The impact of high-flow nasal cannula oxygen therapy on exercise capacity in fibrotic interstitial lung disease: a proof-of-concept randomized controlled crossover trial

Abstract

Background: Patients with fibrotic interstitial lung disease (FILD) often experience gas exchange abnormalities and ventilatory limitations, resulting in reduced exercise capacity. High-flow nasal cannula (HFNC) oxygen therapy is a novel treatment, whose physiological beneficial effects have been demonstrated in various clinical settings. We hypothesized that HFNC oxygen therapy might be superior to conventional oxygen therapy for improving exercise capacity in FILD patients. Methods: We performed a prospective randomized controlled crossover trial with a high-intensity constant work-rate endurance test (CWRET) using HFNC (50 L/min, FiO 2 0.5) and a venturi mask (VM) (15 L/min, FiO 2 0.5) for oxygen delivery in FILD patients. The primary outcome variable was endurance time. The secondary outcome variables were SpO 2 , heart rate, Borg scale (dyspnea and leg fatigue), and patient's comfort. Results: Seven hundred and eleven patients were screened and 20 eligible patients were randomized. All patients completed the trial. The majority of patients were good responders to VM and HFNC compared with the baseline test (VM 75%; HFNC 65%). There was no significant difference in endurance time between HFNC and VM (HFNC 6.8 [95% CI 4.3-9.3] min vs VM 7.6 [95% CI 5.0-10.1] min, p = 0.669). No significant differences were found in other secondary endpoints. Subgroup analysis with HFNC good responders revealed that HFNC significantly extended the endurance time compared with VM (VM 6.4 [95%CI 4.5-8.3] min vs HFNC 7.8 [95%CI 5.8-9.7] min, p = 0.046), while no similar effect was observed in the VM good responders. Conclusions: HFNC did not exceed the efficacy of VM on exercise capacity in FILD, but it may be beneficial if the settings match. Further large studies are needed to confirm these findings.

Impact of high-flow oxygen therapy during exercise in idiopathic pulmonary fibrosis: a pilot crossover clinical trial

“…Moreover, in subjects with stable COPD and severe ventilatory limitation for instance, the use of HFNC can better improve endurance time and blood oxygen saturation during exercise than SOT [ 14 ]. In contrast, these higher benefits did not appear to be present in a previous study that compared HFNC and SOT in an heterogeneous group that included different interstitial lung diseases [ 15 ]. However, there is a complete lack of previous studies assessing the potential advantages of HFNC in IPF in particular.…”

“…There is only one previous paper, published by Suzuki et al, that approximates the usefulness of HFNC in ILD patients during exercise [ 15 ]. They also performed a randomized crossover study using HFNC versus SOT in a mixed pool of different fibrotic ILD patients who have in common that they reached a very low SpO 2 (< 88%) during an incremental CPET.…”

“…They also performed a randomized crossover study using HFNC versus SOT in a mixed pool of different fibrotic ILD patients who have in common that they reached a very low SpO 2 (< 88%) during an incremental CPET. However, they found no differences among both methods in the whole group, probably due to its great heterogeneity [ 15 ]. Interestingly, when they performed a post-hoc analysis, they identified a subgroup of patients that were ‘better responders’ to HFNC than to SOT.…”

“…Based on previous studies, a sample size of at least 8 subjects was required to detect a mean difference in Tlim equal or higher than 33% between HFNC and SOT [ 23 ], considering a 20% dropout rate [ 15 , 23 , 24 ]. Categorical variables were expressed as frequencies and continuous variables as mean and standard deviation (SD) or median and 25, 75 percentiles (p25–p75).…”

Respiratory Impairment, Limited Activity, and Pulmonary Rehabilitation in Patients with Interstitial Lung Disease

“…It is expected that these effects are useful for preventing severe EIH and reducing the effort of breathing during exercise (Fig. 3) Cirio et al 31) have evaluated the effects of the administration of oxygen using HFNC in patients with COPD during exercise and reported that EIH and dyspnea were sig- nificantly reduced and oxygen therapy using HFNC allowed the patients to exercise for a longer time with a higher exercise intensity A randomized controlled crossover trial 32 ) was conducted to compare the effects of HFNC (50 L/min; FIO2 0.5) on exercise endurance time, SpO2, and dyspnea with those of oxygen therapy using a Venturi mask (15 L/min; FIO2 0.5) in patients with fibrotic ILD. They reported no significant differences in endurance time, SpO2, and dyspnea between HFNC and Venturi mask.…”