Using a cuff that is too small for the arm tends to cause which reading outcome?

Using a cuff that is too small for the arm tends to cause which reading outcome?

• A. Higher than true systolic and diastolic pressures
• B. Lower than true systolic and diastolic pressures
• C. Only systolic pressure to rise
• D. No change in readings

Answer: (A)

A cuff that is too small produces readings that are higher than the true systolic and diastolic pressures. The cuff must fully encircle the arm and have enough width to apply pressure evenly. When the cuff is narrow, the same cuff pressure translates into a higher localized force on a smaller area, so it takes a higher cuff pressure to occlude the brachial artery. As you deflate, the point at which you first hear the Korotkoff sounds (systolic) and the point at which they disappear (diastolic) occur at higher pressures than the actual arterial pressures. So both values tend to be overestimated. To avoid this, use a properly sized cuff—width about 40% of arm circumference and bladder length appropriate for the arm.

A cuff that is too small produces readings that are higher than the true systolic and diastolic pressures. The cuff must fully encircle the arm and have enough width to apply pressure evenly. When the cuff is narrow, the same cuff pressure translates into a higher localized force on a smaller area, so it takes a higher cuff pressure to occlude the brachial artery. As you deflate, the point at which you first hear the Korotkoff sounds (systolic) and the point at which they disappear (diastolic) occur at higher pressures than the actual arterial pressures. So both values tend to be overestimated. To avoid this, use a properly sized cuff—width about 40% of arm circumference and bladder length appropriate for the arm.