A retrospective cohort-matched comparison of conscious sedation versus general anesthesia for supratentorial glioma resection. Clinical article

Awake Versus Asleep Craniotomy for Patients With Eloquent Glioma: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Awake vs asleep craniotomy for patients with eloquent glioma is debatable. This systematic review and meta-analysis sought to compare awake vs asleep craniotomy for the resection of gliomas in the eloquent regions.

METHODS

MEDLINE and PubMed were searched from inception to December 13, 2022. Primary outcomes were the extent of resection (EOR), overall survival (month), progression-free survival (month), and rates of neurological deficit, Karnofsky performance score, and seizure freedom at the 3-month follow-up. Secondary outcomes were duration of operation (minute) and length of hospital stay (LOS) (day).

RESULTS

Fifteen studies yielded 2032 patients, from which 800 (39.4%) and 1232 (60.6%) underwent awake and asleep craniotomy, respectively. The meta-analysis concluded that the awake group had greater EOR (mean difference [MD] = MD = 8.52 [4.28, 12.76], P < .00001), overall survival (MD = 2.86 months [1.35, 4.37], P = .0002), progression-free survival (MD = 5.69 months [0.75, 10.64], P = .02), 3-month postoperative Karnofsky performance score (MD = 13.59 [11.08, 16.09], P < .00001), and 3-month postoperative seizure freedom (odds ratio = 8.72 [3.39, 22.39], P < .00001). Furthermore, the awake group had lower 3-month postoperative neurological deficit (odds ratio = 0.47 [0.28, 0.78], P = .004) and shorter LOS (MD = -2.99 days [-5.09, -0.88], P = .005). In addition, the duration of operation was similar between the groups (MD = 37.88 minutes [-34.09, 109.86], P = .30).

CONCLUSION

Awake craniotomy for gliomas in the eloquent regions benefits EOR, survival, postoperative neurofunctional outcomes, and LOS. When feasible, the authors recommend awake craniotomy for surgical resection of gliomas in the eloquent regions.

A Comparison of the Asleep-Awake Technique and Monitored Anesthesia Care During Awake Craniotomy: A 10-Year Analysis

Background Awake intracranial surgery with direct electrical stimulation (DES) is considered the gold standard for the resection of tumors affecting the eloquent areas of the brain. Awake craniotomy is a challenge for the anesthesiologist, as the patient's active cooperation is required throughout the operation. There are two frequent techniques, one is asleep-awake-asleep (AAA), and the other is called monitored anesthesia care (MAC). The AAA technique is the longer standing of the two and comprises general anesthesia followed by intraoperative awakening, which is necessary for neurological monitoring. In the present study, a comparison was made between the asleep-awake (AA) technique, a variation of the AAA anesthesia technique, and the MAC, which consists of a sedation that makes it possible to control pain and anxiety. Unlike the AA technique, the MAC does not involve the use of invasive airway devices. Objective The main objective was to contrast the two anesthetic management techniques for awake brain surgery used in our hospital. Methods A retrospective observational single-center study was performed consisting of a review of patient clinical records. The study sample comprised all patients above 18 years of age undergoing brain surgery through awake craniotomy between January 2013 and December 2022 at the Miguel Servet University Hospital (HUMS) in Zaragoza (Spain). Results Of the 79 patients included in the study, 39 were operated under AA anesthesia while the remaining 40 were operated under the MAC procedure. The main age of the participants was 52.8 years, the mean height was 169 cm, and the mean weight was 74.2 kg. No statistically significant differences were observed with respect to the patients' baseline characteristics, except for obesity which was more prevalent in the MAC group. In the MAC group, the airway was managed by means of nasal cannulas in all cases, with conversion to general anesthesia being required in only one instance. In the AA group, the laryngeal mask (LM) was used in 89.7% of the patients, and the endotracheal tube (ETT) in 10.3%. The surgical and anesthetic procedure duration was 15 and 20 minutes shorter in the MAC group, respectively. A reduction of almost 20 minutes in the anesthetic procedure and 15 minutes in the surgical one was observed. Tachycardia, desaturation, and airway complications were observed in four, five, and four patients respectively in the AA group but in none of the patients in the MAC group. The mean stay in the intensive care unit (ICU) and the mean postoperative hemoglobin levels between both groups were insignificant. Conclusions Both techniques analyzed in this study turned out to be equally safe and effective for brain tumor surgery in awake patients.

Resection of high-grade glioma involving language areas assisted by multimodal techniques under general anesthesia: a retrospective study

BACKGROUND

Multimodal techniques-assisted resection of glioma under general anesthesia (GA) has been shown to achieve similar clinical outcomes as awake craniotomy (AC) in some studies. In this study, we aim to validate the use of multimodal techniques can achieve the maximal safe resection of high-grade glioma involving language areas (HGILAs) under GA.

METHODS

HGILAs cases were reviewed and collected between January 2009 and December 2020 in our center. Patients were separated into multimodal group (using neuronavigation, intraoperative MRI combined with direct electrical stimulation [DES] and neuromonitoring [IONM]) and conventional group (neuronavigation alone) and clinical outcomes were compared between groups. Studies of HGILAs were reviewed systematically and the meta-analysis results of previous (GA or AC) studies were compared with our results.

RESULTS

Finally, there were 263 patients in multimodal group and 137 patients in conventional group. Compared to the conventional group, the multimodal group achieved the higher median EOR (100% versus 94.32%, P < 0.001) and rate of gross total resection (GTR) (73.8% versus 36.5%, P < 0.001) and the lower incidence of permanent language deficit (PLD) (9.5% versus 19.7%, P = 0.004). The multimodal group achieved the longer median PFS (16.8 versus 10.3 months, P < 0.001) and OS (23.7 versus 15.7 months, P < 0.001) than the conventional group. The multimodal group achieved a higher rate of GTR than the cohorts in previous multimodal studies under GA and AC (73.8% versus 55.7% [95%CI 32.0-79.3%] versus 53.4% [35.5-71.2%]). The multimodal group had a lower incidence of PLD than the cohorts in previous multimodal studies under GA (9.5% versus 14.0% [5.8-22.1%]) and our incidence of PLD was a little higher than that of previous multimodal studies under AC (9.5% versus 7.5% [3.7-11.2%]). Our multimodal group also achieved a relative longer survival than previous studies.

