Musar על שבת 302:8

A person who has a sick person in his household, is obligated not to slumber, and not to remain silent, and not to rest until he seeks all types of doctors and all sorts of remedies according to his means / until he achieves his objective. And if he is a needy person, and he cannot afford [proper diagnosis and treatment], the obligation falls on the citizens of his city and/or on the Bikur Holim Organization (lit - visitation of the ill society - ie, the illness relief fund). - to assign for him doctors and cures - and they should not be concerned about the great expenses, for they should consider how great is the mitzvah. Go and learn till where the obligation to heal applies, for behold they permitted our holy / strict Shabbat to be desecrated and to transgress upon the entire Torah in order to treat a person who was in mortal danger. As our the Talmud says "It is better for one to desecrate one Shabbat so that one may observe many other Shabbats." [shabbat 151a] And how much more so that it is proper to spend all the money in the world in order to save one Jewish soul - for it is as if one saved the entire world. And even if with all this effort the person still passed away, G-d forbid, this should not serve to make them regret and balk (at the money spent). Rather they should rejoice in their hearts knowing they did did what was required of them to do. To Hashem - they are doing the best that they can do - and Hashem will pay them seven times over in their laps with wealth and riches in their home.