UPDATE: The consensus definition of hypertension (i.e. the cutoff BP of defining hypertension) has changed since this video was posted. I'm not fully convinced by the evidence behind this change, but the updated definitions are summarized on a table here: www.heart.org/-/media/health-topics-images/hbp/blood-pressure-readings-chart-english.jpg?la=en
Hello, I satrt working finally as a graduated doctor tomorrow! And I wanted to thank you because you literally helped me to pass all my internal exams in the university! And I will continue watching your videos!❤❤
The threshold, as I learned from watching "John Q", for systolic blood pressure that leads to dangerous hypotension, is this ---- The optimal systolic BP to maintain health is 80 or more if it is low, but anything under 80 is a warning sign. A systolic BP of under 70 is a medical emergency and has to be resolved by raising systolic BP to 70 or more ASAP. Failure to keep that pressure at 70 or above at that point can lead to serious complications - one of which is fatal heart failure.
The video incorrectly identifies the reason for the Korotkoff sounds. These sounds are due to the turbulence of the blood as it moves through the partially obstructed artery. The artery does NOT alternate between compressed and open. Can you fix this error? Otherwise it is an excellent explanation on how to correctly take blood pressure measurements..
Thanks for the comment. My primary audience for this video was first year medical and nursing students, so didn't want to get too into the details of the mechanism of Korotkoff sounds, but probably could have been more explicit that the precise mechanism of their generation is amazingly still not known for certain. Regarding whether the sounds are from alterations between relatively compressed and open states, or from turbulent flow through a partially obstructed artery that's relatively static, papers have been published providing support for both views. The most recent entry into the literature on this topic is one that puts forth a model similar to the former (which the author has called the "wall resonance hypothesis"). The author posits that the sounds are caused by the arterial walls "ringing at a natural resonant frequency determined by the elasticity and dimensions of the artery wall and the mass of outward moving tissue" caused by the transition between the artery being in a buckled state (i.e. arterial pressure below cuff pressure) and an expanded state (i.e. arterial pressure above cuff pressure). docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1064&context=bmepubs (Disclaimer: I am not an engineer, so cannot vouch for the accuracy of his work.) But I should have been more clear about the uncertainty.
Is there substantial difference between different manual sphygmomanometers? I want to purchase a professional grade one but don't know which to choose...is there an industry standard that I should look for? Thanks!
Mercury sphygmomanometers were considered to be the gold standard for most of the last century, and are probably still the most accurate of the manual devices. However, concerns over the toxicity of mercury have led to these falling out of favor, and it would be pretty unusual for an individual clinician to own one. Among the aneroid sphygmomanometers (any BP measuring device with a round gauge and a needle - like the one in the video), I don't know of any consensus as to which style and/or brand is best. Aneroid devices are fragile however, and just a single drop on to a hard surface can render one ruined beyond repair. Also, from an N of 1, I purchased a relatively cheap one branded with an American drug store chain for casual/non-official use, and it "broke" (i.e. no longer zeroed) after just a few uses spread out over 6 months. So I would not recommend going with the cheapest one you could find...
I have a few really annoying set of patients where after i adequately inflate the cuff 10 mmhg above cut off and then slowly deflate i hear muffled beats until i reach the first clear thump and it confuses me about which sound i should have considered as the "first" so is it the first loudest thump? or the first muffled ?
Please help ....I am a doctor currently in my internship.....I have measured old patients who have diastolic sound till the end 0 mmhg....how to define diastolic pressure on that case .... Thanks
As you may know, no one has a diastolic pressure of zero. It's literally impossible. I'd consider whether the sphygmomanometer you use has been adequately calibrated, particularly if it's a portable aneroid type similar to this one: sjmedsupply.com/wp-content/uploads/2013/06/legacy-aneroid-sphygmomanometer-black-nylon-cuff-thigh-01-110-027-lr.jpg The calibration of that type is relatively easy to damage by dropping it, or it may even be poorly calibrated out of the box. If the needle doesn't rest at zero when the valve is fully open, its definitely miscalibrated, but even if it does rest at zero, it may still be miscalibrated. Another possibility is that you are hearing something else that you are misidentifying as the Korotkoff sounds. First thing I'd do if I encountered a patient who seemed to have Korotkoff sounds all the way down to zero is to use a different cuff to confirm the finding, and also to find a colleague whose skills you trust to check the patient's pressure themselves. With that, you can at least narrow down whether the issue is equipment, technique, or your interpretation of what you are hearing.
Different arm positions below heart level have significant effects on blood pressure readings. The leading guidelines about arm position during blood pressure measurement are not in accordance with the arm position used in the Framingham study, the most frequently used study for risk estimations.
