Console checklist
Major Components
- Maquet Rotaflow Console
- Remote Pump Drive (with cable)
- Emergency Hand Crank
- Heater
- Blender and Rotameter
- Surge protector/ power adaptor
- Isolation transformer (underneath lowest shelf)
- Oxygenator Holder
- Transducer Holder
- Gas Flow tubing (with silicone end)
Drawer Contents
- Cable ties
- Green Oxygen (gas) tubing (5 M)
- Securing dressing (Grip-locks) with velcro locks
- Metal Heater tubing connecting bridge
On Hooks
- ECMO clamps (x4)
- Pressure Bag
Daily check required and post patient use prior to storage.
Top of Trolley
ECMO Console
- Ensure the power cord plugged in and the powerpoint LED light is illuminated.
- Ensure A/C indicator light lit up on the front of the console
- Ensure pump head driveline attached to rear of drive console (Rotaflow II)
Trolley Draw – ensure all present
- Metal Heater tubing connecting bridge
- Cable tie gun
- Spare black cable tie’s x 10
- Spare cannulae securing device x 2 (griplock)
- 5 metres of green spare oxygen tubing
Front of trolley – ensure present and attached
- Fresh gas flow meter
- Gas to oxygenator delivery tubing
- Gas blender
- Maquet water heater & Tubing
Rear of Trolley – ensure present and attached
- Emergency hand crank
- Oxygenator holder and arm
- Maquet Pump head and arm with attached driveline from Drive console
- Ensure flow sensor latch present and closed
- Ensure IV pole present
Sides of trolley
- Four circuit clamps
- Pressure bag
ECMO console positioning
ECMO console is situated at the foot of the bed with the pump head and oxygenator facing toward the patient. The gas and blood flow control face away from the patient. Power cords and gas tubing must be not tangled with the ECMO circuit and must not protrude onto the floor space around the patient bed. Torsion on the ECMO circuit is to be avoided.
The pump head needs to face up (Rotaflow II). Position the pump head horizontally at a level above the oxygenator. In the case of air embolism, this will trap air first in the pump, potentially stall it before overwhelming the oxygenator and returning air to the patient.
Note: dual lumen jugular catheter configuration for VV ECMO the standard circuit tubing length will be insufficient to reach an ECMO trolley situated at the foot of the bed. In this case, the trolley is positioned at the patient’s left or right side. It will be re-positioned to the top of the bed for intrahospital transport. For femoro-jugular configurations the preference would be to add additional tubing for the jugular limb and the console to remain at the foot end.
Oxygen connections
After initiation of the patient on ECMO or upon return to the cubicle the oxygen supply has to be transferred from the portable oxygen to “wall” oxygen and the blender alarm is tested during connection (audible alarm). The fresh gas flow meter should be set to the desired gas flow. The reading should be made from the centre of the “ball” on the flow meter.
The outlet tubing from the fresh gas flow meter is briefly occluded as the “ball” in the flow meter is observed. Shifting of the “ball” in the flow meter in response to the occlusion indicates a functioning fresh gas flow meter.
Fresh gas tubing is connected to the oxygenator inlet. Ensure only one flow meter is on either the high (up to 10 L/min) or low flow (up to 1 L/min) meter of and not both (unless you deliver 11L/min).
Transmembrane Pressure Monitoring (Rotaflow II only)
Once ECMO support is established, pre- and post-oxygenator pressure monitoring can be established.
- Connect a pre-primed and pressurised transducer and bag to the extensions on the pre- and post-oxygenator port. Aspirate via the 3-way tap and then open the tap to the circuit.
- Ensure the bag is pressurised to 300mmHg and hung below the drive console and away from the external drive unit
- Connect transducers to pressure modules, select appropriate monitor labels and zero.
- Record the transmembrane pressure gradient two hourly (the difference between the pre- and post-oxygenator pressures)
- A normal gradient should be between 20 to 40mmHg. Higher readings may be related to clot formation within the oxygenator or excessive flow rates. For more details see haemolysis.
