Brain Aneurysm Support Community

Hallucinations and Delusions

Hi Guys,
My mother met with an accident 12 days ago. She had to go through carniectomy. The surgery was done on 4th Dec. She is now able speak, eat by her own hands, walk and use toilet without much support. Buy she having some issue with mental condition. She is not recognizing people correctly. She is also hallucinating during night.
Is this common and what should do to prevent it?