I once hung out for half a day at a hospital in Bakersfield, CA to watch a surgery and they had several gunshot victims come in. So in the US it seems they are highly experienced with this kind of injury unfortunately.
I don't know if it applies in this case, but US trauma medicine has also benefited tremendously from the experience of doctors who worked in military hospitals.
Before the War on Terror, US Military trauma surgeons got experience treating bullet wounds by working rotations at hospitals near high crime/gang areas like Compton.
This is also true of traumatic brain injuries. A number of my doctors after a fairly serious (to me alone) car accident mentioned that they have a lot more information thanks to doctors treating victims of TBIs caused by explosions.