Prospective Validation of the ROX Index

Prospective Validation of the ROX Index Utility in Predicting Failure of HFNC Treatment in Patients With Acute Respiratory Failure

We recently described the ROX index, defined as the ratio of SpO2/FIO2 to respiratory rate that outperformed the diagnostic accuracy of the two variables separately. Patients who had a ROX index ≥4.88 after 12 hours of HFNC therapy were less likely to be intubated, even after adjusting for potential covariates. Like any other scoring system, an independent validation of the score in a different population is necessary. We therefore undertook a multicenter, prospective study to validate the ROX index's diagnostic accuracy for determining which patients will fail on HFNC and will need to be intubated.

Study Overview

• Status: Completed
• Conditions: Validation

Detailed Description

A growing interest in the non-invasive management of acute respiratory failure has been fuelled by the advent of high-flow nasal canula oxygen therapy (HFNC) and recent data showing that use of HFNC was associated with lower mortality, more ventilator-free days and lower risk for intubation in subsets of patients with PaO2/FIO2≤200mmHg or in those who were immunocompromised in comparison with non-invasive ventilation or standard oxygen. These positive results in favour of HFNC followed physiological studies indicating oxygenation and comfort improvements associated with HFNC use. This has led clinicians to try this technique in the most severe respiratory failure patients, those with ARDS.

Consubstantial to the increasing use of HFNC is the risk of delaying intubation. This is a major concern since a large body of evidence has shown that patients that fail non-invasive ventilatory management of de novo acute respiratory failure (ARF) have a worse outcome.

The variability in both the decision to intubate and its timing reported in several studies suggest that clinical parameters such as respiratory parameters alone are not sufficient and that the progression of the respiratory failure is not sufficiently taken into account. To address this need, we investigated a new score to identify patients at risk of intubation to help clinicians, with three goals simple to use, accurate, and immediately performable at the patients' bedside by any staff.

• Study Type: Observational
• Enrollment (Actual): 191

Contacts and Locations

Study Locations

• France
  • Clamart, France, 92140
    • Hôpital Antoine Béclère, Service de Réanimation polyvalente et surveillance continue
  • Colombes,, France, 92700
    • Hôpital Louis Mourier, Service de Réanimation Médico-Chirurgicale
• Spain
  • Barcelona, Spain
    • Hospital del Mar
  • Barcelona, Spain, 08035
    • Hospital Universitari Vall d'Hebron. Universitat Autonoma de Barcelona
  • Toledo, Spain
    • Virgen de la Salud University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients admitted to the ICU with pneumonia and treated with HFNC were included

Description

Inclusion Criteria:

- All consecutive patients admitted to the ICU with pneumonia and treated with HFNC were included

Exclusion Criteria:

• Patients younger than 18 years old
• Patients with indication for immediate intubation
• Patients with limitation of therapeutic effort
• Patients electively intubated for diagnostic or therapeutic procedures

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
HFNC failure; requiring intubation and invasive mechanical ventilation
HFNC success; not requiring intubation nor invasive mechanical ventilation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HFNC failure	HFNC failure was defined as need for invasive mechanical ventilation	Through study completion (an average of 60 days)

Collaborators and Investigators

• Sponsor: Hospital Universitari Vall d'Hebron Research Institute
• Investigators: Study Director: Oriol Roca, MD PhD, Vall D'Hebron University Hospital

Publications and helpful links

General Publications

• Frat JP, Thille AW, Mercat A, Girault C, Ragot S, Perbet S, Prat G, Boulain T, Morawiec E, Cottereau A, Devaquet J, Nseir S, Razazi K, Mira JP, Argaud L, Chakarian JC, Ricard JD, Wittebole X, Chevalier S, Herbland A, Fartoukh M, Constantin JM, Tonnelier JM, Pierrot M, Mathonnet A, Beduneau G, Deletage-Metreau C, Richard JC, Brochard L, Robert R; FLORALI Study Group; REVA Network. High-flow oxygen through nasal cannula in acute hypoxemic respiratory failure. N Engl J Med. 2015 Jun 4;372(23):2185-96. doi: 10.1056/NEJMoa1503326. Epub 2015 May 17.
• Roca O, Messika J, Caralt B, Garcia-de-Acilu M, Sztrymf B, Ricard JD, Masclans JR. Predicting success of high-flow nasal cannula in pneumonia patients with hypoxemic respiratory failure: The utility of the ROX index. J Crit Care. 2016 Oct;35:200-5. doi: 10.1016/j.jcrc.2016.05.022. Epub 2016 May 31.
• Frat JP, Ragot S, Coudroy R, Constantin JM, Girault C, Prat G, Boulain T, Demoule A, Ricard JD, Razazi K, Lascarrou JB, Devaquet J, Mira JP, Argaud L, Chakarian JC, Fartoukh M, Nseir S, Mercat A, Brochard L, Robert R, Thille AW; REVA network. Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy. Crit Care Med. 2018 Feb;46(2):208-215. doi: 10.1097/CCM.0000000000002818.
• Roca O, Caralt B, Messika J, Samper M, Sztrymf B, Hernandez G, Garcia-de-Acilu M, Frat JP, Masclans JR, Ricard JD. An Index Combining Respiratory Rate and Oxygenation to Predict Outcome of Nasal High-Flow Therapy. Am J Respir Crit Care Med. 2019 Jun 1;199(11):1368-1376. doi: 10.1164/rccm.201803-0589OC.

Study record dates

Study Major Dates

• Study Start: May 1, 2016
• Primary Completion (Actual): May 1, 2017
• Study Completion (Actual): September 1, 2017

Study Registration Dates

• First Submitted: July 5, 2016
• First Submitted That Met QC Criteria: July 26, 2016
• First Posted (Estimate): July 27, 2016

Study Record Updates

• Last Update Posted (Actual): August 12, 2019
• Last Update Submitted That Met QC Criteria: August 9, 2019
• Last Verified: March 1, 2018

More Information

Terms related to this study

• Keywords: high-flow nasal cannula, HFNC, acute respiratory failure, intubation
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency
• Other Study ID Numbers: PR(AG)206/2016

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No