Multimodal Regional Brain Monitoring of Tissue Ischemia in Severe Cerebral Venous Sinus Thrombosis.

Abstract

Comatose critically ill patients with severe diffuse cerebral venous thrombosis (CVT) are at high risk of secondary hypoxic/ischemic insults, which may considerably worsen neurological recovery. Multimodal brain monitoring (MBM) may therefore improve patient care in this setting, yet no data are available in the literature. We report two patients with coma following severe diffuseCVT who underwent emergent invasive MBM with intracranial pressure (ICP), brain tissue oximetry (PbtO2), and cerebral microdialysis (CMD). Therapy of CVT consisted of intravenous unfractionated heparin (UFH), followed by endovascular mechanical thrombectomy (EMT). EMT efficacy was assessed continuously at the bedside using MBM. Despite effective therapeutic UFH (aPTT two times baseline levels in the two subjects), average CMD levels of lactate and glucose in the 6h prior to EMT displayed evidence of regional brain ischemia. The EMT procedure was associated with a rapid (within 6h) improvement in both CMD lactate (6.42 ± 0.61 4.89 ± 0.55mmol/L, p = 0.02) and glucose (0.49 ± 0.17 vs. 0.96 ± 0.32mmol/L, p = 0.0005). EMT was also associated with a significant increase in PbtO2 (22.9 ± 7.5 vs. 30.1 ± 3.6mmHg, p = 0.0003) and a decrease in CMD glutamate (12.69 ± 1.06 vs. 5.73 ± 1.76μmol/L, p = 0.017) and intracranial pressure (ICP) (13 ± 4 vs. 11 ± 4mmHg (p = 004). Patients did not require surgical decompression, regained consciousness, and were discharged from the hospital with a good neurological outcome (modified Rankin score 3 and 4). This study illustrates the potential utility of continuous bedside MBM in patients with coma after severe brain injury, irrespective of the primary acute cerebral condition. Despite adequate ICP and PbtO2 control, the presence of CMD signs of regional brain cell ischemia triggered emergent EMT to treat CVT, which was associated with a significant and clinically relevant improvement of intracerebral physiology.