Blood products and their clinical use

Question 1

Common clinical indications for blood transfusion

Answer 1

Anaemia (PCV of 21%, [Hb] <5g/dL)
Haemorrhage
Coagulopathies/bleeding disorders
Thrombocytopaenia

Question 2

Acute vs chronic anaemia

Answer 2

With chronic anaemia, lower [Hb] concentrations are better tolerated owing to the establishment of compensatory mechanisms over time.

Question 3

Blood products

Answer 3

Fresh whole blood
Packed RBC
Fresh frozen plasma
Frozen plasma
Human/canine albumins

Cryoprecipitate
Platelet
Fibrinogen
Granulocytes

Question 4

Fresh whole blood

Answer 4

Ideally used to treat acute haemorrhage with loss of all blood components

Collected from a compatible donor and infused within 4 hours from collection

When platelets and labile coagulation factors needed

When stored products not available

Question 5

Packed red blood cells

Answer 5

Used when only red blood cells are needed e.g. immunomediated haemolytic anaemia, CKD, haemolysis

Perpared and stored for up to 6 weeks

Usually prepared in 0.9% NaCl with adenine and citrate

If large volumes infused: risk of thrombocytopaenia and hypocalcaemia as does not contain platelets

Question 6

Frozen plasma

Answer 6

Contains proteins and the non-labile coagulation factors

One specific indication is rodenticides intoxication - characterised by impaired function of the vit K-dependent coagulation factors, or states of hypoproteinaemia

Stored up to a year

Question 7

Fresh frozen plasma

Answer 7

Source of albumins and all coagulation factors

Frozen within 8hrs from collection

Maintains most labile coagulation factors

Indicated for treatment of specific coagulopathies like Von Willebrand disease and haemophilia

Question 8

Albumins

Answer 8

In UK only human albumins are available for clinical use

Can be used to treat specifically hypoalbuminaemia

Generally well tolerated

Recommended dose are up to 2g/kg/day

Expensive

Question 9

Treatment of hypoalbuminaemia

Answer 9

Plasma: requires n45ml/kg of plasma to increase albumin conc by 10g/L

For 10kg dog: massive volumes infused

COnsider early nutrition or albumins infusion as alternatives

Question 10

Adverse reactions to blood product infusion

Answer 10

Vomiting
Urticaria/skin rashes
Tachycardia
Hypotension
Hyperthermia
Hyperventilation

Start at slow rates: 2ml/kg/h for first 10 mins

Risk of bacterial growth decreased if product administered within 4 hrs after opening - fully administer or throw out

Question 11

Cross matching for use of blood products

Answer 11

Major crossmatch: detects antibodies in the recipients serum to the RBCs of the donor

Minor crossmatch: detects antibodies in the donor serum to the recipients RBC for plasma infusion

Question 12

General guidelines for blood product voumes to infuse

Answer 12

Fresh whole blood: 20-30 ml/kg in 2-6h

pRBCs: 10-20 ml/kg in 2-6h

Albumins: 1-2 g/kg/day

Once opened, one bag should be given in no longer than 4 hours

Question 13

End points to monitor when administering blood products

Answer 13

Optimise oxygen delivery to tissue by increasing oxygen carrying capacity and cardiac output

Treat tissue/metabolic acidosis

Restore circulating volume/perfusion

Improve coagulation

Improve hypoalbuminaemia

Question 14

Clinical evaluation of perfusion

Answer 14

Mentation
Heart rate
Respiratory rate
MM colour, hydration, CRT
Pulse rate and quality
Urinatio

Question 15

Instrumental evaluation of perfusion

Answer 15

Heart rhythm
Arterial blood pressure
Blood lactate serum concentration
Urine output (measure ins and outs)