EDECMO 20 – The Golden Hour & the Rule of 3’s: Optimizing the Critical First Hour on Heart-Lung Bypass


Upcoming Conferences:

  1. SMACC 2015: June 23-26, 2015. The biggest and baddest critical care conference of the year is in Chicago this year.
  2. Essentials of Emergency Medicine 2015. October 13-15, 2015. The Big Show. In Vegas. At the Cosmopolitan.
  3. Reanimate San Diego. February 25-26, 2016. The essentials of ECMO in 2 glorious days. Here is a sneak peak at the Reanimate 2016 Promo Video.

Flipped Classroom SMACC ECMO Workshop 2015

For those taking the upcoming ECMO courses with us, download both of these 2 attachments. The first is a diagram of a traditional ECMO circuit – its nice to print this out and follow along. Not every circuit is the same and we have ours custom built by Maquet.  The second is a self-study course.  While it isn’t necessary to review these before our workshop, it will really put you ahead of the game and we focus more on procedures.

Custom Maquet Circuit

Figure 1. The Custom Maquet ECMO Circuit

Study Guide

Screen Shot 2015-04-04 at 11.04.36 PM

Review of the 3 stages of ECPR

  1. STAGE 1: Placement of any commercially available vascular catheter in the femoral vein and femoral artery
  2. STAGE 2: Replacement of each catheter with ECMO cannulae. Checkout EDECMO 5: Cognitive Task Management for ED ECMO Stages 1 and 2. Also, we learned several cannulation pearls from Stephen Bernard in EDECMO 14 Part 1 and Part 2
  3. STAGE 3: Initiation of Total Heart Lung Bypass

ECMO Circuit Setup:

  1. Plug in the machine and power-on the heater-cooler and the Rotaflow console.
  2. Unpackage the circuit and hold it up to orient yourself.
  3. Mounting the Rotaflow Pump to the Pump Drive

    Mounting the Rotaflow Pump to the Pump Drive

    Attach the Oxygenator to the bracket and the pump to the pump-drive; hang the distal ends of the circuit (the tubes that will connect to the patient) from the IV pole.

  4. Apply ultrasonic contact cream to the flow probe contact site
  5. Remove and DISCARD the yellow de-airing exit port cap on the top of the oxygenator.
  6. Connect the water lines from the heater-cooler to the Quadrox Oxygenator & open the stopcocks.
  7. “Run the circuit”, making sure that the recirculation bridge is OPEN, arterial and venous tubing is CLAMPED, rapid-prime tubes are CLAMPED, both of the blood sampling “pig tail” stopcocks are CLOSED.
  8. PRIME the circuit:  Priming the Circuit: Filling the ECMO circuit (tubing, pump, oxygenator) with crystalloid priming solution (ie Isolyte), adding 2,500 units of heparin to each 1-liter bag of priming solution.  We discuss the finer details of this with Greg Griffin, the Chief Perfusionist at the University of North Carolina, Chapel Hill in EDECMO 8.
    1. squeeze all air out of prime bag INTO the circuit and then hang those bags from the IV pole.
    2. Open the ratchet clamps: the circuit will fill (prime) by gravity.
  9. Connect the Oxygen supply line (from Oxygen tank) to the Oxygen inlet port on the oxygenator
  10. De-air the circuit:
    1. Remove the patient-lines that are hanging from the IV pole and drop them below the fluid level of the IV bags to prime them. ratchet-clamp them closed. Now the entire circuit has been primed.
    2. Open the recirculation bridge and briefly increase the RPM on the Rotaflow Console until the pump is running at 4LPM for 15 seconds. This will de-air the circuit as air is release from the de-ar exit port on the Oxygenator.  ***Some air may still be trapped in the pump though. So…
    3. Turn the RPM on the Rotaflow console to zero. Allow any air in the pump head to flow into the PVC tubing between the pump head and the oxygenator and then return the RPM to 4LPM to complete the de-airing process.
  11. Calibrate the flow-probe: Reduce pump speed to zero RPM, clamp off the recirculation bridge and “ZERO” the flow probe by pushing the “ZERO” button for a few seconds. The console will beep.

Initiation of Total Heart Lung Bypass (STAGE 3)

Maquet-Circuit-mockup.001So you’ve cannulated your patient while your ECMO-nurse has primed the circuit with crystalloid.  Connect the venous and arterial PVC lines from the circuit to the ECMO cannulas in the patient. And since this is STAGE 3, we’ve established the EDECMO “Rule of 3’s.”  There are 3 things you need remember before, during, and after you’ve initiated heart-lung bypass.

A.  3 Critical First Steps BEFORE initiating bypass:

  1. Heparinize the patient = 5,000 units IV bolus
    1. Heparin 2,500 units in each liter of priming solution
    2. Bioline coating
    3. ACT > 200 seconds
  2. Attach O2 source (@ 4-6 LPM) to the Oxygenator
  3. No open central lines (CVP, Swan-Ganz, etc).

CLOSE the Recirculation Bridge and OPEN the venous and arterial ratchet clamps. Turn up the RPM on the Rotaflow console. Your patient is on heart-lung bypass.

