Principles of rabbit anaesthesia for veterinary nurses

The following article looks at the basic principles of rabbit anaesthesia and how they can differ significantly from those of other species. Recognising and providing species-specific care is essential to ensuring patient safety and reducing the risk of a negative outcome. Before any animal is put under general anaesthetic it should be physically examined, and if necessary pre-anaesthetic tests carried out. This is becoming more common in rabbit medicine and as many rabbits may have underlying pathologies, such as subclinical Pasteurella multocida, it is imperative the rabbit has been examined and risk assessed before anaesthesia. The American Society of Anaesthesiologists (ASA) has a useful physical status scale which can be applied to any animal, categorising them into anaesthetic risk groups (Table 1).

Adapted from the American Society of Anesthesiologists, 2014

A study into the unexpected death of 160 rabbits undergoing general anaesthesia for ovariohysterectomy or castration revealed the incidence of anaesthetic-related deaths was 1.9% (Ishida et al, 2014). The study retrospectively looked at 160 rabbits all categorised according to the ASA scale and undergoing general anaesthesia. Two of the rabbits died within 1 hour of being administered a pre-medication and the other died 18 hours after surgery after suffering a cardiac arrest (Ishida et al, 2014). These rabbits were all categorised as risk level 3–4 as imaging and diagnostic testing revealed one was suffering from uterine disease, one had urinary calculus and the other had a gastrointestinal blockage; there was no information about the age of the animals. Although the sample number is small, this highlights the importance of assessing and evaluating the health status of the animal prior to anaesthesia and why anaesthetic protocols should be flexible to accommodate the patient.