Hemodynamics Flashcards
What is an A-line used for? What will you see on the wave form?
Continuous BP monitoring & ABG’s.
You will see a dicrotic notch.
What is pulses paradoxus?
Diminished amplitude on inspiration in SBP greater than 10. Suggestive of cardiac tamponade, pericarditis or lung disease.
What is Pulsus Alternans?
Regular pattern of pulse amplitude changes that alternate between stronger and weaker beats. Suggestive of end-stage left ventricular heart failure.
What is a PA Catheter (Swan Gangze) used for?
C.O, CI, & fluid balance
CVP measures right side of heart
PAOP/PAWP measures left side of heart
SVR measures how well your arteries can squeeze
What are complications of PA catheters?
- Air embolus, infection, thrombosis
- PA rupture causing pulmonary infarction
- Ventricular irritation when cath migrates back into RV or loops. Can cause VT.
- Catheter wedges permanently, shows flat PA waveform. Risk of infarct after 3 min.
NORMAL VALUES
- CVP
- PAP
- PAOP
- CVP 2-5mm Hg
- PAP 20-30/5-10
- PAOP 5-12
NORMAL VALUES
- SVO2 (where do we measure it from?)
- SCVO2 (where do we measure it from?)
- CI
- SVO2 60-75% (from A-line)
- SCVO2 70-80% (from central line)
- CI 2.2-4.0L
NORMAL VALUES
- SVR
- PVR
- SV
- SV index
- SVR 800-1400
- PVR 100-250
- SV 60 - 70mL
- SV index 40-50
What measures pre-load?
CVP & PAOP
What measures after load?
SVR
What measures contractility?
C.O & SV
What is cardiac index?
Cardiac output adjusted for body size
What is SVI?
Stroke volume adjusted for body size
What is after load?
resistance against which ventricle pumps
What does SVR measure?
systemic vascular resistance measures left ventricular after load.
What does PVR measure?
Pulmonary vascular resistance against which the right ventricle works.
How to calculate CI?
CO/BSA
What is the proximal injectate port on the PA catheter used for?
Infusions up to 492 ml/hr. DO NOT put titrated meds in this port.
What is the PA distal port used for?
Measuring mixed venous blood. DO NOT infuse meds.
What is the RA port used for in the PA catheter?
HIGH VOLUME infusion.
What is the RV port used for in the PA catheter?
LOW VOLUME infusions less than 50ml/hr
How long do you wedge for?
No longer than 15 seconds
How do you deflate the PA wedge?
Passive deflation.
How many ml of air do you inflate the wedge balloon with?
No more than 1.5ml. Only use 1.5ml syringe supplied with catheter.
What is square wave testing?
Reflects the accuracy of the pressure and waveform. Should use fast flush and observe a square wave.
What happens to CO and SVR during cardiogenic shock?
CO goes down.
SVR goes up.
What happens to CO, central pressures and SVR during hypovolemic shock?
CO goes down.
Central pressures go down
SVR goes up.
What happens to CO, central pressures and SVR during septic shock?
CO goes UP.
Central pressures go down.
SVR goes down.
In what order do we tx hemodynamic instability?
- Preload (CVP & PAWP)
- Afterload (SVR, PVR)
- Contractility (CO, SV)
Your patient is in heart failure and his CVP is 8. What are some possible medications you can administer to decrease preload?
Nitro
Nipride
Furosemide
Mantiol
Your patient is in hypovolemic shock. What can you administer to increase preload?
Administer Colloids, crystalloids, blood, hetastarch, antiarrhythmics.
Your patient is in hypovolemic shock. What can you administer to decrease after load (SVR)?
Nitro
Alpha Adrenergic Blockers
CCB
Your patient is in early septic shock. What can you administer to increase after load (SVR)?
Epi, norepi
Dopamine
Your patient is hypoxic and a PVR of 350 (100-250). What are possible medications for this patient?
- Inotropic agents (Digoxin) to increase force of contraction.
- Vasodilators (Procardia, Cardizem). Lowers pulmonary BP and improves pumping ability of R side of heart.
- Epoprostenol (Flolan). Dilates pulmonary arteries.
- Diuretics (lasix, aldactone). Removes fluid/reduces swelling, improves ventilation.
