Anesthesia For Neurosurgery Research Articles

Intrarectal Anesthesia in Neurosurgery.

In the early days of modern neurologic surgery, the inconveniences and potential dangers of general anesthesia by chloroform and ether using the so-called "open-drop technique" led to the quest for alternative methods of anesthesia. This became all the more necessary, since patient positioning and the surgical arrangements often hindered the use of a drop bottle. One approach to solve this problem was intrarectal ether application. The present article aims to shed light on this original, less well-known anesthesia technique in the neurosurgical field.

Respiratory variation in peak aortic velocity accurately predicts fluid responsiveness in children undergoing neurosurgery under general anesthesia.

The determination of fluid responsiveness in the critically ill child is of vital importance, more so as fluid overload becomes increasingly associated with worse outcomes. Dynamic markers of volume responsiveness have shown some promise in the pediatric population, but more research is needed before they can be adopted for widespread use. Our aim was to investigate effectiveness of respiratory variation in peak aortic velocity and pulse pressure variation to predict fluid responsiveness, and determine their optimal cutoff values. We performed aprospective, observational study at a single tertiary care pediatric center. Twenty-one children with normal cardiorespiratory status undergoing general anesthesia for neurosurgery were enrolled. Respiratory variation in peak aortic velocity (ΔVpeak ao) was measured both before and after volume expansion using a bedside ultrasound device. Pulse pressure variation (PPV) value was obtained from the bedside monitor. All patients received a 10ml/kg fluid bolus as volume expansion, and were qualified as responders if stroke volume increased >15% as a result. Utility of ΔVpeak ao and PPV and to predict responsiveness to volume expansion was investigated. A baseline ΔVpeak ao value of greater than or equal to 12.3% best predicted a positive response to volume expansion, with a sensitivity of 77%, specificity of 89% and area under receiver operating characteristic curve of 0.90. PPV failed to demonstrate utility in this patient population. Respiratory variation in peak aortic velocity is a promising marker for optimization of perioperative fluid therapy in the pediatric population and can be accurately measured using bedside ultrasonography. More research is needed to evaluate the lack of effectiveness of pulse pressure variation for this purpose.

Desflurane in neurosurgery: Pros

AbstractNeurosurgery and neuroanaesthesia are making rapid progress, and with this progress, there is the search for excellence and ideal results. The practice of neuroanaesthesia is fairly standardised today, and any debate can only be on the fine-tuning aspects of the techniques. The aim of all research in anaesthesia is to provide the best possible and safest operating conditions and to have a complete recovery at the end of the surgery. The maintenance of anaesthesia for neurosurgery is with balanced general anaesthesia which combines intravenous and inhalational agents. A review of literature shows that desflurane has definite advantages, and hence, it is an integral part of modern neuroanaesthesia.

Clinical Anesthesia Fundamentals

Clinical Anesthesia Fundamentals

The evolution of brain surgery on awake patients.

In the early days of modern neurological surgery, the inconveniences and potential dangers of general anesthesia by chloroform and ether using the so-called "open-drop technique" led to the quest for alternative methods of anesthesia. Besides preventing the feared side effects, the introduction of regional anesthesia revealed another decisive advantage over general anesthesia in neurosurgery: While intraoperative direct cortical stimulation under general anesthesia could only delineate the motor area (by evocation of contralateral muscular contraction), now, the awake patients were able to report sensations elicited by this method. These properties advanced regional anesthesia to the regimen of choice for cranial surgeries in the first half of the 20th century. While technical advances and new drugs led to a progressive return to general anesthesia for neurosurgical procedures, the use of regional anesthesia for epilepsy surgery has only decreased in recent decades. Meanwhile, awake craniotomies regained popularity in oncologically motivated surgeries, especially in craniotomies for diffuse low-grade gliomas. Intraoperative mapping of brain functions using electrical stimulation in awake patients enables not only for increased tumor removal while preserving the functional status of the patients but also opens a window to cognitive neuroscience. Observations during such interventions and their correlation with both pre - and postoperative neuropsychological examinations and functional neuroimaging is progressively leading to new insights into the complex functional anatomy of the human brain. Furthermore, it broadens our knowledge on cerebral network reorganization in the presence of disease-with implications for all disciplines of clinical neuroscience.

