An Elderly Woman Is on Warfarin for AF. She Was Also Started on Antibiotics for a UTI

SGH 2002 Haem

Question 10

An elderly woman is on warfarin for AF. She was also started on antibiotics for a UTI. She is admitted with subdural haemorrhage after a fall. INR 6, Hb 104, Plt 200. Apart from the administration of vitamin K, what else would you give her? (a) FFP (b) Cryoprecipitate (c) Factor VIII (d) Blood transfusion (e) Platelets

Immediately rule out (d), not anaemic enough and will not aid in reversing anticoagulation. Also rule out (e) because platelet count is normal. Using factor VIII will not reverse effects of warfarin, thus will not decrease bleeding risks. Warfarin The anticoagulant effect of warfarin is mediated through inhibition of the vitamin K-dependent gamma- carboxylation of coagulation factors II, VII, IX, and X. This results in the synthesis of immunologically detectable but biologically inactive forms of these coagulation proteins. Warfarin also inhibits the vitamin K- dependent gamma-carboxylation of proteins C and S [5]. Activated protein C in the presence of protein S inhibits activated factor VIII and activated factor V activity.

IE: warfarin inhibits factors II, VII, IX, X

INR<5 INR 5-9 INR>9 INR>20 OR No bleeding No bleeding No bleeding Bleeding     Omit 1 dose Omit 1-2 doses Stop warfarin Stop warfarin

maintenance Vit K 1-2.5mg ō Vit K 3-5mg ō Vit K 10mg IVI dose (repeat as required) maintenance FFP if life dose maintenance threatening dose haemorrhage

Repeat INR in 12/24 and further Vit K if required    Recommence Recommence Recommence when INR 2-3 when INR 2-3 when INR 2-3

Cryoprecipitate Plasma which contains all FVIII, fibrinogen, fibronectin, FXII and vWF. Used to treat congenital and acquired deficiencies of fibrinogen and FXII. It is ideal for supplying fibrinogen to the volume sensitive patient.

FFP Contains stable coagulation factors and plasma proteins: fibrinogen, antithrombin, albumin, protein C and S. Indications - correction of coagulopathies, rapid reversal of warfarin, supplying deficient plasma proteins, treatment of TTP.

All guidelines recommend FFP rather than cryo, thus answer is (a).