What Causes Blurry Vision, Neck Pain And Body Numbness After Caesarean?

My sister had a caesarean with an epidural 5 days ago. She’s not Breast feeding. She also has another child that they had to perform an emergency caesarean on because he was bridge. From this afternoon she is experiencing a blurry vision and a lot of pain in her neck and face and the left side of her body is going numb. What is the reason for this and what should we do?