Advanced Hemodynamic Monitoring

Question 1

normal value for cardiac index

Answer 1

2.2-4.2 L/min/m2

Question 2

normal central venous pressure

Answer 2

5-12 mm Hg

Question 3

when is measurement of CVP most accurate ?

Answer 3

at end of expiration

Question 4

coronary perfusion pressure

Answer 4

50-120 mm Hg

Question 5

what is roughly equal to central venous oxygen saturation ? value in awake pt?

Answer 5

mixed venous oxygen saturation; 60-80%

Question 6

value for pulmonary artery pressure

Answer 6

15-30/10

Question 7

values for mild, moderate, and severe pulmonary HTN

Answer 7

mild (36-49 mm Hg systolic)
moderate (50-59 mmHg)
severe >60 mm Hg

Question 8

normal value for stroke volume

Answer 8

60-90 mL/beat

Question 9

normal value for stroke volume index

Answer 9

20-65 mL/beat/m2

Question 10

normal value for systemic vascular resistance

Answer 10

700-1200 dynes sec cm -5

Question 11

normal value for central venous O2 saturation (ScvO2)

Answer 11

25-30% below the pt’s SaO2 or 70-75% if the SaO2 is normal

Question 12

responds to changes in blood pressure

Answer 12

baroreceptor reflex

Question 13

when bp is low , hr ____

Answer 13

increases

Question 14

when bp is high, hr ___

Answer 14

decreases

Question 15

responds to changes in blood volume inside the heart

Answer 15

bainbridge reflex

Question 16

what happens to the bainbridge reflex if right atrial pressure increases bc blood volume in the right atrium increases ?

Answer 16

an increased hr and vasodilation (venous pooling in the legs and decreased venous return)

Question 17

what two things will cause an increase in hr?

Answer 17

1. low CVP (thru baroreceptor reflex)

2. high CVP (thru bainbridge reflex)

Question 18

what provides a more accurate interpretation of cardiac output?

Answer 18

cardiac index

Question 19

2 equations for coronary perfusion pressure

Answer 19

1. CPP= DBP-LVEDP

2. CPP= DBP-CVP

Question 20

3 ways to estimate left ventricular diastolic pressure

Answer 20

1. LVEDP =left atrial pressure
2. left atrial pressure= PCWP
3. PCWP= PA diastolic pressure

Question 21

3 equations to estimate CPP

Answer 21

1. CPP= DBP-CVP
2. CPP= DBP-PCWP
3. CPP= DBP- PA diastolic pressure

Question 22

4 steps for the thermodilution technique

Answer 22

1. 10 mL saline is injected to right atrium
2. this cold fluid travel to the PA where it encounters the thermistor on the swan
3. the cold fluid is warmed to a degree
4. the monitor produces a waveform based on how cold the fluid at the thermistor is

Question 23

high cardiac output will cause the thermistor to?

Answer 23

gets cold fast but WARMS UP QUICKLY; total area under the thermodilution curve will be LOWER than normal

Question 24

low cardiac output will cause the thermistor to ?

Answer 24

stay cold for a longer period; total area under the thermodilution curve will be HIGHER than normal

Question 25

a small thermodilution wave indicates?

Answer 25

high cardiac output; decreased area overestimates cardiac output

Question 26

a large thermodilution wave indicates?

Answer 26

low cardiac output; increased area underestimates cardiac output

Question 27

what happens if an anesthetist injected the saline too slowly? >4 seconds

Answer 27

thermodilution curve would be larger than normal bc blood at the thermistor would stay cold for a longer period which means the cardiac output reading would be underestimated

Question 28

pt has a right to left intracardiac shunt. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?

Answer 28

overestimation

Question 29

pt has a left to right intracardiac shunt. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?

Answer 29

overestimation

Question 30

pt has a tricuspid regurgitation. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?

Answer 30

underestimation

Question 31

refers to oxygen saturation of blood taken from the superior vena cava

Answer 31

central venous O2 saturation (ScvO2)

Question 32

where is a mixed venous sample taken from in a pulmonary artery catheter?

Answer 32

distal tip

Question 33

mixing of blood in a mixed venous samples comes from what three places?

Answer 33

SVC, IVC, coronary sinus