Cuff occlusion test

[deleted875186]

---

Members don't see this ad.

Recently had ICU patient with a BP target for neurosurgery, on vasopressors to keep BP high. Long story short, using radial art line to titrate pressers for BP target, and primary team comes by and does a “cuff occlusion test” and states the NIBP is closer to the actual systolic BP then the art line. Wants to use NIBP to measure pressure instead. Thoughts?

It was a good art waveform as well. This cuff occlusion test involves placing a manual cuff on the arm with the art line, inflate to abolish the waveform, then release pressure until you see a small wave, which apparently represents the true systolic pressure.

 

[NICMAN]

He is full of crap. Ask him why he is relying on a surrogate measure when you can directly measure the intraarterial blood pressure.

 

[nimbus]

When neurosurgery asked for a particular target blood pressure, was it based on studies using cuff occlusion test BP or Aline BP? I doubt it’s based on cuff occlusion test since nobody actually does that.

And since cuff width affects cuff occlusion pressure, what cuff width do they consider standard?

They pulled it out of their *ss.

 

[Mman]

aren't neurosurgeons usually concerned with the MAP and not the systolic pressure?

 

[drmwvr]

Well just use a bp cuff during the surgery too.

 

[Psai]

Keeping the bp higher with pressors does not have great evidence as it is. I figured bp cuffs are more accurate for maps. I trust arterial lines more for the actual systolic and diastolic. Then again blood pressure is itself is a surrogate for perfusion which is what we care about but can't measure well.

Cuff occlusion sounds like bs.

 

[vector2]

aren't neurosurgeons usually concerned with the MAP and not the systolic pressure?

Depends on if we're talking about spinal cord perfusion s/p SCI or ICH 2/2 hemorrhagic stroke etc etc

 

[shepardsun]

I figured bp cuffs are more accurate for maps. I trust arterial lines more for the actual systolic and diastolic.]

I don't really get this. If you know the systolic and diastolic, you know the map. The BP cuff measures the MAP and then uses an algorithm to generate SBP and DBP, so in theory there are infinite pressures that could get you the same MAP. But the intrarterial catheter is the real deal

 

[Mman]

I don't really get this. If you know the systolic and diastolic, you know the map. The BP cuff measures the MAP and then uses an algorithm to generate SBP and DBP, so in theory there are infinite pressures that could get you the same MAP. But the intrarterial catheter is the real deal

I always like it when the cuff says the pressure is 115/105 and the nurse wants to know how I'd like to treat the pressure. I let them know I'd like to figure out the actual blood pressure before doing something about it because I'm pretty sure their pulse pressure isn't 10.

 

[fakin' the funk]

I always like it when the cuff says the pressure is 115/105 and the nurse wants to know how I'd like to treat the pressure. I let them know I'd like to figure out the actual blood pressure before doing something about it because I'm pretty sure their pulse pressure isn't 10.

This is a daily discussion point on ICU rounds, sometimes, multiple times a day. No, 130/110 isn't a real blood pressure.

 

[deleted875186]

Depends on if we're talking about spinal cord perfusion s/p SCI or ICH 2/2 hemorrhagic stroke etc etc

Yes, it was hypertension for vasospasm associated with ICH. They tend to give systolic BP goals in these cases, not sure why instead of MAP goals.

 

[deleted162650]

Maybe they were concerned about "whip" (underdamping) in the A-line pressure reading???

 

[dchz]

I totally agree with others that A line is usually way more accurate than the NIBP.

However, as @SaltyDog said, underdamping and overdamping are real things (he's not trolling this time). So you need to know what in your line is under/over damping. E.g. Vamps under damp, roses over damp.

What i really don't understand is that the nurses under damp with the vamp and then over damps with the rose and correlates it to the NIBP.... that is a real brain teaser.

 

[nimbus]

It was a good art waveform as well. This cuff occlusion test involves placing a manual cuff on the arm with the art line, inflate to abolish the waveform, then release pressure until you see a small wave, which apparently represents the true systolic pressure.

Maybe they were concerned about "whip" (underdamping) in the A-line pressure reading???

