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The equation delta P = Q x R
where delta P = (i think) is the pressure difference between two points in the vessel
Q= flow
R= Resistance
So, I was wondering, does delta P mean what I describe above? Also, I know this may sound stupid but I am kinda confused after doing some passages and i want to make sure I understand the relationships correctly, so please don't laugh/ridicule my questions.
1) Does this equation say that as we keep the pressure constant in the vessel, that by increasing the resistance we will decrease flow?
I remember reading a passage similar to this where a guy was running on the treadmill, and despite him exercising, his BP was constant. Is this even possible? (if you exercise, CO increases, which means your pumping more blood per minute, and since theirs more blood in the arterioles wouldn't the pressure have to increase since arteriole vasoconstriction is what diverts blood to specific tissues that need it (ie exercising muscle).
2) Does increasing the pressure within the vessel increase flow? (assuming that resistance is constant)
^I'm really confused about the delta P term, because I believe that pressure differences are what drive flow. Fluids flow from an area of high pressure to lower pressure. So, thats why I am wondering if increasing the delta P term means there is either (1) a greater pressure difference between two points within the vessel OR (2) the pressure just increased because we reduced the diameter of the vessel due to constriction of the vessel (but then in this case R could not be constant since resistance would increase if we reduced the vessel diameter)
lastly, is this an analog to Ohm's law? I tried thinking about it that way to see if I could relate similarities. Would the delta P term be analogous to voltage, since a potential difference is what drives current, which would be analogous to a pressure difference within the vessel driving the movement of fluid. And Q is analogous to I, the current. And resistance, R is well, equal to the resistance within the circuit, which is why when we increase resistance we reduce current, so when when increase resistance we would reduce Q in this case.
basically, am I correct in thinking that this equation states on 2 things about flow. Its saying that flow, Q can only be affected by either changing the resistance within the vessel or by changing the pressure? and any time we change one variable, do we have to assume that the other is constant? <this always trips me up. Thanks guys for sharing
where delta P = (i think) is the pressure difference between two points in the vessel
Q= flow
R= Resistance
So, I was wondering, does delta P mean what I describe above? Also, I know this may sound stupid but I am kinda confused after doing some passages and i want to make sure I understand the relationships correctly, so please don't laugh/ridicule my questions.
1) Does this equation say that as we keep the pressure constant in the vessel, that by increasing the resistance we will decrease flow?
I remember reading a passage similar to this where a guy was running on the treadmill, and despite him exercising, his BP was constant. Is this even possible? (if you exercise, CO increases, which means your pumping more blood per minute, and since theirs more blood in the arterioles wouldn't the pressure have to increase since arteriole vasoconstriction is what diverts blood to specific tissues that need it (ie exercising muscle).
2) Does increasing the pressure within the vessel increase flow? (assuming that resistance is constant)
^I'm really confused about the delta P term, because I believe that pressure differences are what drive flow. Fluids flow from an area of high pressure to lower pressure. So, thats why I am wondering if increasing the delta P term means there is either (1) a greater pressure difference between two points within the vessel OR (2) the pressure just increased because we reduced the diameter of the vessel due to constriction of the vessel (but then in this case R could not be constant since resistance would increase if we reduced the vessel diameter)
lastly, is this an analog to Ohm's law? I tried thinking about it that way to see if I could relate similarities. Would the delta P term be analogous to voltage, since a potential difference is what drives current, which would be analogous to a pressure difference within the vessel driving the movement of fluid. And Q is analogous to I, the current. And resistance, R is well, equal to the resistance within the circuit, which is why when we increase resistance we reduce current, so when when increase resistance we would reduce Q in this case.
basically, am I correct in thinking that this equation states on 2 things about flow. Its saying that flow, Q can only be affected by either changing the resistance within the vessel or by changing the pressure? and any time we change one variable, do we have to assume that the other is constant? <this always trips me up. Thanks guys for sharing