Rabbits are the third most common species to be anaesthetised in companion animal practice. Rabbit deaths under anaesthetic are recorded between 0.73 – 1.39% (compared to o.o5% for dogs and 0.11% for cats). This equates to 1 in 72 anaesthetic deaths in rabbits compared to 1 in 700 deaths in dogs. 62% of rabbit deaths occur during the anaesthetic recovery phase (most within the first 3 hours). 40% of these are from cardiopulmonary related problems. Many rabbits suffer respiratory disease so careful pre-anaesthetic examination is essential. Rabbits are nose breathers meaning they can’t pant through their mouth. They also have a smaller lung capacity than many other species. Any respiratory compromise can have a serious impact on anaesthetic tolerance.
Rabbit anaesthesia is particularly challenging. The species is difficult to intubate and catheterise. There is considerable size variation between breeds and patients presented for anaesthesia are often in poor body condition. It is easy for practitioners to feel intimidated by rabbit anaesthesia. There is a greater degree of difficulty than cat and dog anaesthesia, increased risk of complications and many vets lack familiarity with the species.
Rabbits cannot vomit so don’t need to be starved prior to surgery. Many recommend removing food 1 – 2 hours prior to anaesthetic induction to reduce the amount of fluid within the stomach. Post anaesthetic ileus is quite common and poses a serious risk to rabbits during recovery. This can be brought on through pain, starvation, stress and dietary change.
Rabbits have a greater surface area to body mass which favours core heat loss during anaesthesia. Hypothermia can be prevented by using heat pads / heated gloves / insulated feet covers etc.
Fluids are very beneficial during anaesthesia. They are best administered through an ear vein. It is recommended local anaesthetic gel be placed over the vein 30 minutes prior to catheterisation.
There are a number of anaesthetic options that can be used in rabbits. These include:
- Premed sedation > iv induction > intubation with gas maintenance. If anticholinergic drugs are required, glycopyrrolate is more effective than atropine. Rabbits have the enzyme atropinesterase which breaks down atropine.
- Gas induction (using a mask or anaesthetic box), intubation & gas maintenance.
- Drug combinations given im, sc. If procedures are likely to be prolonged these animals can be intubated & maintained on gas.
Anaesthetic Pro includes a wide range of anaesthetic / pain management options available for use in rabbits.
Patient monitoring during anaesthesia is essential. Pulse oximetry is not as accurate in rabbits due to their rapid heart rate. Capnography is far more sensitive and provides more useful information on the patient’s physiological status.
Pain management post surgery is essential. Pain is a significant contributor to ileus. A number of drugs are effective analgesics in rabbits. These include opioids and NSAIDs.
Food should be offered as soon as the rabbit recovers anaesthesia.