As Ines said, there are different levels of coma...and therefore different ways of treating. Based on the patient's own respiratory effort and blood oxygen saturation, that'll determine what kind of assistance (if any) they need to continue breathing. If they're not breathing on their own, obviously they'll need to be intubated and on a ventilator. If they're still breathing on their own, but not maintaining their O2 sats, then they can eiter get supplemental oxygen or they can still be intubated to assist their breathing.
As far as internal bleeding...management depends on the site of bleeding and the amount of bleeding. With head trauma, they'll get a head CT (Cat scan) to see if there is bleeding and what type - if there's bleeding around the brain, they'll do surgery to drain the blood and try to repair the blood vessel; if it's within the brain there's really not a whole lot to do except hope it stops.
Abdominal injury is assessed with ultrasound in the emergency room (in most cases) some hospitals still use the older method of diagnostic peritoneal lavage - squirting water into the abdomen and then sucking it back out to see if there's blood and how much. Depending on the amount of blood, they'll either get a CT to determine the site of bleeding or go immediately to surgery. If it's the spleen, they don't automatically do surgery anymore...depending on the amount of damage, it can sometimes stop on it's own. If the liver or bowel or anything else is suspected to be damaged, they go to the OR.
Chest wounds pretty much guarantee a trip to the OR.
Hope some of that's useful,
Jill
