Many of our favorite runs are pretty remote. For many runs in West Virginia, it may take a team of emergency responders a half-day to reach you - AFTER they have been properly contacted. Unlike urban locations, cell phone coverage might not be available. It doesn't hurt to carry your cell phone in a dry bag, you might get lucky if you have a decent wireless provider like Verizon or AT&T.
It is essential to properly prepare for that initial contact for professional help. As a general rule, serious injuries can't wait that long - First Aid needs to be started quickly. For your piece of mind and your fellow paddlers, it only makes sense to get proper First Aid training.
As instructors, you are required to present proof of both current CPR and First Aid training. If your class is conducted in an area that is over 4 hours from the nearest hospital, the first aid training level must be Wilderness First Aid or higher. Here is some further information on this topic: First Aid Training options.
First Aid skills become rusty just like throw bag skills. It isn't a bad idea to do some volunteer work for a major event like the Sierra Club One Day Hike. The Center for Wilderness Safety is a great organization to volunteer through. They often provide extra training for free, all the first aid gear, and exceptionally qualified personnel. These special events attract hundreds of persons and you will get lots of useful practice during the course of a day - not a bad investment in time.
Here are some more articles that might interest you: