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Stanford Medicine 25 An Initiative to Revive the Culture of Bedside Medicine

#17 BP & Pulsus Paradoxus

Key Learning Points

  • Overview of the basics of blood pressure measurement
  • How to measure pulsus paradoxus (see video)
  • Other signs of pericardial tamponade



Blood Pressure Measurement

Introduction: Few realize that the measurement of blood pressure is highly skill-dependent. A practiced technique allows a physician to take an accurate reading when the result may guide clinical decision making. Below are some steps to help make an accurate measurement.



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Historical Perspective

The first measurement of blood pressure what recorded in 1711 by Reverend Stephen Hales using a glass tube he inserted into the artery of a horse. The first truly accurate measurement of blood pressure in man was not until 1856 when the surgeon Faivre connected a mercury manometer to an exposed femoral artery during limb amputation. In that same year, Karl Vierordt used pressure to obliterate the radial pulse to approximate blood pressure non-invasively for the first time. This technique was greatly advanced by Etiennes Jules Marey who used the mercury manometer to record systolic pressure non-invasively.



Pulsus Paradoxus


ronald wittelesDr. Ronald Witteles is certified in Internal Medicine and Cardiology. He serves as the Stanford Internal Medicine Program Director, Associate Director of the CCU and Co-Director, Stanford Amyloid Center.


Clinical Pearl: When testing for pulsus paradoxus, simply focus on the korotkoff sounds. There is no need to watch the patient's respirations.


Consult the Expert



Other Signs of Cardiac Tamponade