Bleeding disorders

Question 1

What is disseminated intravascular coagulation (DIC)?

Answer 1

Pathological massive activation of the coagulation cascade -> fibrin deposition in vessel walls.

There is platelet (thrombocytopenia) and coagulation factor consumption in forming these intravascualr clots - so, we get bleeding elsewhere.

Question 2

Give 3 causes of DIC.

Answer 2

1. Sepsis.
2. Major trauma.
3. Malignancy
   - Advanced cancer
   - Obstetric complications
   - Acute promyelocytic leukaemia.

Question 3

What 3 things might lead you to worry about DIC?

Answer 3

DIC is a critically ill patient

Suspect if:
1) Severe sepsis or obstetric or malignancy
2) Shock
3) Extensive tissue damage - trauma/burns

Question 4

Clinical presentation of DIC.

Answer 4

1. Signs/symptoms of systemic collapse - oliguria, hypotension, tachycardia, confusion
2. Bleeding - bruising, purpura, haemorrhage, petechiae, oozing, haemturia, widespread ecchymoses (discolouration of skin due to bleeding caused by bruising)
3. Generalised bleeding from 3 unrelated sites = think DIC

Patient is often acutely ill and shocked.

Question 5

What results would you find on investigation of a patient to diagnose DIC?

Answer 5

Decreased:
- Platelets
- Fibrinogen
- Factor V
- Factor VIII

Increased:
- Prothrombin time (PT)
- Activated partial thromboplastin time (aPTT)
- D dimer
- Fibrin degradation products (FDPs)

Question 6

Name 2 things that are increased and 2 that are decreased in DIC.

Answer 6

Increased: PTT and APTT.

Decreased: fibrinogen and platelets.

Question 7

What is the affect on TT, PTT and APTT in someone with disseminated intravascular coagulation (DIC)?

Answer 7

All increased.

Question 8

What is the affect on fibrinogen in someone with disseminated intravascular coagulation (DIC)?

Answer 8

Decreased.

Question 9

Are fibrinogen and platelets increased or decreased in DIC?

Answer 9

Decreased.

Question 10

Other than treating the underlying cause, how would you manage a patient with DIC?

Answer 10

Call intensive care!

1. Platelet transfusion
   - Replace platelets if they are very low
2. Fresh Frozen Plasma (FFP)
   - To replace the coagulation factors
3. Cryoprecipitate
   - To replace fibrinogen and some coagulation factors
   - No ABO match needed
4. Red cell transfusion in patients who are bleeding
   - Stop bleeding - maintain blood volume + tissue perfusion

Question 11

Haemophilia A is due to deficiency of what clotting factor?

Answer 11

Factor 8 deficiency.

Question 12

Haemophilia B is due to deficiency of what clotting factor?

Answer 12

Factor 9 deficiency.

Question 13

What is haemophilia A?

Answer 13

X-linked (boys!) recessive inherited factor VIII deficiency.

Question 14

What is haemophilia B?

Answer 14

X-linked recessive inherited factor IX deficiency.
(Christmas disease)

Question 15

In what ages do haemophilia A and B tend to present?

Answer 15

A + B both tend to present in toddlers.

Question 16

How do haemophilias A and B present?

Answer 16

1. Bleeding into joints and muscles (haemoathrosis, arthropathy, haematomas)
2. In neonates:
   - Intracranial haemorrhage
   - Haematomas
   - Cord bleeding

Question 17

How would you diagnose haemophilia A/B?

Answer 17

Bleeding scores, coagulation factor assays and genetic testing.

Question 18

How would you treat haemophilia A/B?

Answer 18

IV infusion of factor 8 for A / factor 9 for B.

Avoid IM injections, aspirin, NSAIDs (bleeding risks).

Question 19

What is von Willebrand’s disease (VWD)?

Answer 19

Deficiency of vWF - leads to platelet dysfunction.
Tends to be in teenagers.

Question 20

What type of genetic condition is VWD?

Answer 20

Autosomal dominant.
On Chromosome 12.

Question 21

Describe the pathophysiology of VWD.

Answer 21

1. Deficiency of vWF
2. Resulting in reduced vWF activity
3. Platelets are unable to bind to damaged blood vessels
4. Resulting in platelet dysfunction
5. Thus: muco-cutaneous bleeding

Question 22

Clinical presentation of VWD.

Answer 22

Patients present with a history of unusually easy, prolonged or heavy bleeding.

1. Bleeding gums with brushing
2. Nose bleeds (epistaxis)
3. Heavy menstrual bleeding (menorrhagia)
4. Heavy bleeding during surgical operations
5. Bruising

Question 23

Diagnosis of VWD.

Answer 23

Based on a history of abnormal bleeding, family history, bleeding assessment tools and laboratory investigations

Question 24

Management of VWD.

Answer 24

1. Desmopressin can be used to stimulates the release of vWF (for mild bleeds).
2. vWF-containing factor VIII concentrate.

Question 25

Management of women with VWD that suffer from heavy periods.

Answer 25

Managed by a combination:

• Tranexamic acid.
• Mefanamic acid.
• Norethisterone.
• Combined oral contraceptive pill.
• Mirena coil.