Cerebral microbleeds in acute respiratory distress syndrome

Abstract

Background: Cerebral microbleeds (CMB) have been observed in patients with critical illness. We sought to examine the frequency of CMB in patients with acute respiratory distress syndrome (ARDS) and association with neurologic complications including acute cerebral ischemia and seizures.

Methods: A retrospective review of patients with ARDS from January 2010 to October 2018 was performed. Patients with brain MRIs with susceptibility weighted imaging or gradient echo sequences were included. We compared neurologic complications and intensive care unit outcomes between patients with and without CMB. Cerebral small vessel disease (CSVD) was defined as the presence of CMB, lacunar infarcts, enlarged perivascular spaces, and white matter hyperintensities.

Results: Of 678 patients with ARDS, 61 met inclusion criteria. Median age was 54 years (IQR 42-63) and 28 were males. Of 12 (20%) with CMB, 10 had lobar CMB. Four patients had CMB in the corpus callosum, all involving the splenium. Neurologic complications were more common in those with CMB including acute cerebral ischemia (41.7% versus 10.2%, p=0.008) and seizures (33.3% versus 8.2%, p=0.021). ARDS rescue therapies were more commonly used in patients with CMB (p=0.005). There was no difference in hospital mortality (41.7% versus 34.7%, p=0.652). Patients with CMB did not have a higher CSVD score than those without CMB when accounting for the presence of CMB (median=1 versus 0, p=0.891).

Conclusion: CMB were present in twenty percent of patients with ARDS who had MRI and were more commonly seen in patients requiring ARDS rescue therapies.

Keywords: Acute respiratory distress syndrome; Cerebral microbleeds; Critical illness; Magnetic resonance imaging.