Hemodynamics

Question 1

Cardiac output

Answer 1

-Normal is 4-8L per minute

Question 2

Cardiac Index

Answer 2

-Normal is 2.5-5L/min/m^2

-Cardiac index is a more meaningful indication of the heart
-Takes in to account the body surface area of the patient

Question 3

Preload

Answer 3

-The volume/pressure in the ventricle at the end of diastole after the AV node closes

-Right atrial pressure or CVP measure right ventricular preload
-PAOP measures left ventricular preload

Question 4

Afterload

Answer 4

-The pressure against which the ventricle must pump to open to pulmonic or aortic valve

-As afterload increased, cardiac output and stroke volume decrease

Question 5

Acute Mitral Valve Insufficiency

Answer 5

-PA catheter placed to measure PAOP
-When the balloon is inflated there will be a “Giant V-Wave” on the PAOP tracing
-PAOP is read at the A-Wave NOT the V-Wave

If you see “giant V-Waves” on the exam IMMEDIATLY think mitral valve insufficiency

Question 6

Square Wave Test (Dynamic Response)

Answer 6

-Used to assess the accuracy of hemodynamic monitoring

-WHEN?:
After insertion
Beginning of shift
After zeroing
When reading is questionable

Question 7

Square Wave Test OVERdampened

Answer 7

-False LOW systolic pressure
-False HIGH diastolic pressure

-May be due to a blood clot, loose connections, loss of air in pressure bag, kink in tubing

Question 8

Square Wave Test UNDERdampened

Answer 8

-False HIGH systolic pressure
-False LOW diastolic pressure

-May be due to pinpoint air bubbles, add-on tubing, or a defective transducer