Subarachnoid hemorrhage and avm medical bills

While shoveling snow Dallas got a sudden extreme headache, dizziness etc.  In the Er they confirmed he had a subarachnoid hemorrhage and needed to see a specialist.   He was transferred to the neuro ICU at U of M where further tests revealed an AVM.  He will need follow up treatment and will be unable to work for a while due to lifting restrictions to prevent another hemorrhage.  At this time we have no idea what the bills will turn out to be or how long he will be unable to work.  The doctors are still trying to decide how to treat it and he remains in ICU