The Gemoro says (30a) that the Mishna goes according to R.Yehuda, and extinguishing for a Choleh which is Potur speaks about a Choleh Sheyesh bo Sakana, and Potur means Mutar.
The Gemoro said on daf 3a that there are only 3 cases in Hilchos Shabbos where Potur means Mutar (where one is doing an action) - wouldn't this be included?
Kol Tuv
Meir Eliezer Bergman
Manchester UK
Your Kashya must be a good one, because Tosfos on Daf 3a (DH 'Bar me'Hani' asks it). And they answer that whereas in all the other cases, it is not at all obvious that Patur means Patur u'Mutar (and Shmuel had to teach that the Tana does in fact mean that); whereas in the current case, which is one of Piku'ach Nefesh, it is obvious that Patur means Patur u'Mutar.