Cardio 1 Flashcards
Convert 1 mmHg to Dynes…
1mmHg = .013 dynes/cm3
What is the absolute viscosity of water in dynes sec/cm2?
What is the viscosity of blood in dynes sec/cm2?
.01 dynes sec/cm2 – water
.04 dynes sec/cm2 – blood.
What does the downstroke of the pump system do?
The downstroke creates a back pressure on the left valve closing it, and a forward pressure on the right valve opening it, driving blood into the right vessel and chamber.
How does the upstroke happen on the pump?
Since there is no longer pressure being put on either valve by the pump, the right valve will close due to the back pressure of the right vessel and the left valve will open due to the forward pressure in the left vessel. No resist from the pump, the pump naturally resets.
What is the effect of increasing right vessel radius?
The pump has to work against right vessel resistance during the down stroke. As the right vessel radius is increased (reducing resistance) the pump rate increases resulting in an increased blood low (CO) at constant stroke volume.
What is the effect of increasing left vessel radius?
Descreases the resistance to blood flow into the pump chamber. = a much more rapid passive upstroke rate. =increased blood flow (CO) at constant stroke volume.
Effect of increasing stroke volume/
As the stroke volume is increased the time of the downstroke is increased and the stroke rate is decreased. The increase in SV and decrease in Stroke Rate offset and (CO) remains constant.
Effect of Increasing pump pressure.
As pump pressure increases, stroke rate and blood flow increase. (increases in pump pressure will result in an increased pressure difference and an increased stroke rate.
Effect of decreasing right chamber pressure.
Decreasing right chamber pressure increases pressure difference resulting in an increased stroke rate. Therefore, as right chamber pressure decreases stroke rate and blood flow increase.
Effect of increasing left chamber pressure
Increasing left chamber pressure increases the blood flow rate into the pump chamber during the passive upstroke phase of the cycle. Therefore, as left chamber pressure increases stroke rate and blood flow increase.
