Blood and Blood Products

Question 1

Define a blood component

Answer 1

A blood product manufactured in a local blood centre that is derived from a single donation or a small pool (4-6) of donations
Red cells, platelets, FFP

Question 2

Define plasma derivative

Answer 2

blood product manufactured from a large pool of plasma donations (1000s) using industrial type systems

Question 3

Priorities for the national blood service

Answer 3

• Min risk to recipients of blood products and to the crown (liability)
• Responsive to situations e.g. emergencies or potential infection risks
• Strategic direction and leadership
• Nationally consistent and accessible service
• protection of the gift status of blood

Question 4

CSL Behring Australia

Answer 4

• Plasma fractionator in melbourne
• Receives plasma from NZBS and manufactures into a range of plasma derivatives for use in NZ
  Products:
• Factor VIII (Biostate)
• Factor IX (MonoFIX, ProthrombineX)
• IV immunoglobulin (Intagram P)
• Human Albumin solution (Albumex)

Question 5

Strategies for maintaining a safe blood supply

Answer 5

use voluntary non-enumerated donors
Exclusion of potential donors who’s behaviour or lifestyle places them at increased at risk of acquiring recognised blood borne infections
Testing all blood donations for evidence of major blood borne viruses
Use of physical and chemical methods to destroy any pathogens that maybe present

Question 6

Examples of infections transmissible by blood

• Viruses
• Protozoa
• Bacteria

Answer 6

• Hep, HIV, Epstein- Barr
• Malaria, toxoplasma gondii
• Syphyllis, staph and strep, salmonella

Question 7

Paid donation associated with?

Answer 7

Increased risk of blood borne virus transmission

Exploitation of the poor and disadvantaged

Question 8

The precautionary principle

Answer 8

Risk is inherent in the use of blood products, it can never be said that there is absolutely no risk and that it is perfectly safe
Preventative agent should be taken when there is evidence that a potential disease causing agent may be blood borne, even when there is no evidence that recipients have been affected.
If harm can occur it should be assumed that it will occur

Question 9

Donor eligibility criteria

Answer 9

between 16-70
good general health 
able to donate blood every 12 weeks 
- complete health questionarre 
- interview with a registered nurse 
- Hemoglobin check

Question 10

Donor selection aims to protect

Answer 10

The potential recipient
- identify medical and lifestyle factors that might increase the risk to the potential recipient
The Donor
- Identify health problems that might increase risk of complications from donation

Question 11

In NZ all donations tested for?

Answer 11

ABO, Rh(d) type and antibody screen
Hep B surface antigen and nucleic acid test for HBV DNA
HIV 1/2 antibody and nucleic acid test for HIV-1 RNA
HTLV antibody (first time donors only)
Serological test for syphilis

Question 12

Mian clinical indication

• Red cells
• Platelet concentrations
• FFP

Answer 12

• Improve oxygen delivery to tissues in cases of anaemia or blood loss
• Management of prevention of bleeding in patients with low platelet counts
• Correction of abnormal coagulation on patients who are bleeding

Question 13

Restrictive vs conservative transfusion

Answer 13

use associated with at least as good clinical outcome, now check their Hb after giving each unit, to see whether they need another one

Question 14

Danger of using ‘older’ red cells?

Answer 14

One retrospective study of clinical outcomes found increased risk of postoperative complications when patients given blood two weeks or older.
However this study has been debunked
To date all control trials have failed to demonstrate any benefit from using fresh vs older blood

Question 15

The factors to consider when deciding whether to transfuse red cells

Answer 15

Signs and symptoms of hypoxia 
Ongoing blood loss 
Risk of anaemia to patient 
Risk of transfusion 
Hemoglobin, although important shouldn't be the deciding factor

Question 16

Red cell transfusion, specific factors to consider

Answer 16

Patients Cardiopulmonary reserve
- If pulmonary function not normal, consider transfusing at a higher threshold
Volume of blood loss
- clinical assessment should attempt to quantify the volume of blood loss before, during and after surgery, to ensure maintenance of normal blood volume
Oxygen consumption
- Affected by fever, anaesthesia and shivering
- If increased, patients may need more RBC’s
Atherosclerotic disease
- Critical arterial stenosis to major organs, particularly the heart may modify indications may modify indications for the use of red cells

Question 17

Hb levels and transfusion

Answer 17

<70g/L lower thresholds acceptable in patients without symptoms and where specific therapy available
70-100g/L appropriate during surgery associated with major blood loss, if there are signs or symptoms of impaired oxygen transport
>80g/L appropriate to control anaemia related symptoms in a patient on a chronic transfusion regime, or during marrow suppressive therapy
>100g/L not likely appropriate

Question 18

Describe platelet concentrations

Answer 18

A adult therapeutic dose: pool form 4 donations, or an aphaeresis machine donation
Specific component manufactured for neonatal use
Platelet con’s manufactures only from group O and A donors

Question 19

What is the normal platelet count?

Answer 19

150-400x10^9/L

Question 20

Indications for platelet transfusion

Answer 20

PROPHYLAXIS
Bone marrow failure
<10^9/L when NO risk factors present
<20x10^9 when fever and other risk factors present

Surgery and other invasive procedures
<50x10^9/L for normal surgery
<100x10^9/L for high risk surgeries e.g. ocular and neuro

Platelet function
may be appropriate in inherited and acquired disorders, platelet count unlikely to be helpful

Question 21

Indications for platelet transfusion

Answer 21

Patient bleeding
- When platelet count below trigger level and significant bleeding
Massive haemorrhage/ transfusion
- use confined to patients with low platelet counts and or functional abnormalities, who have significant bleeding from this cause
- May be appropriate when count 50x10^9/l in presence of diffuse microvascular bleeding

Question 22

Describe FFP

Answer 22

Plasma from single donation frozen within 6 hours of collection to <20 deg celsius
Vol approx 200ml
Initial dose where indicated 12-15ml/Kg
NZBS currently manufactures all FFP from male apheresis donors
Evidence from clinical audits indicates a significant level of overuse

Question 23

Donor and recipient matches (in terms of blood groups for FFP)

Answer 23

Opposite to red cells!!
O from AB, A and B (and O if it was collected but its not)
A from A and AB 
B from B and AB 
AB only from AB

Question 24

Indications for FFP

Answer 24

Replacement of single factor deficiencies where specific or combined factor concentrate not available
Immediate reversal of warfarin effect in the presence of potentially life threatening bleeding
Treatment of the multiple coagulation deficiencies associated with acute DIC
Treatment of thrombotic thrombocytopenia purpura
Treatment of inherited deficiencies of coagulation inhibitors in patients undergoing high-risk procedures where a specific factor concentrate not available
In bleeding patients with abnormal coagulation parameters following massive transfusion, cardiac bypass surgery or liver disease

Question 25

FFP not considered appropriate as?

Answer 25

volume expander in cases of hypovolemia
Plasma exchange procedures
Treatment of immunodeficiency states

Question 26

How are plasma derivatives manufactured?

Answer 26

industrial processes involving large plasma pools
Highly regulated
1-2 viral inactivation steps
good safety profile