Transfusion Medicine: Why do we need blood? 

It is becoming increasingly common for vets to use blood transfusions when treating specific blood diseases or traumas in small animal patients but how do we collect the blood and how is it given? We have created a series of blogs to give you a quick whistlestop tour of transfusion medicine.

Blood products are a precious resource in veterinary medicine and there are many ethical decisions to be made when considering their use. Blood banks can be found around the country, but stock depends on donors giving blood. In the UK, blood taken from cats under sedation or anaesthesia cannot be stored so it is rare for blood banks to have stores of cat blood as many cats require sedation for blood collection. Some practices have donor registers of animals that have been tested and can be called on to help in an emergency when blood products may be needed. Vets must consider the patient’s clinical condition and ability to recover after the transfusion as well as where to source the products. 

Conditions requiring blood products:

• Severe or acute anaemia
• Extensive blood loss following trauma such as a road traffic accident
• Plasma products may be used to treat clotting disorders due to inherited conditions, severe liver disease or rodenticides toxicity.

In extreme circumstances, cats can be given dog blood in a procedure called ‘xenotransfusion’. This can only happen once as the cat will generate antibodies to canine blood which will cause a large and potentially fatal reaction if a second transfusion is given. Xenotransfusion can be useful if feline blood is not available, and the patient needs fast stabilisation or to allow time for vets to obtain suitable feline blood. However, there are risks to this practice. The donated blood cells are destroyed by the body after a brief time, so the effects of the transfusion are not long lasting. Transfusion reactions are reported to be seen more often with xenotransfusion compared to cat-to-cat transfusions. 

A great resource is the Pet Blood Bank UK who have lots of resources and advice on your pets becoming blood donors. They run donation clinics around the country and are full of helpful and friendly advice. 

Next blog – Transfusion Medicine: Blood Donation