CONCLUSIONS

Surgery assisted by multimodal techniques can achieve maximal safe resection for HGILAs under GA. Further prospective studies are needed to compare GA with AC for HGILAs.

Awake Craniotomy in Africa: A Scoping Review of Literature and Proposed Solutions to Tackle Challenges

BACKGROUND

Awake craniotomy (AC) is a common neurosurgical procedure for the resection of lesions in eloquent brain areas, which has the advantage of avoiding general anesthesia to reduce associated complications and costs. A significant resource limitation in low- and middle-income countries constrains the usage of AC.

OBJECTIVE

To review the published literature on AC in African countries, identify challenges, and propose pragmatic solutions by practicing neurosurgeons in Africa.

METHODS

We conducted a scoping review under Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Scoping Review guidelines across 3 databases (PubMed, Scopus, and Web of Science). English articles investigating AC in Africa were included.

RESULTS

Nineteen studies consisting of 396 patients were included. Egypt was the most represented country with 8 studies (42.1%), followed by Nigeria with 6 records (31.6%). Glioma was the most common lesion type, corresponding to 120 of 396 patients (30.3%), followed by epilepsy in 71 patients (17.9%). Awake-awake-awake was the most common protocol used in 7 studies (36.8%). Sixteen studies (84.2%) contained adult patients. The youngest reported AC patient was 11 years old, whereas the oldest one was 92. Nine studies (47.4%) reported infrastructure limitations for performing AC, including the lack of funding, intraoperative monitoring equipment, imaging, medications, and limited human resources.

CONCLUSION

Despite many constraints, AC is being safely performed in low-resource settings. International collaborations among centers are a move forward, but adequate resources and management are essential to make AC an accessible procedure in many more African neurosurgical centers.

Review of Intraoperative Adjuncts for Maximal Safe Resection of Gliomas and Its Impact on Outcomes

Maximal safe resection is the mainstay of treatment in the neurosurgical management of gliomas, and preserving functional integrity is linked to favorable outcomes. How these modalities differ in their effectiveness on the extent of resection (EOR), survival, and complications remains unknown. A systematic literature search was performed with the following inclusion criteria: published between 2005 and 2022, involving brain glioma surgery, and including one or a combination of intraoperative modalities: intraoperative magnetic resonance imaging (iMRI), awake/general anesthesia craniotomy mapping (AC/GA), fluorescence-guided imaging, or combined modalities. Of 525 articles, 464 were excluded and 61 articles were included, involving 5221 glioma patients, 7(11.4%) articles used iMRI, 21(36.8%) used cortical mapping, 15(24.5%) used 5-aminolevulinic acid (5-ALA) or fluorescein sodium, and 18(29.5%) used combined modalities. The heterogeneity in reporting the amount of surgical resection prevented further analysis. Progression-free survival/overall survival (PFS/OS) were reported in 18/61(29.5%) articles, while complications and permanent disability were reported in 38/61(62.2%) articles. The reviewed studies demonstrate that intraoperative adjuncts such as iMRI, AC/GA mapping, fluorescence-guided imaging, and a combination of these modalities improve EOR. However, PFS/OS were underreported. Combining multiple intraoperative modalities seems to have the highest effect compared to each adjunct alone.

Clinical study of multifunctional laryngeal mask in airway interventional therapy

OBJECTIVE

This study is conducted to evaluate the efficacy and safety of using multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy.

METHODS

A total of 200 patients receiving airway interventional therapy were enrolled in this retrospective study and were divided into 2 groups (group M and group P) by doctors in our hospital to compare the effect of different laryngeal masks. Group M used common laryngeal masks and an anesthesia machine for positive pressure ventilation while group P took multifunctional intubation laryngeal masks and used a jet ventilator for normal frequency jet ventilation. The patients' mean arterial pressure, heart rate, arterial oxygen partial pressure (PaO2) and arterial carbon dioxide partial pressure (PaCO2), and the operation time, recovery score and the patients' and doctors' satisfaction levels were compared between the 2 groups.

RESULTS

Both groups were hemodynamically stable, and their PaO2 levels were significantly higher before the operation than that during and after the operation (P < .05). Compared with group M, the PaCO2 level of group P was more stable both during and after the operation, and this difference was statistically significant (P < .05). There was no statistically significant difference in terms of the 2 group's operating time, recovery score, and patients' satisfaction levels (P > .05). However, the satisfaction levels of doctors in group P were higher than that in group M, and this difference was statistically significant (P < .05).

CONCLUSION

As statistics show, the intraoperative hemodynamics and PaO2 and PaCO2 levels were stable, and patients, surgeons and anesthesia operators were satisfied. Therefore, it is feasible to apply multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy and it is a safe and ideal way to ensure ventilation.

The PROGRAM study: awake mapping versus asleep mapping versus no mapping for high-grade glioma resections: study protocol for an international multicenter prospective three-arm cohort study

INTRODUCTION

The main surgical dilemma during glioma resections is the surgeon's inability to accurately identify eloquent areas when the patient is under general anaesthesia without mapping techniques. Intraoperative stimulation mapping (ISM) techniques can be used to maximise extent of resection in eloquent areas yet simultaneously minimise the risk of postoperative neurological deficits. ISM has been widely implemented for low-grade glioma resections backed with ample scientific evidence, but this is not yet the case for high-grade glioma (HGG) resections. Therefore, ISM could thus be of important value in HGG surgery to improve both surgical and clinical outcomes.

METHODS AND ANALYSIS

This study is an international, multicenter, prospective three-arm cohort study of observational nature. Consecutive HGG patients will be operated with awake mapping, asleep mapping or no mapping with a 1:1:1 ratio. Primary endpoints are: (1) proportion of patients with National Institute of Health Stroke Scale deterioration at 6 weeks, 3 months and 6 months after surgery and (2) residual tumour volume of the contrast-enhancing and non-contrast-enhancing part as assessed by a neuroradiologist on postoperative contrast MRI scans. Secondary endpoints are: (1) overall survival and (2) progression-free survival at 12 months after surgery; (3) oncofunctional outcome and (4) frequency and severity of serious adverse events in each arm. Total duration of the study is 5 years. Patient inclusion is 4 years, follow-up is 1 year.

