Function ofbulb of sphygmomanometer? - Answers

The function of the bulb of a manual sphygmomanometer is to inflate the cuff to stop the flow of arterial blood in the arm so that the blood pressure can be determined. The bulb pumps air into the cuff, causing it to expand against the upper arm. Enough air is pumped into the cuff to stop the flow of arterial blood. The pressure is then slowly released and the point at which blood begins to flow again is recorded as the systolic pressure, representing the highest arterial pressure of the cardiac cycle. Blood flows only with the beating of the heart, however, and further pressure is released until the arterial blood flows freely. This point is recorded as the diastolic pressure, representing the lowest arterial pressure when the heart is at rest.