What is the best way for my mother with dementia to summon emergency help?

If your mother is past the point in her dementia where she can't use a phone anymore, she won't have sense enough to use an emergency system like LifeAlert that come with the pendants or bracelets.
It might be time to consider moving another person into the house. They could also help with some of the caregiving and give you some respite. It may be time to start looking at care facility placement for your mother. You yourself can get a LifeAlert system and wear the pendant or bracelet when you are at home.
My uncle was married to a much younger woman. He got Alzheimer's and declined very fast. His wife was his only caregiver and they lived pretty remotely. One day she had a heart attack and died instantly. My uncle was too out of it to remember how to use a phone. A couple of days had gone by and one of their distant neighbors who lived a ways up the road was driving home from work. He recognized my uncle who had wandered about half a mile from his house. Wearing incontinence soiled clothes and incoherent. He couldn't even tell the neighbor what happened, let alone what his address was. The guy called the cops and the police and they came. My aunt's sister always called her faithfully three times a week to check on them. She answered the last call. If this had happened in the winter my uncle would have been dead too.
Please look at moving another person in with you, or someone who will do daily checks on you and your mom.

There are devices that will alert the company if you should fall.
I saw an ad recently for the Apple Watch and the wearer had a fall and the watch called for emergency response with GPS location and apparently the emergency message repeats.
So these devices would be for you not your mom.
Do you have a friend that you could text each morning? I have a neighbor also a widow and every morning she sends me a text and I respond. If I do not get a text I will text her and ask if she is ok. I also have her daughters number and my sister has my neighbors number. It's kinda nice getting a text each morning and then replying with a greeting.
And the person you text does not have to be anywhere near you. If they do not get a response a call to your police or EMS can be made and a request for a "well being check" can be made. (I was on the phone with a friend a while ago and she had fallen and could not get up (why she called me I have no idea) but I got on my land line and called the emergency number in her town and I stayed on the phone with her until EMS arrived.)

Karin
There are devices that are supposed to summon help when the wearer falls. My DH aunt wore one for years. Mostly hers went off when she accidentally pressed it while changing her clothes or in taking it off. You might be successful in having your mom press the button when asked but her remembering to do so following an accident would be an unknown. I tried to build layers of help in keeping an eye on my DH aunt.

If you are concerned that you will pass out then perhaps you should arrange for a different type service or wear a pendant yourself?

I knew a couple of women who used the pendant to summon help when they really needed it but they did not have dementia. I sometimes think the pendant for aunt gave me a false sense of security that she would have help when needed.

I used home health for aunt as she qualified under the Medicare home bound benefit. This so she would have someone checking in on her several times a week.
If she had therapy going on through them, that was another layer of help.

Then I added meals on wheels who would call me if she didn’t come to the door.

Then she had a private aide for the mornings. I added cameras to make sure the aides were there and make sure aunt was up and about.

I hired a couple to come in at least once a week to restock, make her lunches, check the cameras etc.

When she went on hospice she had a daily aide from the hospice company. The private aides hours were extended and an evening aide was added.

During the worst of the pandemic when the aides couldn’t come, my DH and I stayed with her 24/7.
Then she was in an ALF for a few months and now at 95 she is in a NH … off hospice for now and doing rehab.
I worry about her there as well. I still have her evening aide check on her once a day.

I am sure there are better ideas. These are just the things I did to keep an eye on my DH aunt.

Good Morning,

I don't know how much your mother's dementia has progressed but have you thought about a local Day Program for Dementia patients. I am in a similar position and have often thought about this.

The Lifeline button is like a necklace. Once push and it connects to a speaker in the house. Help will be sent. But I think you need much more than this...please read below.

This is my plan--now that the Pandemic is over many of the facilities that host day programs have openings because everyone pulled their loved one out due to the Pandemic.

Pretty much everyone I know is vaccinated, Booster 1,2, you name, proof of purchase, a card in my wallet. There are different kinds of respite, some simply a Church facility basically almost like day care. But there are also programs that are specifically designed where a physical therapist, occupational therapist and speech therapist are all on site. An RN is on the premises and everything is geared with safety in mind and screening. Meals are served!

You may be able to secure a slot by contacting the Admissions Office of the facility. They in turn contact your mother's primary care doc for a physical, etc. and write the orders. There is an assessment. You could start your Mom with 4 hours, once a week starting how and see how it goes. Then you can do your errands with a clear mind.

I believe Medicare covers this. You have to find out from the insurance company. Basically, you have no back up it what it sounds like. This may be an opportune time to land a spot in a facility. You can check all of these places out online. Every facility has a website and usually one in the neighborhood for convenience is what most people do. Some even offer transportation.

I wouldn't leave it to chance and hope that nothing goes wrong. But the longer that this goes on you need peace of mind so if you go on errands you know mother is safe and you are not under pressure to return home if she doesn't pick pick up the phone on the 3rd ring.

You really can't live this way. You are not alone. This is quite common, but there are answers. I hope this helps as your story is my story.

Amen...