THE EFFECTS OF MISMATCHED BLOOD TRANSFUSIONS
Although a transfusion with the wrong blood type won’t necessarily put a horse’s life in jeopardy, it’s still a good idea to seek a match, according to a study from the University of Pennsylvania’s New Bolton Center.
In people, there are eight different blood types, determined by group (A, B, O and AB) and antigens (known as the Rh factor). If a person receives blood with incompatible antigens, the resulting immune response can be deadly. For this reason, people are usually only given blood that matches their own type, and a test called cross-matching is done using the blood of both the donor and recipient prior to a transfusion.
By comparison, the procedure for administering blood transfusions to horses is
In a recent survey of veterinarians conducted in the United Kingdom, the horse’s response to pain-relieving medications was found to be the most commonly used diagnostic tool in cases of colic.
Researchers at the University of Nottingham sent questionnaires to 228 veterinarians asking about their first assessment of colic cases. The most frequent diagnostic test reported (87.2 percent) was “response to analgesia”— whether the horse’s condition improved after the administration of pain-relieving medication. Rectal examination was the second most cited measure (75.9 percent) and nasogastric tubing was the third (43.8 percent).
Three other tests—abdominal paracentesis (also known as “belly taps”), bloodwork and simpler because mismatched blood types do not usually lead to severe adverse reactions. “Horses do not generally have the naturally occurring alloantibodies [antibodies against different blood types] the way humans and cats do,” explains Rose Nolen-Walston, DVM. “The conventional wisdom was that they [only] needed to be cross-matched after the first transfusion because ultrasound—rounded out the top diagnostic choices.
Despite the popularity of certain diagnostic techniques, the researchers note that there was a wide variation in individual protocols: For each diagnostic test there was at least one veterinarian who indicated they use it in 100 percent of cases and at least one who indicated they never use it.
This, the researchers say, highlights “the need for further evidence to support decision-making” when diagnosing cases of colic.
Veterinary Record Open, it was assumed that they would [then] make antibodies against the proteins on the transfused blood.” There are eight major equine blood groups (A, C, D, K, P, Q, U and T) and nearly 30 equine antibody factors, making for a total of nearly 400,000 different combinations.
In a study to investigate the potential long-term impact of matching blood types for equine transfusions,