There are probably numerous examples, but this is the one I am most familiar with.
You are pursuing a lawsuit in which the defendant is 300 pounds, and shows other signs of being prone to a heart attack. Moreover, the subject matter is one that is particularly inflammatory to this particular defendant.*
You want to pursue a line of cross examination that would not "faze" the proverbial "reasonable person." But given the defendant's physical condition and emotional sensitivities, you fear that this line of questioning might cause a heart attack. You pursue this line of questioning and it does cause a heart attack. Does the defendant have a cause of action against you for "eggshell skull" issues? Or do "reasonable man" and "no wrongful action" considerations protect you against such counteraction for a rigorous cross examination?
*This was an employment civil rights case. Before the case was settled, I was planning to show the defendant a picture of a minority person driving past his home on "Main Street" (a well-travelled road in an exclusive suburb), and ask him how he felt about that. Then, how he would feel if a minority dated his daughter."