If the anesthesiologist injured your phrenic nerve due to some misapplication of the nerve block, that is most likely malpractice. And if it's going to cause long-lasting or potentially lifetime, diaphragm paralysis or impairment, with significant life impairment, you would certainly seem to be entitled to significant compensation. Legally, you seem to have quite a viable case. The reason why you may be having difficulty finding an attorney who does wants to take this is that malpractice cases are expensive to bring and can take a great deal of time; the attorneys look for not just good but enormous payouts typically to entice them to take the case (almost all malpractice attorneys work on contingency, getting a share of the proceeds). If you are not currently working and may not go back to work, that diminishes the lost income/lost earning potential recovery you might get; and based on your age, you will receive less for lifetime pain and suffering than a younger person, because a 62-year old's remaining life expectancy  is less than, say, a 40-year old's. While your case could involve what for most people would be significant compensation, due to your age and job status, an attorney used to truly huge settlements or judgments might feel there is not enough there to justify the time and effort. Keep looking, though; you will find an attorney at some point, and the case seems worth bringing.