Brief Answer:
Cognitive deterioration - post stressful period.

Detailed Answer:
Hi,
Thanks for asking.
I am Dr. Prakash HM and I will be answering your query.
Based on your query, my opinion is as follows:

1. It appears to be a condition called as postoperative cognitive dysfunction or deterioration.
2. In the elderly, during major hospitalization (which is very stressful, at this age) or other stressful conditions, the cognition deterioration is very rapid. Normally, cognition deteriorates very slowly, however, during major surgeries or stressful periods, it is accelerated. The exact cause is not yet identified and is known to occur very commonly after major hospitalization or surgeries.
3. At present, it may not related to any medication. Dilaudid might be causing drowsiness, and not that it is withdrawn, he should be able to stay awake.
4. He will take some time to recover. It could be months, before he is back to the same pre-hospitalization stage, but it is possible. He will require:
a. Gentle care-giver assistance all round the clock
b. Family support
c. Social involvement
d. Activity involving family and friends is very important. The more he is active around, the faster the recovery.
d. Getting back to his usual familiar surroundings, if possible back home would be very helpful.
e. Physical therapy is only for back. He will require more regular daily involvement activities and his regular life to be active. Strong communication with him, allowing him time to respond and having lots of patience will be helpful in recovery.

If hallucination is severe or affecting his daily life, medications may be necessary. Psychiatrist opinion will be necessary.

Hope it helps.
Any further queries, here to help again.

Dr. Prakash HM

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