# Oxygen-Guided Therapy for Optimal Rehabilitation for Peripheral Artery Disease

> **NIH NIH R41** · INFRARED RX, INC. · 2021 · $247,303

## Abstract

SUMMARY / ABSTRACT:
Atherosclerotic peripheral arterial disease (PAD) of the lower extremity affects over 8.5
million Americans, including 25% of individuals over 80 years of age, and is typified by
debilitating leg pain when walking. Untreated, progressive disease results in unrelenting
rest pain, ulcers and limb loss.1 Treatment options are limited as revascularization
procedures are both expensive and associated with considerable morbidity and mortality
whereas pharmacologic therapy is only marginally effective. Supervised exercise
therapy, however, is a cost-effective, minimally invasive technique that has proven to be
as effective as revascularization for alleviating most common PAD symptoms. Supervised
exercise therapy sessions for claudication remain difficult for older adults because of pain
during treatment, indirect costs, geographic constraints, pandemic concerns, and
concomitant caregiver roles. Infrared Rx, Inc proposes to design and develop novel
technology to complement or replace supervised exercise rehabilitation for older adults
with PAD. This technology uses near infrared spectroscopy (NIRS) to measure limb
hypoxia in real time and thus provide high fidelity, actionable information that allows
patients to tailor their own exercise session based on visual or haptic user interfaces –
fostering increased adherence to both supervised and self-directed training sessions.
As the onset of hypoxia precedes claudication pain, NIRS affords a potential surrogate
for tissue ischemia during walking that can be used to direct exercise intensity. We have
demonstrated in a small, randomized clinical trial funded by the American Heart
Association that a NIRS guided exercise program can effectively improve 6-minute walk
times in patients with PAD, but without the debilitating pain of a traditional supervised
exercise program.6 This non-invasive, innovative technology has the potential to solve
specific challenges that limit the efficacy of supervised exercise therapy for aging adults
with PAD; its current form, however, still requires an onsite technician for monitoring
during training.
Our central hypothesis is that NIRS-guided exercise programs can improve
compliance with exercise prescriptions, decrease morbidity, and improve
independence in older Americans with PAD. The following proposal will establish the
foundation upon which we can develop a commercially viable software analysis platform
that allows older adults to engage in exercise with 1) minimal pain and 2) on a self-
directed basis. Successful development of this technology requires: 1) identification
of the technical parameters needed to reliably make accurate NIRS measurements
in older Americans with PAD; 2) automation of data-collection and analysis.

## Key facts

- **NIH application ID:** 10324798
- **Project number:** 1R41AG074788-01
- **Recipient organization:** INFRARED RX, INC.
- **Principal Investigator:** Kevin K. McCully
- **Activity code:** R41 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $247,303
- **Award type:** 1
- **Project period:** 2021-09-30 → 2023-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10324798

## Citation

> US National Institutes of Health, RePORTER application 10324798, Oxygen-Guided Therapy for Optimal Rehabilitation for Peripheral Artery Disease (1R41AG074788-01). Retrieved via AI Analytics 2026-06-03 from https://api.ai-analytics.org/grant/nih/10324798. Licensed CC0.

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