B.  3 Critical things to confirm JUST AFTER your patient is on bypass:

  1. The arterial line should have bright red (oxygenated) blood and the venous line should be dark-red.
    1. IF you see BRIGHT-BRIGHT, you’ve incorrectly placed both cannulas in the same vessel.
    2. If you see DARK-DARK, there is a problem with the oxygenator. Confirm your O2 supply to the oxygenator.
  2. Your cannulas are secured to the skin with suture and tape.
  3. The recirculation bridge is CLOSED.

C.  3 Critical Values to Optimize ECMO

1. Optimize Blood Flow:

  • Establish the MAXIMUM blood flow (LPM) at the lowest RPM. GOAL = 60 ml/kg
  • Increase the RPM on the Rotaflow console until:
    1. Any further increases in RPM does not result in increased blood flow (LPM).
    2. The circuit begins to “Chatter.”
    3. SvO2 > 70%

IF flow is too low: 1. Infuse more volume 2. reposition venous cannula 3. add a venous cannula

2. Arterial Blood Gas Analysis:

  • GOAL:  “normal” ABG (PaO2 80-100; PaCO2 35-45)

IF PaO2 < 80,   THEN you need more blood flow through the Oxygenator

IF PaO2 > 100, THEN its time to add a gas blender and turn down the FiO2 from the Oxygen source

IF PaCO2 < 35, THEN decrease your “Sweep Gas Rate” by lowering the LPM on the O2 supply

IF PaCO2 > 45, THEN increase your “Sweep Gas Rate” by increasing the LPM on the O2 supply


3. Optimize Systemic Vascular Resistance (SVR)

SVR = (MAP – CVP) x 80

SVR = (MAP – 0)      x 80
Blood Flow

***GOAL = SVR > 800

IF, for a given blood flow, the MAP is unreasonably low, you need a pure VASOPRESSOR = Phenylephrine

IF, for a given blood flow, the MAP is unreasonably HIGH, you need a VASODILATOR = Nitroprusside

Or, Goal MAP > 65


 The Shinar 3000: Tall Paul ECMO Simulator

Zack built an ECMO simulator model in his garage. Here is the video:

Tall Paul Compilation 3 from Joe Bellezzo on Vimeo.

Keep up with the EDECMO Project

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  1. Gary Grist RN CCP, retired says

    Thank you for sponsoring this web site.
    This discussion is a good vest pocket summary of how to quickly put a patient on ECMO/ECPR. However there are certain refinements that have been overlooked in your discussion; the most important being whether this is an ECMO patient or an ECPR patient. The distinction is critical because ECPR patients are in great danger from reperfusion injury whereas ECMO patients are at much less risk from reperfusion injury. ECPR patients are those who are undergoing CPR or who are in severe shock. Because of this their physiology has changed to such a degree that their protective enzymes (antioxidants) are non-functional. Restoring oxygenation and perfusion suddenly, as with a pump, will re-oxygenate the tissues before their intracellular pH has been corrected and the antioxidants re-activated. The most common symptom of this reperfusion injury will be a stroke; either an infarct or hemorrhage.
    Your emphasis in restoring the ABG to normal is incomplete without a VBG to compare it to. For example, here are real ABG and VBG from a patient just placed on ECPR; ABG: 7.31 / 48 / 375 (pH / pCO2 / pO2), VBG: 6.90 / 106 / 26 (pH / pCO2 / pO2). As you can see the ABG is close to normal but the VBG is extremely hypercapnic. This indicates that an extreme amount of CO2 is trapped intracellularly and that the intracellular enzymes are deactivated. So they cannot provide protection against reperfusion injury. In this situation several things should be done. 1) Reduce the paO2, 2) immediately cool the patient to at least 32C (these two items will help to protect against reperfusion injury from oxygen stress), 3) give a dose of dantrolene to protect against reperfusion from calcium stress. Once the venous CO2 has been normalized and the gradient has been narrowed there is much less risk of reperfusion injury and oxygenation can be increased with sweep gas FiO2 or blood transfusion if needed.
    You also mention that you have small arterial and venous lines in patients prior to cannulation. I assume these are to aid in directing resuscitation efforts. If a SVC or RA venous line is in place, a VBG sample should ALWAYS be drawn along with an ABG. Here are some samples from a resuscitation patient in the early stages of myocarditis and cardiogenic shock; ABG: 7.38 / 24 / 127/-9.4 (pH / pCO2 / pO2/BE), VBG: 7.19 / 51 / 34 / -9.3 . The CO2 gradient between the ABG and VBG indicates a critical physiology. If resuscitation efforts do not narrow this gradient, ECMO or ECPR should be implemented. Physicians delayed the implementation of ECMO in this patient, instead opting to resuscitate in the conventional manner with resuscitation maximized to include, among other things, epi: 1 mcg/kg/min, norepi: 0.2 mcg/kg/min, vasopressin; 4 mu/kg/min and 13 liters of crystalloid in this 11 year old patient. The patient died without ever being placed on pump.
    I am now a retired perfusionist, but I wrote an article addressing the subject of differentiating ECMO and ECPR patients. This may provide additional information to those interested: Grist G. Extracorporeal membrane oxygenation (ECMO) or extracorporeal cardiopulmonary resuscitation (ECPR): A critical life or death choice. Progress in Pediatric Cardiology; 2008 January; 24(2):113-116

  2. Thanks for the post. I cannot see the attachments for the flipped classroom though. Is it me or are they missing?

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