The primary task I was thinking about for a scalpel blade was removing splinters. Over the years I have had plenty of splinters that were long and deep and required cutting skin to remove them.

I have used pocket knife blades. Sometimes they were sufficiently sharp, sometimes not. Due to the shape & size the incision is larger than needed to remove the splinter. A sharp #11 scalpel blade is an efficient, effective splinter remover. It can make a deep but narrow incision to remove a long splinter, imposing minimum damage to surrounding skin. And a cut from a very sharp knife seems to heal quicker.

A new sharp utility knife blade can do a pretty good splinter extraction.

A needle can be useful but leaves a ragged wound.

Emergency trail-side appendectomies will be relegated to more skilled professionals than me.

My thought is to carry the scalpel blade in my hiking kit but also in my car FAK.

The SAK Classic is a good idea that I have considered. Not expensive. The blade could be re-profiled to a pointier point. And sharpen extra sharp. I wish the Classic had two sharp blades instead of one and a nail file.

Lots of good discussion here.