BP Question

[MikeEMT]

I use a Litmann Select stethoscope and while I am pretty good at obtaining BP's I can always improve. Someone told me that the Diaphram on the Select picks up both High frequency and Low frequency sounds depending on how much pressure you apply.

That got me to thinking, are Korotkoff sounds considered high frequency or low frequency?

I normally get BP's without too much thought in what I am doing. Finding out about the Select Stethoscope though was eye opening because there were a couple of difficult ones that I couldn't obtain a BP on and had to use a dual head. I now think this was more to user error and how I was holding the diaphram on the patient rather than just not being able to hear.

[MariB]

Low, however the pressure frequency is great for breath sounds etc, I haven't noticed much when it came to blood pressures

.

Adding, but I have a totally different stethoscope. It is also a littmann

[BEorP]

I think that the more important thing that the stethoscope side of things is knowing the anatomy and putting the diaphragm/bell right over the artery rather than just sticking it somewhere in the antecubital fossa. I strongly suggest taking the time to palpate the brachial artery to get this exactly right (and I do do this myself), but if you're not going to do that then you should at least know where the brachial artery lies. It is more medial rather than in the centre where many people seem to stick their stethoscopes before complaining about how it was such a difficult BP to obtain.

[MikeEMT]

I think that the more important thing that the stethoscope side of things is knowing the anatomy and putting the diaphragm/bell right over the artery rather than just sticking it somewhere in the antecubital fossa. I strongly suggest taking the time to palpate the brachial artery to get this exactly right (and I do do this myself), but if you're not going to do that then you should at least know where the brachial artery lies. It is more medial rather than in the centre where many people seem to stick their stethoscopes before complaining about how it was such a difficult BP to obtain.

I am well aware of the anatomy and I too palpate the Brachial. However the patients that I had difficulty with were Bariatric patients and I wrongly assumed that pressing harder to get through the fat would make it easier to hear the BP. I was discussing this with a doctor because I was concerned about the difficulty I was having and he told me that my stethoscope had a tunable diaphram to pick up high and low frequencies. He had to take off before he could explain further.

If Korotkoff sounds are low frequency that would explain why pressing harder actually made it more difficult to hear. On one of the patients I was able to use a different stethoscope to hear - a dual head. I don't know what I did differently but I did something that made it so I could hear. The other patient I had to palpate the BP because I couldn't hear at all, I couldn't even palpate the Brachial.

It concerns me when I can't hear a BP which is why I asked this, because for those of us with tunable diaphrams knowing the frequency of the sounds were listening to effects how we hold the diaphram on the patient.

[island emt]

layers of fat dampen sounds and make pretty much all procedure more difficult. Your optimum choice is to place the diaphragm just firmly enough to be able to hear the low resonance sounds. background noise such as from the diesel engine make it that much harder to pick up the rumble your trying to hear.

[MariB]

layers of fat dampen sounds and make pretty much all procedure more difficult. Your optimum choice is to place the diaphragm just firmly enough to be able to hear the low resonance sounds. background noise such as from the diesel engine make it that much harder to pick up the rumble your trying to hear.

if they are in the ambulance, best to just palpate at that time.

Like I said, I have been firm with mine and light with mine, it hasn't made a difference with BP, only with breath sounds. If the bell is in the right place, the pressure isn't really going to matter for BP

[island emt]

I can hear just as well in the back of the truck wit a $30 sprague as with my wife's master cardio II Littman.

It's an acquired skill thats takes time to learn.

When you start releasing the air from the cuff, palpate at the wrist and listen at the same time.

It may be a right brain skill that only lefties can do though:::

[MariB]

I can hear just as well in the back of the truck wit a $30 sprague as with my wife's master cardio II Littman.

It's an acquired skill thats takes time to learn.

When you start releasing the air from the cuff, palpate at the wrist and listen at the same time.

It may be a right brain skill that only lefties can do though:::

Dang Lefty Show off

I can hear fine in most situations, but you get a loud whaaaaaabulance, and a crying patient, squawking radio, taking emts , I just palpate.

[MikeEMT]

I can hear just as well in the back of the truck wit a $30 sprague as with my wife's master cardio II Littman.

It's an acquired skill thats takes time to learn.

When you start releasing the air from the cuff, palpate at the wrist and listen at the same time.

It may be a right brain skill that only lefties can do though:::

I find the cheapo stethoscopes hard to hear with. However my Littmann which is the $50 model is a dream. It might just boil down to the Littmann fitting my ear better though. I have no need for a Cardiology stethoscope but a few of our EMT's have them. Personally I wouldn't waste my money on a $150 scope.

Dang Lefty Show off

I can hear fine in most situations, but you get a loud whaaaaaabulance, and a crying patient, squawking radio, taking emts , I just palpate.

I don't like to palpate and I rarely do it. Only time I palpate is if patient condition warrants it or if I cannot auscultate. In the ambulance I just isolate the arm. We have Mercedes Sprinters though and even though they are diesel they are not noisy. I can still auscultate even in our old Ford type II's that we use for spares.

[scubanurse]

Just curious, what is your reason for rarely palpating blood pressures?