when I was an emt we were always taught it was a last resort unless arterial. They change this now?
I let my EMT expire in '08 after 20 years...I hadn't been active in a few years, and decided so much had changed if I went back active it would be worthwhile to just repeat the whole class...as much of a PITA that would be.
And yes, they emphasize using a tourniquet much more nowadays.
Not that all systems have necessarily updated their protocols yet, but basically if you can get them to a hospital within 2 hours go ahead and use the tourniquet first for any major bleeding from an extremity. Most places, most times you're well within that window.
Tourniquet First! - Major Incidents - @ JEMS.com
The older, last resort recommendations had come out of the WWII experiences where soldiers might have spent hours on a battlefield before evacuation, and even after evacuation the aid station might not have realized there was one in place (covered by blankets, etc).
Of course if you're the only guy who can climb in the area and you're up in a tree you may end up pushing that 2 hour window even if you were trimming trees across the street from a trauma center, because the vast majority if not all fire departments if they can't reach you with a aerial tower they are going to look like a monkey fornicating with a football trying to get you down.
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Speaking of Monkey Fornicating Football, as I recall the "back story" this first incident was witnessed by a rescue-trained arborist whose assistance was initially declined -- but he hung around while the hilarity ensued (included bringing a Coast Guard chopper 50 miles inland, and the closest base I know with one is Cape Cod 150 miles away, to try and lower a rescuer into the tree top) until they finally decided he was the best option.
Then they gave him a lesson on the rescue harnesses the rope team had, and he went about his business efficiently to tie off the plane to secure it, put in points to lower the victims from, and get them in harnesses to be lowered to the ground once they climbed out of the airplane.
http://www.masslive.com/news/index.ssf/2008/08/antique_biplane_crashlands_in.html
And three years later with almost the identical situation, they decided they should call him in to help:
http://www.firehouse.com/news/top-headlines/conn-pilot-rescued-aircraft-stuck-tree