Bis Monitoring during Intraoperative Neuromonitoring for Neurosurgery or How to Avoid Anesthesia Awareness due to Unusual Circumstances

Introduction: Incidence of anesthesia awareness persist - 0.2% to 40% of patients undergoing different kind of surgery.The Intraoperative Neuromonitoring for Neurosurgery sets an unusual low limits for upper doses of the different medications, used for general anesthesia maintenance. Thus provides a higher risk for anesthesia awareness incidence and the use of BIS Index is mandаtory. Aim: Patients undergoing general anesthesia for intraoperative neuromonitoring for posterior fossa neurosurgery.The first goal was to maintenance BIS Index between 40 and 60 point as is required. For safety, the target point was 40 points of BIS Index. Our goals are to put on discussion the BIS Index range for safe general anesthesia for IONM due to neurosurgery and also to purpose another safety range. Material and Methods: Eleven ASA II - ASA III patients undergoing tumor fossa posterior neurosurgery with direct nerve stimulation IONM were observed prospectively. General anesthesia appropriate for direct nerve stimulation IONM was made. Dräger Primus Anaethesia Workstation attached to Dräger Infinity Kappa patient monitor with BISx™ SmartPod was used for maintenance and monitoring general anesthesia with BIS Index. Results: In different stages of the general anesthesia for neurosurgery with IONM for tumor fossa posterior we observe BIS Index between 27 and 64 BIS points. Conclusion: Based on the facts, our observations and recently published paper for anesthesia awareness we think that the bottom level of 40 points BIS Index for general anesthesia is not always safety. That’s way we recommend revision of and BIS Index bottom line decreasing at level 30 points.

BiSpectral Index (BIS) monitoring may detect critical hypotension before automated non-invasive blood pressure (NIBP) measurement during general anaesthesia; a case report.

A patient undergoing general anaesthesia for neurosurgery exhibited an unexpected sudden decrease in the BiSpectral Index (BIS) value to near-zero. This prompted the detection of profound hypotension using non-invasive blood pressure (NIBP) measurement and expedited urgent assessment and treatment, with the patient making a full recovery. Widely regarded as a ‘depth of anaesthesia’ monitor, this case demonstrates the potential extra clinical benefit BIS may have in the detection of critical incidents such as anaphylaxis during general anaesthesia.

Development and clinical use of dexmedetomidine in neurosurgical procedures

Background Dexmedetomidine (DEX) is a potent and highly selective α-2 adrenoreceptor agonist,it provides dose-dependent sedation,analgesia,anxiolysis and sympatholysis.It doesn't increase intracranial pressure and can provide good pereoperative homodynamic stability with decreased intraoperative anesthetics requirements,especial the opiates.In addition,DEX has displayed potential neuroprotective properties.Purpose The aim of this review was to outline the advances of the use of DEX and provide practical guidance in neurosurgery clinical anesthesia.Content From the aspects of mechanism of action and clinical application,we reviewed the pharmacological characteristics and neuroprotective effects of DEX.Trend As a new anesthetic adjuvant,the clinical application of DEX in neurosurgery anesthesia is quite promising. Key words: Dexmedetomidine; Neurosurgery; Anesthesia; Neuroprotection

Effect of Magnesium Sulfate on the Total Anesthetic and Analgesic Requirements in Neurosurgery

Background: Anesthesia for neurosurgery requires balancing deep and effective anesthesia as well as postoperative analgesia versus the risks of delayed recovery and postoperative respiratory depression. This randomized, placebo-controlled, double-blind study was designed to evaluate the effect of magnesium sulfate on the total anesthetic and analgesic consumption using the clinical parameters in addition to the bispectral index (BIS) and neuromuscular monitoring using train-of-four (TOF). Patients and Methods: This study included 60 adult male and female patients, ASA physical status I and II, and undergoing neurosurgical procedures. Patients were randomly allocated into 2 equal groups. Patients in group I (magnesium group) received magnesium sulfate (20 mg/kg) as bolus dose over 5 minutes before induction of anesthesia, followed by 10 mg/kg/h as infusion. While patients in group II (control group) received saline with the same bolus and infusion rates. All patients were induced by fentanyl (2 μg/kg), propofol (1.5-2 mg/kg) and rocuronium in a dose of (0.6 mg/kg) to facilitate tracheal intubation. This was followed by continuous infusion of propofol (6-10 mg/kg/h) and fentanyl (1-2 μg/kg/h). Results: Results showed that total consumptions of fentanyl, propofol and rocuronium were significantly less (P < 0.05) in magnesium group when compared to control group. Recovery time was significantly shorter (P < 0.05) in magnesium group. Postoperative pain score as well as total analgesic requirement of morphine was significantly lower (P < 0.05) in magnesium group compared to control group. Conclusion: Magnesium sulfate reduces the total anesthetic and analgesic requirements as well as postoperative pain

