My gerbil is dying pls help me?

HI there my gerbil is dying its very week and cold its still breathing but very slowly and its very tried it also cant open its eyes he had a stoke not that long ago and i took him 2 the vet and they said he should be okay but now he ain't i have stroked his fur and i still talk 2 him i have also put him in a wee towel 2 keep him warm but it isn't working can any1 pls pls help me