What can help skin irritation?
I’m sorry to hear that your grandmother is having so much trouble. Skin does break down after a time when someone is bedridden or unable to change positions.
When there is a wound in that area, it is called a decubitus ulcer. This ulceration can eventually become very deep, even to the bone, and be nearly impossible to heal. The best thing to do is prevent it from getting worse.
You are correct that the ideal would be to change her position frequently, since the cause is persistent pressure on the skin areas that prevents healthy circulation and oxygen flow. If that is truly not possible, keeping the skin well moisturized is definitely important.
Specially designed soft cushions with holes in the center can be placed under the area to keep pressure off, and there are highly advanced wound healing dressings that provide the right environment for skin to be best protected and which actively promote healing.
Finally, prescription wound healing gels can be used for severe problem ulcers. These attract wound healing cells to the area so the skin can heal itself. Ask your grandmother’s dermatologist or get a reference to a wound healing expert for some guidance.