Near infrared spectroscopy monitoring regional cerebral oxygen saturation and its clinical application

Background Near infrared spectroscopy (NIRS) is a new method for monitoring regional cerebral oxygen supply and demand balance with sensitive,fast,and real-time,continuous and noninvasive features.Some detail information on the regional cerebral cortex blood peffusion and oxygen supply and demand balance can be obtained by NIRS percutaneous detecting regional cerebral oxygen saturation (rSO2).Objective The aim of this review is to outline the near infrared spectroscopy for monitoring regional cerebral oxygen saturation and provide practical reference data for clinical work.Content This review includes three aspects:the principle of NIRS monitoring rSO2.its clinical application and affected factors.Trend NIRS monitoring rSO2 is mainly applied to monitor oxygen supply and demand balance and the changes of cerebral perfusion to prevent cerebral ischemia and hyperperfusion,and which has vast applied foreground on noninvasive monitoring intracranial pressure and evaluating the clinical treatment of cerebrovasospasm so on. Key words: Cerebral oxygen saturation; Near infrared spectroscopy; Cerebral ischemia perioperation; Neurosurgery anesthesia

Aprepitant versus ondansetron in preoperative triple-therapy treatment of nausea and vomiting in neurosurgery patients: study protocol for a randomized controlled trial

BackgroundThe incidence of postoperative nausea and vomiting (PONV) is 50% to 80% after neurosurgery. The common prophylactic treatment for postoperative nausea and vomiting is a triple therapy of droperidol, promethazine and dexamethasone. Newer, more effectives methods of prophylaxis are being investigated. We designed this prospective, double-blind, single-center study to compare the efficacy of ondansetron, a neurokinin-1 antagonist, and aprepitant, as a substitute for droperidol, in the prophylactic treatment of postoperative nausea and vomiting after neurosurgery.MethodsAfter obtaining institutional review board approval; 176 patients, 18 to 85 years of age with American Society of Anesthesiologists (ASA) classifications I to III, who did not receive antiemetics 24 h before surgery and were expected to undergo general anesthesia for neurosurgery lasting longer than 2 h were included in this study. After meeting the inclusion and exclusion criteria and providing written informed consent, patients were randomly assigned in a 1:1 ratio to one of two treatment groups: aprepitant or ondansetron. The objective of this study was to conduct a randomized, double-blind, double-dummy, parallel-group and single-center trial to compare and evaluate the efficacies of aprepitant versus ondansetron. Patients received oral aprepitant 40 mg OR oral dummy pill within 2 h prior to induction. At induction, a combination of intravenous dexamethasone 10 mg, promethazine 25 mg, and ondansetron 4 mg OR dummy injection was administered. Therefore, all patients received one dummy treatment and three active PONV prophylactic medications: dexamethasone 10 mg, promethazine 25 mg, and either aprepitant 40 mg OR ondansetron 4 mg infusion. The primary outcome measures were the episodes and severity of nausea and vomiting; administration of rescue antiemetic; and opioid consumption for 120 h postoperatively. Standard safety assessments included adverse event reports, physical and laboratory data, awakening time and duration of recovery from anesthesia.DiscussionThe results of this comparative study could potentially identify an improved treatment regimen that may decrease the incidence and severity of postoperative nausea and vomiting in patients undergoing neurosurgery. Also, this will serve to enhance patient recovery and overall satisfaction of neurosurgical patients in the immediate postoperative period.Trial registrationRegistered at The Ohio State University Biomedical Sciences Institutional Review Board: Protocol Number: 2007 H0053

A64 Can Quality be measured in Neuroanaesthesia?

