Jamie
Please listen to the others that have answered you. I believe your Mom has an infection. Jim used to get the shakes/chills ( riggers) a lot. He would not run a fever, nor would his blood test show any infection. It took getting doctors from infectous diseases involved to find that he had an infection in a pocket between his liver and diaphram - found via a CT Scan-look for extra air and fluid where it doesn't belong. No blood vessels in the area to speak of, hense the reason his blood work would not test positive for a true infection. A tube was put into the pocket with a bag attached for drainage. This drain and antibotics were the only thing that stopped his chills. I taught Jim how to do labor breathing, which I used during child birth, to help him get past the violent shakes. If your Mother starts to shake have her focus on a fixed object-don't let her take her eyes off of it, breath deeply through her nose and blow the air out hard through her mouth. You have to be there to coach her. Sometimes you must use a firm voice to keep her focused. Do the breathing exercise with her and keep encouraging her - tell her she is doing a great job, but to stay focused.
One time in the hospital when Jim had the riggers so bad....I had him doing the breathing exercises while a doctor sat there with her mouth open in shock. She told me once I got Jim calmed down and the shaking stopped she had never witness anything like this before.
Try it - it can't hurt. Practice it sometime when your Mom isn't having the shakes so she knows what she needs to do. It helps to relax a person. Jim laughed at me the first time I suggested it, but when he calmed down and the pain & shaking had stopped he looked at me and said, "Boy, that breathing exercise actually works!" I told him that I know it works - if I can have two babies without even an asprin by using these breathing exersices to relax....it can get you through your pain too.
Best of luck to you, don't give up!
TnFishersWife