How do I manage to get enough sleep while taking care of my Dad?

Last night I was up for about 1 1/2 hours 2 trying to check my Dad’s glucose levels and make sure he is ok but how do I make sure I don’t have to be up all night constantly worried? I normally work at 4:30 every morning so if I have to go to sleep then wake up for that amount of time that means I lose at least an hour of sleep which I can probably make it work with that, but I don’t wanna go to sleep at 9 then wake up at 1 then stay up until almost 2:30 then go back to sleep then wake up at 4. If I have to go to sleep at 8 then I’ll do that.