How do you get emergency medical assistance on a wilderness camping trip?

wIt really depends where you are going and what you are taking with you. The best way is obviously by phone or radio so I would recommend bringing a mobile with you (bare in mind you may not always get signal). If you are properly in the wilderness then it is a certainty to bring a gps otherwise the. Medical services will have no idea where you are. Smoke signals can also be used but I wouldn't recommend this if it is emergency assistance. Small signalling mirrors can be useful to signal to aircraft (e.g. An air ambulance). Perhaps you could use a distress flair if you had to.