1) McGuire is an AIR FORCE BASE, not a Marine Camp! Marines are associated with the Navy, not the Army.
2) Nurses do not tap the air out of the syringe because it will kill you, those shots go in muscle, we do it to insure the correct dose. in your IV, it would take around 2 to 3 LITERS of air to kill an adult, and last but not least...
3) It is physically impossible to "swallow" one's own tongue.
All of which is easily checked with a simple Google search. Even if this novel was written internet access, still simple facts to verify, quite sloppy, and lazy on the author/editor's part.
It was one of the worst story lines ever and I've read all the books in the Jack Reacher series. It almost as if this book wasn't written by Lee Child and Dick Hill should be the narrator for all Reacher books, McClain sucks.
Juvenile dialogue poorly delivered. Not worth the money or time. Having every character repeat "no doubt about it" and "that's for damn sure" ten million times doesn't come across as authentic American dialogue. Thus novel really needed an editor.
I have a science background and I am fascinated with epistemology.
Transparent plot ,Neither Lee Child nor Jack Reacher's usual quality. Very shallow character development.
Figuring out the killer was too easy. I spent most the book just wanting to get to the end to confirm what I had figured out early on in the story.