In this day and age, we are still using the same archaic methods of extracting the wounded from an exposed position to safety. Unfortunately, it's a real good way to lose medics, as we typically will run out into the middle of the most dangerous situation. As they say, their is a fine line between stupid and brave. Once I find it, I'll embed a video of an attempted extraction during Fallujah, that resulted in 2 additional casualties, as well as the original.
So, what do we do. Well, several companies have begun to answer this problem. From North American Rescue, we have the High Threat Extraction Kit, which includes the Dragon™ Handle System, RAT Strap [Rescue Assault Tether], and the Hasty Harness, as well as some other carabiners, etc. The links will go directly a picture of the item. You'll also find the Dragon Harness seems to be a useful item. You wear it under your armor and your buddies can just come and grab you. Bear in mind, the strap on the body armor is not meant to be used for extraction. It will most likely break.
You can also go with the tried and true Poleless Litter, which is one of my personal favorite pieces of gear. I never went on patrol without one. Also, if your supply system sucks, you can always purchase tubular nylon and fabricate all this high speed stuff yourself. You can find training videos here
Just remember, whatever your extraction plan is, it needs to flexible and easy to implement. The battlefield is fluid and can change at a moments notice. Also, the plan needs to cover from point of injury to CASEVAC. And lastly, it needs to be realistic.