How to choose an anaesthesia workstation: 7 criteria

An anaesthesia workstation brings together on a single trolley a ventilator, one or more vaporisers, a patient circuit and gas monitoring. It is used every day, in every room, and the choice commits the operating theatre for the long term. Here are seven criteria to examine, illustrated with values taken from the manufacturer's brochures for the devices we distribute.

1. Ventilation modes

The built-in ventilator determines which patients the workstation can manage. Volume-controlled and pressure-controlled modes form the foundation; volume-guaranteed modes, such as PCV-VG or SIMV-VG, broaden the scope of use, particularly in paediatrics and in patients whose lung compliance changes during surgery. A pressure support mode is useful during emergence, when the patient resumes spontaneous breathing.

Beyond the list of modes, look at the associated setting ranges. The brochure for the WATO EX-65 states an I:E ratio of “50:1 to 1:50” and a PEEP of “OFF, 3 to 30 cmH2O”. It is these ranges, set against the department's protocols, that show whether a mode is genuinely usable.

2. Tidal volume and flow ranges

Volume and flow ranges indicate the variety of patients the device can ventilate, from the newborn to the heavily built adult. A distinction must be made between what the device can set and what it can measure: the two do not necessarily cover the same range, and a brochure does not always present both.

• Monitored tidal volume: “0 to 3 000 mL” according to the WATO EX-65 brochure.
• Minute volume: “0 to 100 L/min”.
• Airway pressure: “-20 to 120 cmH2O”.
• Maximum gas flow: “120 L/min + fresh gas flow”.

In specifications, these ranges are written as minimums derived from the department's patient population, not as a copy of one model's values.

3. Integrated monitoring and gas analysis

The anaesthesiologist monitors the patient, the ventilation and the gases at the same time. The expected minimum includes pressure and flow waveforms, measured volumes and the associated alarms. Breath-by-breath gas analysis completes this foundation:

• Inspired oxygen fraction: the WATO EX-65 brochure states an FiO2 of “18 to 100 %”.
• Measurement of EtO2, CO2 and N2O.
• Automatic identification of halogenated agents.
• Depending on the model, depth of anaesthesia (BIS) or neuromuscular transmission monitoring (NMT), offered for example on the A7.

4. Agent and vaporiser management

Vaporisers deliver the halogenated agent at the selected concentration. Check which agents they accept, how many mounting positions the workstation offers, and whether their filling system matches the bottles already used in the facility. A vaporiser poorly suited to the theatre's habits quickly becomes a source of errors or extra cost.

Low fresh gas flow is the second lever. It reduces anaesthetic agent consumption, and therefore operating costs, provided the workstation doses and measures the delivered mixture precisely. Several models in the range offer help with this setting: the WATO EX-65 PRO and the A7 highlight a flow optimiser, and the A7 a digital gas mixer. It is better to understand what these functions actually do than to stop at their trade name.

5. Ergonomics, footprint and autonomy

The workstation stays in place throughout the procedure, as close as possible to the patient's head. Its footprint must be compatible with the room's floor space, the ceiling pendants and the movement of the team. Screen readability, the work surface, the drawers, the brake and cable routing matter day to day as much as ventilator performance. As a reference point, here is the footprint stated in the WATO EX-65 brochure:

• Height: “1 370 mm”.
• Width: “945 mm (including breathing system)”.
• Depth: “690 mm”.
• Weight: “< 145 kg (without vaporiser or cylinder)”.

Autonomy completes the picture. Check the required power supply — “220-240 V, 50/60 Hz, 6 A” for the WATO EX-65 — and the presence of a backup battery, whose duration should appear on the datasheet.

6. Integration into the theatre and the network

An anaesthesia workstation does not operate in isolation. It connects to the room's medical gas outlets, where applicable to backup cylinders, and increasingly to the hospital information system. On this last point, the brochure for the A5 indicates data transfer via the HL7 protocol, in line with the IHE profile for the patient care domain (PCD).

On the gas side, check that the drive gas pressure accepted by the workstation matches that of the facility's network: the WATO EX-65 brochure states “From 280 kPa to 600 kPa”. For a project covering the whole room — lighting, table, ceiling pendants, monitoring — the approach is described on our operating theatre page.

7. Maintenance and documentation

An anaesthesia workstation is checked before each use and undergoes regular preventive maintenance. Its design has a direct effect on the biomedical department's workload and on room availability. The A7 brochure describes a self-test procedure displayed with graphs and tables; the WATO EX-65 PRO brochure highlights longer-life flow sensors that make servicing easier. Also require complete documentation:

• The user manual and the service manual, preferably in French.
• The list of wear parts and consumables, with their references.
• The preventive maintenance interval recommended by the manufacturer.
• The conditions for intervention in the event of a breakdown and the availability of spare parts.

These conditions are set at the time of purchase, not after delivery. Our organisation is presented on the after-sales service page, and the datasheets for each model can be downloaded from its product page.

Comparing offers on the evidence

None of these criteria is sufficient on its own. A workstation suited to a paediatric surgery theatre is not necessarily the right choice for a general surgery room, and a uniform fleet often matters as much as the performance of a single model. Start from the department's practices, turn them into measurable requirements, then compare them with the brochures. To receive a priced proposal for one or more models in the Mindray range, submit a quote request stating the number of rooms to equip and the agents used.