haem

Question 1

Causes of pancytopenia

Answer 1

Marrow failure/infiltration:

• aplastica anaemia
• myelodysplastic syndrome
• leukaemia
• myelofribrosis
• infiltration by malignancy e.g. lymphoma
• infection
• megaloblastic anaemia
• prolonged starvation

hypersplenism

• portal hypertension
• RA
• storage disorders

Question 2

Causes of prolonged PT

Answer 2

• Warfarin
• liver disease
• vitamin K deficiency
• DIC

Question 3

causes of prolonged APTT

Answer 3

• Heparin
• haemophilia
• vWD
• DIC
• Liver disease
• Lupus anticoagulant

Question 4

Causes of low fibrinogen

Answer 4

DIC or severe liver disease

Question 5

What is polycythaemia rubra vera?

Answer 5

• Malignant proliferation of a clone from one pluripotent stem cell
• leads to excess RBCs, WBCs and platelets
• hyper-viscosity and thrombosis
• JAK2 mutation
• common >60s
• aquagenic pruritis, erythromelalgia, tinnitus, facial plethora
• can get gout

Question 6

what is essential thrombocythaemia?

Answer 6

• clonal proliferation of megakaryocytes
• persistently high platelet count >1000 x10^9
• bleeding, thrombosis, microvascular occlusion
  
  • headache
  • atypical chest pain
  • erythromelalgia

Question 7

Treatment of polycythaemia rubra vera?

Answer 7

• Primary: venesection, aspirin 75mg, hydroxyurea and ruxolitumab if severe
• Secondary: vensection, aspirin 75mg, hydroxyurea

Question 8

Treat ment of essential thrombocythaemia

Answer 8

• Aspirin 75mg OD
• Hydroxycarbamide in high risk

Question 9

What is myelofibrosis?

Answer 9

• Clonal proliferation of abnormal megakaryocytes
• fibroblasts made instead of platelets
• causes bone marrow fibrosis
• haematopoiesis in speen and liver –> MEGALY
• B symptoms, anaemia, bleeding, infection

Question 10

Myelofibrosis blood film

Answer 10

• Teardrop RBCs
• leucoerythroblastic film - RBCs have nuclei

Question 11

Treatment of myelofibrosis

Answer 11

Allogenic SCT

can evolve into AML, can develop from ET or PRV

Question 12

Packed RBCs

Answer 12

• 1 unit increases Hb 10-15g/L or 1g/dL
• Transfused over 2-3 hours/unit
• Each unit prescribed separately on chart
• Special requests: irradiated, CMV negative
• Shelf life of 35 days
• Kept at 4°C

Question 13

When is irradiated blood required?

Answer 13

To prevent transfusion associated graft vs host disease in

1. Hodgkin’s Lymphoma
2. Congenital immunodeficiency
3. Stem cell transplant

Question 14

How are platelets given?

Answer 14

• 1 unit increases platelets by 20 x10^9
• Given over 30 minutes
• Shelf life of 5 days
• Kept at room temperature
• units kept on shelves that are shaking continuously

Question 15

How is fresh frozen plasma given?

Answer 15

• Contains clotting factors
• Use within 24 hours of defrosting
• 1 year shelf life
• Kept at -30ºC

Question 16

What is Cryoprecipitate?

Answer 16

• Factor 8
• Factor 12/13
• Fibrinogen
• vWF

Question 17

What is prothrombin complex?

