My father went through with a laproscopic surgery (gallstone + bilateral hernia ) on 2nd Feb 2017. His valve is already replaced 10 years back and he used to take Acitrom 2 mg for 5 days and 1 mg for 2 days from last five years. His PT INR used to come around 2.5-3.7. We stopped Acitrom from 28th Jan 2017 and start Clexin injection 0.6. On 30th Jan his PT INR was 1.01 and he was operated on 2nd Feb 2107. Surgery was ok and after that Clexin 0.6 continued two times a day. He has severe internal bleeding after 2 days and his hemoglobin reached at 4.8 so doctor stopped Clexin for 2 days. He recovered in between and his hemoglobin reached till 8.3. After that Clexin 0.4 for once an day and after that twice a day. They start Warfarin 3 mg from 9th feb and daily PT INR test done (0.9, 1.01, 1.1, 1.25 ) then increased dose to 4 mg on 14 Feb. He is still on Clexin 0.4 with warfarin. Please suggest us how should proceed to get his PT INR 2.5-3.0 as it was earlier but without bleeding.