Flashcards in Blood Flow/ Hemodynamics Deck (43):
where is the apex of the heart?
the bottom, the point
what are the two types of circulation?
series and parallel/ systemic vs pulmonary
hemodynamics is the
study of blood flow
cardiac output, heart rate X SV
amount of blood ejected from either right or left ventricle in one beat
CO at rest is about
5L, i.e. total volume per minute
(Q), driven by pressure, limited by resistance. The pressure drops down a vessel because potential energy is used.
Total pressure change in system is equal to
Paorta * P vena cava
Total peripheral resistance
frictional resistance to blood flow provided bt all vessels between aorta and right atrium . = ALL RESISTANCE (series and parallel)
what factors contribute to resistance/ poiseuille's
radius, viscosity, length. R is most important because variable (AND ^4 in equation), small radius change results in large resistance change.
mean arterial pressure. fluctuates between diastolic and systolic pressures
DP + (SP-DP)/3
flow and velocity relationship
V= distance/time= Q/A
flow velocity cs cross sectional area
flow is constant, but velocity slows with increased divisions- fractionated! (want slow at capillaries)
meauring cardiac output with ultrasonic. Q=V*A
cardiac output-coronary circulation
artery vs vessel
artery have thick outside with small lumen, elastic and muscular.
vessels: thin wall with large lumen, low resistance. Some muscle/ valves in between function.
pressure and volume distribution
large pulsatile flow in ventricle. Aorta limits pressure variation. Arteriole to capillary makes no pulse flow. Right atrium- very little pressure
pulse dampening and distribution
distribution of arterial blood
distribution and resistance
resistance, lots of smooth muscle- GREATEST P CHANGE
exchange, collection, and capacitance
capacitance function (STORE)
collection of venous blood
How can capillaries withstand so much pressure
Law of LaPlace- TENSION
T=Pr, T is wall tension. small vessels can withstand higher pressures!
doppler flow equation
left ventricle goes where, right ventricle goes where
left goes systemic, right goes pulmonary
types of myocardium in heart walls
longitudinal, circumferential, oblique. this allows for upward pumping.
which ventricle is thinner walled?
loss of pulse pressure occurs where? (greatest pressure change)
2/3 of heart is where In terms of midline?
left and twisted: looking in you will see R ventricle
mitral/bicusupid (L) or tricuspid (R)
aortic and pulmonary
intercalated disks contain
gap junctions, which allow ionic current flow. connexins
formed by connections, myocardial cells function stay as a unit
two major features of the artery
thickness of wall and elasticity- compliance
contraction, emptying go ventricle
relaxation, filling of the ventricle
does the cardiac output change with activity?