ETHICS AND DISSEMINATION

The study has been approved by the Medical Ethics Committee (METC Zuid-West Holland/Erasmus Medical Center; MEC-2020-0812). The results will be published in peer-reviewed academic journals and disseminated to patient organisations and media.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov ID number NCT04708171 (PROGRAM-study), NCT03861299 (SAFE-trial).

Awake craniotomy in brain tumors - Technique systematization and the state of the art

The anesthesia for awake craniotomy (AC) is a consecrated anesthetic technique that has been perfected over the years. Initially used to map epileptic foci, it later became the standard technique for the removal of glial neoplasms in eloquent brain areas. We present an AC anesthesia technique consisting of three primordial times, called awake-asleep-awake, and their respective particularities, as well as delve into the anesthetic medications used. Its use in patients with low and high-grade gliomas was favorable for the resection of tumors within the functional boundaries of patients, with shorter hospital stay and lower direct costs. The present study aims to systematize the technique based on the experience of the largest philanthropic hospital in Latin America and discusses the most relevant aspects that have consolidated this technique as the most appropriate in the surgery of gliomas in eloquent areas.

Clinical Pearls and Methods for Intraoperative Awake Language Mapping

Intraoperative language mapping of tumor and peritumor tissue is a well-established technique for avoiding permanent neurological deficits and maximizing extent of resection. Although there are several components of language that may be tested intraoperatively (eg, naming, writing, reading, and repetition), there is a lack of consistency in how patients are tested intraoperatively as well as the techniques involved to ensure safety during an awake procedure. Here, we review appropriate patient selection, neuroanesthetic techniques, cortical and subcortical language mapping stimulation paradigms, and selection of intraoperative language tasks used during awake craniotomies. We also expand on existing language mapping reviews by considering how intensity and timing of electrical stimulation may impact interpretation of mapping results.

Analysis of Intraoperative Seizures During Bipolar Brain Mapping in Eloquent Areas: Intraoperative Seizures in brain mapping

OBJECTIVES

Awake Craniotomy (AC) is a very well described technique that is performed to make an adequate tumor resection preserving the functionality of the patient. Intraoperative Seizures (IS) are reported as a failure of such procedure. We analyze the incidence and risk factor during AC.

METHODS

We made a review of the database of the National Institute of Neurology and Neurosurgery between January 2017 and May 2019 for intrinsic tumors located in eloquent areas of the brain. An analysis of ISconcerning the clinical history, clinical presentation, imaging techniques, histological findings and surgical technique was made. The factors associated with Mapping Failure (MF) were also evaluated.

RESULTS

45 patients were included of whom 7 patients (15.6%) developed IS after cortical-subcortical stimulation, 5 presented partial motor seizures (11.1%) and 2 experimented generalized secondary seizures (4.5%). Of the patients that had a MF, one patient (14%) was due to generalized tonic-clonic seizures which couldn't be managed by cold saline irrigation and administration of anti-seizures drugs and was then converted to a general anesthetic technique. We observed that the patients that had a bigger tumoral volume (112.2 cm3 85.3, P = 0,07) had a bigger positive relation in presenting IS, having a peak sensibility and specificity above 70 cc (ROC).

CONCLUSIONS

In our analysis IS are more common in patients with high presurgical tumor volume. Even though the majority of the patients that presented IS didn't develop MF, it is important to acknowledge that the multidisciplinary group in the operating room must be prepared to detect these complications, treat them promptly and avoid MF.

Glioma surgery with awake language mapping versus generalized anesthesia: a systematic review

Awake craniotomy with language mapping is being increasingly applied to avoid postoperative language dysfunctions worldwide. However, the effectiveness and reliability of this technique remain unclear due to the paucity of studies comparing the awake craniotomy with general anesthesia. To determine the benefit of awake craniotomy for language, motor, and neurological functions, as well as other clinical outcomes, we searched Medline, Embase, the Cochrane Library, and the Chinese Biomedical Literature Database up to December 2019. Gray literatures were also searched. We included randomized and non-randomized controlled studies comparing awake craniotomy versus general anesthetic resection and reporting the language and neurological outcomes. Ten studies with 833 patients were included in the meta-analysis. The pooled risk ratio (RR) suggested no significant differences in language and neurological outcomes between general anesthesia group and awake craniotomy group without electrical stimulation. Awake craniotomy with electrical stimulation, however, was associated with improved late language and neurological outcomes (≥ 3 months) versus general anesthesia with pooled RR of 0.44 (95% CI = 0.20-0.96) and 0.49 (95% CI = 0.30-0.79), respectively. Awake craniotomy with electrical stimulation was also associated with better extent of resection with the pooled RR of 0.81 (95%CI = 0.71-0.92) and shorter hospital stay duration with the pooled weighted mean difference (WMD) of - 1.14 (95%CI = - 1.80 to - 0.48). This meta-analysis suggested that the application of awake craniotomy with electrical stimulation during glioma resection is associated with lower risks of long-term neurological and language deficits and higher extent of tumor resection, as well as shorter hospital stay duration.

Awake craniotomy for resection of supratentorial glioblastoma: a systematic review and meta-analysis

Background

The goal of glioblastoma (GBM) surgery is to maximize the extent of resection (EOR) while minimizing postoperative neurological complications. Awake craniotomy (AC) has been demonstrated to achieve this goal for low-grade gliomas in or near eloquent areas. However, the efficacy of AC for GBM resection has not been established. Therefore, we aimed to investigate the outcomes of AC for surgical resection of GBM using a systematic review and meta-analysis of published studies.

Methods

Systematic searches of Ovid MEDLINE, Embase, Cochrane Controlled Register of Controlled Trials, and PubMed were performed from database inception to September 14, 2019 for published studies reporting outcomes of AC for GBM resection. Outcome measures analyzed included EOR and the event rate of postoperative neurological deficits.

Results

A total of 1928 unique studies were identified. Fourteen studies reporting 278 patients were included in our meta-analysis. Mean age of patients was 46.9 years (95% confidence interval [CI]: 43.9–49.9). Early and late postoperative neurological deficits occurred in 34.5% (95% CI: 21.9–48.2) and 1.9% (95% CI: 0.0–9.2) of patients, respectively. Pooled percentage of gross total resection (GTR) was 74.7% (95% CI: 66.7–82.1), while the pooled percentage reduction in tumor volume was 95.3% (95% CI: 92.2–98.4).

