bloodwork from a PICC line or Portacath w/TPN running

[Gdschild]

Hi,Iam wondering if someone can help me with this issue. I have had 2 patients with portacaths or a PICC line that had TPN running and I needed bloodwork. I would stop TPN for 5 min. and then pull 10cc of blood for waste and then pull the blood I need for blood work. Afterwards I would flush with 20cc of NS and than 500 of Heparin with the portacath. The same thing happens with my patients that have a PICC line with TPN running except after blood work I flush with NS. Why do my lab work always come back so abnormal when TPN is running either in a PICC line or portacath?? I do pull 10 cc of blood for waste before getting bloodwork from PICC or portacath

[Reno1978, BSN, RN]

I was taught to flush with 10mL NS, pull back 10mL waste, draw blood needed for labs, and flush again with 10mL NS. For PICC, then flush with 2mL Heparin (100units/mL) and then restart whatever infusion is going. I haven't noticed any abnormal lab results when I do this.

What sort of abnormalities are you noticing? If the PICC has multiple lumens, are you shutting off the other infusion that may be running?

[BBFRN, BSN, PhD]

Yes- you should flush with 10cc NS, prior to drawing back your waste blood. This flushes the TPN out of the catheter. Otherwise, you will have falsely elevated electrolyte levels.

[BBFRN, BSN, PhD]

Thread moved to General Nursing Discussion to encourage more responses.

[iluvivt, BSN, RN]

You need to stop all infusions through all lumens when drawing from any multi-lumen CVC. TPN should be a dedicated line though.....you should not be using that lumen at all for blood draws (this is considered best practice to keep the risk for infection low as these patients have a higher risk for candida among other things). Make sure everything is shut off for one full minute...and yes one minute is enough considering how much blood is running through the SVC per minute. Also make sure you discard at least 2x the priming volume of your line....and do not mix up the discard with the sample. If you have a multi-staggered tip design catheter ( usually these are the percutaneously placed CVCs you should routinely draw from the proximal lumen.