High-Flow Oxygen Therapy Can Boost Exercise for Select IPF Patients
Supplementary oxygen using a high‐flow nasal cannula boosts exercise endurance more effectively than standard devices in idiopathic pulmonary fibrosis (IPF) patients with suboptimal blood-oxygen levels, a small trial reported.
The study, “Impact of high-flow oxygen therapy during exercise in idiopathic pulmonary fibrosis: a pilot crossover clinical trial,” was published in the journal BMC Pulmonary Medicine.
Standard oxygen therapy (SOT), using a regular nasal cannula — a flexible tube whose two open prongs sit inside the nostrils — or a mask, has been shown to enhance exercise capacity and endurance in IPF patients. However, SOT has well recognized limitations in maintaining optimal oxygen levels during exercise with these patients.
High‐flow nasal cannula oxygen therapy (HFNC) — which delivers heated and humidified oxygen at flow rates of up to 60 liters/minute — was shown to improve endurance and maintain appropriate blood-oxygen levels during exercise in people with chronic obstructive pulmonary disease (COPD), another chronic lung disease, when compared with a standard nasal cannula.
Whether HFNC would also benefit IPF patients remains unknown.
Researchers in Spain conducted a prospective, crossover trial (NCT04564664) to assess and compare the ability of high‐flow nasal cannula oxygen therapy, relative to standard oxygen therapy, at enhancing endurance in IPF patients during a cardiopulmonary exercise.
They enrolled 10 IPF patients (nine men; mean age of 71.7 years; eight former smokers) with low blood-oxygen levels during the six-minute walking test (6MWT), a test that assesses exercise capacity and endurance.
At the trial’s start (baseline measure), their mean oxygen saturation (SpO2) — a parameter that measures the amount of oxygen carried by red blood cells — was equal to or below 85% during the walking test.
A first incremental cardiopulmonary exercise test was performed to evaluate patients’ maximum exercise capacity and set up the oxygen supplementation necessary to maintain an SpO2 above 85% with a Venturi mask, a low-flow oxygen mask.
Following this initial test, patients performed other two exercise rounds, with oxygen being given via HFNC or SOT (five patients each).
The trial’s main goal was to compared endurance time in each group. Additional goals included assessing muscle oxygen saturation (StO2), as well as respiratory and leg symptoms.
All 10 people completed the trial, with no adverse events reported. Their average 6MWT distance at baseline was 436 meters, with a mean SpO2 of 81%.
During the incremental cardiopulmonary exercise, endurance time was significantly greater in the HFNC patient group compared with those given SOT (mean of 494 vs. 381 seconds, or roughly 8.23 minutes vs. 6.35 minutes). This corresponded to a 30% difference favoring high‐flow nasal cannula oxygen therapy.
HFNC was also associated with a significantly greater boost in inspiratory capacity at the trial’s end compared with standard oxygen therapy (19.4% vs. 7.1%).
A similar trend was observed in StO2 levels during a free-pedaling exercise (10.6% for HFNC vs 9.6% with SOT).
No differences were found in respiratory or leg symptoms between the two oxygen-delivery devices.
“This is the first study demonstrating that HFNC oxygen therapy improves exercise tolerance better than SOT in IPF patients” with low oxygen levels during exercise, the researchers wrote. “HFNC appears as an excellent option to give oxygen supplementation during exercise to IPF patients.”
Still, more and larger “studies are needed to confirm the benefits of HFNC in IPF patients and its potential usefulness in rehabilitation programs,” they added.