Why are we assuming that surgery is an issur on shabbos?
These only apply when the object is used for an isur during the week. AFAIK saving a life isn't muktza CMIIW.
To clear some things up:
A knife designed to complete a surgery is malachto lissur, regardless if the specific surgery you are carrying it around for is going to be mutar, because pikuach Nefesh doche Shabbos. Malachto lissur is muttar ltzorech gufoi and mekoimoi anyways. Now you have a question if it is considered muktza machmas chasaron kis or not, which is much more strict. Since it's easily replaceable and is used that way, it shouldn't be.
As an aside, if it was considered malachto l'heter according to the Rav it would never fall under the category of muktza machmas chasaron kis (that category doesn't exist), while the MB maintains that it does.