A new VetCompass study, led by the Royal Veterinary College (RVC) and the University of Manchester, has quantified the real risk of anaesthesia in dogs. 

The paper, ‘Mortality Related to General Anaesthesia and Sedation in Dogs under UK Primary Veterinary Care’, published in Veterinary Anaesthesia and Analgesia1, used data from more than 150,000 dogs attending first opinion veterinary practices around the UK.

The study examined the overall risk of death for each dog which had at least one sedation and/or anaesthesia procedure over a set period of time.

The study also looked at anaesthesia related to neutering (spaying and castration) in dogs because these procedures are so common in the UK and anaesthetic risk can be a significant worry for owners.

The findings showed that currently there are 14 deaths in 10,000 dogs within two weeks of sedation/anaesthesia procedures carried out for any reason, of which 10 deaths per 10,000 are within 48 hours of these procedures.

For neutering surgeries in dogs, the risk is even smaller, with one death in 10,000 neuter procedures related to sedation and/or anaesthesia.

No association was seen between the age of puppies at the time of neutering and risk of death.

Factors associated with increased risk of sedation and anaesthetic-related death in this study included:

  • Older age
  • Poorer overall health
  • More urgent surgeries
  • Certain breeds such as Rottweilers and West Highland White Terriers compared with mixed breeds.

Certain breeds, such as Cocker Spaniels, were found to be at lower risk compared with mixed breeds.

The team also investigated whether flat-faced ‘brachycephalic’ breeds were associated with higher risk.

Surprisingly, longer-nosed ‘dolichocephalic’ breeds showed four times the odds of sedative/anaesthetic-related death compared with medium-length nose dogs, whereas no additional risk was seen in flat-faced breeds.

The authors of the paper say that overall, these results should provide some reassurance for the veterinary and dog-owning communities regarding the safety of neutering for young puppies, as well as the relative safety of sedatives and anaesthetics for more complex procedures.

For older dogs, those with poorer health or undergoing planned complex surgeries, the results emphasise the value of careful planning to manage the anaesthetic risks.

Urgent procedures, regardless of complexity, were shown to carry greater risk and therefore should be approached with high vigilance and caution. 

Dr Dan O’Neill, Associate Professor in Companion Animal Epidemiology at the RVC and co-author of the paper, said:

“This new VetCompass study can help owners deal with these fears by understanding the real anaesthetic risk is not that high: 14 deaths in every 10,000 dogs. Decision-making based on the known can now replace fear of the unknown.”

Full paper: https://doi.org/10.1016/j.vaa.2022.03.006 / https://www.sciencedirect.com/science/article/pii/S1467298722001015 


  1. SHOOP-WORRALL, S. J. W., O'NEILL, D. G., VISCASILLAS, J. & BRODBELT, D. C. 2022. Mortality related to General Anaesthesia and Sedation in Dogs under UK Primary Veterinary Care. Veterinary Anaesthesia and Analgesia.

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