High-dose Inhalations of Nitric Oxide in the Treatment of Pneumonia

Inclusion Criteria: 1. An established diagnosis of Nosocomial Pneumonia (NP) after cardiac surgery under cardiopulmonary bypass (CPB) or hospitalization for Community-acquired pneumonia (CAP). 2. Spontaneous breathing. 3. Age \> 18 years. 4. Signed informed consent. 5. Negative result of immunochromatographic Severe acute respiratory syndrome-related coronavirus 2 rapid antigen test on the day of diagnosis of pneumonia. Diagnostic criteria for NP The diagnosis of NP is considered established when the number of points on the Clinical Pulmonary Infection Score (CPIS) is greater than 6: Diagnostic criteria for CAP: Radiologically confirmed focal pulmonary opacity and at least 2 clinical symptoms and signs of the following: 1. acute fever at the onset of the disease (t° \> 38.0°C); 2. cough with sputum; 3. physical signs (crepitus/fine rales, bronchial breathing, shortening of percussion sound); 4. leukocytosis \> 10x109/l and/or left shift (\> 10%) Exclusion Criteria: 1. Diagnosed infectious process of another localization (surgical site infection (SSI), acute and chronic urinary tract infection (active), catheter-related bloodstream infection, peritonitis, infective endocarditis etc.). 2. Mechanical ventilation 3. Presence of tracheostomy 4. Patient's participation in another clinical trial at the time of screening or within the previous 3 months. 5. Concomitant pulmonary disease with the need for respiratory support before the development of pneumonia. 6. History of malignancy or other irreversible diseases/conditions with a life expectancy of less than 1 year. 7. Presence of HIV infection