Mary Wilson
Well-known member
Published: 10 July 2024
https://doi.org/10.3390/jpm14070738
Hua-Huy, Thông, Hà Pham-Ngoc, Frédérique Aubourg, Christine Lorut, Nicolas Roche, and Anh Tuan Dinh-Xuan
Abstract
Impaired lung gas exchange is commonly seen in patients with pulmonary involvement related to SARS-CoV-2 acute infection or post-acute COVID-19 syndrome (PACS). The primary aim of our study was to assess lung gas transfer, measuring the pulmonary diffusion capacity for nitric oxide (D[SUB]LNO[/SUB]) and carbon monoxide (D[SUB]LCO[/SUB]) in all COVID-19 patients. Our secondary aim was to decipher the respective roles of perturbed lung membrane conductance (D[SUB]M[/SUB]) and reduced pulmonary capillary volume (V[SUB]C[/SUB]) in patients with impaired lung gas exchange. From May to October 2020, we measured D[SUB]LNO[/SUB]-D[SUB]LCO[/SUB] in 118 patients during their post-COVID-19 period (4.6 months after infection) to decipher alveolo-capillary gas transfer disturbances. D[SUB]LNO[/SUB]-D[SUB]LCO[/SUB] measurement was also performed in 28 healthy non-smokers as controls. Patients were classified into three groups according to the severity (mild, moderate, and severe) of acute COVID-19 infection. Patients with mild COVID-19 had normal lung volumes and airways expiratory flows but impaired pulmonary gas exchange, as shown by the significant decreases in D[SUB]LNO[/SUB], D[SUB]LCO[/SUB], D[SUB]M[/SUB], and V[SUB]C[/SUB] as compared with controls. V[SUB]C[/SUB] was significantly impaired and the D[SUB]LNO[/SUB]/D[SUB]LCO[/SUB] ratio was increased in patients with moderate (n = 4, 11%) and severe COVID-19 (n = 23, 49%). Abnormal membrane conductance was also seen in all three groups of post-COVID-19 patients. These findings suggest a persistent alveolo-capillary gas transfer defect, implying not only reduced membrane conductance but also abnormal pulmonary vascular capacitance in all PACS patients, even those with a milder form of COVID-19 infection.
https://www.mdpi.com/2075-4426/14/7/738
https://doi.org/10.3390/jpm14070738
Hua-Huy, Thông, Hà Pham-Ngoc, Frédérique Aubourg, Christine Lorut, Nicolas Roche, and Anh Tuan Dinh-Xuan
Abstract
Impaired lung gas exchange is commonly seen in patients with pulmonary involvement related to SARS-CoV-2 acute infection or post-acute COVID-19 syndrome (PACS). The primary aim of our study was to assess lung gas transfer, measuring the pulmonary diffusion capacity for nitric oxide (D[SUB]LNO[/SUB]) and carbon monoxide (D[SUB]LCO[/SUB]) in all COVID-19 patients. Our secondary aim was to decipher the respective roles of perturbed lung membrane conductance (D[SUB]M[/SUB]) and reduced pulmonary capillary volume (V[SUB]C[/SUB]) in patients with impaired lung gas exchange. From May to October 2020, we measured D[SUB]LNO[/SUB]-D[SUB]LCO[/SUB] in 118 patients during their post-COVID-19 period (4.6 months after infection) to decipher alveolo-capillary gas transfer disturbances. D[SUB]LNO[/SUB]-D[SUB]LCO[/SUB] measurement was also performed in 28 healthy non-smokers as controls. Patients were classified into three groups according to the severity (mild, moderate, and severe) of acute COVID-19 infection. Patients with mild COVID-19 had normal lung volumes and airways expiratory flows but impaired pulmonary gas exchange, as shown by the significant decreases in D[SUB]LNO[/SUB], D[SUB]LCO[/SUB], D[SUB]M[/SUB], and V[SUB]C[/SUB] as compared with controls. V[SUB]C[/SUB] was significantly impaired and the D[SUB]LNO[/SUB]/D[SUB]LCO[/SUB] ratio was increased in patients with moderate (n = 4, 11%) and severe COVID-19 (n = 23, 49%). Abnormal membrane conductance was also seen in all three groups of post-COVID-19 patients. These findings suggest a persistent alveolo-capillary gas transfer defect, implying not only reduced membrane conductance but also abnormal pulmonary vascular capacitance in all PACS patients, even those with a milder form of COVID-19 infection.
https://www.mdpi.com/2075-4426/14/7/738