Conclusions

Limited current evidence suggests that the use of AC for resection of supratentorial GBM is associated with a low rate of persistent neurological deficits while achieving an acceptable rate of GTR. Our findings demonstrate the potential viability of AC in GBM resection and highlight the need for further research on this topic.

Laser Ablation of Abnormal Neurological Tissue Using Robotic Neuroblate System (LAANTERN): Procedural Safety and Hospitalization

BACKGROUND

Stereotactic laser ablation (SLA) has demonstrated potential utility for a spectrum of difficult to treat neurosurgical pathologies in multiple small and/or retrospective single-institutional series. Here, we present the safety profile of SLA of intracranial lesions from the Laser Ablation of Abnormal Neurological Tissue using Robotic NeuroBlate System (LAANTERN; Monteris Medical) multi-institutional, international prospective observational registry.

OBJECTIVE

To determine the procedural safety of SLA for intracranial lesions.

METHODS

Prospective procedural safety and hospitalization data from the first 100 treated LAANTERN patients was collected and analyzed.

RESULTS

Mean age and baseline Karnofsky Performance Status (KPS) were 51(± 17) yr and 83(± 15), respectively. In total, 81.2% of patients had undergone prior surgical or radiation treatment. Most patients had a single lesion (79%) ablated through 1 burr hole (1.2 ± 0.7 per patient), immediately following a lesion biopsy. In total, >90% of the lesion was ablated in 72% of treated lesions. Average total procedural time was 188.2 ± 69.6 min, and average blood loss was 17.7 ± 55.6 ccs. The average length of intensive care unit (ICU) and hospital stays before discharge were 38.1 ± 62.7 h and 61.1 ± 87.2 h, respectively. There were 5 adverse events (AEs) attributable to SLA (5/100; 5%). After the procedure, 84.8% of patients were discharged home. There was 1 mortality within 30 d of the procedure (1/100; 1%), which was not attributable to SLA.

CONCLUSION

SLA is a safe, minimally invasive procedure with favorable postprocedural ICU and hospital utilization profiles.

Incidence and predicting factors of perioperative complications during monitored anesthesia care for awake craniotomy

STUDY OBJECTIVE

To assess incidence and predicting factors of awake craniotomy complications.

DESIGN

Retrospective cohort study.

SETTING

Operating room and Post Anesthesia Care unit.

PATIENTS

162 patients who underwent 188 awake craniotomy procedures for brain tumor, ASA I to III, with monitored anesthesia care.

MEASUREMENTS

We classified procedures in 3 groups: major event group, minor event group, and no event group. Major events were defined as respiratory failure requiring face mask or invasive ventilation; hemodynamic instability treated by vasoactive drugs, or bradycardia treated by atropine, bleeding >500 ml, transfusion, gaseous embolism, cardiac arrest; seizure, cerebral edema, or any events leading to stopping of the cerebral mapping. Minor event was defined as any complication not classified as major. Multivariate logistic regression was used to determine predicting factors of major complication, adjusted for age and ASA score.

MAIN RESULTS

45 procedures (24%) were classified in major event group, 126 (67%) in minor event group, and 17 (9%) in no event group. Seizure was the main complication (n = 13). Asthma (odds ratio: 10.85 [1.34; 235.6]), Remifentanil infusion (odds ratio: 2.97 [1.08; 9.85]) and length of the operation after the brain mapping (odds ratio per supplementary minute: 1.01 [1.01; 1.03]) were associated with major events.

CONCLUSIONS

Previous medical history of asthma, remifentanil infusion and a long duration of neurosurgery after cortical mapping appear to be risk factors for major complications during AC.

Awake glioma surgery: technical evolution and nuances

INTRODUCTION

Multiple studies have demonstrated that improved extent of resection is associated with longer overall survival for patients with both high and low grade glioma. Awake craniotomy was developed as a technique for maximizing resection whilst preserving neurological function.

METHODS

We performed a comprehensive review of the literature describing the history, indications, techniques and outcomes of awake craniotomy for patients with glioma.

RESULTS

The technique of awake craniotomy evolved to become an essential tool for resection of glioma. Many perceived contraindications can now be managed. We describe in detail our preferred technique, the testing paradigms utilized, and critically review the literature regarding functional and oncological outcome.

CONCLUSIONS

Awake craniotomy with mapping has become the gold standard for safely maximizing extent of resection for tumor in or near eloquent brain. Cortical and subcortical mapping methods have been refined and the technique is associated with an extremely low rate of complications.

Comparison of Motor Outcome in Patients Undergoing Awake vs General Anesthesia Surgery for Brain Tumors Located Within or Adjacent to the Motor Pathways

BACKGROUND

Surgical removal of intra-axial brain tumors aims at maximal tumor resection while preserving function. The potential benefit of awake craniotomy over craniotomy under general anesthesia (GA) for motor preservation is yet unknown.

OBJECTIVE

To compare the clinical outcomes of patients who underwent surgery for perirolandic tumors while either awake or under GA.

METHODS

Between 2004 and 2015, 1126 patients underwent surgical resection of newly diagnosed intra-axial tumors in a single institution. Data from 85 patients (44 awake, 41 GA) with full dataset who underwent resections for perirolandic tumors were retrospectively analyzed.

RESULTS

Identification of the motor cortex required significantly higher stimulation thresholds in anesthetized patients (9.1 ± 4 vs 6.2 ± 2.7 mA for awake patients, P = .0008). There was no group difference in the subcortical threshold for motor response used to assess the proximity of the lesion to the corticospinal (pyramidal) tract. High-grade gliomas were the most commonly treated pathology. The extent of resection and residual tumor volume were not different between groups. Postoperative motor deficits were more common in the anesthetized patients at 1 wk (P = .046), but no difference between the groups was detected at 3 mo. Patients in the GA group had a longer mean length of hospitalization (10.3 vs 6.7 d for the awake group, P = .003).

CONCLUSION

Awake craniotomy results in a better early postoperative motor outcome and shorter hospitalization compared with patients who underwent the same surgery under GA. The finding of higher cortical thresholds for the identification of the motor cortex in anesthetized patients may suggest an inhibitory effect of anesthetic agents on motor function.

