ECMO Specialist Crouse Adult 2015 Flashcards
During VA ECMO what should we expect in regard to the pulse pressure?
- Dampened Arterial Waveform
- Pulse Pressure 10 mmHg
Anything that changes the volume status of the patient will change the ratio of pump to heart flow, such as ?
IV
Urine
Edema
Hemoconcentrator
CVP (bladder pressure) =
Preload to the pump
How does the mixing cloud happen?
Mixed Arterial Blood Gas
Blood flow from the heart crashes with Blood from from the arterial cannula.
Minor cardiac contribution with High flow rate through femoral cannulation would result in a mixing cloud at what region ?
Ascending Aorta
Moderate cardiac contribution with Moderate Flow Rate through femoral cannulation would result in a mixing cloud at what region ?
Aortic Arch
Large cardiac contribution with minimal Flow Rate through femoral cannulation would result in a mixing cloud at what region ?
Abdominal Aorta
To change the PaO2 what knob would you adjust ?
FiO2
more true for VA than VV
To change the PCO2 what knob would you adjust ?
Sweep gas rate
more true for VA than VV
To change the SVO2 what knob would you adjust ?
Pump Flow
more true for VA than VV
How would you evaluate adequacy of perfusion with a blood gas?
Compare PreOxygenator with Patient ABG
How would you evaluate Oxygenator Function with a blood gas?
Compare PreOxygenator with Post Oxygenator
How would you evaluate Pulmonary contribution with a blood gas?
Compare PostOxygenator with Patient ABG
Evaluate Oxygenator
Function:
Pre = PCO2 50 PO2 45 Post = PCO2 49 PO2 350
Increase Sweep
Evaluate Oxygenator
Function:
Pre = PCO2 50 PO2 35 Post = PCO2 20 PO2 350
Decrease Sweep
Evaluate Oxygenator
Function:
Pre = PCO2 50 PO2 35 Post = PCO2 20 PO2 90
Increase FiO2
Evaluate Adequacy of Perfusion:
Pre= PCO2 50 PO2 35 SAT 65% Post= PCO2 40 PO2 100 SAT 100%
Perfect
Evaluate Adequacy of Perfusion:
Pre= PCO2 45 PO2 35 SAT 65% Post= PCO2 60 PO2 100 SAT 100%
More Ventilation
Increase Sweep
Evaluate Adequacy of Perfusion:
Pre= PCO2 35 PO2 35 SAT 65% Post= PCO2 25 PO2 100 SAT 100%
Less Ventilation
Decrease Sweep
Evaluate Adequacy of Perfusion:
Pre= PCO2 45 PO2 30 SAT 60% Post= PCO2 35 PO2 60 SAT 85%
More Oxygenation
Increase FiO2
Evaluate Adequacy of Perfusion:
Pre= PCO2 55 PO2 28
Pt ABG = PCO2 35 PO2 100
More Blood Flow
What is the measure of adequacy of perfusion ?
Mixed Venous Saturation (SVO2)
Under what circumstances is the SpreO2 NOT a true SVO2 ?
- VV Recirculation
- AV Shunts
- Circuit Shunts (Hemoncentrator in circuit)
- Patient Shunts (LV Vent)
To initiate cannulation what 3 things must be accomplished ?
- Anesthetize
- Paralyze
- Heparinize
What is the patient Heparin loading dose?
100 u / Kg
Target metric for Heparin dosing ?
PTT 1.5 - 2 greater than normal
ACT 160 - 240 sec
ACT targets are based on patient acuity and blood flow in the circuit.
ACT for Bleeding or high flows =
ACT for Not bleeding or low flows =
ACT for Bleeding or high flows = (160 - 200)
ACT for Not bleeding or low flows =(200 - 240)
what are the 4 Heparin dosing steps ?
1.) Check ACT before initiation
2.) Turn Heparin GTT ON once
heparin falls into range.
3.) Start GTT at 35-50 u/kg/hr
4.) Titrate GTT to maintain
target ACT.
In order to provide flow to the pump, the CVP must stay positive normally above what?
8 - 12
VLP =
CVP + Height of the table
before flow starts
If the VLP is dropping quickly . . . . . . . What is going to happend ?
The pump is about to stop pumping.
What will indicate if the RA collapses onto the cannula and blood flow stops?
Chatter in the venous line
ALP =
ABP + 200 mmHg
What 4 factors dictate ALP ?
- Cannula size
- Cannula position
- Patients BP
- Pump Flow
What is the target Pump Flows?
2.0 -3.0 CI ( 3.5 - 5.0 LPM)
My patients PaO2 is 69%, we are failing to Oxygenate. What are the 3 Hallmarks of a failing oxygenator?
1.) Widening pre-post pressures
(consider flow & SVR variations)
2.) Decreased CO2 clearence
(consider sweep gas flow variations)
3.) Decreased Oxygenaion
(consider FiO2 variations)
What is happening if i notice the water in the water bath is colored ?
What will happen i f water pressure exceeds blood pressure?
-Blood to water leak
Turn off the water bath to reduce water pressure.
Water will leak into the blood = hemolysis & sepsis
VA ECMO trial Off sequence ?
- ) Increase Vent settings
- ) Turn off oxygenator sweep gas
- ) Clamp cannulas, flow through bridge
- ) Check Pt & circuit ACT Q 20 min
- ) Flash cannulas Q 20 min
- ) Check SVO2 to assess pt during flash
VV ECMO trial Off sequence ?
- ) Increase Vent settings
- ) Turn off oxygenator sweep gas
- ) Check ACT Q 60 min
- ) Check SVO2 to assess pt continuously
