Is it true that using the positive pressure or positive deplacement ports on PICC lines eliminates the need for Heparin flushes? Why is it necessary to use Heparin flushes with PICC lines having a "negative" pressure port. If the line isn't used for blood draws, why the need for heparin? Peripheral saline locks don't require heparin. The blood flow at the tip of the PICC is far greater than that of a peripheral site. Why Heparin?
First - there are **no** needleless connectors that exert pressure - they displace fluid by movement but pressure is not involved. So to call these a negative or positive pressure device is not correct.
Catheters with integral valves and some positive displacement needleless connectors make the claim of saline only because of their technology. When one of these technologies is not used, an anticoagulant is still required. In fact, when you look at the studies, there are still significant problems with occlusion with saline only flushes and these needleless devices - ranging from 6% to about 10%. Think of the cost of tPA declotting for that number of CVCs. Talk to anyone who has gone to a saline-only system and they anecdotally report that their tPA use has not decreased. The studies on short peripheral catheters ~20 years ago found that flushing with saline only was equal to but not better than a final flush of heparin. So it was a matter of cost containment to drop the heparin that was not adding any benefit. The same thing has not been demonstrated for CVCs. Regardless of whether you are drawing a blood sample, you still must be aspirating for a blood return with each use. The blood flow around the catheter tip is a separate flow system from the fluid flow through the catheter lumen. I am convinced that there are significant issues with heparin use, however I remain convinced that some type of anticoagulant is necessary to keep these CVCs patent. Right now heparin is the only choice we have, however that will be changing in the future as new products come to market.
Lynn Hadaway, M.Ed., RN, BC, CRNI
www.hadawayassociates.com
Lynn Hadaway, M.Ed., RN, NPD-BC, CRNI
Lynn Hadaway Associates, Inc.
PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861