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Proper Airway Maintenance Improves Perioperative Safety for Deep Brain Stimulation
- Michael G Irwin (4 November 2009)
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Proper Airway Maintenance Improves Perioperative Safety for Deep Brain Stimulation
- Chi-Tsung Chien, Chia-Wen Chen, Department of Anaesthesia, Pain Service, and Critical Care Medicine, China Medical University Hospital, Taiwan (3 November 2009)
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Anaesthesia for deep brain stimulation
- Michael G Irwin (3 November 2009)
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Anaesthesia for deep brain stimulation
- Ian Thomas, Judith Dunnet, Shazia Javed, Steven Gill (26 October 2009)
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Michael G Irwin
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We thank Dr Chien for this additional information. We have tried to highlight the importance of appropriate sedative and analgesic drug selection in our review and welcome further comments on personal experience in this regard. Conflict of Interest:None declared |
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Chi-Tsung Chien Department of Anesthesiology, Cathay General Hospital Sijhih, Taiwan, Chia-Wen Chen, Department of Anaesthesia, Pain Service, and Critical Care Medicine, China Medical University Hospital, Taiwan
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To the Editor Deep brain stimulation (DBS) is increasingly accepted in the treatment of Parkinson’s disease (PD) and other movement disorder. As the excellent review by Poon and Irwin mentioned, anesthesiologists meet the dilemma between patients’ comfort and optimal surgical conditions, including intraoperative neuromonitoring. Local anaesthesia or an “awake” monitored anaesthesia with or without light sedation is the most common method for patients undergoing deep brain stimulation(1). However, more concern should be taken with respect to respiratory complications in all anesthetic techniques, even the rate of perioperative risks is around 1.6%. Patients’ weaker cardiopulmonary reserve may arise not only from old age and co-morbidities, but also from PD which, itself alone, might cause patients’ pulmonary function impairment(2). The fixed stereotactic headframe could also make access to the patient’s airway difficult, or even impossible. Although local anaesthesia is widely used, it is still suffering because (i) the procedures tend to be long in duration and (ii) patients are unable to alter their position once the procedure is underway, which increases patients’ level of anxiety or restlessness(1). In addition, tremors, agitation, seizures, and even fatigue, might influence hemodynamic stability and increase the risk of perioperative complications, including intracranial hemorrhage as well as cardiovascular events. The patients’ body might also shift, causing difficulty in breathing or even complete airway obstruction(3). In our experience, we usually choose monitored anaesthesia with light sedation only during the period of nonintervention, which provide more comfort and safety for our patient as well as minimize the disturbance of neuromonitoring as almost all analytic drugs might have adverse effects on neurophysiologic monitoring(4). Infusion of alfentanil (0.3- 0.5μg/kg/hr) and dexmedetomidine (0.3-0.5μg/kg/hr), as well as intermittently intravenous bolus of propofol 10-20 mg for sedation, is used during interventional procedures. But preoperatively nasal endotracheal intubation is prepared while the patient is awake. To further reduce the stimulation of the endotracheal tube, 2 ml of 2% lidocaine is infiltrated around the endotracheal tube cuff intermittently via the epidural catheter tip positioned over the surface of the cuff. The patients are spontaneously breathing in FiO2 50%, and gentle assisted manual ventilation is only given to maintain adequate tidal volume. Patients could well tolerate the endotracheal tube while being awake and cooperative during the periods of nonintervention and neuromonitoring with suspending intravenous medications. The operation can be smoothly completed even in a four-hour operation without any sneezing or coughing. Hemodynamics is stable and neither hypoxemia nor hypercarbia