As briefly touched on in Part 1, unfortunately our equine patients have a significantly higher risk of anaesthetic related death than other species. A large, multi-centred study of over 50,000 horse anaesthetics reported the overall rate as approx. 1 death per 100 anaesthetics, which is 100-1000 times more than the incidence of mortality associated with human anaesthesia. 

What are the main complications that occur?

• Cardiac arrest
• Fractures
• Myopathy (muscle damage) 
• Neuropathy (nerve damage) or spinal cord malacia
• Respiratory obstruction

What factors are associated with increased risk of complications?

• Length of procedure
• Age of the horse
• Late term pregnancy or lactation
• Weight
• Breed
• Lateral recumbency vs dorsal recumbency
• Severity of systemic illness ie endotoxaemia

What can be done to minimise the risk of complications?

There are a number of interventions that we are able to put in place to minimise anaesthetic complications. Ensuring that the surgery process is as short as possible is important, so accurate diagnosis of the problem before the horse is anaesthetised is imperative. Prompt identification of a colic that is likely to be surgical will reduce the severity of systemic compromise and therefore complications that are likely to occur. We routinely monitor a number of parameters in surgery, and our anaesthetists modify the anaesthesia as required to keep these in the appropriate range. Our recovery box has a rope system to provide assistance for those patients that require extra help standing up after anaesthesia