open access
Validity of ROX index in prediction of risk of intubation in patients with COVID-19 pneumonia
open access
Abstract
Introduction: One important concern during the management of COVID-19 pneumonia patients with acute hypoxemic respiratory failure is early anticipation of the need for intubation. ROX is an index that can help in identification of patients with low and those with high risk of intubation. So, this study was planned to validate the diagnostic accuracy of the ROX index for prediction of COVID-19 pneumonia outcome (the need for intubation) and, in addition, to underline the significant association of the ROX index with clinical, radiological, demographic data.
Material and methods: Sixty-nine RT-PCR positive COVID-19 patients were enrolled. The following data were collected: medical history, clinical classification of COVID-19 infection, the ROX index measured daily and the outcome assessment.
Results: All patients with severe COVID-19 infection (100%) were intubated (50% of them on the 3rd day of admission), but only 38% of patients with moderate COVID-19 infection required intubation (all of them on the 3rd day of admission). The ROX index on the 1st day of admission was significantly associated with the presence of comorbidities, COVID-19 clinical classification, CT findings and intubation (p ≤ 0.001 for each of them). Regression analysis showed that sex and ROX.1 are the only significant independent predictors of intubation [AOR (95% CI): 16.9 (2.4– 117), 0.77 (0.69–0.86)], respectively. Cut-off point of the ROX index on the 1st day of admission was ≤ 25.26 (90.2% of sensitivity and 75% of specificity).
Conclusions: ROX is a simple noninvasive promising tool for predicting discontinuation of high-flow oxygen therapy and could be used in the assessment of progress and the risk of intubation in COVID-19 patients with pneumonia.
Abstract
Introduction: One important concern during the management of COVID-19 pneumonia patients with acute hypoxemic respiratory failure is early anticipation of the need for intubation. ROX is an index that can help in identification of patients with low and those with high risk of intubation. So, this study was planned to validate the diagnostic accuracy of the ROX index for prediction of COVID-19 pneumonia outcome (the need for intubation) and, in addition, to underline the significant association of the ROX index with clinical, radiological, demographic data.
Material and methods: Sixty-nine RT-PCR positive COVID-19 patients were enrolled. The following data were collected: medical history, clinical classification of COVID-19 infection, the ROX index measured daily and the outcome assessment.
Results: All patients with severe COVID-19 infection (100%) were intubated (50% of them on the 3rd day of admission), but only 38% of patients with moderate COVID-19 infection required intubation (all of them on the 3rd day of admission). The ROX index on the 1st day of admission was significantly associated with the presence of comorbidities, COVID-19 clinical classification, CT findings and intubation (p ≤ 0.001 for each of them). Regression analysis showed that sex and ROX.1 are the only significant independent predictors of intubation [AOR (95% CI): 16.9 (2.4– 117), 0.77 (0.69–0.86)], respectively. Cut-off point of the ROX index on the 1st day of admission was ≤ 25.26 (90.2% of sensitivity and 75% of specificity).
Conclusions: ROX is a simple noninvasive promising tool for predicting discontinuation of high-flow oxygen therapy and could be used in the assessment of progress and the risk of intubation in COVID-19 patients with pneumonia.
Keywords
ROX index; COVIID-19; intubation risk


Title
Validity of ROX index in prediction of risk of intubation in patients with COVID-19 pneumonia
Journal
Advances in Respiratory Medicine
Issue
Article type
Research paper
Published online
2020-12-17
DOI
10.5603/ARM.a2020.0176
Keywords
ROX index
COVIID-19
intubation risk
Authors
Lucy Abdelmabood Suliman
Taha Taha Abdelgawad
Nesrine Saad Farrag
Heba Wagih Abdelwahab


- Zhu Na, Zhang D, Wang W, et al. A novel coronavirus from patients with pneumonia in China, 2019. N Engl J Med. 2020; 382(8): 727–733.
- Force ARDSDT, R. V. R. G. T. B. F. N. C. E. F. E., 2012. Acute respiratory distress syndrome: the Berlin Definition. : JAMA.
- Gattinoni L, Chiumello D, Caironi P, et al. COVID-19 pneumonia: different respiratory treatments for different phenotypes? Intensive Care Med. 2020; 46(6): 1099–1102.
- Anesi LG Coronavirus disease 2019 (COVID-19): Critical care and airway management issues in Manaker Finlay G, Bloom A (Eds) UptoDate. Available https://www.uptodate.com/contents/coronavirus-disease-2019-covid-19-critical-care-and-airway-management-issues/print. (Accessed on September 06. ; 2020.
- Rochwerg B, Solo K, Darzi A, et al. Update alert: ventilation techniques and risk for transmission of coronavirus disease, including COVID-19. Ann Intern Med. 2020; 173(6): W122.
- Roca O, Messika J, Caralt B, et al. Predicting success of high-flow nasal cannula in pneumonia patients with hypoxemic respiratory failure: The utility of the ROX index. J Crit Care. 2016; 35: 200–205.
- Roca O, Caralt B, Messika J, et al. An index combining respiratory rate and oxygenation to predict outcome of nasal high-flow therapy. Am J Respir Crit Care Med. 2019; 199(11): 1368–1376.
- Hill NS, Ruthazer R. Predicting outcomes of high-flow nasal cannula for acute respiratory distress syndrome. An index that ROX. Am J Respir Crit Care Med. 2019; 199(11): 1300–1302.
- Rodriguez M, Thille AW, Boissier F, et al. Predictors of successful separation from high-flow nasal oxygen therapy in patients with acute respiratory failure: a retrospective monocenter study. Ann Intensive Care. 2019; 9(1): 101.
- Blez D, Soulier A, Bonnet F, et al. Monitoring of high-flow nasal cannula for SARS-CoV-2 severe pneumonia: less is more, better look at respiratory rate. Intensive Care Med. 2020; 46(11): 2094–2095.