Math Problem

[Dylab]

Someone on another Forum posted this question and for some reason I get the answer. What do you guys think?

When physicians diagnose arterial blockages, they quote the reduction in flow rate. If the flow rate in an artery has been reduced to 10% of its normal value due to plaque formation, and the average pressure difference has increased by 20%, by what factor has the clot reduced the radius of the artery?

 

[Iamme]

Dylab---Are you sure that this posed question is a serious medical related question that really has an answer? My dad had a heart procedure done, and all I ever heard about was percentage of blockage. I would hacve to think that there are variables involved with flow rates and pressures, that would vary from individual to individual, and may not be able to be calculated by some formula based on the information you gave. When you say about the pressure differenced INCREASING by 20%, are you referring to a 20% spread increase between diastolic and systolic pressure? (I.e., at 100% open artery, BP= 120/80. But with 10% open artery BP is now 150/90).

Or, are you simply implying that flow (volume) has decreased by 90%, while the pressure has gone up 20%? Sort of like how by restricting the end of a garden hose, you kill some of the flow, yet the speed of the water that comes out, increases.