i can agree that this is an issue that most of the healers(and sorc/wiz) are struggling with, the usage of many revive skill on one person can put risk of failing in a certain part or boss since if the revive skill is on cooldown there is no way other than respawning to bring that player to live, and therefore the damage on boss per second is reduced.
i would suggest to put a visual effect such as a cross on that player so it will resemble that this player has been given a revive skill or as bluegum as suggested, write a notice in the chat