Deep brain stimulation and general anesthesia

Aim of the Study: To study the effect of general anesthesia during electrode placement on the clinical outcome of Deep brain stimulation of the subthalamic nucleus (DBS-STN). Introduction: DBS-STN is an effective therapy in patients with advanced Parkinson's disease. Both, activity of subcortical neurons and intraoperative clinical testing important to control exact electrode placement are potentially obscured by analgesic or sedative drugs that are often necessary to reduce the patient's discomfort and to provide optimal surgical conditions. Materials and Methods: We retrospectively analyzed 47 consecutive patients who underwent DBS-STN. 7 patients did not receive any systemic anesthetic while 40 patients were given sedatives and/or analgesics (propofol alone: n = 13, propofol and remifentanyl: n = 9, propofol and alfentanil n = 1, remifentanil alone: n = 13, alfentanil and midazolam n = 4). Results: There were no significant differences between the 5 groups of patients in respect to improvement of Parkinsonian symptoms measured by the Unified Parkinson's Disease Rating Scale part III (UPDRS III) or the reduction of antiparkinsonian medication analyzed as levodopa equivalent units (LEU). However, analyses of pooled data from all patients treated with propofol (n = 23) showed less stimulation induced improvement of motor symptoms (UPDRS part III 32 +/- 6%) and a reduction of antiparkinsonian medication (LEU 55 +/- 4%) compared to patients who did not receive propofol (UPDRS III, 50 +/- 3%, p < 0.05; LEU 66 +/- 2%, p < 0.05). Surprisingly, no effect was detected in respect to analgesics when a similar approach was applied. Discussion/Conclusions: These preliminary data could indicate that propofol should be used with some caution during electrode placement of DBS-STN and a potential adverse effect should be addressed in an appropriate prospective trial. (C) 2011 Elsevier GmbH. All rights reserved.