Hamilton Medical issues updated use instructions for certain breathing circuit sets after serious recall

Hamilton Medical has sent a letter to customers on May 18, 2026, advising updated use instructions for specific coaxial breathing circuit sets used with its HAMILTON-C1, HAMILTON T-1 and HAMILTON-MR1 ventilators.

The FDA classifies this recall as the most serious type, warning that continued use without following the new instructions could lead to serious injury or death. Users are instructed to verify unimpeded expiratory gas flow by ventilating a test lung after performing the pre‑operative test, and to review troubleshooting steps before further use.

The recall does not require removal of the devices from service; it only mandates adherence to the revised instructions. Affected products include several circuit and valve combinations identified by their product numbers and lot codes.