Comparison of spinal and cerebral oxygen saturation with near-infrared spectroscopy method during spinal surgery in prone position

Objectives: To assess spinal and cerebral oxygenation with near-infrared spectroscopy method during spinal surgery in prone position. Methods: This prospective study included 64 patients, who were prepared for posterior spinal instrumentation and laminectomy surgeries. Group 1: 31 patients who had posterior spinal instrumentation; Group 2: 33 patients who had at least two levels of disk operation (Laminectomy). The following were recorded for all patients before and after anesthesia induction in supine position, after induction in prone position, during operation (beginning, middle and end of surgery) in prone position and before waking up in supine position: cerebral oxygen saturation (NIRSs) measurements, spinal oxygen saturation (NIRSp) measurements, peripheral oxygen saturation (SpO 2 ), heart rate (HR), invasively monitored systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) values. Results: There was no significant difference between two groups in terms of the variables of age, weight, anesthesia and surgery duration ( p > 0.05). MAP values were significantly different in both groups before induction, during operation and postoperative periods ( p 0.05). We found no significant difference between groups in HR, SAP, DAP, MAP, NIRSs and NIRSp parameters ( p > 0.05) compared at different times. Conclusions: MAP dropped depending on induction and prone position. Cerebral oxygenation significantly decreased at the time of mid-operation and at the end of operation but spinal oxygenation had no significant decresase. Compared to laminectomy, posterior stabilization surgery did not pose an additional risk to the patients in terms of spinal and oxygen saturation.