Phases Of Korotkoff Sounds

Question 1

I

Answer 1

This is the first faint sound heard as the cuff is deflated. The number that appears on the blood pressure gauge at that moment is recorded as the systolic pressure reading. The cuff must first be inflated to a level high enough to hear this first sound during relaxation. If the cuff is not inflated high enough and a pulse is heard immediately after deflation, stop the procedure, remove the cuff, wait a couple of minutes, and then start the procedure again, inflating the cuff at least 20 mmHg above the first attempt.

Question 2

II

Answer 2

The second phase occurs as the cuff continues to be deflated and more blood flows through the artery. This sound has a swishing quality. The cuff has to be slowly deflated to hear this soft sound. An auscultatory gap is said to have occurred if there is a total loss of sound that then reoccurs later. An auscultatory gap can occur in certain cases of heart disease and hypertension and should be reported to the physician.

Question 3

III

Answer 3

During this phase, the sound will become less muffled and develop a crisp tapping sound as the blood flow moves easily through the artery. If the BP cuff was not inflated enough to hear the Phase I sound, then the Phase III sound may be heard and incorrectly stated as the systolic reading.

Question 4

IV

Answer 4

This phase is characterized by the sound beginning to fade and become muffled. The American Heart Association, which believes Phase IV is the best indicator of the diastolic pressure, recommends the reading at this phase be recorded as the diastolic pressure for a child.

Question 5

V

Answer 5

Sound will disappear during this phase. Some physicians may require both Phase IV and Phase V recorded for the diastolic pressure reading.