This documentary follows the emergency room of the 86th Combat Support Hospital (CSH) in Baghdad in 2005. It takes it as a series of vignettes of trauma cases that enter the CSH, a mix of traumas of U.S. military, Iraqi security and Iraqi civilians.
As a documentary, it keeps a very narrow focus on the trauma department. As such, it is graphic and raw in its depiction of the effects of combat. It does some introspection, with the main point that the members of the ER don't see anything changing (likely because they are too far removed). But the narrowness of their work make it not possible to see anything else. (and they properly stay in their lane, even when pushed by the documentary makers)
While this is the documentary that got awards, I like the NOVA episode Life and Death in the War Zone, which followed the 10th CSH immediately following the invasion in 2003. considerably better. While Trauma and operating rooms are flashier and more intense, "Life and Death" covers the hospital as a whole, starting with preparing for deployment and covering the activities of the whole of the hospital, which includes interactions with the outside world (i.e. other then Americans) while "Baghdad ER" is looking at war through a soda straw.