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Warfarin

Starting treatment
Indications
Dosing and monitoring
Complications
Follow-up
Follow-up

The following features increase the risk of an intracranial bleed: a
  • supratherapeutic INR ( > 4.0)
  • previous stroke
  • prosthetic heart valves
  • old age 

Why?

Previous strokes and prosthetic heart valves increase the risk of intracranial bleeding

Outcome a Risk Factor PEER OR
(95% CI)		 NNH
(95% CI)
intracranial haemorrhage  history of cerebrovascular disease
independent 		0.8% 2.3
(1.4 to 3.7)		 100
(50 to 330)
  prosthetic heart valve
independent 		0.8% 2.1
(1.2 to 3.8)		 120
(48 to 660)

Expiry date: May 2003
Levels of Evidence used in grading these guides

With thanks to Drs. David Keeling, John Reynolds, David Sackett, Sharon Straus and Alan Townsend 
 for use of their anticoagulation guide on which this one is based.

Author   CM   Ball
Reviewer   A   Gallus
CAT Writer   CM   Ball