KUMJ | VOL. 15 | NO. 3 | ISSUE 59 | JULY-SEPT. 2017

Optimal Starting Dose of Warfarin for Treatment of Deep Vein Thrombosis in Nepalese Context, A Retrospective-Prospective Institutional Review
Shrestha BK, Karmacharya RM, Devbhandari M, Tuladhar SM

Background Deep vein thrombosis (DVT) requires an early establishment of effective anticoagulation in order to reduce harms and cost of concomitant treatments. Selection of the right warfarin dose at the start of treatment is important. Objective To know ideal starting dose of warfarin in adult with Deep Vein Thrombosis of our population. Method This is a retrospective-prospective single institution based analytical study including Deep Vein Thrombosis in adults from January 2015 to November 2017. On the first half (January 1, 2015 to July 31, 2016) of the study period, the cases were given 3mg of warfarin as initial dose (Group 1); while in the second half (August 1, 2016 to November 31, 2017) cases were given 5mg as the initial dose (Group 2). Two sequential International Normalisation Ratio (INR) within therapeutic range is considered as target attained. Result There were total of 63 patients (M:F=1:1.03) of which 85.7% (n=54) cases were acute deep vein thrombosis and 14.3% were chronic cases. Mean final dose of warfarin was 6.03 mg; where it was 6.50 mg in group 1 and 5.63 mg in group 2, p=0.11. Difference between final dose and starting dose it was found to be 3.5 mg in Group 1 while that was only 0.63 mg in Group 2 (p<0.01). Conclusion Lesser change in dose of warfarin from its initial starting dose (5 mg) was noticed in group 2. Warfarin 6 mg as ideal starting dose can be recommended but larger, multicentric and follow up studies are essential to substantiate the findings.
Keyword : Deep vein thrombosis, International normalisation ratio, Warfarin