부산대학교 도서관

COVID-19-associated ARDS (cARDS) results from multiple pathogenetic mechanisms involving both parenchyma and circulation of the lungs. Despite authors described two pneumonia phenotypes according to lung elastance values, reported as Low and High phenotype, the evidence suggests that patients with cARDS have similar respiratory mechanics to patients with ARDS from other causes. Consequently, the proper management of patients with cARDS is the same as ARDS,consisting of protective mechanical ventilation strategy and prone position ventilation.However, the hypothesis that impaired alveolar perfusion could have a role in cARDS is interesting. Nitric oxide (NO) is a biatomic gaseous moleculeables to induce smooth muscle relaxation and vasodilation. So, inhaled nitric oxide (iNO) acts as a selective vasodilator because it only dilates vessels in areas participating in gas exchange, preserving hypoxic pulmonary vasoconstriction reflex and reducing ventilation/perfusion mismatch. With this narrative review we summarised the role of iNO for cARDS treatment to improve gas exchange. Furthermore, we briefly described its activity as an antiviral agent. In conclusion, although iNO administration can represent a valid theoretical therapeutic choice for the treatment of severe unresponsive hypoxemia in COVID-19 patients, data presented in the literature are scares and inconclusive, and several clinical trials are still ongoing. Further studies are needed to elucidate the pathogenetic mechanism of respiratory failure related to SARS-CoV-2 infection and inhaled NO role in patients with severe disease.