Inhaled nitric oxide in patients with acute respiratory distress syndrome caused by COVID-19: treatment modalities, clinical response, and outcomes

DOI record: { "DOI": "10.1186/s13613-023-01150-9", "ISSN": [ "2110-5820" ], "URL": "http://dx.doi.org/10.1186/s13613-023-01150-9", "abstract": "<jats:title>Abstract</jats:title><jats:sec>\n <jats:title>Background</jats:title>\n <jats:p>Inhaled nitric oxide (iNO) has been widely used in patients with COVID-19-related acute respiratory distress syndrome (C-ARDS), though its physiological effects and outcome are debated in this setting. The objective of this cohort study was to describe the modalities of iNO use, clinical response, and outcomes in a large cohort of C-ARDS patients.</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Methods</jats:title>\n <jats:p>Multicentre, retrospective cohort study conducted in France.</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Results</jats:title>\n <jats:p>From end February to December 2020, 300 patients (22.3% female) were included, 84.5% were overweight and 69.0% had at least one comorbidity. At ICU admission, their median (IQR) age, SAPS II, and SOFA score were 66 (57–72) years, 37 (29–48), and 5 (3–8), respectively. Patients were all ventilated according to a protective ventilation strategy, and 68% were prone positioned before iNO initiation. At iNO initiation, 2%, 37%, and 61% of patients had mild, moderate, and severe ARDS, respectively. The median duration of iNO treatment was 2.8 (1.1–5.5) days with a median dosage of 10 (7–13) ppm at initiation. Responders (PaO<jats:sub>2</jats:sub>/FiO<jats:sub>2</jats:sub> ratio improving by 20% or more) represented 45.7% of patients at 6 h from iNO initiation. The severity of ARDS was the only predictive factor associated with iNO response. Among all evaluable patients, the crude mortality was not significantly different between responders at 6 h and their counterparts. Of the 62 patients with refractory ARDS (who fulfilled extracorporeal membrane oxygenation criteria before iNO initiation), 32 (51.6%) no longer fulfilled these criteria after 6 h of iNO. The latter showed significantly lower mortality than the other half (who remained ECMO eligible), including after confounder adjustment (adjusted OR: 0.23, 95% CI 0.06, 0.89, <jats:italic>p</jats:italic> = 0.03).</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Conclusions</jats:title>\n <jats:p>Our study reports the benefits of iNO in improving arterial oxygenation in C-ARDS patients. This improvement seems more relevant in the most severe cases. In patients with ECMO criteria, an iNO-driven improvement in gas exchange was associated with better survival. These results must be confirmed in well-designed prospective studies.</jats:p>\n </jats:sec>", "alternative-id": [ "1150" ], "article-number": "57", "assertion": [ { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Received", "name": "received", "order": 1, "value": "4 February 2023" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Accepted", "name": "accepted", "order": 2, "value": "7 June 2023" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "First Online", "name": "first_online", "order": 3, "value": "27 June 2023" }, { "group": { "label": "Declarations", "name": "EthicsHeading" }, "name": "Ethics", "order": 1 }, { "group": { "label": "Ethics approval and consent to participate", "name": "EthicsHeading" }, "name": "Ethics", "order": 2, "value": "This retrospective cohort study was submitted to Health Data Hub, the regulatory body in charge of validating projects carried out on existing databases in France, in April 2021. Included patients did not object to the use of their personal health data." }, { "group": { "label": "Consent for publication", "name": "EthicsHeading" }, "name": "Ethics", "order": 3, "value": "Not applicable." }, { "group": { "label": "Competing interests", "name": "EthicsHeading" }, "name": "Ethics", "order": 4, "value": "AMD, AVB, LP and AM received consulting fees from Air Liquide Healthcare, which funded the study. 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