If I choose Hospice care for help, will it deduct from the hours I am getting with In Home Supportive Services?

I am my mom's caregiver. I have been my 92-year-old-mom's caregiver for four years. In the past year, she has developed water on the brain, congestive heart failure, and has had several mini-strokes. She is either bed or chair ridden 24 hours a day. It kills me to see her like this and I was told hospice can actually make her feel better. Her doctors have told me to "prepare" myself.
As cold as it sounds, my mom is my only support. If I sign her up with hospice, will the hours they work be deducted from my 200 given hours a month I am (she is) getting from IHSS?