Are Pre-anaesthetic Blood Tests in Dogs Really Necessary?

Are Pre-anaesthetic Blood Tests in Dogs Really Necessary?

Health & Safety

If your dog has to undergo some sort of surgery to treat a condition they are suffering from, the chances are the vet might suggest they have pre-anaesthetic blood tests to make sure it is safe for them to be put under during the procedure. So why is it that vets advise owners to have these tests done? Read on to find out why it is often safer to do so.

Why Pre-anaesthetic Blood Tests are Important

A vet would carry out a full examination of a dog and look at their health records before assessing whether they would be in good enough condition to undergo any sort of surgery. A dog's age also plays a key role in whether or not a vet thinks it would be safe for them to be given any sort of anaesthetic. However, pre-anaesthetic blood tests would pick up anything a vet might have missed in a full examination and would establish if there are any other health issues that need to be taken into account before a final decision is made.

Vets typically check a dog's heart and lungs during an examination which they do using a stethoscope. It allows them to detect any abnormalities, but should they detect anything, they would recommend having blood tests done and could even recommend having xrays or an ultrasound too. A healthy dog is less likely to need any blood tests before they undergo any sort of surgical procedure, but a dog that suffers from an ongoing or chronic health condition may need to have their bloods taken to establish whether it is safe for them to be put under.

Blood tests would show up any kidney or liver problems which would not be picked up during a general examination. If the red blood cell count is low, it could be an clear indication that a dog suffers from anaemia. They would also show up any inflammatory disease or infection which could be seen if the results show a high white blood cell count. Other things blood tests would show up include whether a dog is dehydrated which would show up if there is a higher than normal red blood cell count paired to higher protein levels.

Another advantage of having blood tests taken before a dog undergoes a surgical procedure is that once the results are received and all is okay, the procedure would be able to go ahead without any unnecessary delays. The vet would ask you not to feed your dog the day before they take blood because this offers the most accurate results and the blood is typically taken from a dog's jugular vein which is located in their neck.

The Benefits of Blood Testing

Research has established that although blood testing healthy dogs is not always necessary, when it comes to a dog that's unwell and/or suffering from a health issue, the benefits of carrying out the tests prior to them having surgery are tremendous. Not only would a vet be able to manage a dog's anaesthetic that much better during surgery, but they would also be able to make sure the treatment is as safe as possible for your dog to undergo. Older dogs and in particular dogs over the age of eight benefit more from having pre-anaesthetic blood tests than younger dogs.

Questions You Should Ask the Vet

If a vet recommends that your dog has pre-anaesthetic blood tests before they undergo any sort of surgery, there are several questions you might want to ask them which could include the following:

  • Why they think it necessary for the tests to be done?
  • How the test results will affect the fact your pet needs to be put under in order for a procedure to be carried out?
  • What alternatives would there be if the results come back and the vet would not be able to use anaesthetic on your dog?


It is always very worrying when a much loved dog has to be put under anaesthetic so they can be operated on. There is always a risk associated with any sort of sedation so when a vet recommends a dog to given pre-anaesthetic blood tests to make sure they are in the best of health before a procedure is carried out, it is always worthwhile asking why they think this is necessary. The chances are the vet may have picked up something when they examined your dog and would like to establish if they are suffering from any sort of health issue that would make giving them any sort of anaesthetic that much riskier. The blood tests would give the vet peace of mind and would help them manage your dog when they are sedated that much better.



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