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1.The history and symptoms suggest the possibilities of partial involvement of the
kidney function can cause the extremity swelling / oedema.
2.CHF over a time period as a complications can be seen especially in the elderly aged person.
3.This also can be due to the
morphine usage as one of the side effect on the system - but however there might be a strong reason to indicate morphine.
4.Lucky you to spend time with your dad at the last few days of the life.
5.I would recommend to follow the kidney function tests, and manage the underlying medical condition as much as the treating doctor can able to do so. And you can spend your time with your mother in this hard time.
Good luck.
Hope i have answered your query,
any thing to ask ? do not hesitate to ask.
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