Thanks for the very detailed and informative reply, it is good to know that you care so much for her.
The sleepiness can be a sign of many conditions owing to her medical history and the medications she is on. To start off with - Age, tiredness, fatigue and sleeping throughout the day can be due to senility itself.
However, the medications she is on are mostly opiods in nature and can induce fatigue, lethargy, tiredness and sleepiness through out the day as well as a groggy feeling when she is not asleep.
Electrolyte imbalances as in her case because of Furosemide (a diuretic - water pill) can cause deficiency of sodium and potassium and this can cause sleepiness and fatigue and an altered mental status.
Encephalopathy - a far fetched cause but can be due to liver failure due to a lot of hepatotoxic drugs in her script.
Insufficient blood flow to the brain - in her case due to carotid artery stenosis and/or the paccemaker disorder.
At the end although she does not show any other features of Hypothyroidism but this should also be added to the differentials since at her age more or less the symptoms are less pronounced.
To evaluate all the causes, there are simple tests both blood work and clinical.
She should have her full blood count, thyroid function tests, a full metabolic panel (serum electrolytes), liver function tests, kidney function tests, Doppler ultrasound of the carotid arteries, ECHO and EKG for the pacemaker and heart.
A level of opiods can be checked in her blood using simple blood tests for opiate levels and can be interpreted to be in excess and if so the doses can be modified.
Other than that sleep studies, EEG will also help rule out organic and inorganic conditions related to the brain itself.
She needs to check in with her physician for all the above tests and a detailed clinical evaluation. These seem like a lot of things to go about but most of them will be done in the first visit and the remainder on a given date.
Again, the list of differentials is long and once a condition is identified, it can be eradicated successfully with the proper medical attention - increasing her quality of life in her age.
Hope this helps.
Please click ACCEPT to credit this assist.
A bonus and a positive feedback will be appreciated.