Auscultated Versus Palpated?

[AnthonyM83]

I know that an auscultated blood pressure is better than a palpated one. I'm just wondering if anyone has further info on HOW MUCH more accurate an auscultated BP is.

Thinking about it, it almost seems like a palpated would give a more accurate systolic since you might miss the initial beat sound if it's too low volume, less-than-stellar-hearing (like what I have thanks to the siren), or just if there's background noise.

But with palpation, unless you're in a bumpy ambulance, you're not really going to miss the pressure against your fingers from first beat of the pulse coming back.

Now, I assume the answer is that that the systolic pressure is different when auscultated versus palpated, even if done perfectly. But how different?

(BTW, I noticed a number of new hires placing the stethoscope heads, still over the brachial, but almost halfway up the arm and under the cuff. They get decent BP's and it's the way they're being taught. Anyone else do it that way? I was taught to basically put it almost over the AC right over the point where you can feel a pulse.)

[Mastabattas]

I was taught to find the pulse in the brachial and trace it towards the AC, then place my bell between the AC and about 1/3 up the arm on the path I had traced. I've watched others place it directly on or near the AC and wondered... tried it myself and I found it to be bit less accurate / harder to hear.

[spenac]

I have found that palpation tends to get me a systolic 5 to 20 lower than by auscultation. Because of this at times it is advisable on long transport to stop the ambulance to confirm BP. You may want to invest in an electronic stethoscope if you have hearing loss.

[kristo]

What I was taught was to listen in the middle of the brachial area. This was, of course, long before I knew there was something called the brachial artery, let alone that it crossed an area called the "cubital fossa" in a characteristic place.

Now, off the top of my head, the difference between the palpated and auscultated systolic blood pressure might simply be due to different indicators being used. When you auscultate, you hear when the pressure in the artery is enough to push blood through during systole, but create a very turbulent flow, hitting the wall of the artery. When you stop hearing the sound, that means that even pressure during diastole is enough to push blood in the artery, and the flow is no longer turbulent.

When you palpate, you are checking for the presence of a palpable pulsation. The appearance of turbulent flow just distal to the constriction (i.e. the BP cuff) and the appearance of a palpable pulsation of blood, say, in the radial artery, will probably not be at the same point.

[mobey]

I always palpate the artery prior to inflating the cuff, then I know I am in the right spot with my stethoscope.

I was taught when you palpate a BP always add 10 to the systolic.

[captainstandup]

Diastolic pressure is very important in cardiac patients and those suspected of having stroke. As you are aware the disatolic number is at least partially representative of just how well the heart is resting. In trauma patients, pulse pressure is very important as an early indicator of tamponade.

[firedoc5]

Sometimes I think it's beneficial to do both, especially if there seems to be a descrepancy with either one.

Something that I've heard time and time again that makes me just shake my head is to hear someone give a palpation BP with a diastolic reading.