Drager Evita V500

Asset Type

Ventilator

Manufacturer

Drager

Model

Evita V500

What This Guide Helps With

This guide addresses situations where the Drager Evita V500 ventilator displays:

• Inspiratory or expiratory flow sensor warnings or failures
• Abnormal tidal volumes or flow readings
• Failed pre-use checks related to flow sensors
• Alarm messages indicating sensor contamination or calibration errors

The guide focuses on logical, external troubleshooting first, minimizing unnecessary disassembly and prioritizing patient safety.

Step-by-Step Troubleshooting

Verify Power and Connections

• Ensure the ventilator is plugged into a stable power source.
• Check that all cables and connectors for flow sensors and the patient circuit are securely attached.

Reason: Loose or intermittent connections can mimic sensor failure.

Inspect Patient Circuit

• Remove and examine the inspiratory and expiratory tubing for visible moisture, condensation, or obstruction.
• Ensure that filters, humidifiers, and condensate traps are properly seated and not blocked.

Reason: Contaminated or obstructed circuits can trigger false flow sensor alarms.

Check Sensor Orientation and Installation

• Ensure the flow sensor is installed in the correct orientation as per labeling (inspiratory vs expiratory).
• Confirm the sensor is fully seated and locked in place.

Reason: Misalignment can cause inaccurate readings or contamination warnings.

Clean or Replace Disposable Flow Sensors

• If using disposable or single-patient sensors, replace with a new unit.
• If reusable, follow manufacturer-approved cleaning and drying procedures.

Reason: Contamination buildup affects sensor accuracy.

Run Sensor Calibration/Auto-Zero Procedure

• Navigate to the ventilator’s service or pre-use check menu and perform flow sensor calibration.
• Observe whether calibration completes successfully or produces error messages.

Reason: Ensures sensor electronics are reading correctly after cleaning or replacement.

Observe for Alarms or Unusual Behavior

• Monitor tidal volume, inspiratory, and expiratory flow readings during a self-test or with a test lung.
• Listen for abnormal airflow sounds or pressure fluctuations.

Reason: Confirms functional correction before returning device to patient use.

If the Problem Persists

External causes have likely been ruled out. The flow sensor or internal measurement module may be defective.

• Remove the ventilator from service.
• Label as Out of Service.
• Send for bench evaluation or manufacturer repair.

Note: Knowing when to escalate is proper troubleshooting and ensures patient safety.

Clinical Use Tip

• Do not troubleshoot on a patient: Move the patient to an alternate ventilator first.
• Only handle the flow sensor when the circuit is disconnected and safe.
• Always confirm the ventilator is functioning correctly with a test lung before returning to clinical use.

Work Order Documentation (CCR Method)

CCR = Complaint, Cause, Resolution

Complaint

What was reported by the clinical staff.

Example:
“Ventilator displayed expiratory flow sensor failure during pre-use check; tidal volumes appear inaccurate.”

Cause

What was observed during troubleshooting.

Example:
“Inspection revealed moisture accumulation in the expiratory flow sensor and tubing; calibration failed before cleaning.”

Resolution

What action was taken.

Example:
“Flow sensor and circuit replaced per protocol, sensor cleaned/replaced, calibration successfully completed, ventilator returned to service with no alarms.”

Helpful Details to Include

• Verify outlet/gas supply stability
• Check if patient circuit contains condensation or water
• Document alarm behavior and frequency
• Note sensor serial number and type
• Record final ventilator status after troubleshooting

Final Thought

Patient safety is paramount. Start with simple, external checks and escalate only when necessary. Accurate documentation ensures future reference and supports proper device management.

That is successful troubleshooting.