A sphygmomanometer is an instrument used to measure systolic and diastolic blood pressure. Therefore it can be used to measure the blood pressure in the human body.
- Inflatable cuff
- A measuring unit (mercury manometer)
- A mechanism for inflation
- A manually operated bulb and valve
- A stethoscope if the sphygmomanometer is manual.
Types of Sphygmomanometer
- Manual sphygmomanometer
- Digital sphygmomanometer
- We wrap the cuff around the arm. At roughly the same vertical height as the heart. Because
- Selecting the correct size of the cuff is very important. Too small a cuff results in too high a pressure. While too large a cuff results in too low a pressure because of the size of the cuff.
- While listening with a stethoscope to the brachial artery at the elbow, the examiner slowly releases the pressure in the cuff, therefore, releasing off pressure.
- When blood flow first starts again in the artery, we hear a “whooshing” or pounding sound because of bb
- This sound is systolic blood pressure because it is systolic bp.
- Then we release the cuff pressure until the sound stops. This is recorded as the diastolic blood pressure because it is diastolic bp.
We use a stethoscope for the auscultatory method. The first continuous Korotkoff sounds identify the systolic blood pressure. The moment when Korotkoff sounds disappear identifies diastolic blood pressure.