I'm going to go out on a limb here and suggest that what you need is two lights. First, here is no way you need 400 lumens when working on a patient, so I am assuming that much light is needed when you are doing an area search at the scene to look for possible injured, etc. I would recommend something like the Nitecore EA41 in a belt holster for those times when you need to reach out and touch someone. Otherwise it will be out of the way yet ready at hand. For your regular light, I recommend the Streamlight ProTac EMS. It is a single AA light with 3.7 lumen (pupil exam), 10 lumen (general wound care), and 50 lumen (all around near area illumination) modes. It is small enough to be lipped if one needs both hands for a minute or two, and has a very nice pocket clip as well. Other options for close-up work would be the Nitecore MT06 penlight, at 32 & 160 lumens, using two AAA cells, or if accurate color rendition is important, the TerraLux LightStar 80 High CRI penlight at 50 lumens. It even has a rubber bite collar for no-hand use.
This would give you the option of having a smaller, lighter, easier to manipulate light for the close in work, and a brighter, longer lasting light for when larger area illumination is needed, which could also be used with its lower modes for close in work if needed. Remember, "Two is One, and One is None".