Medtronic Capnostream 20p

Asset Type

Capnography Monitor

Manufacturer

Medtronic

Model

Capnostream 20p

What This Guide Helps With

This guide helps troubleshoot the EtCO2 LOW ALARM on a Medtronic Capnostream 20p capnography monitor. This alarm indicates that the measured end-tidal CO2 value is below the lower alarm limit. It may reflect a real patient condition, poor ventilation, airway or circuit problems, low perfusion, apnea risk, or a false low reading caused by sampling line, cannula, airway adapter, or connection issues.

Step-by-Step Troubleshooting

Ensure Patient Safety First

• Immediately assess the patient or confirm clinical staff are actively assessing the patient.
• Treat this as a patient safety alarm first, not an equipment problem.
• Do not silence, ignore, or troubleshoot the alarm as a device issue until the patient condition has been evaluated.
• If the monitor, sampling line, or EtCO2 value is suspected to be unreliable, move the patient to a backup monitoring method before removing the device from use.

Verify the Reported Alarm and Behavior

• Confirm the monitor is displaying EtCO2 LOW ALARM.
• Observe the EtCO2 value, capnogram waveform, respiration rate, and alarm timing.
• Determine whether the alarm occurs continuously, intermittently, after patient movement, during transport, or after a sampling line or accessory change.
• Check whether other alarms are present, such as no breath detection, filter line blockage, low respiration rate, or waveform loss.

Confirm Whether the Reading Matches the Patient Condition

• Ask clinical staff whether the low EtCO2 value matches the patient’s current condition, airway status, ventilation status, and treatment plan.
• Confirm whether the patient is breathing adequately and whether airway or respiratory support equipment is connected correctly.
• Look for signs that the alarm may be caused by a true clinical issue rather than an equipment issue.

Check the Lower EtCO2 Alarm Limit

• Review the configured lower EtCO2 alarm limit.
• Compare the setting with the patient condition, clinical expectation, and care area protocol.
• If the alarm limit appears inappropriate, have clinical staff adjust it according to policy.
• Do not change clinical alarm limits unless authorized by facility procedure.

Inspect the CO2 Sampling Line or Airway Adapter

• Check the Microstream CO2 sampling line, cannula, or airway adapter for disconnection, loose fit, kinks, crushing, contamination, moisture, or secretions.
• Confirm the sample line is compatible with the monitor and properly connected.
• Replace the sampling line if it is damaged, blocked, wet, contaminated, or questionable.
• Confirm the alarm clears and the EtCO2 value and waveform stabilize after correcting the sample path.

Confirm Proper Patient Interface Placement

• For nasal or oral sampling, confirm the cannula is positioned correctly and has not shifted away from the nose or mouth.
• For intubated or ventilated patients, confirm the airway adapter is installed correctly and the breathing circuit is connected.
• Check whether patient movement, transport, or repositioning caused the sample line to move out of position.

Check for Leaks or Disconnections in the Breathing Circuit

• If the patient is ventilated, inspect the breathing circuit, airway adapter, ET tube or trach connection, filter, and sample line connection points.
• Ask respiratory therapy or clinical staff to verify the circuit if a leak, loose fitting, or disconnection is suspected.
• Correct any external circuit or connection issue before suspecting monitor failure.

Evaluate the CO2 Waveform

• Review the capnogram waveform instead of relying only on the numeric EtCO2 value.
• A weak, flat, irregular, or absent waveform may indicate poor sampling, apnea, shallow breathing, obstruction, disconnection, or a true clinical condition.
• If the waveform improves after repositioning or replacing the sample line, the issue was likely external to the monitor.

Swap Known-Good Accessories

• If the patient is stable and clinical staff suspect a false alarm, replace the CO2 sampling line, cannula, or airway adapter with known-good compatible accessories.
• Recheck the EtCO2 value, waveform, respiration rate, and alarm status.
• If the alarm clears after accessory replacement, document the failed or questionable accessory as the cause.

Check the Monitor Connection

• Confirm the CO2 sampling line is fully seated at the monitor connection.
• Inspect the inlet area for visible damage, contamination, cracked fittings, or loose connection points.
• Do not insert tools, perform internal cleaning, or disassemble the monitor during clinical troubleshooting.

Test the Monitor Away From the Patient

• After alternate monitoring is established, remove the monitor from patient use if the device is suspected to be unreliable.
• Use a known-good compatible CO2 sampling line and approved facility test method to verify monitor response.
• Confirm whether the monitor detects sample changes normally or continues to show low EtCO2 behavior under test conditions.

If the Problem Persists

If the EtCO2 LOW ALARM continues after the patient has been assessed, alarm limits are verified, the sampling line and accessories are replaced, connections are checked, and the issue remains during bench evaluation, external causes have been ruled out.

Persistent false low EtCO2 readings may indicate a device sampling, sensor, pneumatic, calibration, or internal measurement problem.

The device should be removed from service, labeled Out of Service, and sent for repair or bench evaluation.

Clinical Use Tip

Never troubleshoot a low EtCO2 alarm as an equipment issue while the patient is actively relying on the monitor. Move the patient to a backup device or alternate monitoring method first, then troubleshoot the Capnostream 20p only after patient monitoring remains safe.

Work Order Documentation (CCR Method)

CCR = Complaint, Cause, Resolution

Complaint

What was reported by the clinical staff.

Example:
"Capnostream 20p displayed EtCO2 LOW ALARM during patient monitoring. Staff reported EtCO2 value below the lower alarm limit with concern for low or inaccurate CO2 reading."

Cause

What was observed during troubleshooting.

Example:
"Patient was assessed by clinical staff. Lower EtCO2 alarm limit, CO2 sampling line, patient interface placement, airway/circuit connections, and monitor inlet connection were checked. Issue was caused by a displaced/kinked CO2 sample line, which prevented accurate exhaled CO2 sampling."

Resolution

What action was taken.

Example:
"Replaced/repositioned CO2 sampling line and confirmed stable EtCO2 numeric value, visible waveform, and no recurring EtCO2 LOW ALARM. Device returned to service."

Helpful Details to Include (If Known)

• Alarm behavior
• Accessories swapped
• Power behavior
• Environmental factors
• Indicator lights
• Final device status

Final Thought

The EtCO2 LOW ALARM must be treated as a patient safety alarm first and an equipment issue second. Clinical Engineering should verify the alarm, rule out simple external causes, confirm accessory and sampling integrity, and escalate when the monitor cannot be trusted. Clear CCR documentation protects the patient, the technician, and the device history.

That is successful troubleshooting.