Regional variations in brain oxygenation during temporary clipping in aneurysm surgery

Objectives: Brain tissue oxygen concentration (PbtO2) monitoring has been used in aneurysm surgery to detect decreased brain oxygenation during temporary clipping. The effects of circulatory interruption according to different aneurysm locations have not been established. In this work, variations in PbtO2 during temporary clipping were studied in anterior communicating (AcomA), posterior communicating (PcomA) origin, and middle cerebral artery (MCA) aneurysm surgery.Methods: PbtO2 was monitored during surgery of 41 patients; aneurysms were located in the AcomA (10 cases), origin of PcomA (8 cases), and MCA bifurcation (23 cases). Temporary clips were used in all cases. Variations in PbtO2 values obtained during application of temporary clips were evaluated and studied according to the duration and type of circulatory interruption for each aneurysm location.Results: In AcomA aneurysm surgery, a significant decrease in PbtO2 values was found in 31% of the periods of temporary clipping, whereas in Pc...