Maquet Servo-U Troubleshooting

Obstruction leading to constant high airway pressure (>PEEP +15 cmH2O) during: > 2 breaths or 5 seconds, whichever is greater; 15 ±1.5 s if less than 2 breaths are triggered).

Possible Causes

• Airway pressure exceeds the preset upper-pressure limit
• Kinked or blocked tubing
• Mucus or secretion plug in the endotracheal tube or airways
• Patient coughing or fighting ventilator
• Inspiratory flow rate too high
• Improper alarm setting
• Blocked expiratory filter

The patient circuit is the plastic tubing that connects the patient to the ventilator and delivers gas to and from the patient. Check to make sure there are no kinks in the hose or that there are no obstructions within the tubing.

Check the ventilator settings to ensure that the airway pressure is set to the intended value and that the high-pressure alarm is not due to a change in settings.

Check the ventilator alarm settings to ensure that the limits for which the alarm activates are not within the operating pressure of the ventilator.

Battery voltage too low. Cannot guarantee continued ventilator system operation.

Plug the ventilator into the mains power of the building to restore power to the onboard batteries.

If this alarm message arises you must replace the batteries.

Battery Replacement Guide

Less than 10 minutes left of battery operating time.

Plug the ventilator into the mains power of the building to restore power to the onboard batteries.

If this alarm message arises you must replace the batteries.

Battery Replacement Guide

Measured O2 concentration is below the set value by more than 5 vol.% or concentration is below 18 vol.% which is independent of settings; gas delivered in the O2 supply line is not O2; O2 sensor faulty or exhausted; O2 cell uncalibrated; gas module for O2 faulty.

If this alarm message arises you must replace the O2 supply.

O2 Supply Replacement Guide

To adjust the O2 cell:

• Tap CALIBRATION & TESTS in the extended menu
• Tap O2 CELL ADJUSTMENT once, then again
• Tap Yes to perform the O2 cell adjustment
• Tap OK

The pre-use check includes tests and measurements of:

• internal technical functionality
• barometric pressure
• gas supply
• internal leakage
• pressure transducers
• safety valve
• O2 cell/O2 sensor
• flow transducers
• battery switch
• patient circuit leakage, compliance, and resistance
• alarm state
• alarm output connection (option)

Leakage too high. The mask/prongs may not be adjusted properly for the patient or maybe the wrong size.

The patient circuit is the plastic tubing that connects the patient to the ventilator and delivers gas to and from the patient. Check to make sure there are cracks or holes in the tubing, and that the tubing is securely sealed to the ventilator and mask.

The endotracheal tube is a thin plastic tube that is placed inside the mouth of the patient to deliver oxygen. Check the tubing to ensure that there are no obstructions, cracks, or leaks.

Check the patient interface (breathing mask) to ensure that it forms an airtight seal around the patient’s mouth and that it is delivering oxygen to the patient.

Technical problem with the expiratory cassette.

If this alarm message arises you must replace the expiratory cassette.

Expiratory Cassette Replacement Guide

The pre-use check includes tests and measurements of:

• internal technical functionality
• barometric pressure
• gas supply
• internal leakage
• pressure transducers
• safety valve
• O2 cell/O2 sensor
• flow transducers
• battery switch
• patient circuit leakage, compliance, and resistance
• alarm state
• alarm output connection (option)