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Can BP Vary With Different Arm Positions?
Question: Hello, my question is regarding blood pressure. My blood pressure varies a lot with arm position. If i sit on a chair and put my arm on a table at almost chest height , i get reading that average about 125/88. However, if I put my arm lower - around waist height i get reading of 140/100. This is the case at my doctors office and grocery stores. I always get high reading there because the arm position is lower. I am confused as to which reading to follow. Please advice.
Brief Answer:
the recommendations are for heart level
Detailed Answer:
Hi, thanks for using healthcare magic
There are certain world wide recommendations when measuring blood pressure. It can be affected by different factors including the position of the arm.
The blood pressure should be measured with the arm at heart level. When the arm is lower than heart level then the blood pressure is falsely high, when it is taken higher than heart level the blood pressure is falsely lower than the actual reading.
This is related to something called hydrostatic pressure, when the arm is too low, the hydrostatic pressure between the column of blood in the heart and the point of measurement is added to the reading.
This is the reason your blood pressure is higher when your arm is held lower. This reading is not accurate. 2 mmHg of blood pressure is approximately added for every inch below the heart ( and 2 mmHg substracted for every inch above)
The accurate reading is the one taken at heart level.
Other factors are: (1) crossing of feet (can raise systolic by 2 to 8 mmHg)
(2)room temperature
(3)alcohol or nicotine
(4)recent exercise
(5)bladder distension
(6)background noise
I hope this helps, feel free to ask any other questions
the recommendations are for heart level
Detailed Answer:
Hi, thanks for using healthcare magic
There are certain world wide recommendations when measuring blood pressure. It can be affected by different factors including the position of the arm.
The blood pressure should be measured with the arm at heart level. When the arm is lower than heart level then the blood pressure is falsely high, when it is taken higher than heart level the blood pressure is falsely lower than the actual reading.
This is related to something called hydrostatic pressure, when the arm is too low, the hydrostatic pressure between the column of blood in the heart and the point of measurement is added to the reading.
This is the reason your blood pressure is higher when your arm is held lower. This reading is not accurate. 2 mmHg of blood pressure is approximately added for every inch below the heart ( and 2 mmHg substracted for every inch above)
The accurate reading is the one taken at heart level.
Other factors are: (1) crossing of feet (can raise systolic by 2 to 8 mmHg)
(2)room temperature
(3)alcohol or nicotine
(4)recent exercise
(5)bladder distension
(6)background noise
I hope this helps, feel free to ask any other questions
Note: For further queries related to coronary artery disease and prevention, click here.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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