The pressurised fluid bag for transducing the pre and post oxygenator pressure in the PLS circuit must be located below the level of the ECMO drive console and not above the external drive unit. This will ensure that no fluid spills into the console or the external drive unit in the event of fluid bag rupture.
Cardiohelp utilises internal pressure monitoring characteristics and does not require external pressure monitoring (see HLS priming and HLS zeroing).
ECMO Console settings
Alarm Settings
ECMO blood flow alarm is set 0.5 L/min below target flow
Speed setting
The pump speed RPM is selected to deliver the desired circuit blood flow. The pump speed setting required to achieve a given circuit blood flow is dependent on the resistance to flow in the circuit and the load across the circuit.
Caution LPM Function
LPM stands for ‘liters per minute’. Both the Rotaflow II (“LPM Mode”) and Cardiohelp consoles offer the LPM function which, when set, will adjust the pump speed automatically to achieve a selected blood flow target. This function should never be used at The Alfred.
Mode setting
Cardiohelp System defaults to “therapy” mode on startup. Two modes for use at the bedside are ‘VV’ or ‘VA’ modes. This needs to be changed in the menu option and then the relevant mode selected. Other options are available: e.g. PALP or VAD but not used at present. Changing the mode will not affect the running of the pump, but will alter the display and monitored variables. Only the ‘VV’ or ‘VA’ modes are to be used at the Alfred ICU.
Interventions setting
The Cardiohelp system has the added functionality of setting “Interventions” around certain clinical parameters such as circuit pressures and blood flow. When “Interventions” are enabled, the device automatically controls interventions in response to bubble, circuit blood flow, or pressure alarms. WE DO NOT SUPPORT THE USE OF INTERVENTIONAL SETTINGS WITH THE CARDIOHELP ECMO DEVICE IN THE ALFRED ICU due to the risk of unintentional alterations to (including discontinuation of) ECMO support.
Heater unit management
Heater unit set up
It is essential to warm the heater before connection to an oxygenator on a running circuit that is connected to a patient (otherwise the patient is cooled).
- Ensure that the heater water level is approximately 75-80% full. This is indicated via the water level on the front of the heater. If low, escalate to the ECLS CNC. The heater protocol enables change of water and/or top-up of water. This should be carried out in the respiratory room and away from the clinical cubicle.
- Ensure to connect the bridging device between the heater hose ends to aid recirculation (see picture below). Also, make sure to reattach it when disconnecting a patient to make sure it is not lost.
The brass coloured connection to the ECMO console here shown with the bridging device, comes in a straight and angled version which is better suited for the use with the HLS circuit.
- Turn on unit and recirculate water until desired temperature attained (usually 37°C), this will only take a few minutes
- Turn off the heater unit prior to attaching hoses to an oxygenator (pull the gold rings in a downward motion and reattach to the connectors on either side of the oxygenator (same connections for HLS or PLS oxygenator).
- Turn on the heater unit once hoses are attached to the oxygenator, monitor patient temperature and set the heater accordingly.
Further related links
Blender settings
The optimal oxygen target, and the role of the blending in VA ECMO patients, was recently evaluated in a multicentre RCT [1]. The trial compared a lower right radial and post oxygenator oxygenation target (92–96%), achieved by reducing both ventilator FiO₂ and blender FGF O₂ below 1.0, to a higher target (97–100%).
The lower-target strategy showed no clinical benefit across a range of outcomes, and was associated with a higher risk of hypoxic episodes. Based on these findings – pending further evidence – we maintain the blender FiO₂ at 1.0 for all VA ECMO cases, including during weaning. For VV ECMO, the blender FiO₂ should also remain at 1.0 at all times.
[1] Burrell, A. et al. Conservative or liberal oxygen targets in patients on venoarterial extracorporeal membrane oxygenation. Intensive Care Med 50, 1470–1483 (2024). [PMID39412548]
The fresh gas flow is set here to 3.75 L/min (the flow is read in the middle of the ‘ball’). with a FiO2 of 1.0.