Liver disease.....Help me please?

My mum has been taken ill due to vomiting blood...she has been an alcoholic for 14 years and has been in a pretty bad way (not suprising) i know that its because her liver doesn't function properly so therefore that blood backs up and goes any where that it should so its gone through the varices which has now burst......We have been told that they may have to operate to bypass the blood else where. Is this a serious operation? any help/advice wanted please