They’re still using the Aline. Makes no sense to me. And again cuff width affects when you would see a pulse on the Aline. Wider cuff will give a lower pressure than a narrow cuff.

 

[vector2]

Yes, it was hypertension for vasospasm associated with ICH. They tend to give systolic BP goals in these cases, not sure why instead of MAP goals.

Vasospasm 2/2 ICH is one of those rarer situations where the literature may talk about SBP in relation to preventing rebleeding and MAP in relation to maintaining cerebral perfusion pressure. Sometimes nsrgy will give some absurd hemodynamic goal which may be impossible to achieve (map > 80-85 AND SBP < 140). Most of the time though, these situations happen with aneurysms. In those cases SBP takes precedence before the aneurysm is secured and then the pt can be pressed to a higher MAP with more permissive SBP after it's secured.


In regard to the cuff occlusion test, it actually is the best initial test of the damping. The first systolic spike on the Aline when letting the cuff down is the true SBP. That being said, the MAP should still be pretty accurate regardless of damping.

 

[Shimmy8]

So what do y’all do when a surgeon requests SBP <160 or something post op and a-line reads like 210/75 and NIBP 155/80 with similar means?

In my heavy vasculopath population that over-shooting systolic is real (IMO).

 

[vector2]

So what do y’all do when a surgeon requests SBP <160 or something post op and a-line reads like 210/75 and NIBP 155/80 with similar means?

In my heavy vasculopath population that over-shooting systolic is real (IMO).

If I'm actually worried about bleeding as well then I'll bring the a-line sbp down to 160. We know from various vascular surgery observational studies going back 30 years that postoperative hypertension is associated with increased rates of rebleeding. My guess is that the aortic impulse and the associated shear stress during systole contributes to "popping the clot"

 

[deleted59964]

So what do y’all do when a surgeon requests SBP <160 or something post op and a-line reads like 210/75 and NIBP 155/80 with similar means?

In my heavy vasculopath population that over-shooting systolic is real (IMO).

Pull out the art line

 

[dannyboy1]

Give them whatever number they want and move on. Not worth your time and aggravation

 

[narcusprince]

So theoretically an arterial line can exaggerate the systolic and diastolic blood pressure if its underdampened. A simple flush test can determine dampening. MAP is determined on an arterial like by the area under the curve. Titrating a Systolic Blood pressuee seems pointless when vessels see map. Likely the maps correlated between the aline and bp cuff. Cpp is defined as map - icp. Test the aline if its underdampened try to correct it(ensure proper setup) it if u cant use the bp cuff.

 

[vector2]

So theoretically an arterial line can exaggerate the systolic and diastolic blood pressure if its underdampened. A simple flush test can determine dampening. MAP is determined on an arterial like by the area under the curve. Titrating a Systolic Blood pressuee seems pointless when vessels see map. Likely the maps correlated between the aline and bp cuff. Cpp is defined as map - icp. Test the aline if its underdampened try to correct it(ensure proper setup) it if u cant use the bp cuff.

There are definitely situations where vessels "see" SBP. Aortic dissections propagate due to shear stress from the systolic impulse. It's reasonable to treat the SBP for these pts or situations like aortic cannulation for CPB.

 

[anbuitachi]

I dont think it's that crazy to be honest. I've done it in the PACU for patients with tight blood pressure controls, and the Arterial line and NIBP pressure varies widely. Though i usually do a square wave test to see if theres any over/under dampening but occasionally if they happen to be on the same arm may see where arterial line starts to show up with NIBP deflating to get an idea of blood pressure.

 

[deleted50478]

Recently had ICU patient with a BP target for neurosurgery, on vasopressors to keep BP high. Long story short, using radial art line to titrate pressers for BP target, and primary team comes by and does a “cuff occlusion test” and states the NIBP is closer to the actual systolic BP then the art line. Wants to use NIBP to measure pressure instead. Thoughts?

It was a good art waveform as well. This cuff occlusion test involves placing a manual cuff on the arm with the art line, inflate to abolish the waveform, then release pressure until you see a small wave, which apparently represents the true systolic pressure.

How to Use Than vs. then Correctly – Grammarist