lab 13 sounds

cuff pressure

You pump the cuff up to a pressure higher than systolic (140) and you release air slowly to gradually decrease 

why is there no sound when cuff pressure = 140 mmHg?

cuff pressure is higher than systolic pressure, the brachial artery is completely closed, and no blood flows, so no sound is heard.

What does the first Korotkoff sound represent?

It occurs when cuff pressure decreases to (120) & = systolic pressure (120)

constriction of the brachial artery decreases and blood begings flow creating the first sound 
→ First sound = systolic BP.

Why do you hear sounds at cuff pressure = 100 mmHg?

cuff pressure has decreases to a value is between systolic and diastolic

sound is heard at every systole which is when the artery opens

What does the last Korotkoff sound represent?

When cuff pressure(80) = diastolic pressure (80)

This is the last audible sound, which marks the diastolic BP.

What happens when cuff pressure drops below diastolic pressure

The artery is fully open, blood flow becomes smooth (laminar), and no sounds can be heard.