Aim. To evaluate dynamic changes in the lungs, hemostasis system, immune system in different terms after coronavirus pneumonia. Materials and methods. Ventilation-perfusion single-photon emission computed tomography/computed tomography (CT), functional methods of lung investigation, evaluation of hemostasis system, immune status and specific humoral immune response were performed and evaluated in different terms after coronavirus pneumonia. A total of 71 patients were examined according to this protocol. We examined patients with the lesion volume not less than 50% according to chest CT. All patients were divided into 2 groups depending on the distance from the acute stage of coronavirus pneumonia. Group 1 included patients who were examined early (3060 days after hospital discharge), group 2 included patients who were examined later (61180 days after hospital discharge). Results. We obtained gradual regression of pathologically-modified tissue from 67.3% during the inpatient phase to 30.9% during the early period and to 19.7% during the late period of examination, according to CT scan of the chest organs. The same tendency was demonstrated by diffusion capacity of the lungs. Perfusion scintigraphy data showed a decrease in perfusion deficit from 26.012.8% during the early period of examination to 19.46.2% during the late period of examination. On the contrary, ventilatory scintigraphy demonstrates the increase of isotope passage time through the alveolar-capillary membrane over time (from 48.231.3 minutes in the early period to 83.637.2 minutes in the late period). An increase in D-dimer was detected in 24% of patients in the early group. The levels of inflammatory markers, indices of immune status, and specific humoral immune response did not differ in the two described groups. Conclusion. The results demonstrate gradual regression of pathological changes caused by coronavirus infection.

The article presents a comparative retrospective analysis of clinical, laboratory data and outcomes in 39 patients with severe COVID-19 complicated by acute respiratory distress syndrome, who received high-flow oxygen therapy. Of which, 19 patients additionally received 75 mg of inhaled surfactant BL twice daily for 5 days using a nebulizer. As a result, mortality rate in the group of patients receiving surfactant was 10.5%, while in the standard therapy group — 50%; the number of patients transferred to the mechanical ventilation was 21% and 70%, respectively. As the patients receiving the surfactant were injected with COVID-19 hyperimmune convalescent plasma and monoclonal antibodies to interleukin-6 receptors more often than those from the control group, we recalculated the results regardless of these patients. However, a significant difference between the mechanical ventilation rate (2.5 times less often in the surfactant group) and mortality rate (3.5 times less in the surfactant group) was observed. The duration of hospitalization and stay at the intensive care unit was not significantly different between patients with and without surfactant treatment. Inhalation therapy with surfactant BL was well tolerated even by patients with chronic obstructive pulmonary disease. In no case did therapy have to be stopped due to side effects, the most common of which was coughing during inhalation. This retrospective analysis shows that the prescription of an inhaled surfactant prior to transferring patients to mechanical ventilation can prevent the progression of respiratory failure, put down mechanical ventilation, and improve survival.