SFP: cardiovascular overview Flashcards
Which side of the heart pumps to the lungs?
Right
Which side of the heart pumps to the system?
Left
What are considered the elastic vessels?
The aorta and major arteries
What are considered the resistance vessels?
Arterioles and metarterioles
Where does fluid and nutrient exchange occur?
Capillaries
What does it mean that organs run in a parallel circuit?
They receive blood from the arterial side, and return blood to the venous side
What are the advantages of parallel circuits?
We can shut blood off to certain organs and redirect it to where it is needed.
Organs receive blood of the same composition and can return waste products to the venous side. Total resistance is reduced in the heart.
What is the typical oxygen content in men and women?
15 g/mL and 13 g/mL respectively
__ g of hemoglobin combines with __ mL of O2
1; 1.34
Blood volume is about __% of our mass.
7
2/3 of the blood in our body can be found in?
Veins, venules, and venous sinuses
Describe the general flow of blood through the heart.
Heart sounds come from…
Valves closing
What is meant by the term incompetent valves?
They allow regurgitation
What is meant by stenotic valves?
They require extra work to open
Which side of the heart has low pressure, and which has high pressure?
Right has low pressure, left has high pressure
What is the difference between systole and diastole?
Systole involves contraction of the muscle and ejection of blood, while diastole involves relaxing of the muscle and filling with blood
What is isovolumetric contraction?
What is isovolumetric relaxation?
What is end diastolic volume?
Blood has filled the ventricle and contraction is about to start; this is as big as the ventricle will be, and the volume of the ventricle is the EDV
What is end systolic volume?
Blood has left the ventricle, contraction has occurred, and relaxation is about to begin again; this is as small as the ventricle will be and the volume of the ventricle is the ESV
Do the right and left ventricles have the same contraction pattern?
No
A normal heart weight between __ and __ grams?
200-425
On X-ray, cardiac silhouette is about __% of the thoracic cavity?
50%
What acts as the intrinsic pacemaker of the heart?
SA node
What equation do we use to measure pump performance?
CO = SV x HR
What is stroke volume?
Volume of blood ejected from a ventricle in one beat
What is cardiac output?
The volume of blood ejected from a ventricle over one minute
Describe the relationship between SV and CO in the left and right heart.
They must be the same over time
What is a normal cardiac index?
2.5-4 L/min/m2
What is ejection fraction?
The percentage of blood ejected with every beat; measured by SV/EDV
What is the Fick technique?
A method of measuring cardiac output that requires sampling of arterial and venous blood as well as a measurement of oxygen consumption
What is the Fick equation?
Q = VO2/ (CaO2 – CvO2)
What is a Swan-Ganz catheter?
A balloon catheter that can find wedge pressure, can sample venous blood
When is the ventricle largest? When is it smallest?
EDV; ESV
When is the atrium largest? When is it smallest?
ESV; EDV
How is distribution of cardiac output per organ determined?
It is dependent on metabolic needs, which can change by condition. It is regulated by the ANS
What are the two circulations received by the lungs?
Pulmonary (right) and bronchial (left)
Describe the basic functioning of the aorta and pulmonary artery.
They receive a systolic bolus and recoil upon valves closing to propel the blood. This allows continuous flow to the tissues
What is compliance in terms of arteries?
Energy of pulse is stored and released into the system to allow for continuous flow. If vessels were noncompliant, flow would be intermittent
How do we calculate mean arterial pressure?
MAP = (SBP + (2DBP))/3
What is considered the ‘driving pressure’?
MAP
How do we calculate flow in vessels?
F(Q) = (change in pressure)/(radius)
How do we calculate total peripheral resistance?
SVR = (MAP-RAP)/CO x 80
How do we calculate pulmonary vascular resistance?
PVR = (PApressure-LAP)/CO x 80
What is Poiseuille’s law?
R = 8nL/(πr^4) where n is blood viscosity, L is length of the vessel, and r is the radius of the vessel
