ECMO Circuits and Components Flashcards
What are the basic components of all ECMO circuits?
Cannulas Tubing/Pump boot Bladder/Reservoir Blood Pump Oxygenator Heat Exchanger
Additional Components of an ECMO Circuit
Water heater/cooler Pressure monitoring Transducers Circuit Bridge Blood Monitoring Air detector
Where is the pressure monitor?
At bladder
Where does the heparin go in in the ECMO circuit?
Heparin going in before the membrane
What are the 3 cannula selection types?
Arterial
Venous
Dual Lumen (VV cannula)
0-3 kg: Flow
200 cc/kg
3-10 kg: Flow
150 cc/kg
10-15 kg: Flow
125 cc/kg
15-30 kg: Flow
100 cc/kg
> 30 kg
75 cc/kg
> 55 kg
65 cc/kg
V-A ECMO Target Flows
Neonate: 100-150 cc/kg/min
Pediatric: 75-100 cc/kg/min
Adult: 50-75 cc/kg/min
V-V ECMO Target Flows
Neonate: 100-120 cc/kg/min
Pediatric: 90-100 cc/kg/min
Adult: 75-90 cc/kg/min
What are the goals of the arterial cannula selection?
Make your surgeon happy
Have a large enough cannula to minimize pressure drop
Minimize shear stress
Maintain laminar flow
What are the goals of the venous cannula selection?
Make your surgeon happy
Have a large enough venous cannula to gravity drain the amount of blood flow that is required (but small enough to fit)
Flow with pediatrics is ______ based.
weight (cc/kg)
Flow with adults is usually ______.
indexed (L/min/m2)
What is the aim of the arterial cannula?
Utilize the smallest cannula w/ the highest flow rate
Arterial Cannula: Do not exceed pressure drop greater than what?
> 100 mmHg
When is the critical velocity reached with arterial cannula?
Reached when laminar flow becomes turbulent (Reynold’s number)
Higher pressures = higher ________ = hemolysis = BAD
shear stress
What is the aim of the venous cannula?
Drain the patient with the smallest cannula.
What should you be aware of the in regard to venous cannula?
Be aware of the cannulation site