blood cultures

[Nurse_AV]

When a physician/practitioner orders blood cultures on a patient who has a central line and an arterial line, do you draw one set from the central and one from the art line? I ask because I am a new ICU nurse (have been a nurse for over 8 years total but just started in critical care a few weeks ago). I have worked in this hospital for over a year and I was taught before that only ONE specimen should come from central/PICC line and not both due to the high risk of contamination of the line. My preceptor disagrees and we drew cultures from a PICC and the second from the art line. Also, I was told not to flush/waste 10mL when doing blood cultures and just to aspirate blood immediately and use that as the specimen. Is this because the flush could wash away potential bloodborne contaminants? My preceptor has been great but she really wasn't sure on both of these questions. Thanks in advance for any help with this!

[Twinmom06, ASN, APN]

the only time I've heard of cultures coming from a central line is if the line is the suspected source of infection, otherwise I've seen them drawn perpherially

[britpanda]

the only time I've heard of cultures coming from a central line is if the line is the suspected source of infection, otherwise I've seen them drawn perpherially

Same here.

I'm not sure as to why you wouldn't flush and nothing would be wasted prior to the specimen collection though, although I agree with your speculation regarding accuracy of specimen. Whenever we draw from a central line in the facility where I work it is policy to flush with 10mL NS then withdraw and waste 5-10mL.

[ArmaniX, MSN, APRN]

Our hospital has rolled out this new policy. All blood cultures are to be done by two peripheral sticks. We are not allowed to use the central line or arterial line. If unable to obtain cultures we can draw from those two sources only with an MD order.

It seems to me that this is a way to falsly lower CLABSI rates. But who am I to say...

[Here.I.Stand, BSN, RN]

Our policy is to draw all cultures peripherally

[AJJKRN]

At my hospital, blood cultures would be drawn in "quants" via peripheral and out of each lumen from a central line if the Pt has one at the time of suspected infection. When drawing from the lines, it's my facility's practice to not flush first and you only pull back exactly so many cc's and nothing can run through the lumen for at least 30 min prior to collection. I do think the reasoning to not flushing the line first is to not dilute/flush away any microbes, etc.

I would have to ask about a-lines but at my facility they are changed every four days just like IV's and are being continuously flushed anyways by either heparin or normal saline depending on the service covering the Pt (ICU vs Cardio-thoracic).

[jadelpn, LPN, EMT-B]

2 peripheral, 2 different sites. And check your policy. Blood cultures x2 for us means 4 actual bottles--2 from each site. This could be why it doesn't matter if drawing from actual lines if you have one that would have some heparin in it? (and I have not a clue, just thinking out loud). But we do all peripherally.

If you are doing just one bottle, and your lines have heparin--that could be the purpose for a draw and waste. But the integrity of the sample can be compromised if you are not using real aseptic technique between bottles.

If there is an infection, there's an infection. It would be treated the same based on sensitivity regardless of the source, but I can see the point if one of the lines is the source of the infection would that be a matter of removing and restarting at another site?

I am so not an ICU nurse, however, this is a great question!!

[Karou]

Can you look up your facilities policy? We only draw from a CL if they suspect that's the source of infection. Otherwise it's peripheral. If drawing from a CL, we don't waste. Not sure why, but that our written policy.

[Dranger]

We do:

1 set CVC

1 set periphreal

[CryssyD]

Check your policy--you could also just ask the MD what he/she wants.

I've always worked places that required peripheral and central line site collection; you are correct about not flushing the lines prior to collection--you don't want to wash any colonies away.

The peripheral site is the most important, though, I think--lines can get colonized, but that doesn't mean the patient has an active infection.

[Nurse_AV]

right! okay well it concerned me because in the orders for blood cultures it even states "preferred to avoid use of a central line whenever possible". my preceptor is an awesome nurse and has been in ICU for 10 years so i hate to question her, but it just seemed odd to me. at least one of them should be a stick i thought, but i would honestly prefer both of them - unless like britpanda said the suspected source of infection is the line itself. thanks for the replies.

[A&OxNone, MSN, RN]

My facility has (within the last two years) using the "waste" as the sample of a blood culture. So just like you said, hooking up the syringe and pulling back immediately. The purpose is just like you suggested - so it won't dilute any potential infection.

Also, some of our docs do a CVL and peripheral stick. Others just a CVL sample. I also work in peds so the sticks sometimes are minimized but I don't think it causes any problems not to get the peripheral stick.

My other question for the adult people that say they only get 2 peripheral sticks - if a patient has a CVL and develops a fever, wouldn't a line infection be one of the first potential sources so getting that sample would be better, right? Makes me think it's also to adjust the line infection rates, too.