Physiology - Cardiac output Flashcards
what is cardiac output?
a. volume of blood pumped by both ventricles in one minute
b. volume of blood pumped by the left ventricle in one minute
c. volume of blood pumped by the left ventricle per contraction
b.volume of blood pumped by the left ventricle in one minute
the biggest changes to cardiac output can be attributed to..
a. Stroke volume
b. heart rate
b.heart rate
what effect does the sympathetic NS have on HR
a. increase
b. decrease
a.increase
+ve chronotropic effect
activation of B1 receptors by the SNS leads to opening of which channels
a. sodium
b. calcium L
d. potassium
b.calcium L
what affect does the opening of calcium l channels by activation of the B1 receptor have on the AP graph
a. decreases slope of prepotential, reaches firing level slower
b. increases slope of prepotential, reaches firing level slower
c. decreases slope of prepotential, reaches firing level faster
d. increases slope of prepotential, reaches firing level faster
d. increases slope of prepotential, reaches firing level faster
where does the right sympathetic chain supply
a. SAN
b. AVN
c. left ventricle
d. right ventricle
b.AVN
where does the left sympathetic chain supply
a. SAN
b. AVN
c. left ventricle
d. right ventricle
a.SAN
which receptor activated by the parasympathetic NS opens K+ channels and slows opening of ca2+ channels ?
a. Mu
b. Ka
c. Icl
d. B2
e. M2
e.M2
altering cardiac output dependent on initial length of muscle fibre is known as
a. frank starling relationship
b. homeometric regulation
c. heterometric regulation
c.heterometric regulation
altering cardiac output independent on initial length of muscle fibre is known as
a. frank starling relationship
b. homeometric regulation
c. heterometric regulation
b.homeometric regulation
what does the frank starling relationship state
a. stroke volume(so CO) is dependent on degree of stretch on ventricular walls
b. stroke volume is dependent on stretch of atrial walls
c. heart rate is dependent on stretch of ventricular walls
a.stroke volume(so CO) is dependent on degree of stretch on ventricular walls
increase in which volume stretches the ventricular walls increasing stroke volume?
a. systolic end vol
b. end diastolic volume
c. start diastolic volume
d. start systolic volume
b.end diastolic volume
which direction does sympathetic stimulation shift the frank starling curve?
a. up
b. down and right
c. left and up
d. down
c.left and up
positive inotropic effect
which direction does sympathetic stimulation shift the frank starling curve?
a. up
b. down and right
c. left and up
d. down
e. no change
e.no change
no effect on ventricles
what affect do catecholamines eg adrenaline and noradrenaline have on heart rate?
a. amplify B1 effects
b. decrease B1 effects
c. no effects
d. increase M2 effects
a.amplify B1 effects
increase heart rate
true or false arterial content of oxygen can be dtermined from any arterial sample
a. true
b. false
a.true
doesnt vary from artery to artery
true or false venous content of oxygen can be dtermined from any vein sample
a. true
b. false
b.false
catheter inserted into forearm and guided up to the pulmonary artery
what is the correct equation for CO ?
a. A-V x VO2
b. A+V / VO2
c. A-V /VO2
d. VO2/ a-V
d.VO2/ a-V
in the indicator method of CO measurement where is the known quantity of dye injected?
a. left hand side of the heart
b. SVC
c. Pulmonary artery
d. forearm
e. right hand of the heart
e.right hand of the heart
then arterial blood sampled with dye conc monitored over next 30-60 seconds using spectrophotometer
when cold saline is used instead of dye where is it injected?
a. left hand side of the heart
b. SVC
c. Pulmonary artery
d. right atria
e. right hand of the heart
d.right atria
what measures the cold saline after injection to the rught atria?
a. spectrophotometer
b. thermometre
c. thermistor
c.thermistor
patient with insufficient peripheral perfusion despite normal blood volume, sufficient filling and intact compensatory mechanisms
what is the most likely cause?
a. cardiac tamponade
b. valvular problems
c. coronary artery disease
c.coronary artery disease
Renal blood flow decrease, pulmonary oedema, and ankle swelling are systemic effects of which condition?
a. MI
b. heart failure
c. atrial fibrillation
d. ventricular dystrophy
b.heart failure
