Lecture 18: Blood Products

Question 1

Donating blood, some key criteria and saftey steps?

Answer 1

1. Voluntary Non-remunerated donation
2. No risky behaviors
3. Testing all blood donated
4. Increasing amounts of processes to remove any pathogens
5. Between 16-70, good general health, upto 12 weeks between

Question 2

What is the window period? What tests are done?

Answer 2

This is the period where a person has an infection but the test that is used is unable to detect the infection in the persons blood.

• ABO, Rh(D) type tests
• Hep B
• Hep C
• HIV
• HTLV (first time)
• Serology for syphilis (more of a marker for risky sexual behaviors)

Question 3

Blood components?

Answer 3

A blood product manufactured from a single donation, or small pool, for the purpose of direct transfusion to a patient

In NZ all blood components are leucodepleted prior to transfusion

Come in a bag system of RBC, Platelete concentration and FFP

Question 4

4 Specific factors to consider when transfusing blood?

Answer 4

1. Patients cardiopulmonary reserve - if their pulmonary function is not normal then you may consider transfusing earlier
2. Volume of blood loss - Clinical assessment to quantify the volume of blood loss
3. Oxygen consumption - This may be affected for a number of reasons inc fever, anasthesia, shivering.
4. Atherosclerotic disease - Critical arterial stenosis to major organs particularly the heart may modify the indications for the use of RBCs

Question 5

What Hb level should you transfuse at?

Answer 5

Question 6

Indication for platelet transfusion?

Answer 6

Question 7

What is FFP and it’s collection?

Answer 7

Plasma from a single donation that is frozen within 6 hours of collection to -25 degrees. Approx 200mL and initial dosage of 12-15mL/Kg is given.

Most overused or incorrectly used blood product. Only men are used as females are more likely to have antibodies to WBC that are gained in pregnancy.

• Immediate reversal of warfarin (although better products now)
• For patients with severe bleeding and failure to clot for an unknown reason (if known then a secific product is used)

Question 8

Plasma derivatives?

Answer 8

Blood products manufactured using industrial processes involving large pools of plasma (7.5-13 tonnes)

Highly regulated activity with one or two viral inactivation steps providing a good current saftey profile.