Regional Cerebral Oxygen Saturation Monitoring during Spinal Surgery in Order to Identify Patients at Risk for Cerebral Desaturation

• Main Authors: Sniedze Murniece, Martin Soehle, Indulis Vanags, Biruta Mamaja
• Format: Article
• Language: English
• Published: MDPI AG 2020-03-01
• Series: Applied Sciences
• Subjects: cerebral oxygen saturation; near infrared spectroscopy; cerebral oximeter; spinal surgery
• Online Access: https://www.mdpi.com/2076-3417/10/6/2069

Background: Near infrared spectroscopy (NIRS) devices are non-invasive and monitor cerebral oxygen saturation (rScO₂) continuously. NIRS interventional protocol is available in order to avoid hypoxic brain injury. Methods: We recruited patients scheduled for spinal surgery (<i>n</i> = 44). rScO₂ was monitored throughout the surgery using INVOS 4100 cerebral oximeter. If the rScO₂ values dropped more than 20% below baseline, or there was an absolute drop to below 50%, NIRS interventional protocol was followed. Results: In two patients rScO₂ decreased by more than 20% from baseline values. In one patient rScO₂ decreased to below 50%. NIRS protocol was initiated. As the first step, correct head position was verified&#8722;in one patient rScO₂ increased above the threshold value. In the two remaining patients, mean arterial pressure was raised by injecting Ephedrin boluses as the next step. rScO₂ raised above threshold. Patients with desaturation episodes had longer medium time of the operation (114 &#177; 35 versus 200 &#177; 98 min, <i>p</i> = 0.01). Pearson&#8217;s correlation showed a negative correlation between rScO₂ and duration of operation (r = &#8722;0.9, <i>p</i> = 0.2). Receiver operating characteristic curve analysis showed blood loss to be a strong predictor for possible cerebral desaturation (Area under the curve (AUC): 0.947, 95%CI: 0.836&#8722;1.000, <i>p</i> = 0.04). Conclusion: Patients with higher blood loss might experience cerebral desaturation more often than spinal surgery patients without significant blood loss.