First off, I am sorry for your tragic loss. It's horrible to have to endure the loss of a loved one, especially under such tragic circumstances.
You would want to contact a medical malpractice lawyer in your state. What this lawyer should do, is gather together the relevant medical records from your husband's hospital stay. Additionally, if you or your husband kept a diary or wrote down details during his ordeal, this should be highly protected. I would also highly recommend that if you have not written anything down about the ordeal (because you certainly went through a tough time) you should do so as soon as possible.
The lawyer you choose should send out the medical records to a relevant expert physician. That expert physician will render an opinion which will determine whether a case exists which is strong enough to go forward. Based on the medical records, the physician will attempt to determine whether your husband's doctors were negligent, and deviated from the standards of care.
I wish you luck with your case.
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