Extracting Blood & Wazu

Many people have blood extracted from their bodies by injection for medical purpose. Does this terminate one’s   Wuzu or not?

If the blood extracted by injection is so much that it would have flowed off (if it was not for the injection), then the Wuzu will be invalid. Normally, this is the case when blood is extracted.

Riyadul Jannah V 2 No 1 P 12