What deflation rate is recommended and why?

• A. 5–6 mmHg per second.
• B. 0.5–1 mmHg per second.
• C. 10 mmHg per second.
• D. 2–3 mmHg per second to allow clear Korotkoff sounds and accurate detection of SBP/DBP.

Answer: (D)

The key idea here is how the cuff deflation rate affects your ability to hear and identify the Korotkoff sounds clearly. You want the pressure to fall at a pace that lets those sounds start, change, and disappear precisely as the cuff pressure crosses the systolic and diastolic values. A rate of about 2–3 mmHg per second provides that balance: it’s slow enough to hear the first tapping sound as SBP is reached and to notice the point where sounds fade away as DBP is reached, ensuring accurate measurements. If you deflate too quickly, sounds can be missed or misread, leading to incorrect SBP or DBP. If you deflate too slowly, the process becomes uncomfortable and prolongs the measurement, increasing the chance of user error. So, 2–3 mmHg per second is the optimal pace for reliable readings.