Unconscious after craniotomy

My 82 yr old mother had a bilateral craniotomy for chronic subdural hematomas 2 weeks ago with a history of hypertension and diabetes  She has also had a history of mini-strokes.  After 4 days to wake up, she was alert and conversational for 4 days. Then she became unconscious for 6 days now.  She has no fever and very stable vital signs (blood pressure is in range of 130/50 to 160/60, pulse ox of 96-100, pulse of about 70-80 beats/min).  Her MRI and CT scans show no new strokes and no rebleeds.  Her EEG show no seizures. What could be causing this decline in mental state?

[Abhijeet Ghosh]

Dear Friend,
Many thanks for the posting the question and giving me an opportunity to guide you.
Already a craniotomy has been done on her, which suggests the severity of the eposide of the bleed.
The present condition can be co-related to-
1) Old stroke/bleed having a prolonged effect on her condition, OR
2) Weakness which is not allowing the brain to re-organize and perform,

These are the only 2 basic causes of the present condition.
Please understand that i have tried to keep the explanation very basic and simple.
I think she must be in the hospital itself and you can really trust upon the treating doctors and believe that they have done a good work, as immediately post surgery she was able to talk/speak.
But sometimes the disease takes it's own course of progression and it becomes difficult to control. Hence constant doctor's advice would be must as he would require to observe the patient and do a GCS (Glasgow Coma Scale) monitoring, which is the best indicator to show whether the condition is improving or deteriorating.
I would suggest you to discuss the same with your neurologist.
Please feel free to discuss more with me, if you want any guidance / want to know what questions you need to ask from your treating doctor.
Regards