Brief Answer:
You Need to discuss with your doctor in charge
Detailed Answer:
Dear Friend.
Hi , I am Dr Anshul Varshney , I have read your query in detail , I understand your concern.
He is in a critical state and , there can be multiple reasons for his problems.
Kidney Failure if has occurred can be "Acute" or "Acute on chronic kidney disease"
So, tell me , if he has pre-existing kidney disease.
Any previous history of
Hypertension or
Diabetes.
Gangrene of foot is mostly due to 2 reasons:
1. As a complication of diabetes
2. As a result of
peripheral vascular disease due to
smoking.
Alcohol directly does not usually involve kidney's as such. But it can cause
liver dysfunction and can cause kidney failure as an entity of Multi organ system failure (MODS).
If he had no previous kidney issues , current deterioration is unlikely to be due to alcohol or smoking.
So, the insurance companies would follow the diagnosis , that has been declared by your doctor in charge.
So , discuss with him , that what actually caused this condition. Also ask him by saying that his brain is damaged , he means to say he has some clotting / bleeding there (Cerebro vasular accident) or some thing else.
With the available information ,i am unable to comment further that what actually lead to him in this state.
This is my personal opinion based on details available here. If you still have any query you may please ask me.
Stay Healthy.
Dr Anshul Varshney , MD