This forum is for questions and support regarding neurology issues such as:
Alzheimer's Disease,
ALS,
Autism, Brain Cancer,
Cerebral Palsy, Chronic Pain,
Epilepsy,
Fibromyalgia, Headaches, MS, Neuralgia, Neuropathy, Parkinson's Disease, RSD, Sleep Disorders,
Stroke, Traumatic Brain Injury
I'm sorry to hear about your sister's condition at the present. There can be several reasons why your sister cannot speak and critical illness polyneuropathy may not be able to explain that entirely. I would agree with the possibility of a stroke, but not as dramatic as one sees. These can be small strokes called "lacunar infarcts" which are small enough not to be detected on CT scan. These small infarcts can be a consequence of critical illness as well but should improve once there is recovery from the illness and rehabilitation. MRI can do a better job but with mechanical ventilation, it may not be practical or possible to do this. I hope your sister can recover soon.
Regards and God bless.