Heat stress; please help!

[Kneedles]

A heat wave is currently occurring where I live and one of my hens (five-year-old black sex link) is not taking it very well. I first noticed her behaving abnormally yesterday; she was idling (standing) a lot, ate nothing except raw egg, and her comb looked paler. I gave her some nutri-drops and saw her drink water once yesterday evening. Today I syringe-fed her pedialyte several times, and she has eaten a bit more (raw egg, cucumber, watermelon, and yoghurt), but still not much compared to how much she eats normally (she did not eat any pellets). I think her comb has regained some of its colour. She has been moving around more, except for when she stayed in a shaded spot for a long time in the afternoon.
She is not waddling, her crop and belly feel normal, her throat smells normal, and I thoroughly checked her for cuts or tumours, but found nothing. I think she may have laid an egg the day before she got sick, but I'm not certain.
Does anyone have suggestions for what I can do to help her fully recover?

 

[Ribh]

Ice blocks in her water & iced water bottle in the coop just to keep her a bit cooler. My girls are suffering too.

 

[Ribh]

Trying to think what else I have been doing...I water down the outside of the coop to cool it down once the sun sets & I know some people set up fans & misters. I leave the coop door open if it's still really warm when they roost. During the day I make sure there's a really damp spot in deep shade. They love that.