Final answer:
A nurse should flush a PICC line with 10 ml of normal saline when the line needs to be cleared of any potential blockage or to maintain patency. On the other hand, they should flush it with 5 ml of heparin when the line is not being actively used and needs to be locked to prevent clotting.
Step-by-step explanation:
A nurse should flush a PICC line with 10 ml of normal saline when the line needs to be cleared of any potential blockage or to maintain patency. Normal saline is a sterile saltwater solution that can help to flush out any debris or clots that may be present in the line.
On the other hand, a nurse should flush a PICC line with 5 ml of heparin when the line is not being actively used and needs to be locked to prevent clotting. Heparin is an anticoagulant that helps to prevent blood from clotting within the line.