Instructions on Using a Sphygmomanometer

A sphygmomanometer is a device used to measure blood pressure. A sphygmomanometer consists of an inflatable cuff, or compression bag, with a bulb at the end of a rubber tube. The bulb is used to inflate the cuff. Attached to the bulb is also an exhaust valve which is used to release the air and deflate the cuff. There is also a manometer, or gauge, attached where the pressure is read. Sphygmomanometers are typically aneroid, which means free of fluids. Mercury sphygmomanometers are still in existence, and are usually used to calibrate aneroid cuffs. But due to the hazards of exposure to mercury if a sphygmomanometer breaks, they are not typically found in hospitals anymore.

Things You'll Need

• Stethoscope
• Sphygmomanometer

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Instructions

• 1

  Instruct the patient to sit comfortably, with the arm just slightly bent, palm up, with the forearm supported at heart level.

• 2

  Place the deflated cuff around the upper arm, with the lower edge of the cuff about one inch above the elbow crease. The arm should be bare, and not constricted by tight clothing.

• 3

  Place the stethoscope lightly on the antecubital space. The antecubital space is the crease in the elbow joint just over the brachial artery.

• 4

  Inflate the cuff to 20 to 30 mm HG above the point at which the pulse disappears.

• 5

  Release the pressure slowly using the valve. The air should be released at a rate of 2 to 3 mm Hg per second.

• 6

  Listen for thumping sounds through the stethoscope. These thumping sounds are called the Korotkoff sounds. Once you hear the first Korotkoff sound you should note the pressure on the gauge at which you heard it. That will be the patient's systolic pressure, or the top number. Once the Korotkoff sounds disappear, that pressure is the diastolic pressure, or the bottom number.