is noted. This application is similar to the technique used by Huncke and co- workers(5). Intratracheal local anesthetics infiltration reduces the discomfort and stimulation of endotracheal tube, while also inhibit cough reflex through the complete course. It decreases the risks of respiratory suppression by sedatives, which might cause hypoxemia or hypercapnia, both in turn result in increasing intracranial pressure and neurological complications(6). End-tidal carbon dioxide could be monitored for detecting venous air embolism. Modifications using extraglottic airway devices (EGA) such as laryngeal masks are also widely used(7), but endotracheal intubation still provides more securing ventilation without needs for emergent airway management as malposition of these devices is a major concern. In addition, the late stages of PD present high incidence of aspiration pneumonia(2). In these cases, endotracheal tube provides better manual assisted ventilation than EGA for blood gases control with decreased risk of gastric inflation and aspiration(8). At present, there are still no studies comparing different anesthetic techniques and perioperative risks for DBS procedures. The balance between patient’s comfort and surgical consideration for anesthesiologists is challenging and, thus, might be also considered case by case. In our opinion, a good ventilation support as we use provides benefits for reducing not only respiratory but also possible neurological complications, especially in patients with more severe condition. Further risk-to-benefit assessment needs more prospective studies. References 1.Poon CC, Irwin MG. Anaesthesia for deep brain stimulation and in patients with implanted neurostimulator devices. Br J Anaesth 2009; 103: 152-65 2.Mikaeele H, Arami M, Marandi M, Ansarin K. Respiratory Problems in Parkinson Disease. Clinical Pulmonary Medicine 2009; 16: 139 3.Venkatraghavan L, Manninen P, Mak P, Lukitto K, Hodaie M, Lozano A. Anaesthesia for functional neurosurgery: review of complications. J Neurosurg Anesthesiol 2006; 18: 64-7 4.Khatib R, Ebrahim Z, Rezai A, et al. Perioperative events during deep brain stimulation: the experience at cleveland clinic. J Neurosurg Anesthesiol 2008; 20: 36-40 5.Huncke K, Van de Wiele B, Fried I, Rubinstein EH. The asleep-awake- asleep anesthetic technique for intraoperative language mapping. Neurosurgery 1998; 42: 1312-6; discussion 6-7 6.Bilotta F, Rosa G. 'Anaesthesia' for awake neurosurgery. Curr Opin Anaesthesiol 2009; 22: 560-5 7.Deiner S, Hagen J. Parkinson's disease and deep brain stimulator placement. Anesthesiol Clin 2009; 27: 391-415, table of contents 8.Asai T. Editorial II: Who is at increased risk of pulmonary aspiration? Br J Anaesth 2004; 93: 497-500 Conflict of Interest:None declared |
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Michael G Irwin, Professor University of Hong Kong
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Thank you for sharing your surgical technique for DBS. Surgical innovation in this area, such as you have described, that avoids exposing patients to long hours of awake surgery is certainly welcome. Your article in the journal Neurosurgery focuses on the surgical technique with no details of anaesthesia apart from stating that it was general anaesthesia [1]. Expert commentary in the same issue of the journal, however, suggests that other neurosurgeons, while generally positive, are “unconvinced that it is a better way” and “do not trust MRI localization without physiological control“. An anaesthesia journal is obviously not an appropriate forum for debate on the relative merits of surgical techniques and we, therefore, have confined our review accordingly [2]. It is apparent that there is still a demand for “awake” techniques and we feel our review has adequately addressed these. References 1. Patel NK, Plaha P, Gill SS. Magnetic resonance imaging directed method for functional neurosurgery using implantable guide tubes. Neurosurgery 2007 Nov; 61 (5 suppl 2): 358-65. 2. Poon CCM and Irwin MG. Anaesthesia for deep brain stimulation and in patients with neurostimulator devices. Br J Anaesth 2009; 103: 152-65. Conflict of Interest:I am an author of the review article referred to |
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Ian Thomas , Judith Dunnet, Shazia Javed, Steven Gill
