Hi,
Thanks for posting your query.
With the available described symptoms, this can be concluded that your friend condition is extremely serious.
Cardiac arrest for 4 minutes is huge time period and this may cause
hypoglycemic encephalopathy in brain.
Sedation or comatose position could be result of
brain damage.
Further progression depends on heart status & combination of heart and brain damage.
Initial 5-7 days are very important as heart condition may improve or deteriorate progressively in these coming days.
He/ she should remain in close surveillance of expertise doctor team.
Pray for better.
Take care,
Dr. Mayank Bhargava