In late November, ResMed issued a safety notice warning that some of the masks used with its CPAP machines contain magnets that could potentially interfere with pacemakers, neurostimulators and other implanted medical devices—an issue that has also plagued competitor Philips. In the weeks since, ResMed has upgraded the warning to a full-on field correction, which has in turn, like Philips’ own magnet-related safety event, earned the FDA’s most serious recall rating.
The regulator publicized the Class I categorization in a notice Thursday, indicating a heightened risk of injury or death associated with use of the affected devices.
To date, according to the notice, a total of six injuries have been reported in connection with the safety issue—up from the five reports of harm that ResMed tallied in its original November warning—with no reported deaths.
The recall concerns several models of ResMed’s AirFit and AirTouch masks, more than 20.4 million of which have been sold in the U.S. alone.
The masks are meant to be used by people who weigh at least 66 pounds and who have been prescribed either CPAP or BiPAP therapy, for either in-hospital or at-home use. The affected models all include magnets on their headgear straps and on the masks’ frame connections to simplify the process of attaching and adjusting the masks.
The magnets are strong enough, however, that if they come within a few inches of certain medical devices, they could potentially cause the devices to malfunction or physically shift positions. When those changes occur in often-life-sustaining devices like pacemakers, implantable cardioverter defibrillators, neurostimulators, insulin pumps, stents, ocular implants and more, they could lead to serious harm or even death.
ResMed’s global field action isn’t an all-out recall in the traditional sense of the word: Though users who are contraindicated for continued use of the masks should return them to the company, others are simply being alerted to updates to the masks’ user guides.
Those updates include a more detailed list of contraindications, outlining the many metallic and other medical implants that may interact with the magnets. If a user or someone with whom they may come in close physical contact actively use the devices, they should replace the mask with one that doesn’t contain magnets.
ResMed also updated a warning issued alongside the masks, explaining that the magnetic pieces should be kept at least six inches away from any medical devices that could potentially be affected by magnetic interference. The company has advised individuals to check with their doctors or the manufacturers of their implanted devices to verify whether they could have an adverse reaction to the magnets.
ResMed outlined the changes in a letter (PDF) sent to patients in November, in which it highlighted the fact that it has only received a handful of injury reports—none of them detailing permanent injuries or death—among the “tens of millions of masks with magnets” that it has sold globally since 2014.