INR

Question 1

Definition of INR

Answer 1

Measure of blood coagulation and is commonly monitored in patients on warfarin at high risk of thromboembolic events (E.g. those with prosthetic heart valves, AFM or those being treated for a thromboembolic event e.g. DVT or PE)

Question 2

Causes of high INR

Answer 2

Overdose of anticoagulant medication
Drug interaction
Herbal products
Increase in alcohol consumption
Decrease in consumption of foods containing vitamin K
Liver failure
Infection

Question 3

Assessment of high INR

Answer 3

History - dosing of anticoag, concurrent illness, change in meds/diet/lifestyle, history of falls/blood loss - malaena, bleeding gums, haemoptysis, haematemesis, FBC to check for anaemia/infection, clotting screen

Question 4

High INR management - concern re head injury consider…

Answer 4

CT head
If major bleed, stop anticoagulants, administer IV vitamin K and fresh frozen plasma/prothrombin complex

Question 5

Minor bleeding + head injury

Answer 5

CT head consideration
Stop anticoagulants
Administer IV VIT K
Repeat INR after 24 hours, may need repeat Vit k

Question 6

INR >8 but no bleeding

Answer 6

stop anticoagulants, administer IV or oral vitamin K, repeat INR after 24 hours

Question 7

No bleeding with INR>5

Answer 7

Withhold 1-2 doses of anticoagulant, review maintenance dose of anticoag