The SAFE-trial: Safe surgery for glioblastoma multiforme: Awake craniotomy versus surgery under general anesthesia. Study protocol for a multicenter prospective randomized controlled trial

BACKGROUND

Surgery of GBM nowadays is usually performed under general anesthesia (GA) and resections are often not as aggressive as possible, due to the chance of seriously damaging the patient with a rather low life expectancy. A surgical technique optimizing resection of the tumor in eloquent areas but preventing neurological deficits is necessary to improve survival and quality of life in these patients. Awake craniotomy (AC) with the use of cortical and subcortical stimulation has been widely implemented for low-grade glioma resections (LGG), but not yet for GBM. AC has shown to increase resection percentage and preserve quality of life in LGG and could thus be of important value in GBM surgery.

METHODS/DESIGN

This study is a prospective, multicenter, randomized controlled trial (RCT). Consecutive patients with a glioblastoma in or near eloquent areas (Sawaya grading II/III) will be 1:1 randomized to awake craniotomy or craniotomy under general anesthesia. 246 patients will be included in neurosurgical centers in the Netherlands and Belgium. Primary end-points are: 1) Postoperative neurological morbidity and 2) Proportion of patients with gross-total resections. Secondary end-points are: 1) Health-related quality of life; 2) Progression-free survival (PFS); 3) Overall survival (OS) and 4) Frequency and severity of Serious Adverse Effects in each group. Also, a cost-benefit analysis will be performed. All patients will receive standard adjuvant treatment with concomitant chemoradiotherapy.

DISCUSSION

This RCT should demonstrate whether AC is superior to craniotomy under GA on neurological morbidity, extent of resection and survival for glioblastoma resections in or near eloquent areas.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT03861299 Netherlands Trial Register (NTR): NL7589.

Preservation of cranial nerve function following awake surgery for benign brain tumors in 22 consecutive patients

BACKGROUND

Preservation of cranial nerve function in patients with benign tumors such as meningiomas and vestibular schwannomas remains difficult following microsurgery.

METHODS

In this study, awake surgery was performed in 22 consecutive patients with meningiomas or vestibular schwannomas that compressed cranial nerves (I-XII). Improved, unchanged, or deteriorated cranial nerve function after surgery was evaluated.

RESULTS

The function of 44 cranial nerves in 22 consecutive patients who underwent awake surgery for meningiomas or vestibular schwannomas improved, was unchanged, or deteriorated in eight, 35, and one nerves, respectively. Regarding the function of the olfactory (Ist) nerve, which is difficult to preserve, hyposmia improved after surgery in two patients with olfactory groove meningiomas. Regarding the auditory (VIIIth) nerve, which is also difficult to preserve, the function was improved, unchanged, or deteriorated after surgery in two, 11, and one patients, respectively, with cerebello-pontine angle meningiomas or vestibular schwannomas. In all patients with serviceable auditory function before surgery, function was preserved after surgery. In the same patients, the function of the facial (VIIth) nerve was also preserved after surgery in all patients.

CONCLUSIONS

These results suggest that awake surgery for benign brain tumors such as meningiomas and vestibular schwannomas is associated with low patient morbidity regarding cranial nerve function.

Awake Surgical Management of Third Ventricular Tumors: A Preliminary Safety, Feasibility, and Clinical Applications Study

BACKGROUND

Endoscopic and microneurosurgical approaches to third ventricular lesions are commonly performed under general anesthesia.

OBJECTIVE

To report our initial experience with awake transsulcal parafascicular corridor surgery (TPCS) of the third ventricle and its safety, feasibility, and limitations.

METHODS

A total of 12 cases are reviewed: 6 colloid cysts, 2 central neurocytomas, 1 papillary craniopharyngioma, 1 basal ganglia glioblastoma, 1 thalamic glioblastoma, and 1 ependymal cyst. Lesions were approached using TPCS through the superior frontal sulcus. Pre-, intra-, and postoperative neurocognitive (NC) testing were performed on all patients.

RESULTS

No cases required conversion to general anesthesia. Awake anesthesia changed intraoperative management in 4/12 cases with intraoperative cognitive changes that required port re-positioning; 3/4 recovered. Average length of stay (LOS) was 6.1 d ± 6.6. Excluding 3 outliers who had preoperative NC impairment, the average LOS was 2.5 d ± 1.2. Average operative time was 3.00 h ± 0.44. Average awake anesthesia time was 5.05 h ± 0.54. There were no mortalities.

CONCLUSION

This report demonstrated the feasibility and safety of awake third ventricular surgery, and was not limited by pathology, size, or vascularity. The most significant factor impacting LOS was preoperative NC deficit. The most significant risk factor predicting a permanent NC deficit was preoperative 2/3 domain impairment combined with radiologic evidence of invasion of limbic structures – defined as a “NC resilience/reserve” in our surgical algorithm. Larger efficacy studies will be required to demonstrate the validity of the algorithm and impact on long-term cognitive outcomes, as well as generalizability of awake TPCS for third ventricular surgery.

Awake craniotomy versus craniotomy under general anesthesia without surgery adjuncts for supratentorial glioblastoma in eloquent areas: a retrospective matched case-control study

BACKGROUND

Awake craniotomy with electrocortical and subcortical mapping (AC) has become the mainstay of surgical treatment of supratentorial low-grade gliomas in eloquent areas, but not as much for glioblastomas.

OBJECTIVE

This retrospective controlled-matched study aims to determine whether AC increases gross total resections (GTR) and decreases neurological morbidity in glioblastoma patients as compared to resection under general anesthesia (GA, conventional).

METHODS

Thirty-seven patients with glioblastoma undergoing AC were 1:3 controlled-matched with 111 patients undergoing GA for glioblastoma resection. The two groups were matched for age, gender, preoperative Karnofsky Performance Score (KPS), preoperative tumor volume, tumor location, and type of adjuvant treatment. Primary outcomes were extent of resection and the rate of postoperative complications. The secondary outcome was overall postoperative survival.

RESULTS

After matching, there were no significant differences in clinical variables between groups. Extent of resection was significantly higher in the AC group: mean extent of resection in the AC group was 94.89% (SD = 10.57) as compared to 70.30% (SD = 28.37) in the GA group (p = 0.0001). Furthermore, the mean rate of late minor postoperative complications in the AC group (0.03; SD = - 0.16) was significantly lower than in the GA group (0.15; SD = 0.39) (p = 0.05). No significant differences between groups were found for the other subgroups of postoperative complications. Moreover, overall postoperative survival did not differ between groups (p = 0.297).

