What Are The Side Effects Of Xarelto In Old Age?

Question: Hi. Mom was diagnosed with a kidney infection at the end of sept/14. on Oct 12 while staying at my sister's for the weekend they found her wandering at 3am not knowing what was going on and taken to emergency. the doctors were not told about her kidney infection and she was tested and monitored for 3 days and checked by a cardiologist on oct 14/14. she was retaining water and clots were found in her lungs so she was diagnosed with DVT and PE and prescribed Xarelto at 30mg daily for 21 days. she started Xarelto on Oct 15/14 and was dizzy very tired and disoriented the next day on. she was taken for followup to cardiologist Oct 21/14 and diagnosed with congestive heart failure stage 4 and sent to local hospital to die. fortunately lack of communication caused her to miss 2 days on Xarelto and she got better briefly, the next 2 weeks were very hard on her and she needed help getting out of bed to dress or groom. on Nov 5/14 she was reduced to 20 mg daily. her kidney infection was still there and had gone unnoticed or tested for. on Nov 10/14 on a regular visit when I walked in she was standing in the bathroom grooming herself. She started walking and functioning very well and doctors finally treated her kidney infection again. She has since been reduced to 15mg daily and is doing quite well physically and mentally except for the 4 hr period after her morning Xarelto.

Question: What impact did her kidney infection have on her taking Xarelto and was 30mg daily too much for a 95 lb 86 yr old woman?
Approximately Jan/13 Mom had knee replacement surgery which went quite well except Warfarin made her hyper and a little loopy at times. they kept phoned my brothers to ask if they could tie her down to her bed and was just right out of it mentally at times. a couple months later she had surgery on a blockage in her stomach. through all this she was diagnosed with congestive heart disease. the summer went very well for her and saw her couple times a week taking her downtime for bank, shopping etc and was never confused or tired. just a typical 86 year old woman until she got the kidney infection.

Dr. Shehu, thank you for confirming our concerns about Xarelto and Mom's kidney function. On Nov 27/14 my sister exercised the power of Attorney and Mom was assessed at stage 4 care in Alberta XXXXXXX assistance program. This meant she could only live in facilities for people with bad dimensia or ready to die. She spent last 2.5 months in facilities where almost no one could talk except the staff. Me and my brother took her to see her doctor for 3rd time in last month at her most recent home and he said she easily passed 3 mentally evaluations and he would be issuing a note recinding her previous assessment and get control of her life back. Now she can move back into her condo and get home care assistance and choose a facility she would like to be in if necessary later.

Once again Thank you for your advise.