There are certain situations where immediate retreat is impossible. The two most common are when there are multiple assailants that have surrounded you, and when you are trapped or cornered with no avenue of retreat. If you find yourself surrounded by multiple assailants you must do two things immediately. First, assuming the assailants are within range, disperse a full 360-degree circle of spray at head level, again creating a barrier the assailants must pass through to get to you. This may break up the pack quickly, or it may not.
In either case, your second step is to quickly find the best escape route, and immediately take it since your life may depend on it! In order to do this you may have to target one of the assailants with the spray, spray him, and push past him quickly. This calls for a forward attack with the spray, which means you'll be entering a spray zone where you'll be affected. To lessen the effects, take a deep breath, close your eyes briefly, and plunge through quickly. Once you've broken out of the circle, face the assailants, ready to spray again if necessary, and continue to back up until you can escape and get help.
If you are cornered, the procedure is very much the same as when you're surrounded. Spray the assailant(s), hold your breath and close your eyes, and run the moment you see the assailant disabled. When using any tactic where you have to enter the spray zone, you will be affected by it. Ignore the effects as much as possible so you can escape and get help. As long as you don't take a full breath of the spray, and it has only incidental contact with your eyes, you'll be able to function well enough to escape and get help.