drawing blood with tpn running

moonshadeau, ADN, BSN, MSN, RN, APN, NP, CNS · May 28, 2009

First pause the TPN. Also try not to draw blood from the port that the TPN is running through. There is a higher risk for infection when you pull blood through the same port. The method that I have personallly found the best is to stop all meds running through the line, and to use the push-pull method. Flush with saline, aspirate, push the blood back (repeat 2-3 times without disconnecting) and then draw your sample. By using this method, you should be pretty certain that your result will be the most accurate, particulary when you have to draw lytes.

Daytonite, BSN, RN · May 28, 2009

these are the current infusion nurses society standards pertaining to this subject (jan/feb 2006 journal of infusion nursing):

66. phlebotomy (page s71)
- standard
  - 66.2 protocols and procedures for phlebotomy shall be established in organizational policies and procedures and practice guidelines.
  - 66.3 the nurse shall identify the patient by using at least two identifiers including, but not limited to, date of birth or photographs, prior to initiation of therapy or procedure; neither identifier may be the patient's room number.
  - 66.4 the patient and blood sample shall be positively identified at the time of collection. collection tubes, including those used for a discard or waste volume of blood, shall be clearly labeled with patient identifiers prior to leaving the patient's bedside.
  - 66.6 aseptic technique and standard precautions shall be observed.
  - 66.7 all hazardous materials and waste shall be discarded in the appropriate containers according to state and federal regulations.
[*]ii. blood sampling via a vascular access device (page s72)
- c. infusions should be stopped prior to phlebotomy.
- d. blood sampling should not be performed through an infusion administration set.
- e. for the neonate and pediatric patient, adult critical care patients, and those requiring frequent phlebotomy, the amount of blood obtained for laboratory assay including discard or waste volume should be documented in the patient's permanent medical record.
- f. only the volume of blood necessary for accurate testing should be obtained in order to avoid patient compromise.
- g. vascular access devices should be flushed with preservative-free 0.9% sodium chloride (usp) post-phlebotomy.
- h. blood samples should be transported in an acceptable biohazard container.

you should look in your facility policy and procedures for a policy and procedure on this. the ins guidelines are only a starting point.

http://www.sh.lsuhsc.edu/policies/policy_manuals_via_ms_word/nursing/c-30.pdf - blood drawing procedure from central lines is included in this article
http://www.bccancer.bc.ca/hpi/nursing/references/nursingbcca/c-080.htm - care and maintenance of central venous and open-ended right atrial catheters (includes procedure for drawing blood)

blondy2061h, MSN, RN · May 28, 2009

Pause TPN, clamp that lumen, draw off another lumen making sure you get an adequate waste.

ehatchett71 · May 28, 2009

I would follow the first poster's directions, but would also state that you should shut off the TPN and wait 30 minutes before drawing your sample. That's the P&P at the hospital at which I work.

MoopleRN · May 28, 2009

Flush with saline, aspirate, push the blood back (repeat 2-3 times without disconnecting) and then draw your sample.

That's very different from my hospital's cg. We are to turn off whatever's running (30 min if TPN), then flush with 5 mL, aspirate 3-5 mL without disconnecting the syringe and discard that blood. Using a new syringe we draw the blood we need and then flush with 20 mL of NS followed by heparin (if ordered) and change the Q syte. Pushing the blood back and forth 2-3 times is unheard of to me.

moonshadeau, ADN, BSN, MSN, RN, APN, NP, CNS · May 28, 2009

30 minutes is an awfully long time to have the patient off of their TPN, at least in my perspective from the critical care setting. If this were the case with as many lab draws that occur in this setting the patient wouldn't be fed. Also, this method is effective if you are trying to conserve blood for pediatric or patients with frequent lab draws, because theoretically you shouldn't need a 10cc waste.

Here is one article that I quickly found on the practice.

http://findarticles.com/p/articles/mi_qa3689/is_200402/ai_n9385672/

iluvivt, BSN, RN · May 28, 2009

wating 30 min is way way to long and often drips can not be stopped that long without adverse effects to the patient.....considering the rapid rate of blood flow into the SVC.....one FULL minute is quite sufficient if you do it properly.......I also shut OFF everything going through it.....if using a multi-staggered tip design,optiamlly you should draw from the proximal lumen and TPN should be in the distal lumen...BUT if you just shut OFF everything and discard appopriate amount it really does not matter that much.....time the minute to make certain you actaully WAIT the FULL minute.......I have seen tons of policies and procedures and never have seen one more than 2 minutes. DO NOT accidently use the discard for the sample I have seen that happen a lot

blondy2061h, MSN, RN · May 28, 2009

Flush with saline, aspirate, push the blood back (repeat 2-3 times without disconnecting) and then draw your sample.
That's very different from my hospital's cg. We are to turn off whatever's running (30 min if TPN), then flush with 5 mL, aspirate 3-5 mL without disconnecting the syringe and discard that blood. Using a new syringe we draw the blood we need and then flush with 20 mL of NS followed by heparin (if ordered) and change the Q syte. Pushing the blood back and forth 2-3 times is unheard of to me.

Is this off a PICC, or a traditional central line? I would not think a 3-5ml waste would be sufficient for the later. We draw a 10 ml waste.

blondy2061h, MSN, RN · May 28, 2009

I agree with the posters saying 30 min is too long. We need an order to turn off TPN for any reason. Some of our patients get q2h blood draws. That'd be 6 hrs a day of their TPN being off.

chenoaspirit, ASN, RN · May 29, 2009

Ive never done the push-pull method one poster mentioned, actually Ive never heard of it. Ive always turned off the pump for one FULL minute, aspirate 10 ml and discard (from a different lumen if more than one), then with a new syringe pull off my sample, then flush. I cant imagine why you would wait 30 minutes, what does that accomplish? With bloodflow within the vein, one minute is sufficient. But honestly, every hospital should have a protocol on how to do this and it should be followed. Each of us on here may do it differently, but we all should be following our OWN hospital policy.