Abstract 11: Identifiable Patterns Of Noninvasive Cerebral Oximetry During Endovascular Therapy For Acute Ischemic Stroke Are Associated With Neurological Deterioration

Background: Cerebral near-infrared spectroscopy (NIRS) is a useful tool to monitor real-time cerebral oxygenation levels. However, the mechanisms through which varying oxygenation levels during endovascular thrombectomy (EVT) affect functional outcomes remain to be determined. In this study, we categorized NIRS trends into descriptive “fingerprints” and examined the relationship between these fingerprints and neurological worsening. Methods: We enrolled patients that presented to Yale New Haven Hospital with large vessel occlusion acute ischemic stroke and underwent EVT. NIRS was implemented into the standard operating procedure. Time stamps of defined events (medication administration, recanalization, etc.) were synchronized with corresponding NIRS values. We inspected NIRS curves from arrival to angio-suite to time of recanalization. Neurological deterioration was defined as an increase of 4 points or more on the National Institutes of Health Stroke Scale (NIHSS). Results: Forty-eight patients (mean age 72 ± 13, mean NIHSS 14) were analyzed. Five “fingerprints” were observed in the affected hemisphere: sustained decreases, downward rSO2 peaks, no change, upward rSO2 peaks, and sustained increases (Fig. 1), which were assigned nominal values of -2, -1, 0, 1, and 2, respectively. After adjusting for age and admission NIHSS, sustained decreases and downward rSO2 peaks were independently associated with neurological deterioration (P = 0.0076, Fig. 2). Conclusions: Identifiable NIRS “fingerprints” of downward rSO2 peaks and sustained decreases in the affected hemisphere during EVT are associated with neurological deterioration. Further distillation of identifiable intraprocedural NIRS trends in real time could provide guidance for anesthesia and hemodynamic management during EVT to optimize patient outcomes after stroke.