Background: In 2008 the NHS published ‘High Quality Care for All: NHS Next Stage Review final report’ (Lord Darzi). This report described the concept of defining and measuring quality and has been promoted as the primary ethos driving the NHS. Staff at all levels should be able to measure services provided and improve the quality of care they deliver. They should also be able to provide patients with assurance that standards are monitored. Method: In 2009 the NHNN introduced quality measures across 31 subspecialties including neuroanaesthesia. Our department was asked to select 4 measures that defined quality of care for patients undergoing general anaesthesia for neurosurgery. The measures chosen by our department were: Pre-operative anaesthetic assessment to include cardiovascular risk Patient experience in the induction room World Health Organisation Safe Surgery Checklist compliance Post-operative pain score on leaving the recovery ward of 1 or less (range 0–4) We were required to set targets for these indicators and audit at regular intervals. The results of these audits would then inform local change and allow improvements to be made quickly. Results: Results have been collated over a 2 year period as shown in Table 1 (Quality Scorecard Results). Where targets were not met local improvement measures were put in place.Conclusion: As scorecards have become embedded in our department, we have learnt how to quantify the quality of the service offered to our patients. More importantly, we have learnt how to use this scorecard effectively to introduce change at a local level. This encourages leadership from the ‘bottom up’ allowing change to be responsive and locally driven. References High Quality Care for All: NHS next stage review final report. Lord Darzi, June 2008

Perioperative Exacerbation of Valproic Acid–Associated Hyperammonemia

We present a case of significant deterioration of chronic hyperammonemia after general anesthesia for neurosurgery despite aggressive treatment. Preoperative evaluation demonstrated that hyperammonemia was most likely related to valproic acid treatment. Genomic analysis revealed that the patient was heterozygotic for a missense polymorphism in the carbamoyl phosphate synthase 1 gene (4217C>A, rs1047891). This mutation was previously suggested to be associated with chronic hyperammonemia. Replacement of threonine with asparagine decreases the activity of carbamoyl phosphate synthase in the urea cycle. Genetic screening can potentially identify a population at risk before initiation of antiepileptic therapy.

Cottrell and Young's Neuroanesthesia, Fifth Edition.

University of California–San Diego, San Diego, California. blemkuil@ucsd.eduEdited by James E. Cottrell, M.D., F.R.C.A., William L. Young, M.D. Philadelphia, Mosby Elsevier, 2010. Pages: 480. Price: $199.00.Neuroanesthesia and perioperative care of the neurosurgical patient requires a thorough knowledge of anatomy, physiology, and pharmacology—in addition to familiarity with the surgical procedure, neuroimaging, and disease-specific pathophysiology. Integration and clinical application of this knowledge is essential to formulate an intelligent treatment plan as well as to predict, prevent, and manage potential complications.The fifth edition of Cottrell and Young's Neuroanesthesia comprehensively yet succinctly discusses the clinical aspects of neuroanesthesia as well as the science behind it. The chapter format, along with strategic use of tables, figures, and images, has resulted in a resource that is both visually inviting and helpful in facilitating knowledge retention. Each hardcover text is also accompanied by full online resource access.This newly released text has been substantially revised and updated from the 2001 edition. These many changes include William L. Young, M.D., as coeditor and 23 new authors. These additions provide fresh insight and expertise from a diversity of backgrounds, including basic and clinical scientists, neurointensivists, radiologists, neurosurgeons, and neuroanesthetists. The diversity of authors provides a well-balanced perspective to this text.The authors did an excellent job providing an up-to-date and comprehensive discussion of each topic without excessive detail that obscures salient points. Key studies that have helped shape clinical care are highlighted throughout and have been updated since the previous edition. Most chapters can be read easily in a single sitting, allowing easy assimilation of the information presented and placement within the broader clinical context.The breadth of the text is also appropriate, with attention given to all major clinical categories as well as a complement of supplementary chapters devoted to topics such as neuroradiology and neurophysiologic monitoring. In total, the fifth edition has 25 chapters, seven of which have been added since the 2001 edition. These include: “Pediatric Neuroanesthesia and Critical Care,”“Awake Craniotomy, Epilepsy, Minimally Invasive, and Robotic Surgery,” and “Anesthesia for Neurosurgery in the Pregnant Patient.”In summary, Cottrell and Young's Neuroanesthesia not only provides expert discussion concerning the foundational “pieces” of neuroanesthesia, it also helps with the integration and clinical application of these pieces. Although suitable and recommended for anesthesia trainees, this text goes far beyond any clinical handbook or board-preparation type resource. As Michael Todd, M.D., says in the Forward of this edition, this is a book for professionals.It is for those who want to provide the highest level of care for their patients by truly understanding why they do what they do. This approach to neuroanesthesia will allow one to adapt and handle any clinical situation that arises in a confident and intelligent fashion.Overall, this is an improved and updated version of an already successful neuroanesthesia text that has been around for many years. Although not without the occasional minor error inherent to all texts of this size, the editors have again produced a comprehensive and up-to-date resource that can be read cover to cover.In conclusion, I would recommend Cottrell and Young's Neuroanesthesia to resident trainees and to experienced clinicians who desire to update their knowledge and better understand the principles that guide their clinical actions. There are a number of textbooks of neuroanesthesia, each with a slightly different focus and each with a different breadth and depth. Of those, Cottrell and Young's Neuroanesthesia deserves the top shelf on the bookshelves of academic and clinical departments, as well as those of practitioners who desire the ready availability of a resource on the current state of the art of the practice of neuroanesthesia.University of California–San Diego, San Diego, California. blemkuil@ucsd.edu

