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This study evaluated the antinociceptive and physiologic effects of xylazine (X) and detomidine (D) administered intrathecally (IT) at the lumbosacral space, before and after the injection of atipamezole (A) IV. The study was approved by the National Animal Protection Authorities. Five adult healthy female sheep were anaesthetized with propofol on four occasions to inject the following treatments IT: groups 1 and 2, 0.05 mg kg-1 X (2 mg mL-1 saline) IT; groups 3 and 4, 0.01 mg kg-1 D (0.5 mg mL-1 saline) IT (Waterman et al. 1988). Nociceptive threshold (TH) was tested by applying pulsed and stepwise enhanced direct current (Ludbrook et al. 1995) at one hind leg pastern and noting the current at the moment of foot lift. Maximum current applied was 40 mA. Baseline TH was measured twice before anaesthesia and every 10 minutes when the sheep regained consciousness. Atipamezole was given IV immediately after reaching maximum analgesic action of X and D as defined by two equal or decreasing TH values and measurements were continued for 90 minutes. The dose of A for groups 1 and 3 was 0.005 mg kg-1 (0.25 mg mL-1 saline) IV, and for groups 2 and 4 was 0.0025 mg kg-1 A (0.25 mg mL-1 saline) IV. Heart rate (HR), mean direct arterial pressure (MAP), PaO2 and PaCO2 were measured. The differences between measurements recorded before and after treatment were analysed using a paired t -test for the drug effects and a nonparametric Wilcoxon's rank sum test for the comparison between groups. A p -value < 0.05 was considered significant. All sheep were able to stand before A IV. Threshold baseline value was 4.5 ± 1.7 (mean ± SD) mA for all animals. Xylazine caused a significantly higher TH rise (35.2 ± 1.8 mA), faster onset (21.1 ± 16.0 minutes) and longer duration of the TH enhancement (104.1 ± 8.6 minutes) than D (TH: 16.3 ± 7.8 mA, onset: 49.5 ± 28.4 minutes, duration: 59.3 ± 27.3 minutes). A significant increase in PaCO2 was observed in the X and D treated animals, 0.39 ± 0.21 kPa (2.9 ± 1.6 mm Hg) and 0.39 ± 0.29 kPa (2.9 ± 2.2 mm Hg), respectively. Heart rate was significantly decreased by -21 ± 17 beats minute-1 for X animals and -13 ± 13 beats minute-1 for D. Mean arterial pressure (-9 ± 13 mm Hg for X and -1 ± 11 mm Hg for D animals) and PaO2 0.65 ± 1.32 kPa (4.9 ± 9.9 mm Hg) for X and 1.45 ± 4.19 kPa (10.9 ± 31.4 mm Hg) for D animals) did not change significantly. The nociceptive threshold was not affected by A in any group. Threshold values of all X treated animals before A was 39.3 ± 1.4 mA and after was 37.2 ± 6.3 (group 1) and 40 ± 0 (group 2). Threshold values of all D treated animals before A was 21.0 ± 8.3 and after was 19.4 ± 7.3 (group 3) and 24.8 ± 8.0 (group 4). At the dosages administered intrathecally in this study, X and to a lower degree D induce antinociception without major physiologic changes. Atipamezole up to 0.005 mg kg-1 IV does not affect the resulting antinociception as assessed by electrical stimulation. [ABSTRACT FROM AUTHOR]

Acquired tricuspid valve stenosis (TVS) is a rare complication of endocardial lead placement in humans that has not been described in the veterinary literature. We describe a 6.5-year-old Border terrier that was presented with right-sided congestive heart failure 5.5 years after placement of a transvenous pacemaker. Severe TVS was confirmed by cardiac ultrasonography and appeared to be secondary to excessive endocardial pacemaker lead within the right atrium. Repositioning of the lead proved impossible and subsequent postmortem examination demonstrated fusion of the tricuspid valve (TV) leaflets around the endocardial lead with associated narrowing of the tricuspid valve orifice. In addition, the loop of the endocardial lead was anchored by thick fibrous tissue to the right atrial wall. This case report suggests that if sufficient endocardial lead is left inside the heart, in dogs undergoing transvenous pacemaker therapy, the redundant lead can become adherent to the tricuspid valve apparatus and cause valvular stenosis.

