Equipment Used

Overview

This protocol is written for the use with the Maquet ECMO Systems

• PLS 2050 circuit and Rotaflow® Blood Pump
• HLS Advanced 7.0 circuit and Cardiohelp®

The listed equipment reflects key parts of the equipment used. For a more detailed current ECMO equipment overview refer to the ECMO Equipment Stock List.

Principles of equipment maintenance and management

• All ECMO machine components are to be serviced and maintained by Maquet service engineers as per service contract (see ICU Equipment Nurse)
• Do not send ECMO machines to biomedical engineering (consult ECLS Coordinator if unsure)
• All ECMO machines are cleaned in respiratory store after patient use
• The water heater solution is changed at every patient use (or clinical hours) as per separate guideline
• All ECMO machines must be plugged into power during storage
• ECLS Coordinators and ICU Equipment nurse will ensure that ECMO stock is adequate
• ECLS Coordinators will ensure a pre primed PLS circuit is ready to use at all times
• Do not expose any part of ECMO circuit or machine to alcohol
• Do not dispose any metal ECMO clamps
• Do not allow fluid to come into contact with ECMO consoles or drive units

ECMO console

Rotaflow

This section provides an overview of the key features of the rotaflow device further information can be found in the user manual and under Rotaflow alarms.

The entire PLS system consists of the Rotaflow console, Rotaflow drive unit with holder, Emergency drive and an additional holder for the oxygenator as part of the PLS disposable circuit.

The Rotaflow device was initially used for applications in cardiothoracic surgery but with an extended ICU kit can be used as an ECMO pump. Several features are only applicable when used for cardiopulmonary bypass not in ECMO. The mode that it is used in for ECMO hence is called ‘FREE’ (independent from a cardiopulmonary bypass monitoring and without interventions).

The drive unit is separate from the oxygenator which allows its use for temporary circulatory assist (without an oxygenator) such as temporary RVAD, LVAD or BiVAD. This is not possible with the Cardiohelp (see below).

Advantages

• Simple to operate, simple display
• Can be used for temporary RVAD or LVAD
• Easy to assess both surfaces of the oxygenator and the pump head
• PLS circuit substantially cheaper than HLS

Disadvantage

• Heavy ~15kg, multiple components – challenging for transport
• Pressure measurements not integrated into console
• No access pressure reading
• Low battery life

Image PLS

Cardiohelp

This section provides an overview of the key features of the cardiohelp unit.

Further information

• Instruction guidelines Getinge – user manual with operational explanations
• Service manual Getinge – for technical details
• Set up, initiating ECMO

The cardiohelp is a compact ECMO unit that is run with the HLS circuit.

Advantages

• Informative display, including Hb and venous SpO2
• Give access pressure reading
• Compact with protection arm, ready for transport

Disadvantage

• Inability to assess pump head
• Virtually no visibility of inflow oxygenator surface
• HLS circuit substantially more expensive than PLS circuit

Note: Data on the ECMO run can be recorded. The recording however has to be started prospectively (see image below) and can then later be downloaded to an USB.

Heater

The principles are outlined here for more practical information see daily care and heater alarms.

This is a water based heater with the heat exchanger being incorporated in the oxygenators used with the Rotaflow and Cardiohelp system. The water temperature is set to the desired level and will approximate the body temperature achieved depending on heat loss and the blood flow through the circuit.

Key features

• Water tank needs to filled before the start
• The filling volume between minimum and maximum level is 0.7 litres
• Set up allows maximum of 1 m difference in height between the unit and the oxygenator
• The temperature can be set between 33°C and 39°C, temperatures of 38°C and above require confirmation
• Water temperatures of 40°C lead to an independent shut down as a safety precaution
• The heater provides heating only – there is no active cooling function

For further information about the Heater Unit HU 35

• Heater user manual
• Heater technical information

Blender

The blender has an inlet from wall air in addition to oxygen. The connections need to be firm otherwise a loud, very characteristic high-pitch noise will alert to this.

The blender has three main functions

• Ability to titrate fresh gas flow with a finer scale below one liter per minute. This is important in weaning stages of VV ECMO applications
• The oxygen concentration can be titrated with a blend of oxygen and air from 21% to 100% oxygen
• The connection to the wall allows avoids ‘running out’ of cylinder oxygen but does rely on the hospital alarm system and is crucial to remember that it needs to switched to

From the left: CO₂ is not connected; fine O₂ titration up to one litre/min; main fresh gas flow up to 10 litre/min. The blender on the right, labelled ‘AIR-OXYGEN MIXER’ can be set between room air and 100% oxygen.

Cannulae

Multi-stage cannulae

Standard access in VA and VV ECMO

Single stage cannulae

Comprise venous and arterial return cannulae as well as short ‘arterial’ cannulae used for venous access in the jugular position.

Dual lumen cannulae

Dual lumen or double lumen cannulae are single cannulae partitioned into two lumens with both access blood flow and return blood flow, similar to vascular access catheters used in renal replacement therapy.

The cannula in use at present is 31 Fr Avalon ELITEⓇ Bi-Caval Dual Lumen Catheter, with an insertion length of 31 cm and the return port 7.5 cm from the tip. For details see procedure section dual lumen cannula.

Distal perfusion cannula

The distal perfusion cannulae in use are wire reinforced, sizes are 6 Fr and 8 Fr. The reinforcement allows a fairly steep angle of insertion without kinking. The function of the blood flow through the cannula is determined by the pressure in the return cannula and the peripheral vascular resistance in the lower limb.

The distal perfusion cannula pack includes

• Instructions
• Reinforced cannulae (see image below)
• Extension (see image below)
• Tracheostomy foam
• Silk 2-0 suture

Details about insertion and use can be found here.

Cannula Arrow 6Fr (green top) and 8Fr (blue top)

Distal perfusion cannula extension

These 3mm tubing extension with ‘male’ luer lock connection are used, minimising the length of the distal perfusion circuit.

The shown male-male luer lock extension comes in 9 and 14cm length.

ECMO pack

A customised ECMO pack contains all essentials for cannulation apart from liquids, ECMO clamps and a cannulation set (needle, dilator, cannulae).

• Bowl 1.5 L blue
• Gallipot 150 ml
• Bone bowl 600ml green
• 2x Kidney dish 700 ml clear
• 15x non-woven swabs 10 cm x 10 cm
• Angio drape with bendable tabs
• 2x syringe 10ml luer lock
• 4x syringe 60ml catheter tip
• 3x absorbent foam applicator 15cm blue
• Scissor sharp/blunt 13cm