Pulmonary surfactant in the complex treatment of severe pneumonia associated with COVID-19. Efficacy markers

Abstract

Aim: to evaluate the effect of pulmonary surfactant therapy in the complex treatment of severe community-acquired pneumonia caused by the SARS-CoV-2 on the disease course and outcome and to determine the possibility of using the level of surfactant protein D (surfactant protein D, SP-D) in blood serum as a criterion for the treatment efficacy. Patients and Methods: a prospective randomized study included 60 patients. Inclusion criteria confirmed SARS-CoV-2; bilateral pneumonia with at least grade 3 of lesion according to CT; SpO2 less than 92%. Patients were divided into two groups: group 1 (n=30) received surfactant therapy in addition to standard therapy, group 2 (n=30) received only standard therapy. Surfactant was administered by inhalation at a dose of 150–300 mg/day. The duration of surfactant therapy was 10 days. Arterial blood gas values, clinical parameters and SP-D levels were analyzed before and after treatment. Results: 48 hours after the therapy start, a statistically significant increase in SpO2 was registered in patients from group 1 versus an increase in patients from group 2 (p=0.048). On the 10th day of treatment, group 1 versus group 2 showed a statistically significant increase in the oxygenation index (PaO2/FiO2) (266.82±10.5 mmHg vs. 199.67±11.7 mmHg, respectively, p=0.001), a decrease in the frequency of artificial lung ventilation (ALV) (27% vs. 67%, respectively, p=0.002), length of hospital stay (21.0 (15;25) days vs. 27.0 (15;35) days, respectively, p=0.05). The fatal outcome was registered in 8 (27%) patients from group 1 and 18 (60%) patients from group 2 (p=0.001). Among patients from group 1 who had a favorable disease outcome, in 84% of cases surfactant therapy was prescribed in a shorter period from the disease onset versus patients whose treatment was ineffective (3±1.5 days vs. 7±2.0 days). A stable, reliable correlation was established between SP-D and PaO2 (r= 420, p=0.001), between SP-D and PaO2/FiO2 (r=460, p=0.001). Conclusion: the major effects of surfactant therapy are a faster recovery of the arterial blood gas, a decrease in the frequency of ALV, the length of hospital stay, and mortality. The success of surfactant therapy is associated with its early prescription. Surfactant therapy can be considered as an additional pathogenetically justified component in the complex treatment of severe pneumonia caused by the SARS-CoV-2. Significantly higher levels of SP-D were observed in patients with severe pneumonia associated with COVID-19, with the disease progression and adverse outcome. KEYWORDS: SARS-CoV-2, COVID-19, pneumonia, surfactant, artificial lung ventilation, respiratory failure, surfactant protein D, SP-D. FOR CITATION: Volchkova E.V., Alexandrovich Yu.S., Titova O.N. et al. Pulmonary surfactant in the complex treatment of severe pneumonia associated with COVID-19. Efficacy markers. Russian Medical Inquiry. 2022;6(7):352–359 (in Russ.). DOI: 10.32364/2587-6821-2022-6-7-352-359.