Philips Respironics has issued a new Urgent Medical Device Correction Letter to healthcare professionals regarding an issue with its Trilogy EV300, Trilogy Evo O2, and Trilogy Evo Universal ventilators, which could pose a risk for patients if not mitigated.

Philips Respironics discovered that the accuracy of delivered oxygen from the ventilators may deviate below the required tolerance of 5% from set point when providing high-concentration oxygen therapy, according to the letter. Additionally, the internal FiO2 sensor may indicate a value higher than the device is actually delivering. This may vary based on the patient’s lung capacity, lung resistance, use of a particulate filter, or circuit configuration, which may lead to under-delivery of oxygen. 

“Philips Respironics has assessed the issue and has determined that across the range of tested conditions the following hazard could be present for the most vulnerable patient populations that use these devices,” the letter reads. “If actual oxygen delivery deviates from the prescribed concentration, beyond the labeled tolerance of 5%, and the patient is not appropriately monitored, the patient may experience oxygen desaturation or hypoxemia.”

The potential hazard is most likely to occur when the Trilogy EV300, Trilogy Evo O2, or Trilogy Evo Universal high-pressure oxygen blending module (OBM) is used to manage patients requiring high volumes of oxygen such as scenarios requiring FiO2 setpoint greater than or equal to 70%.

Philips Respironics says it will release a software update to address the issue, which will be available free of charge for the devices mentioned in the letter. Additional details will be provided when the update is available. 

The devices as mentioned earlier can continue to be safely used in line with the mitigations described within the letter and in accordance with the Instructions for Use.