Pre anaesthetic blood testing

blood tubes

Modern veterinary anaesthetics have evolved immensely in the last 25 years or so and the safety margins are a lot higher for most procedures as a result. There is still, however, an element of risk in any anaesthetic and that risk is increased in certain scenarios e.g. very young, elderly or sick animals.

Alongside the evolution of anaesthetic agents has been the development of accurate and rapid blood tests that can be done in-house and help us to make better decisions around anaesthesia.

For a while we have been recommending pre-anaesthetic blood testing in elderly patients or other patients who might have a higher risk for anaesthesia. Even younger healthy animals can occasionally have underlying health issues that are not obvious so the “Gold Standard” is a blood test before every anaesthetic to reduce the risk. 
The blood test doesn’t replace a pre-anaesthetic check as each animal is given a thorough physical exam prior to being anesthetised.

The blood test looks at what the red and white blood cells are doing as well as other markers that show, for example, kidney or liver disease.  Both liver and kidney disease can dramatically affect how well a patient tolerates anaesthesia. 
Low red cells might indicate anaemia and high white cells might be an indicator of an infection going on. 

Sometimes an anaesthetic might be essential despite blood results not being 100% normal but with the information from blood tests we can reduce the risk by doing things like giving intravenous fluids or avoiding certain anaesthetics.
No two scenarios are the same- most of our job involves risk assessment on a case by case basis and as time goes by we can see the value of extending blood testing to elderly animals on a yearly basis to monitor essential system function in much the same way that our human colleagues do.

As always, if you have any questions around blood testing or anaesthetics, then a chat with any of our team members is a good starting point.

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