Question about some labs

[november17, ASN, RN]

I guess this can be kind of a case study, if you will.

A coworker of mine was taking care of a patient (we'll call her Mrs. X). Mrs. X is day of surgery from some type of joint arthroplasty. Estimated blood loss

Mrs. X has no medical history whatsoever besides severe arthritis. Bone on bone, etc etc.

Mrs. X is lying in bed receiving D5NS0.9 @ 125 CC per hour through a 20ga IV on the dorsal side of her left hand.

The phlebotomist showed up to draw a CBC/Chem7/INR/PT...the standard stuff.

About 15 minutes after the phlebotomist left, the lab called and said Mrs. X had several critical lab values.

WBC 2.3

HGB 5.1

Glucose 821

And some others...I can't remember offhand. Those were the biggies.

Upon assessment, Mrs. X is lying in bed. Cap refill

My coworker is at this point flipping out because the glucose is 821. She pages the physician. Physician went monkey over the phone, but ordered a stat redraw. In the meantime, my coworker is prepping to send this patient to the ICU. Physician is freaking out whereever he is, and is calling for updates every 2 minutes.

Between the time the phlebotomist left and the time the original labs were phoned to us, Mrs. X had gotten up and walked 10' to the bathroom and back with a walker and a stand-by assist.

10 minutes later, All the labs came back normal.

Complete fluke with the labs?

The original lab was drawn in the AC area, in the same arm that the IV was infusing. The second lab draw was taken from the other arm where the IV wasn't infusing. I said, "Well, what probably happened was that the D5NS was simultaneously boosting the sugar and diluting the rest of the blood." None of my coworkers took my theory seriously. Even one of the "seasoned" nurses said, "no that's ridiculous, they probably got the vial mixed up with someone elses somewhere else in the hospital!!"

Now, I'm no chemistry/lab expert, but I don't think my theory is far off. I had an asymptomatic patient with an HGB of 6.5 one time and the physician suggested it was a diluted sample and a redraw (the physician was wrong in that case, but that's besides the point). I was just wondering if anyone has run into this type of thing before. Is it conceivable that dextrose would show up as glucose in a lab test? They're very similar chemically. Maybe someone with more chemistry experience can either back me up or refute my theory?

ps:No one was freaking out except the nurse that had the patient, we were all kind of "meh" after we realized the patient was completely asymptomatic.

[TazziRN, RN]

Depends on where the IV was. If the draw was in the AC but the IV is infusing in the hand, then you're probably right on. This is the reason why labs are never drawn proximal to the IV.

[november17, ASN, RN]

Depends on where the IV was. If the draw was in the AC but the IV is infusing in the hand, then you're probably right on. This is the reason why labs are never drawn proximal to the IV.

I'm glad I'm not crazy.

[TRAMA1RN]

Labs are never to be drawn proximal to IV site unless of course it is a lock and has not been used for infusion with 20 minutes of lab draw. I thought everyone knew that, especially the lab techs.

Good job in your assessment, and remember labs and equipment are not always infallible, it is very important to always look at the patient.

Again good job!

[november17, ASN, RN]

Good job in your assessment, and remember labs and equipment are not always infallible, it is very important to always look at the patient.

!

It wasn't my assessment, it was hers. I was just saying, "Hey, relax, it's probably just the IV fluids screwing the labs up." My coworker was about to have a conniption fit.

[PyshRN]

This happens sometimes on our floor when people forget to turn off their IV when drawing from a line. Usually, the lab calls us if the results look odd.

Our techs actually ask us to stop IV's if they need to draw on an arm that has an IV infusing (if it is allowed to be stopped for a short time). We get a lot of patients with poor veins and they sometimes have to stick them in an undesireable location.

[EmmaG, RN]

It wasn't my assessment, it was hers. I was just saying, "Hey, relax, it's probably just the IV fluids screwing the labs up." My coworker was about to have a conniption fit.

You were right, they were wrong

[november17, ASN, RN]

You were right, they were wrong

btw I'm going to print this thread out and put it in her mailbox heheheh (jk about the putting it in the mailbox thing, she reads this board and knows who she is!!!).....I TRIED TO TELL HER!!!

seriously, would dextrose show up as glucose? there's gotta be some chemistry/lab people out there that can confirm or deny this.

[elizabells, BSN, RN]

I've seen it with D5 running through an art line used for labs, and the "waste" blood drawn first gets mixed up with the sample. You get rock-bottom crits and electrolytes and sky-high glucoses... although the glucose is always high in that case, as it clings to the line and contaminates the sample. So yes, the dextrose in IVF will give you a wonky glucose result, is what I'm saying.

[EmmaG, RN]

seriously, would dextrose show up as glucose? there's gotta be some chemistry/lab people out there that can confirm or deny this.

Yes. It will alter glucose readings. Do an accucheck on a drop of D5 if you want to check it out

[november17, ASN, RN]

Yes. It will alter glucose readings. Do an accucheck on a drop of D5 if you want to check it out

I'd hate to waste hospital resources, so I'll take your word for it :redbeathe

[MikeyJ, RN]

btw I'm going to print this thread out and put it in her mailbox heheheh (jk about the putting it in the mailbox thing, she reads this board and knows who she is!!!).....I TRIED TO TELL HER!!!

seriously, would dextrose show up as glucose? there's gotta be some chemistry/lab people out there that can confirm or deny this.

Not sure about the glucose showing up in the lab -- but I wonder if the patient was any type of steroid for their arthritis, as steroids can increase the glucose a significant amount.