{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T17:47:11Z","timestamp":1777312031642,"version":"3.51.4"},"reference-count":22,"publisher":"Hamad bin Khalifa University Press (HBKU Press)","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026]]},"abstract":"\n Background:<\/jats:bold>\n Acute respiratory distress syndrome (ARDS) remains a leading cause of mortality among critically ill patients with COVID-19. Inhaled nitric oxide (iNO), a selective pulmonary vasodilator, is often used as rescue therapy to improve oxygenation; however, its impact on survival remains uncertain.\n <\/jats:p>\n \n Objective:<\/jats:bold>\n To evaluate the clinical outcomes of iNO therapy in patients with COVID-19-related ARDS and to stratify patients into Early, Delayed, and Non-Responder groups based on the timing of their oxygenation response.\n <\/jats:p>\n \n Methods:<\/jats:bold>\n A retrospective cohort study of 99 patients with COVID-19-related ARDS who received iNO was conducted. Patients were categorized as:\n <\/jats:p>\n \n Early Responders:<\/jats:bold>\n \u226520% improvement in the PaO\n 2<\/jats:sub>\n \/FiO\n 2<\/jats:sub>\n ratio within 8 h;\n <\/jats:p>\n \n Delayed Responders:<\/jats:bold>\n \u226520% improvement in the PaO\n 2<\/jats:sub>\n \/FiO\n 2<\/jats:sub>\n ratio between 8 and 24 h;\n <\/jats:p>\n \n Non-Responders:<\/jats:bold>\n <20% improvement in the PaO\n 2<\/jats:sub>\n \/FiO\n 2<\/jats:sub>\n ratio within 24 h, including those who showed\n no improvement<\/jats:bold>\n in their PaO\n 2<\/jats:sub>\n \/FiO\n 2<\/jats:sub>\n ratio within 24 h of iNO initiation.\n <\/jats:p>\n Baseline demographics, comorbidities, and outcomes, including duration of mechanical ventilation, ICU and hospital length of stay, and mortality, were compared.<\/jats:p>\n \n Results:<\/jats:bold>\n Early and Delayed Responders showed significant improvement in oxygenation (mean PaO\n 2<\/jats:sub>\n \/FiO\n 2<\/jats:sub>\n : 137.3 vs. 126.9 vs. 106.4;\n p<\/jats:italic>\n = 0.004), with mean percentage increases of 65.3%, 56.6%, and 8.2%, respectively (\n p<\/jats:italic>\n < 0.001). However, this did not translate into differences in ICU mortality (64.8%, 62.5%, and 71.4%, respectively;\n p<\/jats:italic>\n = 0.81) or other hospital outcomes. Rates of acute kidney injury (AKI), methemoglobinemia, and other complications were comparable among the groups.\n <\/jats:p>\n \n Conclusion:<\/jats:bold>\n iNO improved oxygenation in a subset of patients with COVID-19-related ARDS but did not reduce mortality. Stratification by timing of response highlights patient heterogeneity and supports response-guided, time-limited use of iNO in critical care.\n <\/jats:p>","DOI":"10.5339\/qmj.2026.13","type":"journal-article","created":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T21:30:34Z","timestamp":1773696634000},"source":"Crossref","is-referenced-by-count":0,"title":["A retrospective evaluation of clinical outcomes in the use of inhaled nitric oxide in acute respiratory distress syndrome caused by COVID-19: The NITRICOVID study"],"prefix":"10.5339","volume":"2026","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3242-4217","authenticated-orcid":true,"given":"Mohamed Zuhail Kizhakka","family":"Peediyakkal","sequence":"first","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muna A Rahman","family":"Al Maslamani","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nevin","family":"Kannappilly","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Saifil","family":"Sidhique","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohamed","family":"Aboukamar","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sreekanth Komath","family":"Mohan","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jintu","family":"Iype","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Virendra Pratap","family":"Chaudhary","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ashib","family":"Thurakkal","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karimulla Shakeer","family":"Shaik","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Solaiman","family":"Allafi","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4845-4119","authenticated-orcid":true,"given":"Abdulqadir","family":"Nashwan","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nabeel F Suleiman","family":"Al LObaney","sequence":"additional","affiliation":[{"name":"Hamad Medical Corporation, Hamad Medical City, Doha, Qatar*Correspondance: Mohamed Zuhail Kizhakka Peediyakkal mpeediyakkal2@hamad.qa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"3277","reference":[{"issue":"(10229):","key":"B1","series-title":"Lancet","first-page":"1054\u201362","article-title":"Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: A retrospective cohort study","volume":"395","author":"Zhou\nF","year":"2020"},{"issue":"(1):","key":"B2","series-title":"Am J Respir Crit Care Med","first-page":"54\u201366","article-title":"Case fatality rates for patients with COVID-19 requiring invasive mechanical ventilation. 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