Having a low platelet count leaves your mother vulnerable to nosebleeds because it takes her blood longer to clot. And once she has one, they tend to recur. So you
want to try to prevent nosebleeds from starting in the first place, or at least break the cycle.
Nosebleeds tend to be more common during changes of season, particularly when the amount of humidity in the air fluctuates. Dry air dries out the mucous membranes and irritates the skin inside the nose. Inside the house, you can run a humidifier to keep the air moist. If your mother is using a free-standing heater, place a pan or bowl of water on top to add humidity to the air.
You can also try to moisturize the skin inside the nostrils. Using cotton swabs, gently dab a small amount of petroleum jelly or rich lotion inside your mother’s nose. Reapply often, including just before she goes to sleep at night. Also remember to reapply before your mother goes outside, particularly if there’s a dry wind. When your mother needs to blow her nose, remind her not to blow it too hard, as this often starts a nosebleed.
Once your mother does get a nosebleed, have her use her fingers to apply firm pressure just under the both sides of the bridge of her nose until the bleeding stops. She should keep her head raised; it doesn’t help to lower the head. If the bleeding doesn’t stop after 15 minutes of pressure, call her doctor.