Preparing your pet for a general anaesthetic

The pre-anaesthetic period – what you need to know

preparing my pet for a general anesthetis

Putting your pet through a general anaesthetic can be a worrying time


Your pet will be admitted to the veterinary practice either by a vet or a veterinary nurse so they can ask questions to help in planning of the anaesthetic. It is important to know when your pet last ate and whether they are on any medications. We always ask if there are any other problems which you feel we need to be aware of.

Your veterinary practice will ask you to sign a form of consent and will explain any risks associated with the anaesthesia or sedation and the procedure to be performed.

Why is starvation necessary?

Before a sedation or anaesthetic you will be advised  to starve your pet overnight, exactly the same as you would be if you were having an anaesthetic. This is for several reasons, the main one being patient safety. Most anaesthetic drugs make people and animals either feel nauseous and sometimes they may cause vomiting. If this happens under anaesthesia then the normal protective reflexes in the throat and windpipe will be damped down by the anesthetic drugs. Therefore,  there is a high risk of food material entering the airways and causing pneumonia. It is also possible that acid reflux from the stomach  could damage the oesophagus (gullet or foodpipe). Both of these complications could have very serious and even grave consequences.  This is just one step to minimise any risks associated with a general anaesthetic. And so, if, despite your best efforts, your pet manages to eat before their anaesthetic then make sure you inform your vet upon admission. Don’t feel embarrassed or that you have failed in some way – tell them!

What if my pet is on medication?

Medications are very specific to each case and so it is important that your vet tells you which ones to give and which ones to withhold. For example heart medication should always be given at the appropriate interval. If your pet is on any medication and you aren’t sure what to do then do telephone the clinic and ask.


Following admission your pet will be assessed by a vet. This is a general health check, known as a clinical examination. The purpose of this examination is to check for new problems which may affect the anaesthetic. If your vet detects any abnormalities on examination he or she may recommend further tests prior to anaesthesia or sedation.

So does my pet need any pre-anaesthetic blood tests?

Not all patients need pre-anaesthetic blood tests to be performed. If your pet is fit and healthy and there are no problems detected on examination then there is no need for a blood test. If however your vet detects abnormalities during the examination or your pet is unwell then a pre-anaesthetic profile to check kidney and liver function for example may be recommended. From the recent scientific literature we know that 1 in 3 older dogs would benefit from a pre-anaesthetic blood screen – that’s dogs aged over 8 years old. Unfortunately this work has not been repeated in cats but it seems sensible to follow a similar approach to dogs.