Pre-Anaesthetic Blood Tests

A pre-anaesthetic blood test is a test routinely performed prior to a procedure to ensure your pet is healthy enough to undergo a general anaesthetic or sedation. 

Why is this recommended?

While your pet might look fit and healthy on the outside, it’s difficult for us to determine whether their internal organs (especially the liver and kidneys) are working as well as they should be.

Pre-anaesthetic blood tests provide us with a detailed snapshot of your pet’s internal health, letting us assess the vital organs prior to an anaesthetic, and in turn allowing us to choose the safest anaesthetic drugs for your pet based on their results. In young healthy animals, pre-anaesthetic blood tests can prove dually beneficial as they provide a valuable baseline for the ongoing healthcare of your pet.

What are you checking?

The kidneys and liver are the two major organs involved in metabolizing and excreting anaesthetic drugs. We test the function of these by assessing specific enzymes that circulate in the blood. If these organs are not functioning optimally, we may see an elevation in one or more enzymes.
Pre-anaesthetic blood tests can detect even small abnormalities prior to surgery, thus allowing us to alter our anaesthetic protocol accordingly for your pet. A range of disease processes can be responsible for elevating enzymes, including infection, degeneration, congenital abnormalities, toxic damage or age-specific problems, and if found, elevations can then be investigated if required.

A pre-anaesthetic blood screen will also check your pet’s red and white blood cells and platelets. Platelets are cells in the bloodstream primarily involved in the clotting, and it’s very important we know your pet has an adequate number prior to surgery as there may be some bleeding (from skin and subcutaneous tissues) during surgery.

What does a pre-anaesthetic blood test involve?

A small amount of blood (approx. 2 ml) is collected from a vein – usually the jugular in the neck. We clip a small amount of hair (about 3cm x 3cm) to help visualise the vein and then clean away any dirt on the skin. The test is run in-house and we’ll contact you with the results prior to surgery if there are any abnormalities. If requested, we can also provide a copy of the results for your own records.  

Does my pet have to have a pre-anaesthetic blood test?

If your pet is 7 years or older and has not had a general blood test within the last 6-12 months, your pet must have the test to ensure their organs are healthy and able to metabolise the anaesthtic agent effectively.

For pets under 7 years of age, we leave this as an optional extra. However, we strongly recommend all animals undergoing a general anaesthetic have their blood tested.

Last updated on 6 October 2023
Tagged with: surgery