When measuring blood pressure manually and listening for Korotkoff sounds, the diastolic blood pressure is measured at the onset of
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Phase 1
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Phase 2
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Phase 3
4) Phase 5
explanation
Korotkoff sounds are used to interpret blood pressure when using a stethoscope and a noninvasive blood pressure cuff, and is described in 5 phases of sound. Phase 1 heralds the onset of the first sound heard and correlates with the systolic blood pressure. Phase 5 occurs at the cuff pressure at which the sound first disappears, and is the phase recommended by the American Heart Association to correspond most reliably with the diastolic heart sound. In cases where Phase 5 does not occur (the sound never fully disappears), Phase 4 is then used to represent the diastolic blood pressure, and is described as a thumping or muting of the sound just before diastole. Phases 2 and 3 have no clinical significance.