Generally speaking meads are served flat. Some sparkling do exist though... if you insist on carbonating I would use a champagne yeast like montrochet or Lavlin EC-1118 is pretty hardy. Make sure you rehydrate and I would not use a full packet. Maybe 1/4. make sure you rehydrate!
There are possibly still some yeast cells that are alive depending on the alcohol but there would definitely not be enough to carbonate nor would they be viable cells...Stick to fresh ones.
On Hiatus: Brewing at work....