gms | German Medical Science

Objective: The widely used asleep-awake-asleep protocol (SASP) in awake craniotomies makes reliable intraoperative testing difficult since patients are frequently disoriented when woken-up from sedation. Furthermore, this protocol carries anaesthesiological risks with respiratory complications being the most common. To eliminate potential risks for the patient during awake craniotomies and in order to improve reliability of intraoperative test results we implemented a new protocol for awake craniotomies, called awake-awake protocol (AAP). Contrary to the SASP the patient is awake during the entire procedure and no sedatives are used. We present the results of the first 50 cases with this new protocol.

Methods: We retrospectively analyzed awake-awake craniotomies at our centre between 11/2006 and 10/2011. Data included OR-records, imaging, anesthesiological protocols and patient’s charts. Intraoperative neuropsychological data were additionally compared with immediate postoperative tests (finger tapping, MWT-B-test, DO40, Wordfluency Test) of 38 non-neurosurgical patients who had regional anaesthesia with sedation (RAS) or total intravenous anaesthesia (TIVA).

Results: Data of 50 consecutive awake craniotomies of 48 patients (30 m / 18 f) with a mean age of 45 years were analyzed. Tumors consisted of 21 GBMs, 16 °III and 9 °II gliomas, 3 mets and 1 cavernoma. A gross total resection (> 90%) was achieved in 74%. One patient (2%) had a new major neurological deficit (Hemiplegia) post-operatively and seven patients (14%) suffered from an aggravation of preoperative deficits. One patient had a generalized seizure and had to be intubated. Seven patients (14%) with intraoperative seizures triggered by direct cortical stimulation could be limited with ice water. Beside one deep wound infection there were no anesthesiological or surgical complications in this study. Stress levels, defined by blood pressure and heart rate changes, were significantly lower throughout the procedure than while the intraoperative testing. The neuropsychological tests in patients without any sedation showed significant better results compared to RAS and TIVA regimen.

Conclusions: The introduced awake-awake protocol is a reliable and well tolerated procedure. Stress levels during the whole procedure remained low. With this method, sedation related respiratory and hemodynamic complications can be avoided. Furthermore intraoperative neuropsychological and motor test results become more reliable, which gives rise to safer surgery.