Invasive Pleural Manometry to Explore the Physiology Behind Paradoxical Compliance Response to Abdominal Compression-A Case of "Unexpandable" Lung in Acute Respiratory Distress Syndrome.

Background: Recent reports have described an intriguing pathophysiological phenomenon in acute respiratory distress syndrome (ARDS), with the paradoxical improvement of respiratory mechanics after maneuvers raising intra-abdominal pressure in the context of low positive end-expiratory pressure.

Case summary: We hereby present a case exhibiting this paradoxical physiology during mechanical ventilation for severe COVID-19-associated ARDS and discuss the findings of our physiologic assessment of this condition with invasive pleural manometry performed at the bedside.

Conclusions: Even though it is rare, awareness of this intriguing condition is paramount to the critical care physician as the lung mechanics of these patients can deteriorate with traditional treatment strategies.