Interview with Marcel Filoche, Bruno Louis’ team in the France Culture program “La méthode scientifique” on the benefits of Surfactant Substitution Therapy in patients with severe COVID-19 and who develop an Acute Respiratory Distress Syndrome (ARDS)

In the deepest parts of the pulmonary air shaft, gas exchange between air and blood takes place within about 500 million alveoli (small spherical chambers about 1/4 mm in diameter). The surface of these alveoli, whose developed surface is of the order of 100 m^2 in the adult, is lined with a liquid layer itself covered with a thin film of surfactant. This surfactant is a chemical substance produced in situ and similar to soap, whose role is to considerably reduce the air-water surface tension and consequently the energy necessary for the regular inflation-deflation of the lung. Its presence is essential for proper breathing and its absence in the very premature infant is responsible for Infant Respiratory Distress Syndrome (IRDS).

In adults, generalized inflammation of the alveolar wall induces an influx of inflammatory fluid, proteins and biological debris into the alveolus. This condition, known as Acute Respiratory Distress Syndrome (ARDS), destroys the surfactant barrier and respiratory function. In particular, patients with severe COVID-19 develop ARDS, which can ultimately lead to patient asphyxiation. The therapy presented in the report, Surfactant Replacement Therapy, consists of instilling a surfactant solution into the trachea of the intubated and mechanically ventilated patient. This liquid solution spreads through the bronchial tree to finally reach the alveolar area and help restore respiratory function. Our work models this propagation. Our numerical simulations have shown that this propagation, if it leads to a homogeneous and efficient administration in the newborn for a wide range of parameters, is much more problematic in adults and requires a fine optimization. These studies have contributed to revisiting past clinical failures, notably by significantly increasing the volumes of solutions instilled. A randomized trial in collaboration with the Poissy and Mantes-la-Jolie Hospitals and the Saint-Joseph Hospital in Paris is currently underway on severe COVID-19 patients.

Find the interview (in french) of Marcel Filoche broadcasted on Thursday, January 14, 2021 by following this link :
https://www.franceculture.fr/emissions/la-methode-scientifique/la-methode-scientifique-emission-du-jeudi-14-janvier-2021 (the beginning of his interview is around the 43rd minute)