Carotid artery stenosis constitutes a major risk factor for ischemic stroke so carotid endarterectomy is performed to protects patients with severe atherosclerotic carotid artery stenosis against stroke.~Surgical Pleth Index (SPI) is reported to properly reflect nociception-antinociception balance in patients undergoing surgical procedures, where a value of 100 corresponds to a high stress level and a value of 0 to a low stress level; values near 50 or increase in value > delta 10 correspond to the stress level which is known to reflect requirement for rescue analgesia.~A randomized interventional trial to evaluate the effects of SPI-guided rescue analgesia on hemodynamic stability during anesthesia in patients undergoing carotid endarterectomy under cervical plexus block.
The aim of this randomized prospective trial is to assess the utility of Adequacy of Anaesthesia technique (Response Entropy and Surgical Pleth Index) for monitoring pain perception intraoperatively, maintainance of hemodynamic stability during anesthesia and its influence on postoperative outcomes, in patients undergoing carotid endarterectomy under cervical plexus block.