This past weekend I went to Angleton (south of Hoston, TC) and took the TCCC Enhanced course - Tactical Combat Casualty Care - from Tactical Medics Group
It's a 2-day $415 trauma course and covers a lot, culminating in live scenarios replete with sirens, smoke and gunshots (blank). The actors (young trainee paramedics) are moulaged and are rigged with squirting blood, etc - very intense pressure and as real as it can get.
They also have a more civilianized version called TECC - Tactical Emergency Casualty Care - which is very popular. You'll sweat and earn these certs, but the boost in confidence is worthwhile.