Advanced Hemodynamic Monitoring Flashcards
normal value for cardiac index
2.2-4.2 L/min/m2
normal central venous pressure
5-12 mm Hg
when is measurement of CVP most accurate ?
at end of expiration
coronary perfusion pressure
50-120 mm Hg
what is roughly equal to central venous oxygen saturation ? value in awake pt?
mixed venous oxygen saturation; 60-80%
value for pulmonary artery pressure
15-30/10
values for mild, moderate, and severe pulmonary HTN
mild (36-49 mm Hg systolic)
moderate (50-59 mmHg)
severe >60 mm Hg
normal value for stroke volume
60-90 mL/beat
normal value for stroke volume index
20-65 mL/beat/m2
normal value for systemic vascular resistance
700-1200 dynes sec cm -5
normal value for central venous O2 saturation (ScvO2)
25-30% below the pt’s SaO2 or 70-75% if the SaO2 is normal
responds to changes in blood pressure
baroreceptor reflex
when bp is low , hr ____
increases
when bp is high, hr ___
decreases
responds to changes in blood volume inside the heart
bainbridge reflex
what happens to the bainbridge reflex if right atrial pressure increases bc blood volume in the right atrium increases ?
an increased hr and vasodilation (venous pooling in the legs and decreased venous return)
what two things will cause an increase in hr?
- low CVP (thru baroreceptor reflex)
2. high CVP (thru bainbridge reflex)
what provides a more accurate interpretation of cardiac output?
cardiac index
2 equations for coronary perfusion pressure
- CPP= DBP-LVEDP
2. CPP= DBP-CVP
3 ways to estimate left ventricular diastolic pressure
- LVEDP =left atrial pressure
- left atrial pressure= PCWP
- PCWP= PA diastolic pressure
3 equations to estimate CPP
- CPP= DBP-CVP
- CPP= DBP-PCWP
- CPP= DBP- PA diastolic pressure
4 steps for the thermodilution technique
- 10 mL saline is injected to right atrium
- this cold fluid travel to the PA where it encounters the thermistor on the swan
- the cold fluid is warmed to a degree
- the monitor produces a waveform based on how cold the fluid at the thermistor is
high cardiac output will cause the thermistor to?
gets cold fast but WARMS UP QUICKLY; total area under the thermodilution curve will be LOWER than normal
low cardiac output will cause the thermistor to ?
stay cold for a longer period; total area under the thermodilution curve will be HIGHER than normal
a small thermodilution wave indicates?
high cardiac output; decreased area overestimates cardiac output
a large thermodilution wave indicates?
low cardiac output; increased area underestimates cardiac output
what happens if an anesthetist injected the saline too slowly? >4 seconds
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
pt has a right to left intracardiac shunt. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?
overestimation
pt has a left to right intracardiac shunt. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?
overestimation
pt has a tricuspid regurgitation. would thermodilution in this pt lead to overestimation or underestimation of cardiac output?
underestimation
refers to oxygen saturation of blood taken from the superior vena cava
central venous O2 saturation (ScvO2)
where is a mixed venous sample taken from in a pulmonary artery catheter?
distal tip
mixing of blood in a mixed venous samples comes from what three places?
SVC, IVC, coronary sinus