Objective: To evaluate the analgesic and adverse side effects of intrathecal (IT) xylazine (XYL) and detomidine (DET) and the subsequent effects of two doses of intravenous (IV) atipamezole (ATI)., Study Design: Prospective, randomized, cross-over., Animals: Five adult healthy female sheep with mean body mass of 55 +/- 2.3 kg. Material and methods Each sheep underwent four treatments: 1) 50 microg kg(-1) XYL IT and 5 microg kg(-1) ATI IV, 2) 50 microg kg(-1) XYL IT and 2.5 microg kg(-1) ATI IV, 3) 10 microg kg(-1) DET IT and 5 microg kg(-1) ATI IV, 4) 10 microg kg(-1) DET IT and 2.5 microg kg(-1) ATI IV. Pain threshold (TH) was tested by applying pulsed and stepwise incremental direct current to the skin overlying the pastern. The current at the point of foot lift was recorded as the TH. Heart rate (HR), mean arterial pressure, arterial oxygen (PO(2)) and carbon dioxide (PCO(2)) tensions were monitored. Outcomes were derived as differences between baseline assessment and measurements after treatment. Two-way anova was used to analyse drug effects, treatment differences between groups were examined with an F-test or Wilcoxon's rank sum test in case of non-parametric data distribution. p was set at 0.05., Results: Both drugs increased the pain TH, caused small increases in PCO(2), and small decreases in HR, the latter was only significant for XYL recipients. Xylazine produced a significantly higher TH, more rapidly and for longer than DET. Atipamezole only significantly affected PaCO(2) in the XYL group 2. The pain TH was not affected in either group after IV ATI., Conclusions: At the doses used, IT XYL, and to a lesser extent DET, induced pastern analgesia. Atipamezole 5 microg kg(-1) IV antagonized some side effects without affecting analgesia., Clinical Relevance: Intrathecal XYL may be useful as an analgesic in sheep. Its safety is increased because IV ATI antagonizes side effects, but not analgesia.

Objective: To compare three opioid agonist drugs for perioperative analgesia in cats., Study Design: Prospective, blind, controlled, randomised trial., Animals: Ninety client-owned cats, weighing 3.1 (2.1-4.5) kg, aged 14.6 (6.0-84.0) months, were studied., Methods: Seventy-six cats, scheduled for ovariectomy, received either 0.6 mg kg(-1) racemic methadone, 0.3 mg kg(-1) levo-methadone, 0.05 mg kg(-1) dextromoramide or a saline placebo IM. Behaviour and body position were assessed and scored 20 minutes later by a single 'blinded' observer. Anaesthesia was induced with propofol and maintained with halothane. Heart rate (HR), respiratory rate (RR), Fe'CO2 and SpO2 were recorded during anaesthesia. Post-operatively, pain was categorised as absent, moderate or severe, on the basis of appearance, behaviour and response to palpation of the surgical wound (pain score). Appearance, pain scores and physiological variables were monitored every 30 minutes, for a duration of 4 hours. Differences between time-dependent continuous variables were analysed using mixed models for repeated measurements. Differences in categorical, time-dependent variables were analysed using chi2-tests. Significance was set at p < or = 0.05., Results: There were no significant changes in appearance after pre-anaesthetic medication. After surgery, there was no association between appearance and pain score with HR or RR. The assessment of pain depended on comparison with the placebo group, by comparing animals' reactions to wound palpation. Sixteen of the 18 cats in the placebo group and 14 of the 19 cats in the dextromoramide group showed signs of moderate-to-severe pain after surgery. In the levo-methadone group (n = 20), one animal showed pain after 60 minutes and two after 120 minutes. One cat in the racemic methadone group (n = 19) showed pain signs and behavioural changes at 60 minutes. Compared to the two methadone groups, 'rescue' analgesia was required more often in cats treated with dextromoramide or saline., Conclusion and Clinical Relevance: Dextromoramide (0.05 mg kg(-1)) was ineffective, while racemic methadone (0.6 mg kg(-1)) and levo-methadone (0.3 mg kg(-1)) provided effective analgesia in cats following ovariectomy, without behavioural, respiratory or cardiovascular side effects.

In today's society small rodents and rabbits are increasingly kept as pets. Anaesthesia is necessary for numerous reasons and proves to be a challenge for many veterinarians. Following surgical intervention analgesia is frequently neglected. This article reviews the preparation of small mammals for anaesthesia, the choice of anaesthetics and the possibilities of perioperative care including monitoring, complications, fluid therapy and analgesia.

Increasing is the number of Llamas (Llama glama) referred to veterinarians for diagnostic or therapeutic procedures which frequently require sedation or anaesthesia. Much of the knowledge concerning sedation and anaesthesia of domesticated ruminants and horses can be applied to sedate or anaesthetise a llama. A variety of considerations remain special for the llama. The article reviews all aspects of today's knowledge about sedation and anaesthesia of llamas.

The teeth of five adult captive brown bears (Ursus arctos ssp.) were examined and radiographed for occlusion, loss of teeth, dental plaque and calculus, and attrition under general anesthesia. Deposits of dental calculus were found in various locations with an overall prevalence of 8% to 15% of all tooth surfaces. In all five animals, severe enamel and dentinal attrition defects were observed in canine teeth with exposed pulp. Cage-chewing behavior is probably the main cause for the dental attrition. The composition of the food and feeding management are most likely responsible for the lack of natural cleaning and the resulting plaque and calculus formation. All affected canine teeth were treated with endodontic procedures using several materials and techniques, and evaluated one- to two-and-a-half years later by clinical examination, radiography, and scanning electron microscopy of silicone casts of the treated teeth. All coronal fillings were tight. The apices were not completely sealed in two teeth. We conclude that the use of adequate and specialized instrumentation and techniques for the treatment of these long, curved, large diameter root canals is more important than the particular endodontic and restorative materials used. The dental health status of zoo animals is an indicator of their general well-being. Preventive measures should be taken in their environment and management to minimize the risk of dental conditions.