Antagonistic effects of atipamezole, yohimbine and prazosin on medetomidine-induced diuresis in healthy cats

Effects of atipamezole dosage and timing of administration on recovery time and quality in cats following injectable anaesthesia incorporating ketamine

OBJECTIVES

The aim of this study was to establish the optimum dosage and timing of administration of atipamezole in cats undergoing general anaesthesia incorporating ketamine to provide the shortest recovery possible without unacceptably compromising recovery quality.

METHODS

In total, 128 healthy male cats (age range 2-108 months, weight range 0.56-5.22 kg) admitted for castration were randomly allocated to groups of 32. Anaesthesia was induced with 60 mg/m2 ketamine, 180 µg/m2 buprenorphine, 3 mg/m2 midazolam and 600 µg/m2 medetomidine intramuscularly (IM). Cats received 600 µg/m2 (groups 1ATI20 and 1ATI40) or 1.5 mg/m2 (groups 2.5ATI20 and 2.5ATI40) atipamezole IM either 20 (groups 1ATI20 and 2.5ATI20) or 40 mins (groups 1ATI40 and 2.5ATI40) after the 'quad'. Preparation time, surgical time, auricular temperature, times to sternal recumbency and first standing, and recovery quality score were recorded. Data were analysed using ANOVA, Kruskal-Wallis, Mann-Whitney U-tests and χ2 tests. Statistical significance was deemed to be P ⩽0.05.

RESULTS

Groups did not differ significantly in preparation or surgical time. Auricular temperature decreased significantly over time (P <0.01) but did not differ between atipamezole treatment groups. Time to sternal recumbency in group 2.5ATI20 (52.9 ± 22.3 mins) was faster than group 1ATI20 (65.7 ± 24.7 mins) (P ⩽0.05), but there were no significant differences between other groups. Time to first standing and recovery quality scores did not differ significantly between groups. Minimal adverse effects were seen.

CONCLUSIONS AND RELEVANCE

Atipamezole administration after 20 mins did not reduce recovery time but neither was recovery quality adversely affected compared with when it was administered after 40 mins, following datasheet recommendations with concurrent ketamine administration. The results of this study also suggest that an atipamezole:medetomidine dose ratio of 2.5:1 is more effective than 1:1 in reducing recovery time, regardless of timing of administration, although this only reached statistical significance for time to sternal recumbency when atipamezole was administered after 20 mins.

The Association of Shelter Veterinarians' 2016 Veterinary Medical Care Guidelines for Spay-Neuter Programs

As community efforts to reduce the overpopulation and euthanasia of unwanted and unowned cats and dogs have increased, many veterinarians have increasingly focused their clinical efforts on the provision of spay-neuter services. Because of the wide range of geographic and demographic needs, a wide variety of spay-neuter programs have been developed to increase delivery of services to targeted populations of animals, including stationary and mobile clinics, MASH-style operations, shelter services, community cat programs, and services provided through private practitioners. In an effort to promote consistent, high-quality care across the broad range of these programs, the Association of Shelter Veterinarians convened a task force of veterinarians to develop veterinary medical care guidelines for spay-neuter programs. These guidelines consist of recommendations for general patient care and clinical procedures, preoperative care, anesthetic management, surgical procedures, postoperative care, and operations management. They were based on current principles of anesthesiology, critical care medicine, infection control, and surgical practice, as determined from published evidence and expert opinion. They represent acceptable practices that are attainable in spay-neuter programs regardless of location, facility, or type of program. The Association of Shelter Veterinarians envisions that these guidelines will be used by the profession to maintain consistent veterinary medical care in all settings where spay-neuter services are provided and to promote these services as a means of reducing sheltering and euthanasia of cats and dogs.