Answer 17

• Beriplex, octuplex
• Factors 2, 7, 9 and 10
• Protein C and S
• Dose: 30 units/kg

Question 18

Indications for RBC transfusion

Answer 18

To correct anaemia:

• Marrow failure e.g. aplastic anaemia, leukaemia
• Haemoglobinopathies e.g. thalassaemia, sickle cell
• Chronic disorders e.g. renal failure, malignancy
• Severe haemolysis e.g. haemolytic disease of the newborn

To replace blood loss

• Blood loss during surgery
• Trauma
• other haemorrhage

Question 19

Indication for platelets transfusion

Answer 19

• Decreased platelet production due to
  
  • congenital BM failure
  • acquired BM failure
  • Dilutional thrombocytopenia
  • functionally abnormal platelets
  • platelet-destructive conditions

Question 20

Indications for fresh frozen plasma

Answer 20

• DIC
• Liver disease with abnormal clotting
• Coagulopathy of massive blood transfusion
• Factor V deficiency
• Warfarin overdose (vitamin K would be too slow)
• Thrombotic thrombocytopenia purpura
• Depletion of coagulation factors after thrombolysis

Question 21

Indication for fresh frozen plasma

Answer 21

• Same as FFP
• Haemorrhage after cardiac surgery
• hypofibrinogenemia

Question 22

Tests done before transfusion

Answer 22

1. Blood grouping - test for ABO and Rh - agglutination
2. Antibody screening - test for atypical antibodies
3. Crossmatching - mix patients serum with donor red cells

Question 23

What is acute haemolytic transfusion reaction?

Answer 23

• When red cells from the transfusion react with the patient’s anti-A or anti-B antibodies etc
• Can be immediate or delayed
• Can stimulate complement, leading to DIC (clots everywhere) or intravascular haemolysis

Question 24

Presentation of acute haemolytic transfusion reaction

Answer 24

• haemolytic shock phase:
  
  • urticaria, lumbar pain, headache, Chest pain, SOB, vomiting, rigors, fever, fall in BP
• Oliguric phase:
  
  • some have necrosis of renal tubles with acute renal failure
• Diuretic phase:
  
  • fluid and electrolyte imbalance following acute renal failure

Question 25

Treatment of acute haemolytic transfusion reaction

Answer 25

* Stop transfusion, check for ABO reactions/contamination * Maintain BP and renal perfusion * Saline, O2 and fluids * 100mg hydrocortisone (IV) and antihistamines for shock * Treat DIC - escalate, transfuse platelets or FFP

Question 26

What is febrile/afebrile non-haemolytic allergic reaction?

Answer 26

* may be due to antibody reaction targeting leukocytes in the transfusion * antigen-antibody complexes induce complement * symptoms: fever and rigors * Mx: stop transfusion until haemolytic reaction ruled out * new transfusion * paracetamol for fever

Question 27

What is post-transfusion overload?

Answer 27

* When too much fluid volume is transfused or transfused too quickly * caues pulmonary oedema and acute resp failure * Management: furosemide (IV) and high-flow O2

Question 28

What is TRALI?

Answer 28

* form of acute resp distress from transfer of leucoagglutin HLA anitbodies from donor plasma * causes endothelial and epithelial injury * presents within 6hrs of transfusion * sudden dyspnoea and tachypnoea, non productive cough, hypoxia, frothy sputum * may have fevers and rigors * CXR may show perihilar nodules with infiltration of lower lung zones * Mx: high flor O2, IV fluids and inotropes, monitor ABGs, urgen ventilation may be needed but improves within 2-4 days

Question 29

What is graft-versus-host disease?

Answer 29

* usually immunocompromised patients * between day 4 - 30 post transfusion * high fever and diffuse red rash, progresses to erythroderma * diarrhoea and abnormal liver function * preventable with irradiated blood

Question 30

Signs and treatment of post transfusion iron overload

Answer 30

* myocardial, endocrine gland and liver damage * Mx: chelation therapy with desferrioxamine

Question 31

What is post transfusion purpura?

Answer 31

* sever thrombocytopenia that occurs 7-10 days after any type of transfusion containing platelets, usually red cells * patient has become sensitised to a foreign platelet antigen during pregnancy or from prior transfusion * Sx: diffuse purpura and bleeding from mucour membranes, GI and urinary tracts * Mx: high dose IV immunoglobulin