Invasive Monitoring Flashcards
What is CVP and normal range?
Central venous pressure (right side preload)
2-6 mmHg
Increased CVP (2- 6 mmHg norm) can be caused by :
Fluid overload
Cardiac tamponade
R heart dysfunction / infarct
PEEP
L Sided HF
COPD
Tricuspid insufficiency
Pulmonary HTN
Decreased CVP can be caused by:
Dehydration
Volume loss (fluid or blood)
Venodilation
R atrial pressures
Arterial line
Direct and real-time systolic and diastolic pressure and MAP
What is this?
Normal art-line waveform
What is this?
Overdamped art line waveform
What is this?
Underdamped art line
Formula For CO
HR x SV
Stroke volume variance (SVV)
Another way to measure preload. Norma range under 13
(High and dry, number above 13 has a low preload may need more volume)
Limitations to FloTrac SVV
Spontaneous breathing
Open chest
Arrythmias
(Can use passive leg raise 45 degrees to measure if pt needs fluid. “Mini-bolus”)
Swan/PA Catheter
In the vena cava, right atrium, right ventricle, resting in the pulmonary artery. Multiple ports along the cath. Gives CVP/RAP, PAP, PCWP, and CO/CI
What is PAP and normal range?
Pulmonary artery pressure
Systolic: 15 - 25 mmHg
Diastolic: 8 - 15 mmHg
What can cause an increase in PAP?
Atrial septal defect
Pulmonary HTN
LV failure
Mitral stenosis/regurgitation
What is PCWP?
Pulmonary Capillary Wedge Pressure.
Measured by inflating a small balloon at the tip of the PA Catheter. Gives and indirect measurement of preload on the left side of the heart.
Normal range for PCWP?
8-12 mmHg
Reasons for increased PCWP value?
Fluid overload
Aortic stenosis/regurgitation
Mitrial stenosis
LV failure
Tamponade
Constrictive Pericarditis
Reasons for decreased PCWP?
Hypovolemia
Vasodilation
Do you leave the balloon inflated for PCWP?
No, you inflate, get your measurements, then deflate. Leaving it inflated blocks part of the pulmomary artery.
Cardiac output/ cardiac index (w/ PA Cath)
Can be continuous or intermittent
Normal range for SVR
800-1200 dynes/sec/cm^5
What causes low SVR values?
Below 800, vessels are very dialated, so there is little resistance. Low BP to be expected
What causes elevated SVR?
Greater than 1200 dynes/sec/cm^5; vessels are very “clamped down”; expected elevated bp; increases workload of the heart d/t the heart beating against it. Can affect CO
Equation to calculate SVR
[(MAP - CVP) / CO] * 80
Normal PCWP range
8 - 12 mmHg
