I don't play a lot of tables so I run into this sometimes, too. I find that if I'm at a table for too long, and am card dead, then one of two things happen. Neither of them particularly good.
Either I start "pushing" a little more, playing hands that, although not terrible, are hands I wouldn't normally play. This puts me into situations that I'm not comfortable with post-flop and usually results in me spewing money.
The other possibility is that I remain disciplined, only play decent hands in decent situations, but since I'm card-dead this doesn't happen. Then, by the time I finally do get a hand, everyone at the table, even the biggest donkeys/fish have me pegged as super-tight and will give me no action.
So its kind-of lose/lose. My solution is to just leave the table and open a new one, regardless of how good the table I'm leaving should be. Technically, this is probably a -ev move, since you should stay at your good tables. But, in reality, it's a +ev move for me to leave even a good table after a while if I'm totally card-dead there and move to another table, even if its not as good.
In my case, if I've set at a table for, say, an hour and played a whole 2 hands, there is no point in staying no matter how good the table should be. Either I start spewing out of frustration, or I get no action if/when I finally get a hand. Just not much way to make any money in this situation. Best to just give-up and move.