Welcome here on hcm.
First of all you get your mother general physical checkup done with routine investigations for the age needed.
You must keep a track record of your mother BP by an automatic BP recording machine doing by yourself.
Whenever you feel she has BP less than 120/70 than you must supplement her with extra table salt via water.
So that when she gets hypotension
she must not get it in severity.
She has to give her body more time to adjust a postural rise of body it mean whenever she rises from low body posture to higher one it should be as gradual as possible.
She should avoid sitting on the floor even in bathroom.
She should use a chair for bathing.
There must be some supporting structure so that she can rise with the help of them gradually.
She should take more proteins
in her diet.
If she wants to rise from a chair she must bend first and bring the head at lower label than rise his buttocks and make her lower limb straight than gradually raise her head to full height gradually as gradual as she need by her experience.