Random p**ping elderly dog

We have a 14.5 year old female lab. More and more, she just poops without even seeming to know it. Since she is a house dog, you can imagine the difficulty this presents. We have an appointment scheduled to discuss this with the vet, but we have mentioned it in the past and no remedy was offered.

We take her outside frequently now, as if we were house-breaking a puppy. We don't yell at her or anything like that. There's been no change in the environment. I think she just can't sense that it's about to happen. Sometimes it happens while she rests or sleeps.

Has anyone dealt with this?