Research Of Anesthesia For Awake Craniotomy And Consciousness Level

Objective To discuss the necessary level of consciousness for resection of tumors in eloquent cortex under wake-up during general anesthesia.Methods To select 9 cases who had lesions in eloquent cortex and been operated elective surgery. The anxiety statuses of the patients were evaluated consulting the Self-Rating Anxiety Scale(SAS) at the day before the operations. Scalp incision ropivacaine local infiltrating anesthesia was used and ventilation by PLMA. Target controlled infusion of propofol plus remifentanil compounding sufentanil intravenous injection. The SPB,DBP,MAP,HR,SpO₂ and BIS at each time points were monitored during the operations. Motor function and language function were monitored (by hand and foot action,pictures identifying and continuous number counting) after wake-up during the operation. And to proceed Observer's Assessment of Alertness/Sedation Scale(OAA/S) and Visual Analogue Scale(VAS) after wake-up. Their levels of consciousness were assessed referencing positioning state criteria of functional region. To record the wake-up time (between the time of medicine stopping and the time of open eyes), and then locate by neural-electrophysiological to confirm linguistic area and their scope. There were 3 months'postoperative follow-up.Results (1) 8 cases were successfully inserted through the general anesthesia wake-up and then the process of general anesthesia with intraoperative hemodynamic stability and unobstructed airway. It fulfilled the patients'request to monitor the language function and locate language area by neural-electrophysiological monitoring. We gave up to keeping on wake-up the other 1 patient because epilepsy sustained attacked during the operation after wake-up. The lesions of the 8 patients'were resected completely and subtotal lesion of the other 1 was resected. (2) The 8 patients whose SAS before they received anesthesia,OAA/S and VAS after wake-up were normal. The other 1 whose SAS before they received anesthesia was 62, mild anxiety. The OAA/S was 2.5 and VAS was 8.0 after wake-up. We gave up to keeping on wake-up by intravenous injection of propofol immediately because epilepsy sustained attacked and elevated intracranial pressure and the brain tissue bulging during the operation after wake-up. (3) Surgical status was excellent in 7 cases, good in 1, and poor in 1. 8 patients had clear speech in awake state, 8 had the ability to accurately response to instruction, 8 felt no pain and 8 had normal intracranial pressure. 1 had the sustained development of epilepsy because of brain swelling. The wake-up time was (15.6±2.5) min. (4) All 9 patients didn't appear new neurological dysfunction and took an obvious and favorable turn than preoperation during the 3 months'follow-up visit. 8 patients'function turned back to normal and 1 had mild language dysfunction. All 9 patients had no bad memory about operation in awake state.Conclusion Wake-up anesthesia in functional region with scalp incision ropivacaine local infiltrating anesthesia with target controlled infusion of propofol plus remifentanil compounding sufentanil by PLMA ventilation can provide satisfactory depth of anesthesia in patients and meet the requirements of intraoperative wake-up.