arterial vs capillary glucose sample and a disagreement @ work

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Specializes in Ortho, Case Management, blabla.

I had a patient that had a PICC line. I did a PICC blood draw for the lab person. After the draw, a CNA ask me to put a dot of blood on the glucose meter. I told them no, and that they needed to poke the patient and get a capillary sample. They got really annoyed and call me "weird."

I've seen a CNA that will trail the lab person around and obtain blood samples as they are drawn venously. Even though it's not the hospital policy to obtain samples for glucose that way.

One of the other RNs rationalized it for me and said, "it causes less trauma to the patient because you don't have to poke them, but whatever."

Am I being too "by the book?" I was really tired and had a really stressful night, and I didn't really want to think about it very much, but my instinct and feeling was just not to do it. I don't want to be inflexible, but at the same time I want to ensure the best care I can give. I know there is a difference in the glucose levels between an arterial and capillary sample but I'm not sure exactly how much the difference can be. I haven't found any reliable source of information about it. The books just all say there is a difference. I guess the arterial sample would be more accurate, but at the same time if the person had always regulated their insulin dose via fingersticks, wouldn't you want to keep it the same?

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Specializes in Orthopedics/Med-Surg, LDRP.

Since when is a Picc line an arterial line? It's a central VENOUS line. Arterial lines are typically in the jugular in the neck. You could have given the tech a dot out of the PICC. Venous blood and arterial blood are very different looking. Venous blood has that darker red to it and arterial is more like firetruck red. It's bright.

I, personally, have never had a person have an arterial picc line.

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Specializes in ER, ICU, Infusion, peds, informatics.

it depends on the meter.

some have only been tested with capillary blood (finger sticks).

some can be used with capillary, venous, or arterial whole blood.

some can even use spun serum.

it all just depends on what the manufacturer recomends; and, of course, what your hospital policy is.

when i was a nursing student, the blood had to be from fingersticks.

about five years ago, we started using meters that could use any type of whole blood or serum. policies changed to reflect this.

i would use the blood from the picc, but that is ok with my hospital policy.

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Specializes in Ortho, Case Management, blabla.
Since when is a Picc line an arterial line? It's a central VENOUS line. Arterial lines are typically in the jugular in the neck. You could have given the tech a dot out of the PICC. Venous blood and arterial blood are very different looking. Venous blood has that darker red to it and arterial is more like firetruck red. It's bright.

I, personally, have never had a person have an arterial picc line.

Replace any mention of the word arterial and put venous, because that's what I meant. I've barely gotten any sleep yet today (holiday) and I'm feeling a bit out of it. I've got arteries on the brain I guess.

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Specializes in Orthopedics/Med-Surg, LDRP.
Replace any mention of the word arterial and put venous, because that's what I meant. I've barely gotten any sleep yet today (holiday) and I'm feeling a bit out of it. I've got arteries on the brain I guess.

LOL, it's ok. I've used picc blood for accu check blood. Then again a lot of times I'm pulling BMP/CMP's out and the glucose is checked then, so sometimes I won't do double testing if I know I'll get the results back before change of shift.

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Specializes in Ortho, Case Management, blabla.

I just found the instruction manual online for the glucose meter we use and it says it can accept any type of sample. I need to check exactly what the hospital policy states about that stuff. I know what I was told about it, but I don't remember exactly what it says (agh orientation and too much stuff getting thrown at me at the time). I'm willing to bet the person who explained it to me about the venous draws might have been wrong if our glucose meters can accept any type of sample. I've just never really run across this before. I feel like a dummy.

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Specializes in NICU, PICU, PCVICU and peds oncology.

There have been a number of studies that have demonstrated that glucose meter blood sugars obtained using central blood (either arterial or venous) are much closer to the results the lab will give you on samples sent to them than those obtained by capillary sampling. 99% of the blood sugar measurements we do in our unit involve central blood as opposed to capillary blood. So if your hospital policy approves, don't subject the poor patient to unnecessary fingersticks.

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Specializes in Med/Surg.

In the past, when a patient needing a morning blood sugar also had AM labs ordered, night-shift techs on my unit would wait to get a sample of blood from the lab person when they made rounds or, if the patient had a PICC, from the RN when they did their blood draws. This way the patient would only be stuck and only woken up once. I think they still allow this, but can't say for sure.

Another common practice definetly not allowed anymore involved patients who were receiving a dialysis treatment. In the past, if a CNA had to check a blood sugar, they could bypass poking the patient and instead ask the dialysis tech to obtain a sample of the patient's blood(from one of the catheters hooked up to the patient, I think??). I'm not 100% sure why it's not allowed anymore, but I think it has something to do with results not being as accurrate and also because it is not safe for the patient.

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Specializes in Cardiac Telemetry, ED.
Since when is a Picc line an arterial line? It's a central VENOUS line. Arterial lines are typically in the jugular in the neck. You could have given the tech a dot out of the PICC. Venous blood and arterial blood are very different looking. Venous blood has that darker red to it and arterial is more like firetruck red. It's bright.

I, personally, have never had a person have an arterial picc line.

A jugular line is also venous.

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Specializes in NICU, PICU, PCVICU and peds oncology.

In my 10+ years of ICU nursing I've never had a patient with an arterial neck line... unless it was an ECMO cannula. We do use radial, ulnar, brachial, femoral, posterior tibialis and dorsalis pedis arteries though, most commonly the radial or femoral. Losing circulation to a limb is one thing. Losing it to your head is quite another.

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Specializes in Orthopedics/Med-Surg, LDRP.

I just had a guy with a triple lumen arterial in the right carotid. He ripped it out in a confused state, lost a lot of blood and nearly coded. It happens and it happened in ICU right before his transfer here (ortho/neuro, step-down unit).

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Check out the journal published by AACN. They recently published a study regarding this very thing. Evidence Based Practice.

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