NBP cuffs...?mis-used in ICU....

rn91 · Sep 30, 2005

Hey Y'all
I hope y'all don't mind if I drop into your "virtual OR" for a minute. I've got a question thats been bugging me and thought you-guys had some of the highest quality exchanges on the forum. (A little flattery to ease my way in...)
I've observed that the CRITICON NBP cuffs that are virtually universal in this area are frequently mis-used. I think. By that I mean--I find 'em 'up-side-down' (the 'artery' arrow proximal) and in strange locations (around the ankle) and of the wrong size (leg cuffs wrapped around a perfectly normal sized upper arm).
Many of these folks are getting drips for their BPs--Tridil, Neo, Dopamine. And pretty often when I 'correct' the NBP Cuff I can (natually) rapidly wean the drugs. So I am morally certain that the prev ICU nurse was ignorant/negligent in the basic matter of measuring the BP. But I have no way to prove it, so have not said anything.
Would love to suggest that some instruction and policy/procedures be given about this but a google-search today yielded nothing (except a chance to EMail GE Healthcare--who bought CRITICON out, it seems--which I did).
Any feedback from y'all? Any manuals from manufacturer or excerpts from your policy books? Just advice or experiences?
Sure 'preciate ya
Papaw John

Any patient receiving IV pressers should have some type of invasive line to monitor them e.g. A-line. That should be the question asked for the hospital.

JustMe · Oct 5, 2005

There are some scholarly papers out there concerning the accuracy of automatic BP cuffs, using them on different extremeties or positions, how they correlate with A-lines and/or auscultation. I've read one or two myself because I have an inherent distrust of BP cuffs due to their tendency to give readings all over the place on the pts. you need it most. One thing that I gathered from the papers and from personal experience is that even though the systolic/diastolic does not always correlate, the MAPs oftentimes do correspond (when comparing BP cuff and A-line). But really, you should be able to find a couple good papers without much problem that would be better able to answer those questions.

You are correct about the MAP. My understanding of BP readings from automatic cuffs is that the MAP is correct and the systolic/diastolic are "calculated" from that reading. The best rule of thumb when titrating drips with NBPs is look at the patient. If the patient is warm, pink, dry and alert the BP of 80 systolic probably doesn't need the drip increased. There are a number of physical and physiological factors that can give inaccurate readings, i.e. a bent arm during the deflation. At best a NBP is a guesstimate, a reading at one particular place in time. BPs should be looked at as a trend unless your patient is cool, pale, diaphoretic and confused.

papawjohn · Oct 5, 2005

Hey JustMe

You know that's something I shoulda thought of--sometimes when the machine cycles and the Pts arm is in a bad position or waving around--the reading comes up like: XX/XX-55. (With the 55 being the MAP of course.)

Don't know why that eluded me til you suggested it.

As to titrating gtts by using only the numbers--you are of course correct. Palpable pulses, urine output, skin tone & temp, mentation--all have to be taken into account. That's why you'll never see a computer-link between the Art-Line or NBP and the Dopamine pump (no matter how bad the nursing shortage gets.)

Feeling job-secure...

Papaw John

Tenesma · Oct 6, 2005

papawjohn...

1) BP cuffs: it does not matter which way the cuff is applied (right side up or upside down... inside out is a lot harder though)

2) Placement: it doesn't matter where the BP cuff goes - even though systolic and diastolic are different at the calf and the upper arm, the MAP is the same... however, the BP cuff won't register much in the lower leg if the patient has significant peripheral arterial disease or diabetes with glycosylation of the arteries or anybody who has significant calcification of those arteries

3) I suggest you learn how a BP cuff works and the different kinds out there... before you call your colleague nurses negligent or ignorant.

papawjohn · Oct 6, 2005

Hey Tenesma

Really!!! I am willing to be wrong about this issue!!!!!

It does seem to me that when I place the NBP cuff in the position that would have given me a PASSING GRADE in nursingschool (which I was glad to get a passing grade!!) that the dopamine is INSTANTLY weaned.

But in the large scheme of things, I'm not a smart-a-- and would just like to understand these NBP things.

And 'inside-out'----tooo funny. I'll have to try that when I'm back at work next week.

All in good fun/spirit of honest inquiry...

But perhaps you are among the group of nurses who thinks that any skeptism of numbers as they appear on the monitor is just 'really really stupid'. Well, I have heard that. And I think YOU have to defend your reliance on the NBP more than I have to defend my sceptism of the NBP. Just an old fart, of course. Soon to be retired. So our Pt's will be all yours. You feel ready for that?

Edit----

I have to admit---I'm turning 60yrs old this year---that there is a large group of young nurses out there that seem to think that if a number appears on the cathode ray tube---THAT NUMBER IS THE WORD OF GOD. As if it had appeared in burning bushes and with thunder and lightning and the pharoh's sons dead---and I doubt it until I see the rest of the Pt's status. But I'm a skeptical person.

P- J-

Papaw John

jwk · Oct 6, 2005

But perhaps you are among the group of nurses ....

and perhaps not...:rotfl:

papawjohn · Oct 6, 2005

Hey Jwk

I'm not so smart I know all the answers--(that NBP cuffs are not the real bp and that all the ins- and outs- and ups- and downs- of their use should help us (who actually, in the real world, have to titrate Nitro or dopamine or Neosynephine) without perfect monitoring of MAP as by--for instance by

art lines.)

OK---Help me out. What do YOU KNOW about the accuracy of NBPs. I

'd appreciate specific refs. Do you have websites? Other refs?

You sound very smart. YOU tell me what I should do in the middle of the night with a BP somewhere between 120/50 and 70/30. That

bp is NBP.

You're so g**d**m smart. Tell me what I should do. Just you and me. Just a very sick person, just a surgeon who doesn't answer the phone, what are we gonna do?

Papaw John

No A line, no BS.

Just you and me at the bedside. OK?

BigDave · Oct 6, 2005

Cool down cowboy...

I think jwk was just in jest about tenesma's nursing skills (since neither one of them is a nurse).

Actually tenesma is corrrect. How you place the cuff on an automatic bp cuff is not important, but the size is. In the periphery, SBP tends to increase, DBP goes down, but the mean is about the same (pathology absent).

The systolic is a measured value (start of oscillations). The mean is the measured value of highest amplitude (but is a calculated value on some devices). DBP is either measured or calculated (depending on equipment).

Conditions such as a-fib or freq pvcs can make readings inaccurate,

Yes, an art line is preferred. They usually work great in the OR or when new, but we all have cussed at them in the ICU.

References:

Dorsch & Dorsch, chap 24

Morgan & Mikhail, chap 6

Davis & Parbrook, chap 17