Structural Brain Injury on Brain Magnetic Resonance Imaging in Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is an acute inflammatory respiratory failure condition that may be associated with brain injury. We aimed to describe the types of structural brain injuries detected by brain magnetic resonance imaging (MRI) among patients with ARDS.

We retrospectively reviewed and collected data on brain injuries as detected by brain MRI during index hospitalization of all patients with ARDS at a single tertiary center in the United States from January 2010 to October 2018 (pre-COVID era). Structural brain injuries were classified as cerebral ischemia (ischemic infarct and hypoxic-ischemic brain injury) or cerebral hemorrhage (intraparenchymal hemorrhage, cerebral microbleeds, subarachnoid hemorrhage, and subdural hematoma). Descriptive statistics were conducted.

Of the 678 patients with ARDS, 66 (9.7%) underwent brain MRI during their ARDS illness. The most common indication for brain MRI was encephalopathy (45.4%), and the median time from hospital admission to MRI was 10 days (interquartile range 4-17). Of 66 patients, 29 (44%) had MRI evidence of brain injury, including cerebral ischemia in 33% (22 of 66) and cerebral hemorrhage in 21% (14 of 66). Among those with cerebral ischemia, common findings were bilateral globus pallidus infarcts (n = 7, 32%), multifocal infarcts (n = 5, 23%), and diffuse hypoxic-ischemic brain injury (n = 3, 14%). Of those with cerebral hemorrhage, common findings were cerebral microbleeds (n = 12, 86%) and intraparenchymal hemorrhage (n = 2, 14%). Patients with ARDS with cerebral hemorrhage had significantly greater use of rescue therapies, including prone positioning (28.6% vs. 5.8%, p = 0.03), inhaled vasodilator (35.7% vs. 11.5%, p = 0.046), and recruitment maneuver (14.3% vs. 0%, p = 0.04).

Structural brain injury was not uncommon among selected patients with ARDS who underwent brain MRI. The majority of brain injuries seen were bilateral globus pallidus infarcts and cerebral microbleeds.