CONCLUSION

These findings suggest that resection of glioblastoma using AC is associated with significantly greater extent of resection and less late minor postoperative complications as compared with craniotomy under GA without the use of surgery adjuncts. However, due to certain limitations inherent to our study design (selection bias) and the absence of the use of surgery adjuncts in the GA group, we advocate for a prospective study to further build upon this evidence and study the use of AC in glioblastoma patients.

Conscious sedation with dexmedetomidine compared with asleep-awake-asleep craniotomies in glioma surgery: an analysis of 180 patients

OBJECTIVEAwake craniotomies have become a feasible tool over time to treat brain tumors located in eloquent regions. Different techniques have been applied in neurooncology centers. Both "asleep-awake-asleep" (asleep) and "conscious sedation" were used subsequently at the authors' neurosurgical department. Since 2013, the authors have only performed conscious sedation surgeries, predominantly using the α2-receptor agonist dexmedetomidine as the anesthetic drug. The aim of this study was to compare both mentioned techniques and evaluate the clinical use of dexmedetomidine in the setting of awake craniotomies for glioma surgery.METHODSThe authors retrospectively analyzed patients who underwent operations either under the asleep condition using propofol-remifentanil or under conscious sedation conditions using dexmedetomidine infusions. In the asleep group patients were intubated with a laryngeal mask and extubated for the assessment period. Adverse events, as well as applied drugs with doses and frequency of usage, were recorded.RESULTSFrom 224 awake surgeries between 2009 and 2015, 180 were performed for the resection of gliomas and included in the study. In the conscious sedation group (n = 75) significantly fewer opiates (p < 0.001) and vasoactive (p < 0.001) and antihypertensive (p < 0.001) drugs were used in comparison with the asleep group (n = 105). Furthermore, the postoperative length of stay (p < 0.001) and the surgical duration (p < 0.001) were significantly lower in the conscious sedation group.CONCLUSIONSUse of dexmedetomidine creates excellent conditions for awake surgeries. It sedates moderately and acts as an anxiolytic. Thus, after ceasing infusion it enables quick and reliable clinical neurological assessment of patients. This might lead to reducing the amount of administered antihypertensive and vasoactive drugs as well as the length of hospitalization, while likely ensuring more rapid surgery.

Awake craniotomy in glioma surgery: is it necessary?

INTRODUCTION

The awake craniotomy has evolved from its humble beginnings in ancient cultures to become one of the most eloquent modern neurosurgical procedures. The development of intraoperative mapping techniques like direct electrostimulation of the cortex and subcortical white matter have further argued for its place in the neurosurgeon's armamentarium. Yet the suitability of the awake craniotomy with intraoperative functional mapping (ACWM) to optimize oncofunctional balance after peri-eloquent glioma resection continues to be a topic of active investigation as new methods of intraoperative monitoring and some unfavorable outcome data question its necessity.

EVIDENCE ACQUISITION

The neurosurgery and anesthesiology literatures were scoured for English-language studies that analyzed or reviewed the ACWM or its components as applied to glioma surgery via the PubMed, ClinicalKey, and OvidMEDLINE® databases or via direct online searches of journal archives.

EVIDENCE SYNTHESIS

Information on background, conceptualization, standard techniques, and outcomes of the ACWM were provided and compared. We parceled the procedure into its components and qualitatively described positive and negative outcome data for each. Findings were presented in the context of each study without attempt at quantitative analysis or reconciliation of heterogeneity between studies. Certain illustrative studies were highlighted throughout the review. Overarching conclusions were drawn based on level of evidence, expert opinion, and predominate concordance of data across studies in the literature.

CONCLUSIONS

Most investigators and studies agree that the ACWM is the best currently available approach to optimize oncofunctional balance in this difficult-to-treat patient population. This qualitative review synthesizes the most currently available data on the topic to provide contemporaneous insight into how and why the ACWM has become a favorite operation of neurosurgeons worldwide for the resection of gliomas from eloquent brain.

Awake craniotomy without sedation in treatment of patients with lesional epilepsy

BACKGROUND

The use of awake craniotomy for surgical treatment of epilepsy was applied in surgery of convexital tumors, arteriovenous malformations, some superficial aneurysms, and stereotactic neurosurgery. The aim of this study was to show the advantages of awake craniotomy without sedation, accompanied by intraoperative neurophysiological monitoring in patients with symptomatic epilepsy.

METHODS

This article describes the results of surgical treatment in 41 patients with various pathologies; 31 among them suffered from epilepsy.

RESULTS

Most frequently, the pathological foci were located in frontal and parietal lobes nearby eloquent brain areas. Irrespective of damage location, simple partial and complex partial seizures were seen almost with the same frequency. Intraoperative mapping of eloquent cortical areas and subcortical tracts without sedation resulted in total resection of pathological area in 75% of cases with low rate of permanent neurological deficit (two patients). Minor perioperative complications, including the decrease in blood pressure in six patients and intraoperative convulsions in two patients, were handled and did not led to operation termination or anesthesia conversion. Excellent seizures control (Engel 1) was achieved in 80% of patients with available catamnesis.

CONCLUSION

Thus, the proposed method allows eliminating the complications associated with sedation and provides radical resection of pathological epileptogenic foci with low complication rate.

Awake Craniotomy vs Craniotomy Under General Anesthesia for Perirolandic Gliomas: Evaluating Perioperative Complications and Extent of Resection

BACKGROUND

A craniotomy with direct cortical/subcortical stimulation either awake or under general anesthesia (GA) present 2 approaches for removing eloquent region tumors. With a reported higher prevalence of intraoperative seizures occurring during awake resections of perirolandic lesions, oftentimes, surgery under GA is chosen for these lesions.

OBJECTIVE

To evaluate a single-surgeon's experience with awake craniotomies (AC) vs surgery under GA for resecting perirolandic, eloquent, motor-region gliomas.

METHODS

Between 2005 and 2015, a retrospective analysis of 27 patients with perirolandic, eloquent, motor-area gliomas that underwent an AC were case-control matched with 31 patients who underwent surgery under GA for gliomas in the same location. All patients underwent direct brain stimulation with neuromonitoring and perioperative risk factors, extent of resection, complications, and discharge status were assessed.

