EPISITAXIS

A 60 yo female, episitaxis (nose bleed) on a sunday midnight, according to her, lots amount of blood was flooding out of her nose, then she checked her BP (according to her husband, it's 170, not sure about the diastolic pressure). The following morning, she got out of her bed, went to the bathroom, she almost lost her conscious and had blurred of vision, then was taken to her bed by the family. Another BP check, it's 90/50. After she fainted, she had another episode of epistaxis.

What is the etiology of her epistaxis?
Why did she almost lose her conscious?
What Questions a doctor should ask the pt in order to make the correct Dx and Correct Tx?
What a doctor should do to save this pt?
Is it just a minor incident (epistaxis) or is it a warning sign?

(I've already given out a lot of hints... not very difficult to figure out!!)