Present status of awake anesthesia in neurosurgery

Present status of awake anesthesia in neurosurgery

Safety consideratrion of neurosurgery anesthesia for intraoperative magnetic resonance imaging

Objective To discuss the safety issues related to intraoperative magnetic resonance imaging (iMRI) in neurosurgical anesthesia.Methods We observed neurosurgery patients undergone MRI scanning in iMRI operation room preoperatively,intraoperatively and in diagnostic room shortly after operation between February to July in 2009. All patients were investigated for MRI contraindication preoperatively.The doctors and nurses participated in the procedure were trained strictly.The patients finished MRI scanning with general anesthesia.With the support of MRI-compatible machines(anesthetic machine,monitor,infusion pumps),safety issues related to scanning were recorded.Results All patients finished the MRI scanning safely,including 120 cases undergone intraoperative scanning(the average scannig times Wag 1.7 min)and 13 cases undergone postoperatively scannig.Patients remained stable during scanning.There was remarkably strong interference on electrocardiogram(ECG)in static MRI field and different scanning sequences,such as ECG baseline changed,muhiphagic ST-segment alterations andsevere arrhythmia,moreover the vital signs were stable.All anasthetic procedures were performed successfully,and the instruments were running well. There Wag no MRI-scanning releated complication.Conclusions During iMRI scanning,the safety considerations are important which need team-working.Anaesthetists play an important role to guarantee the patients'safety.Safety precautions and vigilance are necessary. Key words: Magnetic resonance imaging; Intraoperative period; Safety; Anesthesia; Neurosurgery

Malignant Hyperthermia during Desflurane - Succinylcholine Anesthesia for Neurosurgery: A case report

Desflurane has been known as a weak triggering anesthetic of malignant hyperthermia (MH). It may produce a delayed onset of symptoms. In addition the use of succinylcholine may aggravate occurrence of MH. The prolonged interval after exposure may occur more than 3 h after the induction of anesthesia. Although, the treatment of MH with Dantrolene is gold standard, it is not available in most countries. Because, MH has been rarely reported all over the world. So we present the first MH suspected case in our hospital.

Xenon anaesthesia in neurosurgery

Xenon anaesthesia in neurosurgery

Pharmacoeconomic analysis of xenon anesthesia in neurosurgery

Pharmacoeconomic analysis of xenon anesthesia in neurosurgery

Supplementary Use of Fentanyl in Propofol—Remifentanil Based Anesthesia in Neurosurgery

神経麻酔において鎮痛薬としてレミフェンタニルを主に使用した場合の, 適切なフェンタニルの併用量を検討することを目的とした. 対象は脳外科予定手術症例75例で, 閉頭の際にフェンタニルを2μg/kg (RF2群) または3μg/kg (RF3群) 併用し, 併用しなかった場合 (R群) と比較検討した. 麻酔はプロポフォール, レミフェンタニル, ベクロニウムにより, 導入・維持した. プロポフォール, フェンタニルの平均投与速度は群間で差がなかった. またフェンタニルを併用しても覚醒時間は延長しなかった. 抜管時の高血圧はRF3群で有意に少なかった. 術後疼痛の訴えはR群で2例, RF2群で1例あったが, RF3群ではなかった. 神経麻酔において, プロポフォール, レミフェンタニルによる麻酔にフェンタニルを併用する場合, 3μg/kgが適切と考えられた.