Sure, it's possible. However, is such a wide pulse pressure (pulse pressure = SBP - DBP) were real, it would imply some underlying pathology. Classically, it would suggest aortic regurgitation (i.e. a "leaky" aortic valve), but wide pulse pressures are also seen in elderly patients with calcified aortas. A very approximate way to tell if this blood pressure is "real" is to feel someone's pulse. The observed strength of the pulse as felt by your fingers is a rough gauge of the pulse pressure. So a patient whose BP was 170/40 should have an unusually strong pulse. On the other hand, if this BP reading was measured by a machine rather than a person, the most likely explanation is the machine is just wrong, and the BP should be rechecked with a manual measurement as demonstrated in the video.
What is the proper arm positioning for measuring BP? I get 2 different measurements very consistently, depending on my arm position. Whilst sitting up straight, it is generally around the 120/80 if I rest my arm on the side of the couch, but if I drop my arm in a relaxed position parallel to my torso, it will rise 10 points or more on each end.
UPDATE: The consensus definition of hypertension (i.e. the cutoff BP of defining hypertension) has changed since this video was posted. I'm not fully convinced by the evidence behind this change, but the updated definitions are summarized on a table here: www.heart.org/-/media/health-topics-images/hbp/blood-pressure-readings-chart-english.jpg?la=en
The evidence is pharma profits.
I'm curious. Why are you not convinced of the evidence behind the change? In any case, thanks for the update! Very helpful video too.
Thanks for the information.
You are great doctor Eric, I am studying completely from your videos, here in Syria
Hello, I satrt working finally as a graduated doctor tomorrow! And I wanted to thank you because you literally helped me to pass all my internal exams in the university! And I will continue watching your videos!❤❤
I’ve watched so many videos on this to figure this out and I finally get it because of this video so thanks!
Glad it helped!
Likewise
Excellent video! Great idea exploring the whats whys and hows, and not partially covering the subject. Science should always be precisely communicated
Very well made. Clear, detailed, understandable.
Very helpful. Includes all of the important content. Thanks!!
Thank you for being extremely competent!
Very informative. I could understand this very important medical process , clearly. Thanks
Nicely done. Professional level instruction.
The best tutorial. Thank you
Very useful lect8ure both for beginners and clinicians. Thank you .
one of the best vids out here. ty
Your video is very helpful doctor ❤
So well made . All is covered . Thx
Thank you very much ☺️☺️☺️😊❤️very well explained, and not too slow or too fast
The threshold, as I learned from watching "John Q", for systolic blood pressure that leads to dangerous hypotension, is this ----
The optimal systolic BP to maintain health is 80 or more if it is low, but anything under 80 is a warning sign. A systolic BP of under 70 is a medical emergency and has to be resolved by raising systolic BP to 70 or more ASAP. Failure to keep that pressure at 70 or above at that point can lead to serious complications - one of which is fatal heart failure.
Low blood pressure doesn't cause heart failure. Instead, advanced heart failure (and the treatments for heart failure) can cause low pressure.
What about the cheap automatic measuring tools that we can buy? Are they any accurate?
How to measure blood pressure in atrial fibrillation
Hello, very useful video thank you from Italy
The video incorrectly identifies the reason for the Korotkoff sounds. These sounds are due to the turbulence of the blood as it moves through the partially obstructed artery. The artery does NOT alternate between compressed and open. Can you fix this error? Otherwise it is an excellent explanation on how to correctly take blood pressure measurements..
Thanks for the comment. My primary audience for this video was first year medical and nursing students, so didn't want to get too into the details of the mechanism of Korotkoff sounds, but probably could have been more explicit that the precise mechanism of their generation is amazingly still not known for certain.
Regarding whether the sounds are from alterations between relatively compressed and open states, or from turbulent flow through a partially obstructed artery that's relatively static, papers have been published providing support for both views. The most recent entry into the literature on this topic is one that puts forth a model similar to the former (which the author has called the "wall resonance hypothesis"). The author posits that the sounds are caused by the arterial walls "ringing at a natural resonant frequency determined by the elasticity and dimensions of the artery wall and the mass of outward moving tissue" caused by the transition between the artery being in a buckled state (i.e. arterial pressure below cuff pressure) and an expanded state (i.e. arterial pressure above cuff pressure).
docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1064&context=bmepubs (Disclaimer: I am not an engineer, so cannot vouch for the accuracy of his work.)
But I should have been more clear about the uncertainty.
