By how much should the sphygmomanometer cuff be inflated above palpatory systolic pressure?

The sphygmomanometer cuff should be inflated to a level that is at least 30 mm Hg above the palpatory systolic pressure. This practice ensures that the cuff pressure is sufficiently high to occlude the brachial artery completely, allowing for an accurate reading of systolic blood pressure when deflating the cuff.

Inflating the cuff by 30 mm Hg above the palpatory systolic pressure provides a buffer that can account for any variability in the measurement process. This helps avoid situations where the actual systolic pressure may be underestimated if the cuff is not inflated adequately. By following this guideline, the health professional can ensure that they do not encounter the issue of the sounds of blood flow (Korotkoff sounds) beginning below the expected level, which could result in an inaccurate assessment of the patient's blood pressure.

Other inflation levels might not provide the same degree of reliability necessary for an accurate measurement, leading to potential misdiagnosis or inadequate monitoring of the patient’s cardiovascular status.