Introduction Flashcards
what is the blood pressure in the right atrium?
5/0 mmHg
what is the blood pressure in the right ventricle?
25/0 mmHg
what is the blood pressure in the left atrium?
10/5 mmHg
what is the blood pressure in the left ventricle?
120/5 mmHg
what is the blood pressure in the pulmonary artery?
25/10 mmHg
what is the blood pressure in the aortic arch?
120/80 mmHg
what is cardiac output?
volume of blood pumped over some unit of time
what units are usually assigned to cardiac output?
liters/minute
what is the cardiac output formula?
cardiac output=heart rate x stroke volume
CO=HRxSV
what is inotropy?
contractile state of the heart
what is chronotropy?
speed of the heart
what is dromotropy?
speed of conduction of an electrical impulse, especially through the AV node
what is lusitropy?
property relating to the speed of myocardial relaxation
what does higher sympathetic tone lead to?
faster heart rate
positive inotropy
positive chronotropy
increased vascular tone
what does higher parasympathetic tone lead to?
slower heart rate
negative chronotrope
negative dromotrope
what is the equation for resistance?
[mean] driving pressure/flow rate
what is the equation for total peripheral resistance?
(mean aortic pressure - right atrial pressure)/cardiac output
TPR=(MAP-RAP)/CO
what is the equation for ejection fraction?
EF=(end diastolic volume - end systolic volume)/end diastolic volume
EF=(EDV-ESV)/EDV
what can ventricular systole be subdivided into?
electrical systole
mechanical systole
what can ventricular diastole be subdivided into?
electrical diastole
mechanical diastole
what is the law of laplace important for?
ventricular wall stress
trigger for hypertrophy
what is afterload?
sum total of forces that must be overcome to eject blood
central mechanisms maintain central pressure by controlling ___________________________ and ____________________________
total peripheral resistance (TPR)
cardiac output (CO)
what does poiseuille’s equation determine?
resistance
what is resistance primarily altered by?
arterial vascular radius
arterial vasoconstriction
what is compliance?
volume of blood a vessel can hold at a given pressure
what controls cardiac output?
compliance and vascular volume
what is the equation for the law of laplace?
sigma (wall stress) = pressure x radius of chamber/2 x thickness of wall
what is sometimes considered a surrogate to afterload?
blood pressure
how do central mechanisms maintain central pressure?
controlling total peripheral resistance and cardiac output
what is compliance?
volume a blood vessel can hold at a given time
what does constriction of compliance vessels do?
decreases compliance of entire circulation
venous pressure increases
what controls cardiac ouput?
compliance and vascular volume
____________ determines flow distribution
____________ determines volume distribution
resistance
compliance
