Continuous Monitoring of Cerebral Near-Infrared Spectroscope (NIRS) after Cerebral Air Embolism

An elderly woman suddenly had a right side cerebral air embolism (CAE) with seizures and unconsciousness during bronchoscopic biopsies, so was transferred to our hospital. Magnetic resonance imaging (MRI) showed no acute ischemic changes two hours after CAE in both hemispheres. Despite no active MRI findings, near-infrared spectroscope (NIRS), started soon after the MRI, showed lower regional oxygen saturations (rSO2) in the right side as compared to the unaffected side. These changes lasted for about two days, which suggested cerebral blood flow alterations in the CAE side. Three days later, she regained consciousness but had paresis of the left upper limb. Thus, we might need to pay attention to changes in rSO2 using continuous monitoring of NIRS after CAE.