As someone else brought up (statute of limitations), there can be time limits involved. Going to an attorney once or twice should at least answer the basic questions (merits, time limits, etc). You will at least know the window of time you have for filing...you can then delay filing and spend as much time as you can with your wife.
Sometimes, docs do there best and still can't save everyone...in those situations, they did nothing wrong. Sometimes there are tough situations where a patient might have ambiguous symptoms and/or test results and the doc has to make their best guess based on their training, experience and judgment and still something goes wrong...not their fault. Then there are times when doctors knew or should have known about the risks of certain treatments that were not fully explained or where a doctor incorrectly interpreted a test result, or made a decision outside of their area of competence rather than consulting a specialist, or flat out made a boneheaded call where they should have known better...these are situations where doctors should be held accountable. The degree that they should be held accountable might vary depending many things.
Regardless, I'd think one visit to a competent attorney would be a good idea. Then you could decide what you want to do from there (delay, drop the idea, etc).