3009 - blood transfusion medicine

what are the main functions of blood

• Carry oxygen & remove CO₂ (RBCs, PCV)

• Clotting (platelets)

• Immune defence (WBCs)

• Transport nutrients, hormones, proteins (TP)

what is anaemia and why is it a problem

Low RBCs → ↓ oxygen delivery to tissues.

what are common causes of anaemia

• Blood loss (trauma, surgery, tumours)

• Blood parasites (Mycoplasma haemofelis)

• IMHA

• Drugs/toxins (e.g. onions)

what pcv indicates need for transfusion

~12–15% (but clinical signs more important)

what causes clotting factor deficiencies

• Rodenticide toxicity (↓ Vit K factors II, VII, IX, X)

• Snake envenomation

• DIC

• Liver disease

what test assess clotting

PT, aPTT, ACT

most common platelet disorder

IMTP (immune-mediated thrombocytopenia)

when does spontaneous bleeding occur

Platelets < 30 × 10⁹/L

what clinical signs indicate need for transfusion

• Tachycardia

• Tachypnoea

• Hypotension

• Dull mentation

what is fresh whole blood (FWB)

• <6–8 hrs old

• Contains RBCs, platelets, clotting factors

• Best for acute haemorrhage + coagulopathy

what is whole blood

• Stored up to 28–35 days

• ↓ platelets & clotting factors

• Used for blood loss

what are packed red blood cells (PRBCs)

• Concentrated RBCs

• Used for anaemia

• Lower risk of fluid overload

what is fresh frozen plasma (FFP)

• Frozen within 6–8 hrs

• Contains clotting factors

• Used for coagulopathies

what is frozen plasma

• stored >1 year

• Fewer clotting factors

• Still contains proteins

what is cyroprecipitate

Concentrated clotting factors from FFP

what is the most important canine blood type

DEA 1.1

why is the first transfusin in dogs “free”

no natural antibodies to other blood types

what are feline blood types

A, B, AB

why must cats always be blood types

they have natural antibodies → severes reactions

what happens if type A blood is given to a type B cat

fatal rection (death)

what is cross matching

testing donor-recipient compatibility

what is a major crossmatch

donor RBCs + recipient plasma

What is a minor crossmatch

Recipient RBCs + donor plasma

ideal canine donor criteria

• 1–8 years old

• 25kg

• Healthy, good temperament

• No prior transfusions

• Normal PCV/TP

how much blood is collected from dogs

~450 mL

how much blood is collected from cats

~10 mL/kg

how is blood stored

• Blood: 4°C

• Plasma: -18°C

• Label + agitate daily

what must always be used during transfusion

filter

Why avoid calcium-containing fluids

can cause clotting in stored blood

what is the starting transfusion rate

1–2 mL/kg/hr (first 30 mins)

total transfusion time

4-6 hours

how often should patients be monitored

• Every 15 mins (first hour)

• Then every 30 mins

• Monitor for 24 hrs post

Common signs of transfusion reactions

• Fever

• Vomiting

• Tachycardia

• Hypotension

• Facial swelling

• Urticaria

What is the first step if a reaction occurs during transfusion

Stop transfusion immediately

treatment steps for transfusion reaction

• Stop transfusion

• Oxygen

• IV fluids

• Drugs (adrenaline, antihistamines, steroids)

• Monitor (PCV/TP, plasma, urine)