cattle. , 1999, American journal of veterinary research.

[4]  O. Vainio,et al.  Reversal of sedative and clinicophysiological effects of epidural xylazine and detomidine with atipamezole and yohimbine in buffaloes (Bubalus bubalis) , 1998, Veterinary Record.

[5]  M. Kietzmann,et al.  [Evaluation of the antinociceptive effect of systemic and epidurally applied xylazine in general anesthesia with isoflurane in dogs and the effect of atipamezole infection on postoperative analgesia]. , 1998, Berliner und Munchener tierarztliche Wochenschrift.

[6]  H. Buerkle,et al.  Pharmacological evidence for different alpha 2-adrenergic receptor sites mediating analgesia and sedation in the rat. , 1998, British journal of anaesthesia.

[7]  J. Steiss,et al.  Evaluation of analgesia induced by epidural administration of medetomidine to cows. , 1998, American journal of veterinary research.

[8]  T. Doherty,et al.  Comparison of halothane minimum alveolar concentration and minimum effective concentration in ponies. , 1997, Journal of veterinary pharmacology and therapeutics.

[9]  B. Rohrbach,et al.  Effect of high volume epidural morphine, ketamine and butorphanol on halothane minimum alveolar concentration in ponies. , 1997, Equine veterinary journal.

[10]  B. Rohrbach,et al.  The effect of epidural xylazine on halothane minimum alveolar concentration in ponies. , 1997, Journal of veterinary pharmacology and therapeutics.

[11]  M. Raffe.  Recent advances in our understanding of pain: how should they affect management? , 1997, Seminars in veterinary medicine and surgery.

[12]  S. Young,et al.  Modification of cardiopulmonary and intestinal motility effects of xylazine with glycopyrrolate in horses. , 1997, Canadian journal of veterinary research = Revue canadienne de recherche veterinaire.

[13]  S. Young,et al.  Cardiopulmonary and gastrointestinal motility effects of xylazine/ketamine-induced anesthesia in horses previously treated with glycopyrrolate. , 1996, American journal of veterinary research.

[14]  L. Urbán,et al.  New molecules in analgesia. , 1995, British journal of anaesthesia.

[15]  T. Duke,et al.  Xylazine epidural analgesia for cesarian section in cattle. , 1993, The Canadian veterinary journal = La revue veterinaire canadienne.

[16]  J. Thurmon,et al.  Duration of analgesia induced by epidurally administered morphine and medetomidine in dogs. , 1993, Journal of veterinary pharmacology and therapeutics.

[17]  S. Eades,et al.  Blockade of endotoxin-induced cecal hypoperfusion and ileus with an alpha 2 antagonist in horses. , 1993, American journal of veterinary research.

[18]  M. Ho,et al.  Reduction of isoflurane anesthetic requirement by medetomidine and its restoration by atipamezole in dogs. , 1993 .

[19]  A. J. Woods,et al.  Liveweight estimation of cattle by scale and by tape, a method comparison study , 1992, Tropical Animal Health and Production.

[20]  M. Maze,et al.  Alpha‐2 Adrenoceptor Agonists: Defining the Role in Clinical Anesthesia , 1991, Anesthesiology.

[21]  W. Muir,et al.  Caudal epidural analgesia induced by xylazine administration in cows. , 1990, American journal of veterinary research.

[22]  W. Muir,et al.  Influence of tolazoline on caudal epidural administration of xylazine in cattle. , 1990, American journal of veterinary research.

[23]  F. Bonnet,et al.  Clonidine-induced analgesia in postoperative patients: epidural versus intramuscular administration. , 1990, Anesthesiology.

[24]  J. Caron,et al.  Caudal epidural analgesia in cattle using xylazine. , 1989, Canadian journal of veterinary research = Revue canadienne de recherche veterinaire.

[25]  J. Caron,et al.  Epidural injection of xylazine for perineal analgesia in horses. , 1988, Journal of the American Veterinary Medical Association.

[26]  T. Roger,et al.  Colonic α2‐adrenoceptor‐mediated responses in the pony , 1987 .

[27]  A. Livingston,et al.  Autoradiographic localisation of α2 adrenoceptor binding sites in the spinal cord of the sheep , 1987 .

[28]  C. Allal,et al.  Depression of reticulo‐ruminal motor functions through the stimulation of 012‐adrenoceptors , 1987 .

[29]  R. Skarda.  Techniques of local analgesia in ruminants and swine. , 1986, The Veterinary clinics of North America. Food animal practice.

[30]  L. E. Davis,et al.  Halothane-sparing effect of xylazine in dogs and subsequent reversal with tolazoline. , 1984, Journal of veterinary pharmacology and therapeutics.

[31]  B. Morris,et al.  Effects of clonidine and xylazine on body temperature in the rat , 1984, British journal of pharmacology.

[32]  Kitzman Jv,et al.  Antagonism of xylazine sedation by 4-aminopyridine and yohimbine in cattle. , 1982 .

[33]  P. L. Young.  The effect of xylazine on the body temperature of cattle. , 1979, Australian Veterinary Journal.

[34]  R. Skarda.  Local and regional anesthesia in ruminants and swine. , 1996, The Veterinary clinics of North America. Food animal practice.

[35]  J. Castillo-olivares,et al.  Cardiopulmonary and analgesic effects of epidural lidocaine, alfentanil, and xylazine in pigs anesthetized with isoflurane. , 1995, Veterinary surgery : VS.

[36]  J. Rehage,et al.  [Experiences with the use of xylazine for sacral epidural anesthesia in cattle]. , 1994, DTW. Deutsche tierarztliche Wochenschrift.

[37]  M. Nussbaum,et al.  Epidural injection of xylazine: a new option for surgical analgesia of the bovine abdomen and udder. , 1990 .