The role of exogenous surfactant in the treatment of respiratory viral infections

Pulmonary surfactant is a complex substance with high surface activity that prevents alveoli collapse at the end of expiration and, therefore, stabilizes the lung volume and the gas exchange. These properties of surfactant opened the way for its investigation in the respiratory distress syndrome of newborn and the acute respiratory distress syndrome (ARDS) in adults including patients with severe virus-associated and bacterial pneumonias. This paper is a review of published laboratory data and clinical findings on the efficacy of surfactant in adults. Several authors demonstrated that exogenous surfactant could improve mortality in patients with ARDS, reduce the need in mechanical ventilation and a length of hospitalization in general. Most clinical trials of surfactant were related to the novel coronavirus infection COVID-19, but several papers included patient with severe pneumonia associated with influenza or respiratory syncytial virus. Moreover, surfactant could be useful for better delivery of pharmacological agents, including antibiotics, in the distal airways and the lung tissue in patients with bacterial pneumonia. Unfortunately, current findings are scarce to certainly detecting a role of exogenous surfactant in the management of such patients. Further studies of clinical efficacy of exogenous surfactant in severe lung injury are required.