In the ultra-macho action flick Rambo III, there's a famous scene where the titular hero seals a gaping shrapnel wound by cauterising it with fire and gun powder. Awesome, eh? But how feasible is this DIY surgery in reality? This video from The Medicine Journal explains the circumstances where it might not be such a bad idea.
If you don't have time to watch the clip, the short version is that you should only perform self-cauterisation if you're in an isolated location and bleeding to death. Even then, the risk of dying from systemic infection is depressingly high without antibiotic treatment. In other words, don't be like Rambo.