Introduction

Spay-neuter programs are becoming more popular as a mandatory component to decrease overpopulation and euthanasia of stray dogs and cats.^1,2 These programs can have a great impact on animal welfare; the goal is to protect the animal's primary needs. In this case, stress, fear and anxiety are reduced by using appropriate transportation, environment and handling. Physical suffering should be avoided by maintaining appropriate homeostasis, normothermia and by providing analgesia.

Trap-neuter-vaccinate-return programs maintain the cat as a valuable asset in rodent control and can be an important alternative to massive euthanasia. These programs are only effective if catching is performed without injuries to the animals.

Preparation

Safety is the most important priority during transportation of a patient. There should be always appropriate ventilation, identification of patients with medical record, means of monitoring during transfer and avoidance of excessive confinement. Patient selection should be determined in advance. For example, the program should have an "age" policy (minimal age for neutering), number of patients/day according to personnel, facilities and equipment, and health status. The risks and benefits of neutering diseased, pregnant and animals during estrus should be outweighed. Fasting should also be planned depending on the age. Food but not water is commonly withdrawn between 6–8 hours in adults, approximately 4 hours for juvenile and less than 2–3 hours for pediatric patients. Physical examination is mandatory unless patients are fractious.

Housing

A disinfection protocol should always be in place for housing and equipment. Pediatric patients may be housed together and escapes should be prevented.

Anesthesia and Analgesia

Adequate anesthesia and pain management are crucial parts of a successful canine and feline spay-neuter programs.³ These environments present a challenge for the veterinarian in regards to geography and limited personnel and drug/equipment availability. Both anesthetic and analgesic protocols will have to be tailored to each specific situation.³ Balanced anesthesia and multimodal analgesia provide pain relief, muscle relaxation, unconsciousness and immobility. Protocols will vary with geographic location, equipment availability, facilities and familiarity of personnel with anesthetic drugs. The most ideal protocol should be effective, reversible, economically viable, provide pain relief, avoid adverse-effects, species-specific, and have a small injection volume.^4-8 Hypothermia should be prevented with the avoidance of conductive heat loss, excessive hair removal or the use of excessive alcohol scrubbing solutions and limiting body cavity exposure, among other strategies. Ideally, there should be a source of ventilation and oxygenation. Monitoring can be performed by trained observers and "hands-on" monitoring. Standard kits and drug charts are used for the anesthetic/analgesic protocols and for emergencies.

This session will provide guidelines for: perioperative care (physical examination, patient housing, infectious control, minimal equipment), anesthetic-analgesic management (monitoring, drug protocols, fluid therapy, emergency setting, recovery) and general considerations based on current evidence and expert opinion. Particular anesthetic and analgesic protocols will be presented. The ultimate goal is to provide humane methods for neutering large number of cats and dogs and an alternative to massive euthanasia due to overpopulation.

References

1.  Sparkes AH, Bessant C, Cope K, et al. ISFM Guidelines on population management and welfare of unowned domestic cats (Felis catus). J Feline Med Surg. 2013;15:811–817.

2.  Patronek GJ, Glickman LT, Beck AM, McCabe GP, Ecker C. Risk factors for relinquishment of dogs to an animal shelter. J Am Vet Med Assoc. 1996;209:572–581.

3.  Looney AL, Bohling MW, Bushby PA, et al. The association of shelter veterinarians veterinary medical care guidelines for spay-neuter programs. J Am Vet Med Assoc. 2008;233:74–86.

4.  Williams LS, Levy JK, Robertson SA, Cistola AM, Centonze LA. Use of the anesthetic combination of tiletamine, zolazepam, ketamine, and xylazine for neutering feral cats. J Am Vet Med Assoc. 2002;220:1491–1495.

5.  Cistola AM, Golder FJ, Centonze LA, McKay LW, Levy JK. Anesthetic and physiologic effects of tiletamine, zolazepam, ketamine, and xylazine combination (TKX) in feral cats undergoing surgical sterilization. J Feline Med Surg. 2004;6:297–303.

6.  Ko JC, Abbo LA, Weil AB, Johnson BM, Payton M. A comparison of anesthetic and cardiorespiratory effects of tiletamine-zolazepam-butorphanol and tiletamine-zolazepam-butorphanol-medetomidine in cats. Vet Ther. 2007;8:164–176.

7.  Ko JC, Berman AG. Anesthesia in shelter medicine. Top Companion Anim Med. 2010;25:92–97.

8.  Faggella AM, Aronsohn MG. Anesthetic techniques for neutering 6- to 14-week-old kittens. J Am Vet Med Assoc. 1993;202:56–62.