There are five distinct phases of Korotkoff sounds, each associated with different points in the blood pressure measurement process:
1. Phase I: The first appearance of faint, clear tapping sounds, which gradually increase in intensity. The first sound heard is noted as the systolic blood pressure. 2. Phase II: A swishing or murmur sound follows as the cuff pressure continues to decrease. 3. Phase III: Crisper and louder sounds compared to Phase II. 4. Phase IV: A sudden muffling of the sound, which becomes softer and less distinct. 5. Phase V: The point at which sounds completely disappear, indicating the diastolic blood pressure.
