A character for one reason or another can't go to a hospital, or even get another character to help, so they treat their own injuries. An oft-seen version of this trope (to establish the Badass credentials of a character) involves sewing the injury up, with or without the use of anaesthetic. They may also Heal It with Fire. May involve We Have to Get the Bullet Out or Life or Limb Decision. If the character isn't medically trained, it's probably an examplle of Worst Aid. If they are, it's a particularly extreme example of One of Our Own. Compare Pulling Himself Together.