Management of respiratory failure due to covid-19

The most concerning complication of SARS-CoV-2 infection (covid-19) is acute hypoxaemic respiratory failure requiring mechanical ventilation.Numerous mechanisms have been suggested for the substantial hypoxaemia seen in many patients. 1These include pulmonary oedema, haemoglobinopathies, vascular occlusion, and a mismatch between ventilation and perfusion.The available histopathology, however, shows diffuse alveolar damage 2 consistent with acute respiratory distress syndrome (ARDS).Several of the other suggested aetiologies are also consistent with ARDS, and microvascular and macrovascular thrombi in ARDS have been recognised for decades. 3The variable pulmonary compliance associated with severe covid-19 is comparable with pulmonary compliance values reported for ARDS. 4 5 The heterogeneity of ARDS is well documented, with distinct subtypes related to the degree of inflammation and response to positive end expiratory pressure (PEEP). 5 6Overall, the pathology seen in patients with covid-19 is very similar to established descriptions of ARDS.