CDRH is issuing this Early Alert to notify the public of a potentially high-risk device issue. The FDA will keep the public informed and update this web page as significant new information becomes available.
Affected Product
The FDA is aware that Hamilton Medical has issued a letter to affected customers recommending certain coaxial breathing circuit sets used with HAMILTON-C1, HAMILTON T-1, and HAMILTON-MR1 ventilators have updated use instructions.
Affected devices:
|
Product Name |
Brand Name |
Product Number |
UDI-DI |
|---|---|---|---|
|
T1 CIRCUIT 240 +VALVE B/10 |
Hamilton Breathing circuit sets, coaxial |
260127 |
|
|
T1 CIRCUIT 180 +VALVE B/20 |
Hamilton Breathing circuit sets, coaxial |
260128 |
|
|
MR1 CIRCUIT 300 +VALVE B/10 |
Hamilton Breathing circuit sets, coaxial |
260167 |
|
|
MR1 CIRCUIT 480 +VALVE B/8 |
Hamilton Breathing circuit sets, coaxial |
260168 |
What to Do
Users should review and follow the pre-operative test instructions and troubleshooting instructions prior to continued use.
On May 18, 2026, Hamilton Medical sent all affected customers a letter recommending the following actions:
- Verify unimpeded expiratory gas flow prior to use by ventilating a test lung using the settings provided by Hamilton Medical after performing the pre-operative test.
- If no “exhalation obstruction” alarm is issued, the expiratory valve is safe to use.
- If the “exhalation obstruction” alarm is triggered, do not use the coaxial breathing circuit set. The coaxial breathing circuit set must be discarded and replaced.
- If the “Exhalation Obstructed” alarm is triggered on the ventilator, users should perform the following steps:
- Disconnect the patient from the ventilator and ensure alternative means of ventilation (e.g. alternative ventilator, hand bagging, etc.).
- Once patient safety is ensured, remove the expiratory valve set and overcome the membrane adhesion by detaching the membrane from the expiratory valve body once.
- Place the membrane back onto the body. Then, ensure the membrane is aligned with the expiratory valve body with the metal facing up (do not press onto the metal) and install the expiratory valve set into the exhaust port on the ventilator.
- Alternatively, use a new expiratory valve set.
- Inform all potential users of affected coaxial breathing circuit sets about this issue and post the provided notice in your facility. Make sure recommended actions are followed.
- Affected products may continue to be used with the risk mitigations provided above.
Check this web page for updates. The FDA is currently reviewing information about this potentially high-risk device issue and will keep the public informed as significant new information becomes available.
Reason for Alert
Hamilton Medical stated that certain lots of coaxial breathing circuit sets preassembled with an expiratory valve set do not perform as intended. In some cases, the expiratory valve membrane adhered to the sealing ring on the body of the expiratory valve, impairing valve opening and expiratory gas flow. The issue is not detected during the pre-operative test of the ventilator unless a test lung is actively ventilated. If the expiratory valve membrane is adhered to the sealing ring, the malfunction appears within the first breaths after ventilation is initiated.
When the expiratory gas flow is impeded, the end-expiratory pressure is too high, or the end-expiratory flow is too low. This will trigger the ventilator’s “Exhalation Obstructed” alarm.
An obstruction of expiratory flow results in inadequate ventilation and impaired gas exchange. Acute respiratory compromise due to impaired exhalation may result in inadequate ventilation and oxygen desaturation (hypoxemia).
As of May 13, Hamilton Medical has reported four serious injuries and no deaths associated with this issue.
Device Use
Hamilton Medical, Inc. ventilator coaxial breathing circuits are intended to connect HAMILTON-C1/T1/MR1 ventilators to a patient tube or respiratory mask during ventilation.
Contact Information
Customers in the U.S. with adverse reactions, quality problems, or questions about this issue should contact Hamilton Medical at [email protected] or call 1-800-426-6331.
Unique Device Identifier (UDI)
The unique device identifier (UDI) helps identify individual medical devices sold in the United States from manufacturing through distribution to patient use. The UDI allows for more accurate reporting, reviewing, and analyzing of adverse event reports so that devices can be identified, and problems potentially corrected more quickly.
How do I report a problem?
Health care professionals and consumers may report adverse reactions or quality problems they experienced using these devices to MedWatch: The FDA Safety Information and Adverse Event Reporting Program.
Article source: http://www.fda.gov/medical-devices/medical-device-recalls-and-early-alerts/early-alert-breathing-circuit-set-issue-hamilton-medical