RESULTS

The postoperative Karnofsky Performance Score (KPS) was significantly lower for the GA patients at 81.1 compared to the AC patients at 93.3 ( P = .040). The extent of resection for GA patients was 79.6% while the AC patients had an 86.3% resection ( P = .136). There were significantly more 100% total resections in the AC patients 25.9% compared to the GA group (6.5%; P = .041). Patients in the GA group had a longer mean length of hospitalization of 7.9 days compared to the AC group at 4.2 days ( P = .049).

CONCLUSION

We show that AC can be performed with more frequent total resections, better postoperative KPS, shorter hospitalizations, as well as similar perioperative complication rates compared to surgery under GA for perirolandic, eloquent motor-region glioma.

Effect of anesthesia depth on postoperative clinical outcome in patients with supratentorial tumor (DEPTH): study protocol for a randomized controlled trial

INTRODUCTION

Recent studies have shown that deep anaesthesia is associated with poor outcomes. However, no randomised controlled trials have been conducted to test the causality in patients undergoing brain tumour resection.

METHODS AND ANALYSIS

DEPTH is a multicenter, randomised, parallel-group, blind trial. The depth of general anaesthesia will be monitored using the bispectral index (BIS). Patients elected for supratentorial tumour resection will be randomly allocated to the deep or the light anaesthesia group in which the target BIS value is 35 or 50, respectively. BIS will be maintained at the target value for more than 90% of the total anaesthesia period. The primary outcome is the disability-free survival rate at postoperative 30 days and 1 year. The secondary outcomes are the mortality and morbidity within 30 days after surgery.

ETHICS APPROVAL AND DISSEMINATION

Ethical approval has been granted by the Medical Ethics Committee of Beijing Tiantan Hospital, Capital Medicine University. The reference number is KY2016-059-02. The results of this study will be disseminated through presentations at scientific conferences and publication in scientific journals.

TRIAL REGISTRATION

NCT03033693.

Preservation of hearing following awake surgery via the retrosigmoid approach for vestibular schwannomas in eight consecutive patients

BACKGROUND

Hearing preservation in patients with vestibular schwannomas remains difficult by microsurgery or radiosurgery.

METHOD

In this study, awake surgery via the retrosigmoid approach was performed for vestibular schwannomas (volume, 11.6 ± 11.2 ml; range, 1.3-26.4 ml) in eight consecutive patients with preoperative quartering of pure tone audiometry (PTA) of 53 ± 27 dB.

RESULTS

After surgery, hearing was preserved in seven patients and improved in one patient. The postoperative quartering PTA was 51 ± 21 dB. Serviceable hearing (class A + B + C) using the American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS) classification was preserved in all patients. Preoperative useful hearing (AAO-HNS class A + B) was observed in three patients, and useful hearing was preserved in all three of these patients after surgery. In addition, useful facial nerve function (House-Blackmann Grade 1) was preserved in all patients.

CONCLUSIONS

These results suggest that awake surgery for vestibular schwannomas is associated with low patient morbidity, including with respect to hearing and facial nerve function.

Patients' Perioperative Experience of Awake Deep-Brain Stimulation for Parkinson Disease

BACKGROUND

Awake craniotomy for tumor resection and epilepsy surgery is a well-tolerated procedure. Qualitative data on patients' experience of awake deep-brain stimulation (DBS) are, however, lacking. We collected qualitative data on patients' experience of awake DBS with a view to identifying areas for improvement.

METHODS

Forty-one patients undergoing DBS for Parkinson disease between 2009 and 2015 were surveyed with a structured questionnaire designed to receive patient feedback regarding perioperative management of the awake stage of the procedure.

RESULTS

More than 90% of patients felt well-informed. Most remembered the procedure, and almost all were happy that they did. One half of the patients experienced pain, often significant, during the procedure. This mainly occurred during burr-hole drilling and stereotactic frame placement.

CONCLUSIONS

Although awake DBS is well-tolerated, pain and off-period symptoms are an issue for a significant number of patients. Efforts should be made to minimize these unpleasant aspects of awake DBS.

Awake Craniotomy Anesthesia: A Comparison of the Monitored Anesthesia Care and Asleep-Awake-Asleep Techniques

BACKGROUND

Commonly used sedation techniques for an awake craniotomy include monitored anesthesia care (MAC), using an unprotected airway, and the asleep-awake-asleep (AAA) technique, using a partially or totally protected airway. We present a comparative analysis of the MAC and AAA techniques, evaluating anesthetic management, perioperative outcomes, and complications in a consecutive series of patients undergoing the removal of an eloquent brain lesion.

METHODS

Eighty-one patients underwent awake craniotomy for an intracranial lesion over a 9-year period performed by a single-surgeon and a team of anesthesiologists. Fifty patients were treated using the MAC technique, and 31 were treated using the AAA technique. A retrospective analysis evaluated anesthetic management, intraoperative complications, postoperative outcomes, pain management, and complications.

RESULTS

The MAC and AAA groups had similar preoperative patient and tumor characteristics. Mean operative time was shorter in the MAC group (283.5 minutes vs. 313.3 minutes; P = 0.038). Hypertension was the most common intraoperative complication seen (8% in the MAC group vs. 9.7% in the AAA group; P = 0.794). Intraoperative seizure occurred at a rate of 4% in the MAC group and 3.2% in the AAA group (P = 0.858). Awake cases were converted to general anesthesia in no patients in the MAC group and in 1 patient (3.2%) in the AAA group (P = 0.201). No cases were aborted in either group. The mean hospital length of stay was 3.98 days in the MAC group and 3.84 days in the AAA group (P = 0.833).

CONCLUSIONS

Both the MAC and AAA sedation techniques provide an efficacious and safe method for managing awake craniotomy cases and produce similar perioperative outcomes, with the MAC technique associated with shorter operative time.

Preoperative rTMS Language Mapping in Speech-Eloquent Brain Lesions Resected Under General Anesthesia: A Pair-Matched Cohort Study

OBJECTIVE

The value of preoperative repetitive transcranial magnetic stimulation (rTMS) language mapping for function preservation in surgery of speech-eloquent lesions under general anesthesia remains to be determined.

