What do my husband and I need to do with his mother, who has dementia, when we go on vacation?

I would contact the assisted living facilities, nursing homes and board and care homes in your area and ask if they do respite care and how you set that up.

She will probably need to have a tuberculosis test and a needs assessment done for anyone to take her, even for a short time.

I would recommend that you get it for a month, after 10 years she must be pretty advanced and it would do your family good to have a vacation and a staycation for a couple weeks. It is important that all of you get a chance to recharge your batteries. If your vacations are like ours, you need a vacation to recover from the vacation. So I recommend taking extra time, it could possibly be less expensive by the month.

Best of luck finding a place for mom and enjoy your vacation!

Can you put her in respite care?  contact your local senior center or county dept of aging?  Many facilities offer respite care (they need to fill beds which are temporarily available when residents are in the hospital, but will be returning)

We hired a retired nurse who we called “the house sitter”. We were gone two weeks...it was heavenly. My mom is semi-independent, but the “house sitter” did visit with her, take meals, and make her coffee. Most importantly, she stayed at the house and was here for emergencies.

Respite care or hire a service, we hired one for my mother to stay overnight with her. Wasn't inexpensive but worth every penny.

You will have to put her in respite care. Most Assisted Living facilities offer this short term stay option.
Or you can hire an agency, like Visiting Angel's, to stay with her. They offer 24 hour care.

I would explore paid caregivers to provide for her care in the home round the clock..Explore 2 people for 12 hour shifts and begin with them now so you can make sure you like what you see.
Look at putting her in adult daycare if only one reliable person can do it.
Explore care.com to seek possible providers

Call around to ALs. Some NHs will do respite.

Respite care through a home health care aide... start talking to home health care agencies.

Nursing home or Respite facility is likely to be a self-pay situation, but it would be worth the money to get the vacation you need. Think of it as part of the vacation expense.

Temporary respite care in a senior housing facility that offers short-term stays. This can be utilized for illness, vacation, surgery, or only a rest.