Regular measurement of blood pressure is important for monitoring a patient's overall cardiovascular health. Blood pressure can be divided into two numbers: the systolic and diastolic pressure. The diastolic pressure is the lower of the two blood pressure readings. Elevated diastolic pressure can put a patient at a higher risk of developing heart disease and a stroke. Although diastolic pressure can be measured using automated machines, the most accurate readings are obtained using a stethoscope and a blood pressure cuff (also known as a sphygmomanometer).
Step 1
Wrap the blood pressure cuff around the patient's upper arm. According to Santa Monica University's Anatomy course page, the cuff should be snugly wrapped around the upper arm with its lower edge approximately one inch above the elbow. The cuff should then be fastened using the velcro strip.
Step 2
Place the bell of the stethoscope against the inside of the upper arm just underneath the lower edge of the blood pressure cuff. Place the stethoscope's ear pieces in your ears.
Step 3
Tighten the screw on the cuff's air valve by turning it clockwise. Pump the cuff using the hand pump until the pressure in the cuff's gauge reads 180 millimeters of mercury.
Step 4
Slowly open the air valve by turning the screw counterclockwise. Open the valve just enough so that the pressure on the gauge drops slowly but steadily.
Step 5
Listen for Korotkoff sounds using the stethoscope as the pressure in the cuff drops. According to the Univerisity College London's Medical Physics Department, the Korotkoff sounds are the sounds of blood pulsing through the arteries and resemble a tapping or blowing sound that coincides with the patient's pulse. They can first be heard when the pressure in the cuff is equal to the patient's systolic pressure and then become inaudible when the cuff's pressure is at the patient's diastolic blood pressure.
Step 6
Write down the gauge pressure at which you can no longer hear the Kosotkoff sounds. That is the patient's diastolic pressure.
Tips and Warnings
- Make sure that the upper arm is relaxed and at heart level when measuring the diastolic pressure. Muscle tension and abnormal elevation (either higher or lower than the heart) can affect blood pressure readings.
Things You'll Need
- Sphygmomanometer
- Stethoscope