Is there substantial difference between different manual sphygmomanometers? I want to purchase a professional grade one but don't know which to choose...is there an industry standard that I should look for?
Thanks!
Mercury sphygmomanometers were considered to be the gold standard for most of the last century, and are probably still the most accurate of the manual devices. However, concerns over the toxicity of mercury have led to these falling out of favor, and it would be pretty unusual for an individual clinician to own one. Among the aneroid sphygmomanometers (any BP measuring device with a round gauge and a needle - like the one in the video), I don't know of any consensus as to which style and/or brand is best. Aneroid devices are fragile however, and just a single drop on to a hard surface can render one ruined beyond repair. Also, from an N of 1, I purchased a relatively cheap one branded with an American drug store chain for casual/non-official use, and it "broke" (i.e. no longer zeroed) after just a few uses spread out over 6 months. So I would not recommend going with the cheapest one you could find...
Good video, help me lots
I have a few really annoying set of patients where after i adequately inflate the cuff 10 mmhg above cut off and then slowly deflate i hear muffled beats until i reach the first clear thump and it confuses me about which sound i should have considered as the "first"
so is it the first loudest thump? or the first muffled ?
is there any large difference between laying and sitting BP? if both done properly?
presented very well, thank you
thanks for your help
very helpful. thanks
Please help ....I am a doctor currently in my internship.....I have measured old patients who have diastolic sound till the end 0 mmhg....how to define diastolic pressure on that case ....
Thanks
As you may know, no one has a diastolic pressure of zero. It's literally impossible. I'd consider whether the sphygmomanometer you use has been adequately calibrated, particularly if it's a portable aneroid type similar to this one: sjmedsupply.com/wp-content/uploads/2013/06/legacy-aneroid-sphygmomanometer-black-nylon-cuff-thigh-01-110-027-lr.jpg
The calibration of that type is relatively easy to damage by dropping it, or it may even be poorly calibrated out of the box. If the needle doesn't rest at zero when the valve is fully open, its definitely miscalibrated, but even if it does rest at zero, it may still be miscalibrated.
Another possibility is that you are hearing something else that you are misidentifying as the Korotkoff sounds.
First thing I'd do if I encountered a patient who seemed to have Korotkoff sounds all the way down to zero is to use a different cuff to confirm the finding, and also to find a colleague whose skills you trust to check the patient's pressure themselves. With that, you can at least narrow down whether the issue is equipment, technique, or your interpretation of what you are hearing.
excellent video once again. Please make videos on clinical skills and create a playlist for it
please tell the pros and cons of electronic monitoring of BP
This was very useful, thank you
Dear Prof, what is the optimal pressure in kids? thanks
Dr. Strong, does the height of the pressure gauge (wall mounted) affect readings? Appreciate any references that discuss this topic.
Different arm positions below heart level have significant effects on blood pressure readings. The leading guidelines about arm position during blood pressure measurement are not in accordance with the arm position used in the Framingham study, the most frequently used study for risk estimations.
Is this possible that a systolic Bp reading shows 170 and diastolic bp reading shows 40...
Sure, it's possible. However, is such a wide pulse pressure (pulse pressure = SBP - DBP) were real, it would imply some underlying pathology. Classically, it would suggest aortic regurgitation (i.e. a "leaky" aortic valve), but wide pulse pressures are also seen in elderly patients with calcified aortas. A very approximate way to tell if this blood pressure is "real" is to feel someone's pulse. The observed strength of the pulse as felt by your fingers is a rough gauge of the pulse pressure. So a patient whose BP was 170/40 should have an unusually strong pulse.
On the other hand, if this BP reading was measured by a machine rather than a person, the most likely explanation is the machine is just wrong, and the BP should be rechecked with a manual measurement as demonstrated in the video.
I didn't get the point explained at 5:45
Some say the last sound is diastolic and some say the no sound (phase 5) is diastolic
Thank you
how do you cler the readings ??
Thank you!
Very useful information. Thanks
What is the proper arm positioning for measuring BP? I get 2 different measurements very consistently, depending on my arm position. Whilst sitting up straight, it is generally around the 120/80 if I rest my arm on the side of the couch, but if I drop my arm in a relaxed position parallel to my torso, it will rise 10 points or more on each end.
It was helpfull welldone
Thank you so much sir
Thanks
Thanks 😍
Thank you sir....
Why do some nurses take it on the forearm isn't that wrong
AS LONG AS YOUR ON THE VEIN/ARTERY
amazing video. I'm not even a medical student, maybe time for a change in career
Thank you so much!
Lacking practical measurement of BP
❤
பாரம் சுந்தரி
Forum.
Thank you very much!!