BP arm VS calf while running pressors

[anarchy187]

I had a recent pt that I had running on a vasopressor over days while getting pressures using the arm as my reference. Then the night shift nurse uses the calf pressure and states "It gave me higher pressure so I stopped the vasopressors." During my shift I changed the cuff back to the arm when the pressure was around 90 on the leg, and then when measured 76 on the L arm and 68 on R arm. I talked to my charge and the docter and they said continue the pressors, but make sure it checks out on a manual cuff (which it did). When the new nurse comes back on shift they chew me out, saying it doesn't matter that the arm is lower the leg is higher. And says this in front of other coworkers and makes me look like a moron. Do you think I was right? As a reference here is the AACNs opinion on noninvasive BP monitoring. http://www.aacn.org/WD/Practice/Docs/PracticeAlerts/NIBP%20Monitoring%2004-2010%20final.pdf Tell me what you think!

[BelgianRN]

In my humble opinion BP-cuffs are primarily designed for upper arms and can be adjusted to different sites but my gut tells me this is less reliable in absolute values and should be used as a trend.

I read the AACN guideline and it clearly states that if you want to measure a BP on a different place you need to have the limb at heart height. This in practice would mean if you want a BP in the leg your patient would have to be fully supine or even slightly in Trendelenburg to achieve this. This would also mean some auto transfusion from the lower limbs to the central circulation with possibly increased BP as a result. If the BP was measured in a semi recumbent position the BP measured in the legs would be higher due to the measurement point being below the reference point.

So either it was measured in the correct position but subsequently the patient was changed back to the standard position HOB 30 - 45° so BP would probably be lower in comparison to the supine measurements. Or the patient would be measured in the standard position resulting in higher, but false BP.

I quote from the AACN guidelines:

Calf BP measurement is also referred to as an ankle BP. If a stethoscope is used, Korotkoff’s sounds are auscultated

over either the dorsalis pedis, or the posterior tibial artery (for calf BP), or the popliteal artery (for thigh BP). Results of

comparisons of automatic, noninvasive upper arm and calf BPs in adults vary. Overall systolic BP measurements

were higher in the calf than the arm in patients undergoing surgery, colonoscopy, and caesarean delivery under spinal

anesthesia.22-4 Differences in mean BP and diastolic BP were not consistent. Large differences for some individuals

make it difficult to devise a predictive formula that would be applicable in all situations.23In adults, calf BPs should be

used only if the upper arm is not accessible22 or if the appropriate size cuff is not available.

So I'd recommend using only the upper arms for BP measurements. But in my professional opinion patients receiving vasopressor(s) should also be outfitted with an art line for optimal monitoring and management since the waveform gives a ton of information.

[Nursetastic]

A patient is on pressors for days and doesn't have an art line? Why? I pressure the MD's for art lines as soon as a pressor is indicatede and usually win! Otherwise, I use the upper arm unless contraindicated by fistulas, grafts, DVT's, PICC lines, mastectomies, etc as mentioned in the article.

[sapphire18]

Our pts on pressors never have a lines. Bugs the **** out of me. We rarely use the thigh/calf for BPs but will often use the forearm. IME though, the upper arm is usually most accurate.

[K+MgSO4, BSN]

just curious as to why she was using the calf? if there was no contra-indication to using the arm why go there?

[GoldenFire5]

How was the urine output? Did it drop off when the night shift nurse put the cuff on the leg and stopped the pressors?

[07302003, ASN, RN]

I can't believe that the docs didn't insert an a-line. If a patient is unstable enough to need pressors, they need an a-line! Is there a reason they didn't place one?

[anarchy187]

Pt stayed with the BP on the leg for 4 days while I was gone. The Pt is now in MODS and UO is 0... The pressure was stupid low the entire time while the leg read great...

[detroitdano]

Why aren't you guys asking for arterial lines in these people? Anyone on pressors for longer than a few minutes needs an arterial line.

Have fun defending that one in court in a few years.

[blucrna]

I agree. I would have pushed for an art line. It's in the best interest of the patient and provides you with up to the moment bps for titration

[Melina]

A calf BP can be significantly higher due to calcification of the lower extremity arteries. We see this all the time when taking ABIs for wound assessment. I would be hesitant to to use this to take a patient off pressors. I'm interested as well to hear why there was no a-line.

[ozarkmomma]

A couple things to add... the bp in the lower ext will depend on other health issues like PVD. Ive used that to adjust pressors in a pinch, but its not optimal. Ca or renal failure keep you from using the upper ext. A Lines are not always available, nor do the Drs always want them in... so you work with what you have. I say know your pt. If you get a higher bp in the lower ext, there is something wrong with that, and its not a good number to titrate by.