Radiology Rounds – 12/28/21

Today we’re bringing you a special edition of Radiology Rounds complete with classic imaging, and some key critical care and ventilator physiology. This case is a perfect lead-in for next week’s Pulm PEEPs Roundtable on PEEP titration, so make sure to tune in!

How would you best describe the imaging findings?


There are bilateral, diffuse alveolar infiltrates noted on imaging with evidence of an air bronchogram on the CT image.

The patient develops worsening hypoxemia requiring mechanical intubation. The patient has multifocal pneumonia and requires intubation. ABG is performed and the calculated PaO2:FIO2 ratio is 150. How would you describe the severity of ARDS?


This patient has moderate ARDS based on a PaO2:FIO2 ratio that is between 100 and 200. The patient’s initial ventilator settings on volume control are:

Based on these parameters, we can also calculate the driving pressure. Driving pressure is calculated by using Pplat-PEEP. In this case, Pplat (30)-PEEP (10), would give a driving pressure of 20.