Name: korotkoff sounds during blood pressure checks
Uploaded: 2025-05-22T09:05:46.000Z
Duration: 1 min 12 s
Channel: JoVE

Korotkoff sounds are a sequence of sounds corresponding to shifts in blood flow through an artery during gradual cuff deflation in a blood pressure assessment.
When the cuff is inflated beyond the systolic pressure, it completely blocks blood flow, resulting in the absence of Korotkoff sounds.
These sounds appear when the cuff pressure equals the systolic blood pressure and are audible in five distinct phases.
During phase one, a gentle and distinct tapping sound emerges, indicating the systolic pressure reading.
In phase two, the tapping sounds gradually diminish, accompanied by a gentle swishing sound.
During phase three, the tapping sounds become crisper and more intense but remain softer compared to phase one.
In phase four, softer, muffled sounds are heard as the cuff pressure is released. The first diastolic reading marks the change from tapping to a muffled sound.
Finally, in the fifth phase, all sounds disappear as the cuff deflates, indicating normal blood flow. This point is marked as the diastolic blood pressure.

korotkoff sounds

Korotkoff Sounds

Korotkoff sounds are the specific sounds heard while measuring blood pressure using a sphygmomanometer, typically with a stethoscope or a Doppler device. They are named after Russian physician Nikolai Korotkov, who first described them in 1905. These sounds correspond to turbulent blood flow in the artery as the blood pressure cuff is gradually released after inflation.
During blood pressure assessment, inflating the cuff 30 millimeters of mercury above the patient&#39;s systolic blood pressure leads to the absence of Korotkoff sounds due to complete blood flow occlusion. These sounds appear when the cuff pressure equals the patient&#39;s systolic blood pressure and are audible through a stethoscope, or Doppler positioned distal to the cuff. Korotkoff sounds have five distinct phases:
<ol>
	<li>Phase One (Appearance of faint tapping sounds): As the cuff&#39;s pressure is released, the first faint tapping sounds become audible. This initial appearance marks the systolic pressure reading, with the intensity gradually increasing.&#160;&#160;</li>
	<li>Phase Two (Softer tapping sounds with swishing): The tapping sounds become softer, accompanied by a swishing sound as the cuff deflates. The characteristics of these sounds provide additional information about blood flow.</li>
	<li>Phase Three (Crisp, intense tapping sounds): As the cuff pressure continues to fall, phase three features crisp and intense tapping sounds, softer than in phase one. These sounds indicate increased blood flow through the artery.</li>
	<li>Phase Four (Softer and muffled sounds): With further decrease in cuff pressure, phase four comprises softer and muffled sounds. The transition from tapping to muffled sounds during this phase signifies the first diastolic reading.</li>
	<li>Phase Five (Total disappearance of sounds): The final phase is characterized by the total disappearance of all Korotkoff sounds, indicating complete cuff deflation and normal blood flow, representing diastolic blood pressure.</li>
</ol>
Understanding the progression of Korotkoff sounds through these five phases is essential for healthcare professionals to obtain accurate blood pressure readings and assess cardiovascular health.

Korotkoff sounds are the specific sounds heard while measuring blood pressure using a sphygmomanometer, typically with a stethoscope or a Doppler device. ...

Education

JoVE Core

Nursing

Unit 1

Vital Signs: Blood Pressure

KEY TERMS AND CONCEPTS

korotkoff sounds during blood pressure checks

Korotkoff sounds are the sounds heard during a blood pressure check with a sphygmomanometer. A stethoscope or a Doppler device is usually placed below the cuff to listen for them. These sounds were first described by Russian physician Nikolai Korotkov in 1905.

Korotkoff sounds appear when the cuff pressure falls to the patient’s systolic blood pressure. Before that point, inflating the cuff about 30 millimeters of mercury above systolic pressure blocks blood flow, so no sounds are heard. As the cuff is released, turbulent blood flow in the artery creates the sound pattern used to measure blood pressure.

The sounds change in five phases as the cuff deflates. Phase one begins with faint tapping sounds, and this first appearance marks the systolic reading. Phase two brings softer tapping with a swishing sound. Phase three has crisp, intense tapping that is still softer than phase one.

Phase four is marked by softer, muffled sounds. The change from tapping to muffled sounds signals the first diastolic reading. In phase five, the sounds disappear completely. That disappearance shows complete cuff deflation and normal blood flow, which represents the diastolic blood pressure reading.

Korotkoff Sounds During Blood Pressure Checks

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Korotkoff sounds are the sounds heard during a blood pressure check with a sphygmomanometer. A stethoscope or a Doppler device is usually placed below the cuff to listen for them. These sounds were first described by Russian physician Nikolai Korotkov in 1905. Korotkoff sounds appear when the cuff pressure falls to the patient’s systolic blood pressure. Before that point, inflating the cuff about 30 millimeters of mercury above systolic pressure blocks blood flow, so no sounds are heard. As...

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key terms and concepts

Learn how Korotkoff sounds appear during blood pressure measurement, how cuff pressure affects them, and what each of the five phases shows.

Korotkoff Sounds During Blood Pressure Checks | JoVE K12

JoVE Core Nursing offers concise animated lessons on nursing practices, covering health systems, nursing organizations, and health concepts. It includes practical communication, infection prevention, and nursing fundamentals, providing students with a clear understanding of nursing principles.

Korotkoff Sounds During Blood Pressure Checks

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