via a recent post from the Procedural Pause:
use a saline ‘bullet’ (dropper), drip a little saline on the fluorescein strip, then draw it back up.
handy for peds, or for squirmy adults, too
I’ve also seen the strip dropped in the back of a 10 cc syringe, or a saline flush used similarly as with the dropper above (see this ALiEM post for more).
There you go. Add it to the toolbox.
References: procedural pause post, ALiEM post