Haemophilia and coags

Question 1

What is Haemophilia A?

Answer 1

Factor 8 deficiency
Sex-linked recessive bleeding disorder

Question 2

What is haemophilia B?

Answer 2

Factor 9 deficiency
Sex-linked recessive bleeding condition

Question 3

Define severe haemophilia?

Answer 3

Less than 1% factor present in blood

Question 4

Define moderate haemophilia?

Answer 4

Between 1-5% factor present in blood

Question 5

Define mild haemophilia?

Answer 5

Between 6-40% factor present in blood

Question 6

What level of haemophilia would you treat in practice?

Answer 6

Mild haemophilia - just expect prolonged bleeding and risk management
- Treat early in the day
- Limit initial treatment area
- Strongly consider suturing and packing
- Normal haemostatic control

Should be reviewed at a haemophilia centre every 2 years

Question 7

When should INR be checked before treatment?

Answer 7

IDEALLY 24 hours before
If stable - checking no more than 72 hours before is acceptable

Question 8

How should someone on apixaban or dabigatran be managed for high-risk procedures?

Answer 8

Miss morning dose, take evening as normal

Question 9

How should someone on rivaroxaban or edoxaban be managed?

Answer 9

If they usually take in morning - delay morning dose and take 4 hours after haemostasis achieved.

If take dose in evening - do not change schedule

Question 10

Give examples of low-risk bleeding procedures?

Answer 10

Simple extractions 1-3
Incision and drainage of intra-oral swellings
Detailed 6PPC
Sub-gingival pmpr
Direct/ indirect restorations with subgingival margins

Question 11

Give examples of higher risk bleeding procedures?

Answer 11

Complex extractions - adjacent extractions that will cause a large wound or more than 3 extractions at once
Flap-raising procedures e.g. surgical extractions, periodontal surgery
Biopsies

Question 12

How should someone with severe haemophilia be managed?

Answer 12

Admitted to hospital/ haemophilia care centre
Assessed by haemophilia team post-procedure and may require hospital stay post-op for 24 hour monitoring

Question 13

What is the treatment for mild and carriers of haemophilia A?

Answer 13

Desmopressin/ ddavp
Mild - tranexamic acid - fibrinolysis inhibitor

Question 14

What is treatment for haemophilia B?

Answer 14

Factor 9 concentrate

Question 15

Warfarin MOA?

Answer 15

Vitamin K inhibitor
Inhibits production of vitamin K dependant clotting factors - Factors 2, 8, 9, 10 and proteins C and S

Question 16

Mechanism of action of dabigatran?

Answer 16

Anti-coagluant
Direct thrombin inhibitor
Thrombin converts fibrinogen to fibrin.
Fibrin FORMS clots
SO by inhibiting thrombin - clot formatino is impeded

Question 17

Mechanism of action of apixaban, edoxaban and rivaroxaban?

Answer 17

Factor 10a inhibitor which cleaves prothrombin to thrombin

Question 18

In what situations should anticoagulsnt/ antiplatelet therapy not be interrupted?

Answer 18

Patients with prosthetic metal heart valve/ coronary stents
Patients who have had pulmonary embolism or DVT in last 3 months
Patient taking anticoagulants for cardioversion (to slow overactive heart)

Question 19

Give examples of higher risk of post-op bleeding complications

Answer 19

Complex/ adjacent extractions that will cause large wound
More than 3 extractions at once
Flap-raising procedures
Gingival recontouring
Biopsies

Question 20

Dental procedures UNLIKELY to cause bleeding

Answer 20

LA - infil + block
BPE
Supragingival pmpr
Direct/ indirect restorations supragingival margins
Orthograde endo
Denture work
Ortho