Good morning Jeza,
I must point out that alcoholism in any form is outside my expertise and the “brain shutting down” as a cause of death, is open to wide interpretation but will do my best.
The most common causes of death in alcoholism are suicides,road traffic accidents, heart attacks, strokes, cancer and last of all cirrhosis........NOT cirrhosis.
The effect of alcohol on the brain is based on pharmacological principles and the upset of chemicals that transmit impulses (messages) from nerve cell to nerve cell(neurotransmitters.) I don’t think it would serve any purpose to you in taking this any further as it can be a pharmacological nightmare.
I presume that a post mortem was performed on your sister and that would identify the definitive cause of death. However in the absence of a post mortem, I would have thought that your sister may have had a massive stroke or heart attack.
Jeza, please understand that these are assumptions on my part based on the information available to me.
\\The Doc said her brain had shut down. Can you explain this to me please\\
No I can't Jeza...........only the scant observations that I have made above.