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Case Description—2 horses were examined because of vascular masses involving the lower eyelid. Clinical Findings—Both horses had a unilateral, fluctuant mass involving the lower eyelid. For horse 1, the mass had been present since birth and had slowly increased in size over time. The mass also changed in size in response to various environmental stimuli, alterations in the position of the horse's head, and digital obstruction of superficial vessels adjacent to the mass. Horse 2 was brought to the hospital for euthanasia, and no historical or antemor-tem data were available. A combination of contrast angiography, Doppler ultrasonography, surgical exploration, and blood gas analysis (horse 1) and postmortem and histologic examination (horse 2) were used to determine that the masses consisted of non-neoplastic distended venous channels with anastomoses to the inferior lateral palpebral and angularis oculi veins (both horses) as well as the facial vein (horse 2). Histologic examination (horse 2) revealed large, endothelial cell-lined, blood-filled spaces within the deep dermis consistent with a distensible superficial venous orbital malformation. Treatment and Outcome—Horse 1 underwent surgical exploration and ligation of the vascular malformation. Six months after surgery, the mass was markedly reduced in size, and size of the mass was static regardless of head position or environmental stimuli. Clinical Relevance—Thorough preoperative planning with Doppler ultrasonography, contrast angiography, and blood gas analysis is recommended when attempting surgical correction of these malformations in horses. Surgical ligation can result in a successful cosmetic and functional outcome.

The objective of this study was to establish an ultrasound scoring system to assess the degree of fibrin tag and clot formation associated with jugular catheters in horses. A second objective was to test the hypothesis that, in healthy horses undergoing short-term anesthesia, polyurethane (PU) catheters have a different ultrasound score compared with polytetrafluoroethylene (Teflon) catheters. Twenty-three systemically healthy horses requiring anesthesia were randomly assigned PU or Teflon catheters. The mean catheter dwell time was 5 hours. Ultrasound was used to examine the jugular vein before catheter placement, before catheter removal (mean, 4 hours 45 minutes), and approximately 24 hours after catheter insertion (mean, 24 hours 42 minutes). The repeatability of the ultrasound scoring system was assessed by producing a series of randomly ordered selected still images for independent evaluation by four radiologists on two separate occasions. The interobserver and intraobserver repeatability was determined using a weighted kappa statistic, with substantial intraobserver repeatability mean κ .77 (range, .59–.91) and moderate interobserver repeatability mean κ .53 (range, .33–.67). The proportion of positive bacteriologic cultures in the polyurethane (PU) and Teflon groups was compared using Fisher's exact test, with no significant difference (P > .99) between the two groups. The distribution of the scores from the PU and Teflon groups was compared using the Mann-Whitney test, with no evidence of a difference between groups at the time of catheter removal (P = .23) and 24 hours after catheter insertion (P = .20). Further studies with a larger sample of systemically healthy horses are required to substantiate this preliminary finding.

SOUTH American camelids, such as llamas and alpacas, can be challenging to manage in the field. Not only are these animals unusual, they can also be very valuable. Although different anatomically, camelids can be considered simply as small ruminants, such as goats and sheep, as they experience similar problems under general anaesthesia (eg, regurgitation, profuse salivation and hypoventilation). This article provides some basic guidelines for field anaesthesia of camelids for routine procedures, such as castration, skin biopsies or abdominal ultrasound.

Laryngeal paralysis in horses has been reported after inhalational anesthesia and can result in significant morbidity/mortality. The cause of the condition is unclear. The objective of this study was to examine the effects of a standardized anesthetic protocol on laryngeal function and laryngeal/pharyngeal trauma in the peri-anesthetic period in a prospective study. A 30- to 60-second digitalized video clip of laryngeal movement from a standardized endoscopic view was recorded at five time points: before sedation, post-sedation, post-induction, immediately after recovery to standing, and at 24 hours after recovery. A standardized anesthetic regimen was used in all cases. Video clips were randomized and evaluated by two blinded assessors. Each assessor scored each clip for laryngeal function and trauma using previously validated scoring systems. Agreement between assessors was calculated using the mean of the five time-specific weighted kappa statistics. Post-anesthesia laryngeal function and trauma scores were compared with initial scores using the Wilcoxon signed rank test with Bonferroni adjustment. Spearman's rank coefficient was used to assess correlation between trauma and function scores and between anesthetic duration and laryngeal function and trauma scores. There was no significant effect of anesthesia on laryngeal function. Trauma scores were not significantly higher after tracheal intubation. The trauma scoring system requires further validation. There was no correlation between higher trauma scores and laryngeal function or duration and laryngeal function or trauma. Further work is required to evaluate other variables that may affect laryngeal function after anesthesia, using a larger number of horses with varying degrees of laryngeal dysfunction.

Removal of the wool-bearing skin around a young lamb’s rump (mulesing) provides long term health benefits for the animal, and the use of a sedative and analgesic agent such as xylazine may assist with pain relief to reduce discomfort and stress. Sensitive analytical methods are essential for monitoring pharmaceuticals and their metabolites in animals destined for human consumption. The following work reports a method that is 200 times more sensitive for xylazine detection than previously published methods, with lower limits of quantitation for xylazine and its primary metabolite in animals of 0.5 pg and 2 pg on-column, respectively. The use of a square wave solvent gradient immediately prior to analyte elution resulted in larger MS/MS peaks and a reduction in baseline noise, allowing reliable detection of lower analyte concentrations. The method uses as little as 1 mL of plasma which allows replication within a sample if required, and requires simple sample preparation, minimising the introduction of matrix components into the MS/MS.

Objective To evaluate the sedative, respiratory and cardiovascular effects of subcutaneously administered alfaxalone and butorphanol in a group of hyperthyroid cats. Design A prospective, single-centre observational study. Methods Client-owned hyperthyroid cats (n = 20) were examined and sedated with alfaxalone (3 mg/kg) and butorphanol (0.2 mg/kg) administered subcutaneously. Sedation scores, heart rate, respiratory rate and blood pressure were measured at 15-min intervals during the 45-min observation period and compared with pre-sedation values. At the end of 45 min, cats were assessed to be adequately sedated for oral administration of iodine-131 if there was minimal resistance and an intact gag reflex. Results The maximum median sedation score was reached 45 min after injection. The lowest mean heart and respiratory rates and blood pressure values occurred 30 min after injection. Significant decreases were noted in respiratory rates at all three time points (P < 0.001). Systolic, diastolic and mean blood pressure measurements were also significantly decreased at 15 and 30 min after injection (P < 0.05). Conclusion Subcutaneously administered alfaxalone and butorphanol can be used for sedation in cats undergoing procedures of short duration. Blood pressure should be monitored because of transient decreases observed in some cats. Further studies are required to determine whether the sedative, respiratory and cardiovascular effects are similar in euthyroid cats.

A horse which had had a caecal impaction for 10 days was treated by means of an ileocolostomy [corrected] but failed to respond satisfactorily. Before a second laparotomy was performed it was observed to have dislodged the extension set from a jugular catheter and air was heard being sucked into the vein. It became very agitated but was anaesthetised again and the impaction was removed through an incision in the apex of the colon [corrected] After recovering from the anaesthesia it developed severe signs of pruritus which subsided only after 12 hours. These signs were considered most likely to have resulted from a venous air embolism.