I am not licensed in MA and can offer only general advice. The short answer is that whether you have a viable claim depends on the type of surgery your husband was having, whether the care was below standard or whether the result was a known risk of the surgery. It sounds like you have reviewed the consent form, but more facts are needed to determine whether you can obtain an expert to support your claim.
You should consult with an attorney and have the attorney request your husband's medical records and then have an expert to review them to determine whether the doctor's performance fell below the standard of care.
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