COPD Relief: High-Flow Nasal Device Boosts Walking Distance

Using a portable high-flow nasal device with humidified air improved walking distance and respiratory comfort for COPD patients in a preliminary study, without the need for supplemental oxygen.

A team of researchers at Nagasaki University Hospital is investigating whether a new portable nasal device can help people with chronic obstructive pulmonary disease (COPD) walk further with less breathlessness. The pilot trial, recently outlined in the *Journal of Thoracic Disease*, focuses on the AIRVO3™, a device that delivers heated, humidified air at a high flow rate through a nasal cannula.

COPD is a progressive lung disease marked by persistent airflow limitation and inflammation. A hallmark symptom is exertional dyspnea—severe breathlessness during physical activity—which leads to reduced exercise tolerance, physical inactivity, and a diminished quality of life. While long-term oxygen therapy is a cornerstone for patients with low blood oxygen, this study targets a different group: those who do not require supplemental oxygen but still struggle with shortness of breath during exertion.

The principle behind nasal high-flow (NHF) therapy is multifaceted. The high flow of gas helps wash out the anatomical dead space in the upper airways—the area where air is inhaled but doesn’t reach the gas-exchanging parts of the lungs. This makes each breath more efficient. It also provides a small degree of positive pressure in the airways, which can keep them open and reduce the effort required to breathe. Furthermore, the warm, humidified air is thought to improve the function of the cilia, the hair-like structures that help clear mucus.

“By using room air and focusing on high flow rather than high oxygen concentration, this study will clarify the pure effects of high-flow nasal therapy on exertional capacity,” explained the research team, led by Dr. Chikara Fukushima.

The study protocol describes a single-visit, crossover trial involving 20 patients with moderate to severe COPD. Each participant will perform two standardized 6-minute walk tests (6MWT) in a randomized order: one while using the portable AIRVO3 device and one without it. The primary measure of success is the distance walked in six minutes (6MWD).

Researchers will track a comprehensive set of secondary outcomes to paint a full picture of the device’s impact. These include:
* Oxygen saturation (SpO₂)
* Transcutaneous carbon dioxide levels (PtcCO₂)
* Respiratory and pulse rates
* The subjective experience of breathlessness, measured by the Borg dyspnea scale
* The time it takes for a patient’s oxygen level to drop below 90%, for their CO₂ to rise above a threshold, or for their breathing rate to become excessively high
* Patient-reported comfort and any subjective symptoms

Safety will be closely monitored, tracking incidents of low oxygen, any adverse events, device-related discomfort, and participant dropouts.

This pilot trial is a critical first step. If the portable NHF device is shown to be safe, effective, and acceptable to patients, it could become a valuable new tool. It may expand options for pulmonary rehabilitation programs and help individuals with COPD engage more confidently in the daily physical activity essential for managing their condition and maintaining independence.

**Sources:**
*Fukushima, C., et al. (2026). Safety and effectiveness of a portable nasal high-flow device for improving exercise tolerance in patients with chronic obstructive pulmonary disease: a study protocol for an open-label, randomized, crossover pilot trial. *Journal of Thoracic Disease*, 18(2), 175. https://doi.org/10.21037/jtd-2025-aw-2316*