Ch. 9 Cardiac Monitoring (Test 2) Flashcards
Pulmonary artery pressure (PAP) is an important measurement in the care of critically ill pts with sepsis, ARDS, pulmonary edema, MI
know
What is normal PvO2?
35 to 45 mm Hg
PvO2 reflect
tissue oxygenation
If PvO2 level drops after intiation of or increase of PEEP then what has occurred?
A decrease in tissue oxygenation has occurred, caused by a drop in QT b/c of PEEP. PEEP should be decreased to maintain an adequate PvO2
Normal systolic PAP is
Normal diastolic PAP
Normal mean PAP
15 to 30 mm Hg
5 to 15 mm Hg
10 to 20 mm Hg
What are some conditions that increase PAP (3)
(1) Pulmonary hypertension (resulting from hypercapnia, acidemia, or hypoxemia, for example)
(2) Mitral valve stenosis
(3) Left ventricular failure
What are some conditions that decrease PAP?
(1) Decreased pulmonary vascular resistance (pulmonary vasodilation); caused by improved oxygenation, for example
(2) Decreased blood volume
When the balloon at the distal end of the catheter is inflated, it wedges in a branch of the pulmonary artery, blocking blood flow from the right side of the heart. The transducer measures the back pressure through the pulmonary circulation, which is equal to pressure in the left atrium and to the……..
The is called the and is measuring what?
left ventricular end- diastolic pressure (LVEDP)
Pulmonary capillary wedge pressure (PCWP)
PCPW is a measurement of the pressure of which sid eof the heart?
left side
The ballon should not be inflanted any longer than __ to __ seconds because blood flow obstruction for any longer may cause what?
15 to 20 seconds
pulmonary infarction
What is the normal PCWP
5 to 10 mm Hg
PCWP greater than 18 mm Hg indicates what?
Cardiogenic pulmonary edema
PCWP is ___________ in patients with cardiogenic pulmonary edema and is _________ in patients with noncardiogenic pulmonary edema.
Elevated
normal
What can cause a “damped” waveform in a A-line
- Occlusion of the catheter tip by a clot
- Catheter tip resting against the wall of the vessel
- clot in the transducer
- air bubbles in the line
How to correct: Occlusion of the catheter tip by a clot
correct by aspirating the clot and flushing with heparinized saline.
How to correct: Catheter tip resting against the wall of the vessel
correct by repositioning
catheter while observing waveform.
How to correct: Clot in transducer or stopcock
correct by flushing system; if no improvement is seen in the waveform tracing, disconnect the transducer and change the stopcock.
How to correct:Air bubbles in the line
correct by disconnecting transducer and flushing out air bubbles.
How to correct:Improper calibration:
correct by recalibration of monitor and strain gauge.
How to correct: Improper transducer position
correct by ensuring the transducer is kept at the level of the patient’s heart. If the transducer is placed below the level of the heart, the pressure reading will read higher than the actual pressure. If the transducer is placed above the level of the heart, the pressure reading will read lower than the actual pressure.
No pressure reading; causes include: Improper scale selection: How to correct
correct by selecting appropriate scale.
How to correct: Transducer not open to catheter:
correct by checking system and making sure the transducer is open to the catheter.
Systemic vascular resistance (SVR) is a measurement of the resistance that the left ventricle must overcome to eject its volume of blood. This is know as _________
afterload
What is normal SVR
900 x 1400 dyne x seconds x cm-5