I am trying to work with the simplified Bernoulli equation to determine how to convert a drop in flow velocity across a stenosis (narrowing) into a change in hemodynamic pressure. Radiologists often use Doppler ultrasound to measure flow velocity change in a blood vessel with a stenosis- but I would like to make a conversion to a pressure differential.(adsbygoogle = window.adsbygoogle || []).push({});

Equation: P2-P1 = (V2^2 - V1^2)/2 (assuming frictionless system, blood density ~ 1.0 gm/cm^3, and no change in height)

P2-P1 = [(126 cm/sec)^2 - (90 cm/sec)^2]/2 (^ symbol= raise to power of)

Can someone show me how to convert the units of (cm/sec)^2 to mmHg? Or show me where my error in thinking is?

Thank you kindly,

Scott

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# Converting velocity to pressure

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