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Editor – We read with interest the article by Poon and Irwin(1) reviewing anaesthetic techniques for patients undergoing deep brain stimulation (DBS) electrode placement. Since 2001 our unit has completed 251 deep brain stimulation cases carried out entirely under general anaesthetia with 507 electrodes inserted using a technique that employs implantable guide tubes (Electrode Introducer Kit, Renishaw PLC, United Kingdom) to facilitate peri-operative magnetic resonance imaging (MRI) confirmation of electrode placement. Our method and procedural complication rates were published in 2007(2) and with ongoing internal audit our complication rates for all 251 patients are shown in table 1. Other authors report similar complication rates using various implantation techniques carried out under general anaesthesia albeit with smaller numbers of patients(3,4). We believe our complication rate compares favourably with the data quoted by Poon and Irwin with the advantage that a general anaesthetic technique eliminates the physical pain and psychological suffering that almost all patients who underwent DBS electrode insertion whilst ‘awake’(5) were able to recall. We also allow patients to take their normal anti-parkinson medication prior to surgery so avoiding the unpleasant dystonia or pain that they may experience as a result of withholding medication to optimise assessment(1). Using general anaesthesia as opposed to an ‘awake’ technique does mean that intra-operative assessment of motor disability and dyskinesia is impossible but we do not believe that this has a significant impact on clinical results. Outcome data for patients who have undergone deep brain stimulation under general anaesthesia at our centre are comparable to other centres and in some specific areas e.g. tremor, are superior(6,7,8). Therefore, to alleviate pain or psychological distress that ‘awake’ patients having DBS electrode placement may experience and whilst our complication rates and clinical outcomes compare favourably to other centres, general anaesthesia will continue to be our technique of choice. Table 1: Rates of complications in 251 patients undergoing functional neurosurgery under general anaesthesia Complication, Incidence (%) Device related/surgical site infection, 6 (2.4%) Post operative confusion (transient), 3 (1.2%) Pulmonary embolus (1 patient death as a result), 3 (1.2%) Seizure (both single episode of complex partial seizure), 2 (0.8%) Pneumonia, 1 (0.4%) Haematoma at battery site (on re-warfarinising patient with mechanical heart valve), 1 (0.4%) Neurological deficit (non-haemorrhagic paresis), 1 (0.4%) Revisional surgery (due to incorrect guide tube length measurement), 1 (0.4%) Intra-cranial haemorrhage, 1 (0.4%) References: 1.Poon CCM and Irwin MG. Anaesthesia for deep brain stimulation and in patients with neurostimulator devices. Br J Anaesth 2009; 103: 152-65. 2.Patel NK, Plaha P, Gill SS. Magnetic resonance imaging directed method for functional neurosurgery using implantable guide tubes. Neurosurgery 2007 Nov; 61 (5 suppl 2): 358-65. 3.Coubes P, Vayssiere N, El Fertit H et al. Sterotact Funct Neurosurg 2002; 78 (3-4): 183-91. 4.Starr PA, Martin AJ, Ostrem JL et al. Subthalamic nucleus deep brain stimulator placement using high field interventional magnetic resonance imaging and a skull-mounted aiming device: technique and application accuracy. J Neurosurg 2009; published on line August 14, 2009; DOI: 10.3171/2009.6.JNS081161 5.Chevrier E, Fraix V, Krack P et al. Is there a role for physiotherapy during deep brain stimulation surgery in patients with Parkinson’s disease? Eur J Neurol 2006; 13:496-8. 6.Plaha P, Khan S, Gill SS. Bilateral stimulation of the caudal zone incerta nucleus for tremor control. J Neurol Neurosurg Psychiatry 2008 May; 79 (5): 504-13. 7.Plaha P, Ben-Shlomo Y, Patel NK et al. Stimulation of the caudal zone incerta is superior to stimulation of the subthalamic nucleus in improving contra-lateral parkinsonism. Brain 2006 Jul; 129 (7):1732-47. 8.Plaha P, Gill SS. Bilateral deep brain stimulation of the pedunculopontine nucleus for Parkinson’s disease. Neuroreport 2005 Nov 28; 16(17): 1883-7. Conflict of Interest:None declared |
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