Anticoagulation and anti-platelet drugs

Question 1

What is injectable anticoagulation?

Answer 1

Heparins- unfractionated and low molecular weight heparin

Question 2

How is unfractionated heparin administered and how is low mw heparin administered?

Answer 2

Unfractionated heparin-Via infusion only active for a few minutes
Low mw heparin- subcutaneous injection 1x a day

Question 3

How does unfractionated heparin work and how does low mw heparin work?

Answer 3

Unfractionated- allows rapid control, rapid onset and quick end to effect, inhibits antithrombin 3 preventing its action RARELY DENTAL ISSUE
Low mw heparin- stops low level excess clotting without increasing bleeding risk
NO PRACTICAL DENTAL ISSUES

Question 4

What are the types of oral anticoagulation?

Answer 4

Coumarins and non-coumarins

Question 5

What are dental care procedures you should be cautious with for people taking these drugs?

Answer 5

Extractions, minor oral surgery, implants, periodontal surgery and biopsies sometimes

Question 6

What are some indications for anti coagulation?

Answer 6

Conditions where blood clots will form too readily on or in the circulation e.g. atrial fibrillation, DVT, heart valve disease, mechanical heart valves and thrombophilia

Question 7

Give an example of a factor xa inhibitor and a coumarin.

Answer 7

FXA- apixaban
coumarins- warfarin

Question 8

How is warfarin response measured?

Answer 8

International normalised ratio- normal is 2-3 and 3-4 in prosthetic valves and higher risk of DVT

Question 9

How often should warfarin be checked?

Answer 9

Every 4-8 weeks, more often if value is unstable and all patients should carry a recording anti-coag booklet

Question 10

What can upset the INR?

Answer 10

Foods and medicines interacting with warfarin

Question 11

How do we proceed with dental procedures likely to cause haemorrhage for patients taking warfarin?

Answer 11

INR and FBC blood test within 72 hours of treatment, 24 is preferred, early in the day + week, if INR <4 proceed with caution, apply local haemastatic measures and post-op instructions with contact number

Question 12

Which drugs increase INR when taking warfarin? 4

Answer 12

Amiodarone, antibiotics, alcohol w. liver disease and NSAIDs

Question 13

Which drugs reduce INR when taking warfarin? 5

Answer 13

Carbamazepine, barbiturates, cholestyramine, griseofulvin and alcohol w.out liver disease

Question 14

What medications to avoid giving to those dental patients on warfarin

Answer 14

Aspirin for analgesia, NSAIDs, azole antifungal drugs

Question 15

What are the hazards of taking warfarin?

Answer 15

Haemorrhage needing hospitalisation can be fatal, can be from trauma such as hip/bone fracture after a fall, soft tissue injury leading to bleeding in muscles

Question 16

How do you reverse anticoagulation rapidly in a hospital setting?

Answer 16

Vitamin K injections

Question 17

What are NOAC’s?

Answer 17

New oral anti-coagulants

Question 18

How do NOACs work?

Answer 18

Prevent the effect of Factor X- no need to monitor action, rapid onset within an hour, short duration of action (lost within a day)

Question 19

Give an example of a NOAC

Answer 19

Apixaban 2x daily

Question 20

How do we proceed with dental treatment for those with NOAC? Extraction aswell

Answer 20

Assess bleeding risk of procedure- treat earlier day, if its a higher risk procedure, miss/delay morning dose and restart dose immediately after treatment for once daily and omit 1st and take 2nd daily dose for twice daily, IDB if needed and local haemostatic measures
Extraction- do at beginning of the day at beginning of the week and keep for atleast 20 min post op to assess bleeding

Question 21

What are dental drug interactions with NOAC?

Answer 21

Safe with antifungals, antivirals, and local anaesthetic **