I agree with Fred. I recently bottled some Imp. Stout after letting it age on some vanilla beans and Bourboun soaked oak chips for 7 weeks (10 gallons). After bottling 100 bottles, I realized that I forgot to add a little fresh yeast in my bottling bucket. I usually do these for extended aged larger beers, as I am concerned that the yeast could be popped out.
Well, I am happy to report that three weeks in the bottle, they are now correctly carbonated. Still, for insurance sake, I would typically add a little fresh yeast into the bottling bucket for aged beers with graviities exceeding 1.065 - 1.075. I usually add 1056 (tablespoon) to each 5 gallon batch that I am bottling and swirl it together with the priming sugars. However, you can use virtually any yeast, as the wort is effectively fully fermented. The only caveat I have to that is that I would avoid adding a significantly higher attenuating yeast to a bottling bucket full of a brew that had a lower attenuating yeast, for obvious reasons.