# Effect of HIgh-Flow Therapy in Long-Term Oxygen Therapy (HILOT): study protocol for a multicentre, registry-based, randomised clinical trial

## TL;DR

This study tests whether adding high-flow oxygen therapy to standard oxygen therapy improves outcomes for people with chronic respiratory failure.

## Contribution

A multicenter trial comparing high-flow oxygen therapy with standard therapy in patients with COPD or ILD.

## Key findings

- The trial will assess time to hospitalization or death in COPD patients using high-flow oxygen therapy.
- Secondary outcomes include health-related quality of life and economic impacts.
- Results will explore HFOT effects in interstitial lung disease patients.

## Abstract

The use of high-flow oxygen therapy (HFOT) compared with standard low-flow oxygen therapy (LFOT) may improve outcomes in people with oxygen-dependent chronic respiratory failure (CRF). The primary aim of this multicentre trial was to evaluate HFOT in addition to LFOT, compared with regular LFOT in people with CRF due to chronic obstructive pulmonary disease (COPD) or interstitial lung disease (ILD).

Registry-based randomised controlled trial (R-RCT) of people on LFOT for CRF due to COPD (n = 270) and ILD (n = 40), at ten Swedish secondary care centres within the Swedish Register for Respiratory Failure (Swedevox). People with ongoing LFOT are randomised in a 1:1 ratio to standard treatment with LFOT (control) or LFOT with added HFOT during nighttime and at the patient’s discretion daytime (intervention). HFOT is provided using the ResMed Lumis HFT system and the AcuCare HFNC Cannula. Primary outcome is time to first hospitalisation or death up to 1 year in people with COPD. Secondary outcomes include symptoms, health-related outcomes (HRQL), health-economics, adverse events, and to explore the effects of HFOT in people with CRF due to ILD. Outcome data will be obtained from national registries and from patient questionnaires at 3 and 12 months.

This R-RCT will combine the advantages of a prospective randomised trial and large clinical national registries to improve the evidence-based use of long-term oxygen therapy. Recruitment started in June 2024 and is ongoing.

ClinicalTrials.gov, ID: NCT06247397. Registered 2024–02–07.

The online version contains supplementary material available at 10.1186/s13063-026-09488-8.