Intraoperative microrecording under general anaesthesia with bispectral analysis monitoring in a case of deep brain stimulation surgery for Parkinson’s disease

Abstract

Sirs, Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is currently the most common therapeutic surgical procedure for patients with advanced ParkinsonÕs disease (PD) and motor complications, not controlled by the pharmacological treatment. The success of the post-operative clinical outcome depends on careful patient selection and an optimal targeting of the STN. To improve the location accuracy of this nucleus, intraoperative microrecordings are performed in most centres. The standard procedure of electrodes implantation is usually carried out under local anaesthesia [1]. Experience in intraoperative microrecording of STN under general anaesthesia is scarce [2], and neuronal firing patterns are not well typified.We describe the intraoperative microrecording results obtained from a patient with advanced PD who underwent implantation of DBS electrodes in the STN under general anaesthesia using Bispectral Analysis of the Electroencephalogram (BIS). This technique allows hypnotic titration over the complete range of cortical activity. A BIS value of 65-85 is recommended for sedation and 40-65 for general anaesthesia [3]. BIS values correspond linearly to the hypnotic dose of intravenous or volatile agents [4] and, therefore, it allows changing the level of sedation and analgesia rapidly to accommodate specific requirements such as intraoperative microrecording.A 59-year-old man with a 7-year history of PD complicated with motor fluctuations and dyskinesias was scheduled for DBS of STN. General anaesthesia was used during the surgical procedure because the patient experienced a severe painful cervical dystonia which prevented positioning the stereotactic frame.Propofol 200 mg, fentanyl 150 lg and cisatracurium 10 mg were administered, then target propofol and remifentanyl concentrations were adjusted to achieve a BIS value of 60-65 during microrecordings, the lightest level of a general anaesthesia.

Influence of Propofol and Fentanyl on Deep Brain Stimulation of the Subthalamic Nucleus

“…Propofol has been widely used alone or combined with remifentanyl. The mean infusion rate of propofol reported in the literature is approximately 50 µg/kg/min (15, 16). The use of propofol alleviates intraoperative patients' discomfort to make the operating time shorter and frees the patients from a bad memory of the painful procedure of bilateral STN DBS.…”

“…The monitoring of the depth of anesthesia to titrate sedation and the state of arousal during DBS insertion would be ideal. The Bispectral index (BIS) is used to monitor the depth of anesthesia (16, 29, 30). A BIS value of 65-85 is recommended for sedation and 40-65 for general anesthesia.…”

Subthalamic Deep Brain Stimulation in Parkinson’s Disease under Different Anesthetic Modalities: A Comparative Cohort Study

“…The use of intravenous propofol and remifentanil as general anesthetic agents during STN-DBS was reported in many papers. MER was performed properly without affecting the surgical outcome only when remifentanil dosing was stopped and the dose of propofol was carefully monitored [7,8,21] . It was reported by Hertel et al [7] that the mean firing rate of STN neurons in patients who received intravenous propofol anesthetic was 40 Hz (25-50 Hz).…”

Deep Brain Stimulation—Surgery for Movement Disorders and Parkinson's Disease

“…General anesthesia with higher doses of remifentanil and propofol has been used. 25,26 The STN and the typical bursting pattern could be identified but a widening of the baseline noise could not. 25 Bispectral analysis monitoring was used.…”