# Intra-hospital transport of adult critically ill patients treated with high flow nasal cannula oxygen: a prospective observational multicenter study

## TL;DR

This study examines the safety of using high-flow nasal cannula oxygen during hospital transports of critically ill patients, finding few severe complications.

## Contribution

The study provides empirical evidence on the safety profile of transportable high-flow nasal cannula oxygen therapy during intra-hospital transport of critically ill patients.

## Key findings

- Only 4.3% of transports experienced severe adverse events, primarily transient hypoxemia.
- Non-severe adverse events occurred in 23% of transports, including increased oxygen fraction requirements and device dysfunction.
- Severe adverse events were observed only during the first transport of affected patients.

## Abstract

Acute respiratory failure is a common reason for admission to the intensive care unit, and patients are frequently treated with high-flow nasal cannula oxygen therapy (HFNC). Intra-hospital transport of critically ill patients, such as between hospital wards and the intensive care unit or for diagnostic exams, is common. Transportable HFNC can be used during these intra-hospital transports. We aimed to evaluate the complications associated with intra-hospital transport of patients treated with HFNC.

We conducted a prospective, descriptive multicenter study between May 2022 and May 2024, involving critically ill adult patients who were treated with HFNC prior to transport and required intra-hospital transport for any reason, accompanied by an intensive care unit team. The primary objective was to evaluate the incidence of severe adverse events including severe hypoxemia (with pulse oxygen saturation of less than 80%), need for intubation, need for non-invasive ventilation or cardiorespiratory arrest during transport. Secondary objectives were to assess the incidence of non-severe adverse events, defined as the need for increased inspired oxygen fraction, switching HFNC for standard oxygen therapy, nasal cannula removal or dysfunction of the HFNC device.

We included 165 patients and analyzed 187 transports. Eight (4.3%) severe adverse events occurred in 7 patients including 6 cases of severe transient hypoxemia and 2 cases of non-invasive ventilation. All of them were transient severe hypoxemia that occurred during the first transport. Forty-three (23%) non-severe adverse events occurred, including 29(15.6%) cases of increased inspired oxygen fraction requirement, 7/187 (3.74%) cases of nasal cannula removal, 6/187 (3.2%) cases of HFNC device dysfunction, and 1 (0.5%) case involved replacing HFNC with standard oxygen therapy.

HFNC during intra-hospital transport of critically ill patients had a low incidence of severe adverse events. Non-severe adverse events were more frequent, but their potential impact could not be assessed in this study and warrants further investigation.

Trial registration: Clinicalstrials.gov, NCT05311007, registered 23 March 2022, https://clinicaltrials.gov/study/NCT05311007?term=hospiflow&rank=1.

The online version contains supplementary material available at 10.1186/s13613-025-01502-7.