From a chapter in my upcoming book, Soldier Doctor:

Ballistic Maneuvers
"Combat medicine often feels like close quarters contact.  Soldiers’ injuries demand critical attention. Their complex wounds can precipitate sudden complications leading to death. Physicians move almost instantaneously from one patient to another, from one wound to another, always focusing on rapid-fire intervention. Quick invasive procedures become routine. Diagnoses become moot; every patient has an assumed ballistic injury and critical blood loss. Emergency combat medicine contains its own violence of action; it’s more a medical assault than a medical treatment.  Speed is paramount.  I love it. I excel at it. Something in my personality and my genetic makeup aligns itself to the critical demands and the imminent danger of medical emergencies.  The nature of close contact and combat medicine puts me on a mental edge that functions like a “rush.” It provides a level of excitement that seems to fulfill a base craving or a need for danger and thrill and risk. I suspect that without emergency medicine, without the ability to function as a combat physician, I would simply rust from inactivity."