Oxygen Targets in Acute Heart Failure With Pulmonary Congestion (REDOX-AHF)

Copenhagen University Hospital, Hvidovre

Status and phase: Enrolling; Phase 3; Phase 2

Conditions: Acute Heart Failure; Hypoxemia; Pulmonary Congestion

Treatments: Drug: Oxygen

Study type: Interventional

Funder types: Other

Identifiers

NCT05613218

REDOX

Details and patient eligibility

About

This investigator-initiated, prospective, randomized, blinded, multi-center, controlled trial will investigate the effect of a restrictive vs. liberal oxygenation-strategy in patients hospitalized with acute heart failure with pulmonary congestion.

Patients will be randomized 1:1 in the emergency department to either liberal or restrictive oxygenation after providing informed written consent.

1. Liberal oxygenation group = SpO2 target of 96%.
2. Restrictive oxygenation group = SpO2 target of 90%.

The allocation will be concealed through the use of an oxygen-delivery robot, termed O2MATIC. The study will include 122 patients.

Full description

Background:

One million hospitalizations occur each year with a primary diagnosis of acute heart failure in the USA, with comparable numbers in Europe. Most patients with acute heart failure are treated with supplemental oxygen during hospitalization and guidelines recommend initiation of oxygen therapy if SpO2 <90% (class I, level C). However, no clinical trials of oxygen targets in humans with acute heart failure investigating clinically relevant endpoints have been performed.

Primary objective:

To investigate the effect of a restrictive vs. liberal oxygenation-strategy in patients hospitalized with acute heart failure.

Hypothesis:

Restrictive oxygenation is associated with improved clinical outcome compared to liberal oxygenation.

Design: Investigator-initiated, prospective, randomized, blinded, multi-center, controlled trial.

Intervention:

Patients will be randomized 1:1 in the emergency department to either liberal or restrictive oxygenation after providing informed written consent.

1. Liberal oxygenation group = SpO2 target of 96%.
2. Restrictive oxygenation group = SpO2 target of 90%.

Patients will have nasal cannula or oxygen mask placed as the usual care, and oxygen is titrated to the prespecified target range.

Consented patients will be randomly allocated to study groups via the automated web-based system within REDCap. The allocation will be concealed. Time at randomization will be considered as study time zero (T0). All patients will receive usual standard of care except for their oxygen-administration.

The intervention-phase will be 24 h, and hereafter oxygen therapy will be at the discretion of the treating physician.

Enrollment: 122 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age ≥ 18 years
2. Acute (within minutes to days) onset or worsening of subjective dyspnea
3. Oxygen saturation <92% (on arterial blood gas) or need of oxygen
4. At least one of the following clinical or radiological signs of congestion:

1. Pulmonary rales 2. Chest X-ray or CT with pulmonary congestion 3. Lung ultrasound with multiple B-lines

Exclusion criteria

1. More than 4 hours from hospital admission to randomization
2. Suspected infection or sepsis
3. Known severe pulmonary disease
4. Systolic blood pressure <90 mmHg

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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122 participants in 2 patient groups

Liberal oxygenation group

Active Comparator group

Description:

SpO2 target of 96%

Treatment:

Drug: Oxygen

Restrictive oxygenation group

Active Comparator group

Description:

SpO2 target of 90%.

Treatment:

Drug: Oxygen