Which statement is true regarding auscultatory gaps in BP measurement?

Which statement is true regarding auscultatory gaps in BP measurement?

• A. An auscultatory gap can cause underestimation of systolic blood pressure or overestimation of diastolic blood pressure.
• B. Auscultatory gaps occur in every adult over 60 years old.
• C. BP measurement is unaffected by auscultatory gaps.
• D. An auscultatory gap only affects diastolic readings.

Answer: (A)

An auscultatory gap is a brief interval during cuff deflation when no Korotkoff sounds are heard, even though the arterial pressure is still between systolic and diastolic values. This gap is more common in people with hypertension or arterial stiffness, such as some older adults. Because systolic blood pressure is determined by the appearance of the first Korotkoff sound, if that initial sound is missed during the gap, the cuff pressure at which you record systolic will be lower than the true value, leading to an underestimation. Likewise, diastolic pressure is tied to the point where sounds disappear; if the gap causes sounds to resume later or alters when you perceive them as ending, the recorded diastolic pressure can end up higher than the true value, producing an overestimation. In short, an auscultatory gap can cause both underestimation of systolic and overestimation of diastolic readings, which is why this statement is correct. To reduce error, take multiple readings, use slower deflation, and consider palpating the systolic value if a gap is suspected.

An auscultatory gap is a brief interval during cuff deflation when no Korotkoff sounds are heard, even though the arterial pressure is still between systolic and diastolic values. This gap is more common in people with hypertension or arterial stiffness, such as some older adults. Because systolic blood pressure is determined by the appearance of the first Korotkoff sound, if that initial sound is missed during the gap, the cuff pressure at which you record systolic will be lower than the true value, leading to an underestimation. Likewise, diastolic pressure is tied to the point where sounds disappear; if the gap causes sounds to resume later or alters when you perceive them as ending, the recorded diastolic pressure can end up higher than the true value, producing an overestimation. In short, an auscultatory gap can cause both underestimation of systolic and overestimation of diastolic readings, which is why this statement is correct. To reduce error, take multiple readings, use slower deflation, and consider palpating the systolic value if a gap is suspected.