"Doctors are dripping the chemical that gives chili peppers their fire directly into open wounds during knee replacement and a few other highly painful operations."
"Don't try this at home: These experiments use an ultra-purified version of capsaicin to avoid infection — and the volunteers are under anesthesia so they don't scream at the initial burn."
Note the word "volunteers."
I would have loved to see that classified ad:
"Need volunteers with so we can dump hot pepper on their open wounds. Anesthesia included. Lemon, salt optional. Call Dr. Pepper."