L32b: transfusions in large animals

why would a large animal need a whole blood transfusion?

1. whole blood loss

2. anemia

3. loss of clotting factors

4. inadequate production

5. failure passive transfer in calves

why would large animals need a plasma transfusion?

1. failure of passive transfer in horses

2. protein loss

why do we tend to just give whole blood in cows?

cow blood is harder to separate

what can cause acute whole blood loss in cattle?

1. rupture

2. trauma

what can cause chronic whole blood loss in cattle?

1. ulcer

2. parasites

what does chronic whole blood loss in cattle lead to over time?

non-regenerative anemia

which external blood vessel can lead to acute blood loss in cows?

mammary vein

which internal issues can lead to acute blood loss in cows?

1. abomasal ulcer

2. middle uterine artery

3. ruptured organ

4. caudal vena cava syndrome

type 1 abomasal ulcer in cows

 a simple loss of the abomasal lining (epithelium) without significant bleeding or penetration through

the muscular layer → non-perforated and minimal bleeding

type 2 abomasal ulcer in cows

A non-perforating ulcer that erodes a major blood vessel, causing significant bleeding into the

abomasum or fece → hemorrhagic, non-perforating

type 3 abomasal ulcer in cows

A perforated ulcer that allows abomasal contents to leak out and cause inflammation in a localized

area of the peritoneal cavity → localized periotonitis

type 4 abomasal ulcer in cows

A perforating ulcer with a rapid spread of abdominal contents throughout the entire peritoneal cavity,

leading to acute and generalized peritonitis → diffuse peritonitis

type 5 abomasal ulcer in cows

an additional stage for a perforated ulcer that involves inflammation of the omental bursa

what signs may we see in a cow with an abomasal ulcer type 3-5?

1. decreased milk yield

2. decreased fecal output

3. decreased appetite

4. increased rumen size → distended abdomen

MCQ: What type of abomasal ulcer may require a blood transfusion as part of the treatment plan?

type 2

MCQ: A 5yo Angus bull is examined on the farm due to a bloody nose of unknown

duration. On examination, the bull is lethargic, sclera are pale, and he is about 7%

dehydrated. T = 102F (38.9C), HR 100 bpm, RR 48 br/min, 1 RC/2 min.

Frank blood is observed dribbling out of both nostrils. Where is this blood originating from?

lungs (sinus would be only one nostril not two)

what triggers caudal vena cava syndrome in cattle?

bacteria from a liver abscess entering the bloodstream and causing a septic clot in the caudal vena cava

what does the septic clot released into the lungs in caudal vena cava syndrome lead to in cattle?

1. embolic pneumonia

2. vascular hypertension

3. fatal pulmonary hemorrhage

what is caudal vena cava syndrome in cattle commonly associated with?

ruminal acidosis from high-grain diets, which leads to liver abscesses that then erode the vena cava

what else is jejunal hemorrhage syndrome in cattle known as?

hemorrhagic bowel syndrome

what is jejunal hemorrhagic syndrome?

a highly fatal and acute enterotoxemic disorder primarily affecting dairy cattle, characterized by blood clots and sloughed intestinal tissue that obstruct the jejunum

what is strongly associated with jejunal hemorrhagic syndrome?

clostridium perfringens type A

what are potential risk factors for jejunal hemorrhagic syndrome?

1. high energy low fiber diets

2. feed changes

what is the treatment for jejunal hemorrhagic syndrome?

1. supportive care

2. surgery to remove blood clots

what is the PCV range for a cow?

30-35%

what is the PCV range for a horse?

about 40%

what parameters will indicate a large animal needs a blood transfusion?

1. increased HR

2. increased RR

3. body temp may be low

4. pale mucous membranes

5. depressed

what is the rough blood volume of animals of their total body weight?

8% (80mL/kg)

MCQ: If an animal can lose 1% of body weight safely (in blood), how much blood can you take from an animal?

10mL/kg body weight

what percent of BW of blood loss would be considered critical?

3% of body weight

MCQ: If a cow/sheep/alpaca can lose 10ml/kg of blood safely, how much blood can you take from a 800kg cow?

8 liters

how is cross matching done in the field?

small amount (around 200 mL) of donor blood is given first, then observed for 10 minutes; if no reaction, the rest can be slowly

what is the best practice for blood transfusion donors?

1. use same breed

2. select healthy donors

3. avoid if animal already transfused

by how much percent should we aim to raise the PCV for every liter given?

0.5-0.75%

what supplies do you need for blood colleciton?

1. prepared bags

2. 1, 3, or 5-liter saline bags w/ACD* or heparin (if using immediately)

3. gallon distilled water jug

what is the infusion rate for the first 5-10 minutes in large animals for blood transfusion?

0.1 mL/kg

if the parameters are fine after 10 minutes, what can you increase the transfusion rate to in large animals?

20mL/kg

what is the lifespan of RBC in horses?

150-160 days

what is the lifespan of RBC in cattle?

130-160 days

what is the lifespan of RBC in goats?

125 days

what is the lifespan of RBC in sheep?

114-133 days

how many RBC are broken down after a blood transfusion?

Post transfusion 25% gone within 24 hours

what is an important parameter to determine if you will do a blood transfusion in a horse?

heart rate

what percentage of blood can you take from the donor in horses?

15% of blood volume

what amount of whole blood will increase a horse’s PCV by 1%?

2-3mL whole blood/kg

what is sufficient in horses for transfusion?

replacing 30-40% of blood loss

how many blood groups are there in horses?

8

the best equine donors lack which blood type?

1. Aa

2. Ae

3. Ca

4. Qa

how do you calculate blood volume in a horse?

body weight * 0.08

how do you calculate the transfusion amount in horses?

[ (desired PCV - patient PCV) / donor PCV] * (0.08 * BW)

what test do we use to cross match in horses?

saline agglutination test

what is used for a major crossmatch test in horses?

donors RBC and recipient serum

what is used for a minor crossmatch test in horses?

recipient's RBC and donor serum