FDA Sets a Class II Path for Hyperoxia Monitors

A hospital-monitoring feature that reached the market through a one-off De Novo review three years ago now has a generic regulatory home. FDA's 6 October 2026 final order classifies the hyperoxia monitoring device adjunct to pulse oximetry as Class II, converting Masimo's 2023 De Novo grant into a predicate other sensor makers can cite through the ordinary 510(k) process.

What the order formalizes

FDA's De Novo pathway authorizes a specific device while, on its own, creating no generic type a competitor can point to as a predicate — that gap closes only when FDA follows up with a classification regulation. The 6 October order does that for hyperoxia monitoring adjuncts to pulse oximetry, codifying the device type at 21 CFR 870.2720 as Class II under product code QWE, with special controls carried over from the original De Novo review. The filing sits under FDA's Cardiovascular Devices panel in the Federal Register listing, the same administrative path FDA has used for a steady cadence of device-type classification orders throughout 2026, each one converting an earlier De Novo grant into a standing predicate.

The device behind the classification

The classification traces directly to Masimo's ORi (Oxygen Reserve Index) feature, which received De Novo authorization on 12 October 2023 under decision DEN200076 as the first device of its kind to reach market. ORi is intended for patients 18 years and older receiving supplemental oxygen during surgery, functioning as an adjunct to standard pulse oximetry by monitoring elevated hemoglobin oxygen saturation — a range standard SpO2 monitoring does not resolve well, since pulse oximetry saturates near 100% well before true hyperoxia develops. FDA's review describes the clinical value as earlier warning of impending oxygen desaturation, giving clinicians a signal before SpO2 itself would show one. It is explicitly not a stand-alone diagnostic device: arterial blood gas analysis remains the reference standard for diagnosing hypoxemia, and the device is meant to supplement, not replace, existing monitoring practice.

A caveat FDA's own review flagged

FDA's original De Novo review for this device type noted a specific limitation worth carrying forward into the classification: the agency said no analyses had been presented to assure the device's accuracy across patient subpopulations. That caveat lands in a charged context for pulse-oximetry-adjacent technology generally. FDA has conducted a broader, ongoing review of standard pulse oximeter accuracy across skin pigmentation, after published research found a pattern of positive bias — overestimating blood oxygen saturation — in patients with darker skin, a finding with direct implications for any device that relies on the same optical measurement principle. The classification order does not resolve that open question for hyperoxia-monitoring adjuncts specifically; it establishes the device type and its special controls without claiming the subpopulation-accuracy question has been answered.

What changes for competing sensor makers

Before this order, a company developing a competing hyperoxia-monitoring sensor had no established predicate to cite and would, in principle, have needed its own De Novo review — a more resource-intensive path than 510(k) clearance, which relies on demonstrating substantial equivalence to an existing, classified device type. With the Class II regulation now in place, a sponsor whose device is substantially equivalent to the classified type can instead pursue 510(k) clearance, provided it meets the special controls the order establishes. That is the practical function of a classification order: it does not change what Masimo's own device can do, but it lowers the regulatory barrier to entry for the next company building a similar one — the same mechanism FDA used this month for a separate hereditary-cancer DNA sequencing device type, and a pattern regulatory affairs teams tracking adjacent device categories should expect to recur as other recent De Novo grants reach their own classification orders.

Frequently asked questions

What did FDA publish on 6 October 2026?

A final order, "Medical Devices; Cardiovascular Devices; Classification of the Hyperoxia Monitoring Device Adjunct to Pulse Oximetry," FR Doc. 2026-20441. It establishes the device type as Class II under 21 CFR 870.2720, product code QWE, with special controls set out in the order.

What device created this classification?

Masimo's ORi (Oxygen Reserve Index) feature, authorized through FDA's De Novo pathway on 12 October 2023 under decision DEN200076 — the first marketing authorization for a device monitoring elevated hemoglobin oxygen saturation as an adjunct to standard pulse oximetry, intended for patients 18 and older receiving supplemental oxygen during surgery.

Why does a classification order matter if the device is already on the market?

A De Novo grant authorizes one device and creates no generic device type for a competitor to cite until a classification regulation follows. Publishing the Class II regulation establishes that generic type and predicate, so a sponsor with a substantially equivalent hyperoxia-monitoring sensor can now file a 510(k) rather than running its own De Novo review.

What limitations does FDA flag for this device type?

FDA's original De Novo review noted benefit in detecting impending oxygen desaturation and monitoring moderate hyperoxia, but also noted that no analyses had been shown to assure accuracy across patient subpopulations — relevant given FDA's broader, ongoing review of pulse oximetry accuracy across skin pigmentation, which has found a pattern of positive bias in darkly pigmented individuals for standard pulse oximetry technology.