Drawing blood from PICC

Specialties Infusion

Published

Specializes in Med/Surg, Homecare, UR, Case Mgt.

I have been taught how to draw blood from PICCS in several different ways.

Some RN's tell me t flush prior to, others say no need.

Some flush w/10cc then waste 5cc.

Some flush w/20cc then waste 10cc.

Some stop fluids for 1 hr other stop for 1minute.

What is the correct way?

Specializes in Infusion Nursing, Home Health Infusion.

There are some variations on this procedure and that is OK,as long as you are following the basic principles. Some steps are non-negotiatable and must be performed to provide the standard of care.

1. Check order ,gather supplies, wash hands and don gloves

2. If an infusion is running turn of for one full minute. You must turn off all infusions on multi-lumen lines. Some pumps deliver a small KVO rate on hold so shut -off or know your pump. Most patients can safely be off most meds for one min (some can not). Others may say longer shut off I can assure you one minute is enough as the volume dumping into the SVC per minute is very large.

3. Scrub cap for at least 15 seconds with alcohol (some use chlorhexadine now). I avoid takink off the cap so I do not have to take air embolus precautions anf postive pressure caps can stay on a week even if used for blood draws if they can be kept clean,

4. attach a 10 ml syringe and verify patency(pull back blood) and then vigorousely flush with the 10 ml.

5. Attach a 10 ml syringe to PICC and draw a discard. A discard amt can vary depending upon priming volume of the PICC. Discard at least 5 ml... 5-10 ml is OK. Priming volume of most PICCs is very low less than 1 ml.Please not a syringe method is recommended for PICCS. On tother types of CVC a vacutainer system can be used. INS recommends the syringe method on PICCS. Place your discard in a special place away from anywhere that you might confuse it for the sample. I walk ot to the sharps if I can. Draw desired amounts and keep the blood flowing b/c yes it can clot if you mess with it too much.

6. Fill required tubes and allow vacuum to pull blood in. Do not force it.

7. Immediately flush using a pulsatile (push pause) method . I double the saline after a blood draw (20 ml). Follow with Heparin if that is your protocol;

8, Label speciamens at bedside and resume your meds and fluids.

Extra tips. Do not pull out the blood so fast it vibrates b/c this can cause hemolysis and lytes that are intrcellular can become extrcellular like K+ and blood count can not be counted.

If you can not easily get blood or just a little blood try flushing and repositioning pts arm out. Try other lumen. If you persistantly can not get blood lumen needs to be treated with Tpa (probably has fibrin tail or build-up.

Ber ready with all necessary equipment. Do not draw the blood and the leave to go get the flush. I have seen many a nurse do this.

protect yourself and wear gloves

OK everybody knows wah your hands but do not forget to scrub that cap. Some nurses have told me they thought the caps were self cleaning.

hope this helps

Specializes in Med/Surg, Homecare, UR, Case Mgt.

more questions

1) If you flush w/20cc is it ok to waste only 10cc?

2) I was taught to use the same prefilled NS syringe used for flush for the waste. In other words, a prefilled syringe is attached and NS flushed thru the catheter. That syring is left attached and blood is drawn back for waste. Is this w/in protocol?

Specializes in Infusion Nursing, Home Health Infusion.

Yes that is acceptable practice and is exactly how I do it. Just for further information it is NOT OK to attach syringe and use part of the saline...detach it and the later on reattach it...in other words each syringe is a one time use. If a cap is a bit difficult to reach and close to the skin I put a sterile 2x2 or alcohol pad under it. Also,if you have a positive pressure cap you do not have to change the cap with every blood draw. It is OK to waste only 10 if you choose to perform the pre-flush with 20 ml. A 20 ml pre-flush is really not necessary but it is really important to immediately flush with a good volume(10-20 ml )after the blood draw.The priming volumes on all CVCs are lower than you would think. For example, most PICC lumens range from .4 ml to .8 ml. The largest volumes will be ports and tunneled CVCs ie.(Hickman,Broviac,Chest Groshong) and these range from 1-2.5 ml. So when you discard or flush you want to have 2x the priming volume of your type of line. So,if your line has a priming volume of 1 ml,your absolute minimum discard and flush would need to be 3 ml. Volumes in protocols should be selected to to cover all types of lines. I do not expect the nurses to learn all the volumes and protocols that would be way too confusing for nurses to remember a different flush for each type of line, I find I am a better nurse when I know exactly why I am doing something and then if I need to make a modification for some reason I know the theory behind it. Hope this helps you let me know. Mary

There are two good articles that you might want to check out. From Nursing2004,Vol 34,No.2 "Drawing Blood through a central venous catheter" by Nancy Moureau. It's brief,but she describes nicely the steps for both the discard method and the mixing or 'push-pull' method,which while not especially popular may have its benefits. She also mentions not discarding blood prior to drawing cultures.

The second and more in-depth article is Anne Marie Frey's piece from the Journal of Infusion Nursing Vol 26,No.5 2003, "Drawing blood samples from vascular access devices." It is the most recent and most referenced publication on the subject.

The one thing I'd point out is that the recommendation is to discard at least three times the lumen volume of the device. This amount will vary with the catheter's length and lumen size. This works out typically to 3-5ml's or less for most devices. In almost all cases,10ml of waste is excessive and iatrogenic blood loss has been shown to have negative outcomes for pt's.

Here is the full list of references I have on the subject--can't recall where I snipped it from,though.

1. Frey A. Intravenous therapy in children. In: Hankins J, Lonsway R, Hedrick C, Perdue M, eds. Infusion Therapy in Clinical Practice. 2nd ed. Phildephia: WB Saunders; 2001:561-591.

2. Miller K. Decreasing diagnostic blood loss for patients in critical care units. Dimensions in Critical Care. 1999;18(1):46-54.

3. Andrews J. A QI project to reduce nosocomial blood loss. Dimensions in Critical Care. 1998;17(2):92-99.

4. Vincent J, Baron J, Reinhart K, et al. Anemia and blood transfusion in critically ill patients. Journal of American Medical Association. 2002;288(12):1499-1507.

5. Keller C. Methods of drawing blood samples through central venous cathegers in pediatric patients undergoing bone marrow transplant: Results of a national survey. Oncology Nursing Forum. 1994;21(5):879-884.

6. Cosca P, Smith S, Chatfield S, et al. Reinfusion of discard blood from venous access devices. Oncology Nursing Forum. 1998;25(6):1073-1076.

7. Holmes K. Comparision of push-pull versus discard method from central venous catheters for blood testing. Journal of Intravenous Nursing. 1998;21(5):282-285.

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