Hi. My Wife Is A 79 Year Old Woman Who

Hi. My wife is a 79 year old woman who has had multiple health issues over the last few years and is experiencing extreme weakness, tiredness and some confusion. She also has minor hand tremors. She is currently preparing for a reversal of a colostomy she had in January. She is also being treated for cirrhosis of the liver and has a history of arrhythmia which right now is mostly normal thru medications. My question is why the weakness? She tries to exercise but gets really tired after a 20 minute walk assisted by a walker. She has also developed extreme itching mostly at night and on her back. Any ideas?