When you get back be brisk and cheerful - "well no-one's in hospital so that's all fine, you did a great job" and ignore all forms of whingeing. In answer to phone calls, if you can't switch your phone off altogether, then repeat whatever variation of "sorry I don't remember where X is, do your best" or "whatever you think dear, it will be fine, sorry got to go" suits you and then ring off. Make it his problem, not yours.
Obviously people with autism can raise children, but wondering if it could all be Linked.
It sounds more like OCD and sensory difficulties than autism but could be whatever. Either way, if he can't be left alone with his own children, then he needs to see a doctor and find a way to pay for childcare. Autism (etc) doesn't give him the right to use you as his crutch and he can't expect you to earn the money and raise the children without his direct help. With three children under 10 shopping, cleaning and (sometimes) cooking doesn't cut it as a parent.
if they stress him out and he ends up shouting in front of them, they will get scared / upset.
He has the choice to shout at them or not. He can choose not to. If he doesn't know what else to do then (as someone else linked upthread) a parenting class will work wonders. And if he thinks he can't control himself then yes, GP and referral, pronto.
If he can't work and he can't parent then he needs to see his GP and get referred on. That's very serious!
Agreed. And if he wont do that then he is a waster, with or without autism.
When I'm home he will purposely have things to do so he doesn't have to watch the children.
My own father was a bit like this. One of the Great Undiagnosed, in the days before anyone had heard of autism. But he did always manage to earn a living, he respected my mother, and when we got older he made a huge effort (at my mother's insistence) to be a better less shouty parent and to build a relationship with us his children. Whereas I'm not convinced your DH is going to make it.