Clinical significance and impact on neurological outcomes of monitoring contralateral hemispheric oxygenation changes in intracranial mass surgeries

Basaran, R. Clinical Significance and Impact on Neurological Outcomes of Monitoring Contralateral Hemispheric Oxygenation Changes in Intracranial Mass Surgeries, Department of Anesthesiology and Reanimation, Faculty of Medicine, Eskişehir Osmangazi University, Eskişehir, 2025. In our study, we continuously monitored rSO2 values of both the tumor-bearing and non-tumor-bearing hemispheres in patients undergoing intracranial mass surgery, using non-invasive cerebral oximetry, compared to preoperative baseline values during the intraoperative and postoperative periods. This monitoring aimed to enable early detection of potential perioperative cerebral oxygenation disturbances, allowing for timely intervention and ultimately improving patients' neurological prognosis. Following ethical committee approval, 40 patients scheduled for surgery under general anesthesia were included in the study. Patients' demographic data were recorded preoperatively. Patients underwent standard monitoring, including regional oxygenation monitoring. The rSO2 values of each hemisphere, along with vital signs, were recorded preoperatively, post-induction, post-intubation, intraoperatively, and after surgery upon extubation and recovery. Statistical analysis revealed no significant difference in terms of patients' demographic data and comorbidities. Significant differences were found between baseline values and post-induction, post-intubation, and post-surgical values of vital signs and rSO2. The most important finding of our study was the greater increase in rSO2 in the hemisphere ipsilateral to the tumor location compared to the contralateral hemisphere after surgical intervention compared to pre-operative values. Our study demonstrated that perioperative cerebral oxygenation dynamics are complex and influenced by various factors in patients undergoing intracranial mass surgery. The clinical importance of rSO2 monitoring of the contralateral hemisphere, particularly in intracranial mass surgeries, was emphasized. It is believed that rSO2 monitoring could be a useful tool in guiding intraoperative and postoperative management strategies of surgical teams and preventing potential neurological complications.