question about Port -a cath in kids... very random.

[Certifiable, BSN, RN]

I'm looking through a powerpoint presentation, and the instructor wrote "Hickman and PICC 2 ml of 20 U Heparin to "wash" (English is not the language i'm taught, so i'm translating here) in a child over 5 kg". but in a Port-a-cath it's 5ml (50 u)...

Soooo my question is thus: If the Port is technically closer to the SVC (no long tubing like the PICC or Hick), why would you use more Heparin? wouldn't you use less? wouldn't there be less chance of clotting ?

Or is the thought that because it's closer it's more a risk for sending bigger clots so give a bigger dose?

[HouTx, BSN, MSN, EdD]

Portacath has a reservoir that has to be flushed also - the others are just tubing. Does that make sense to you?

[Certifiable, BSN, RN]

Yes, thank you.