METHODS

We prospectively enrolled 20 consecutive right-handed patients with a malignant, left-sided perisylvian language-eloquent brain tumor. All patients were subjected to surgical resection under general anesthesia guided by preoperative rTMS language mapping (rTMS group, 2014-2016). A matched-pair analysis with 20 patients who also underwent surgical resection under general anesthesia in the pre-rTMS era (pre-rTMS group, 2009-2013) was performed. Language performance status was ranked from grade 0 to grade 3 (none, mild, medium, severe).

RESULTS

Rates of gross total resection, tumor residual, and complications were equal in both groups. Duration of surgery (P = 0.039) and inpatient stay (P = 0.001) were significantly shorter in the rTMS group. Preoperatively, 14 patients in the rTMS and 13 patients in the pre-rTMS group had language deficits (P = 0.380). One week after surgery, 8/14 patients (57.1%) in the rTMS group but only 1/13 patients (7.7%) in the pre-rTMS group experienced improvement of language performance status (P = 0.013). At 6 weeks follow-up, language performance status was significantly better in the rTMS group (P = 0.048). However, at 3 months follow-up, the rTMS and pre-rTMS groups showed an equal language performance status.

CONCLUSIONS

Implementation of preoperative rTMS language mapping seems to provide a favorable early language outcome in patients undergoing surgical resection of language-eloquent lesions under general anesthesia.

Endoscopic Versus Microscopic Transsphenoidal Approach for Pituitary Adenomas: Comparison of Outcomes During the Transition of Methods of a Single Surgeon

OBJECTIVE

The transition from microscopic to fully endoscopic transsphenoidal surgery requires a surgeon to assess how the change in technique will affect the extent of tumor resection (EOR), outcomes, and complications. We compared a single surgeon's experience transitioning from one technique to the other and examined the operative outcomes and EOR between microscopic versus endoscopic transsphenoidal surgery.

METHODS

Retrospective data analysis of adult patients who were treated surgically for a pituitary adenoma between August 2005 and May 2015 by a single neurosurgeon, who was originally trained and practiced in the microscopic transsphenoidal approach. Patient demographics, perioperative conditions, tumor characteristics, operative times, volumetric EOR, postoperative outcome, and the endoscopic learning curve were evaluated.

RESULTS

One hundred and nine patients underwent microscopic transsphenoidal surgery and 275 patients underwent a fully endoscopic approach. The patient characteristics were similar in the 2 groups. Operative room time was significantly shorter in the endoscopic group than in the microscopic group (180.2 vs. 215.6 minutes; P < 0.001). The endoscopic and microscopic groups had similar volumetric EOR (85.1% vs. 82.8%; P = 0.371) as well as residual tumor volume (1.06 cm³ vs. 1.15 cm³; P = 0.765). The mean length of hospital stay was 2.4 days in the endoscopic group and 3.2 days in the microscopic group (P = 0.03).

CONCLUSIONS

During the transition from the microscopic to the endoscopic approach, similar surgical outcomes and EOR were achieved in the 2 cohorts. In our experience, the endoscopic approach offers the advantage of shorter operative times and lengths of hospital stays after the surgeon has developed more experience with the technique.

Anaesthesia Management for Awake Craniotomy: Systematic Review and Meta-Analysis

BACKGROUND

Awake craniotomy (AC) renders an expanded role in functional neurosurgery. Yet, evidence for optimal anaesthesia management remains limited. We aimed to summarise the latest clinical evidence of AC anaesthesia management and explore the relationship of AC failures on the used anaesthesia techniques.

METHODS

Two authors performed independently a systematic search of English articles in PubMed and EMBASE database 1/2007-12/2015. Search included randomised controlled trials (RCTs), observational trials, and case reports (n>4 cases), which reported anaesthetic approach for AC and at least one of our pre-specified outcomes: intraoperative seizures, hypoxia, arterial hypertension, nausea and vomiting, neurological dysfunction, conversion into general anaesthesia and failure of AC. Random effects meta-analysis was used to estimate event rates for four outcomes. Relationship with anaesthesia technique was explored using logistic meta-regression, calculating the odds ratios (OR) and 95% confidence intervals [95%CI].

RESULTS

We have included forty-seven studies. Eighteen reported asleep-awake-asleep technique (SAS), twenty-seven monitored anaesthesia care (MAC), one reported both and one used the awake-awake-awake technique (AAA). Proportions of AC failures, intraoperative seizures, new neurological dysfunction and conversion into general anaesthesia (GA) were 2% [95%CI:1-3], 8% [95%CI:6-11], 17% [95%CI:12-23] and 2% [95%CI:2-3], respectively. Meta-regression of SAS and MAC technique did not reveal any relevant differences between outcomes explained by the technique, except for conversion into GA. Estimated OR comparing SAS to MAC for AC failures was 0.98 [95%CI:0.36-2.69], 1.01 [95%CI:0.52-1.88] for seizures, 1.66 [95%CI:1.35-3.70] for new neurological dysfunction and 2.17 [95%CI:1.22-3.85] for conversion into GA. The latter result has to be interpreted cautiously. It is based on one retrospective high-risk of bias study and significance was abolished in a sensitivity analysis of only prospectively conducted studies.

CONCLUSION

SAS and MAC techniques were feasible and safe, whereas data for AAA technique are limited. Large RCTs are required to prove superiority of one anaesthetic regime for AC.

Continuous physical examination during subcortical resection in awake craniotomy patients: Its usefulness and surgical outcome

OBJECTIVES

To evaluate the value of physical examination as a monitoring tool during subcortical resection in awake craniotomy patients and surgical outcomes.

PATIENTS AND METHODS

Authors reviewed medical records of patients underwent awake craniotomy with continuous physical examination for pathology adjacent to the eloquent area.

RESULTS

Between January 2006 and August 2015, there were 37 patients underwent awake craniotomy with continuous physical examination. Pathology was located in the left cerebral hemisphere in 28 patients (75.7%). Thirty patients (81.1%) had neuroepithelial tumors. Degree of resections were defined as total, subtotal, and partial in 16 (43.2%), 11 (29.7%) and 10 (27.0%) patients, respectively. Median follow up duration was 14 months. The reasons for termination of subcortical resection were divided into 3 groups as follows: 1) by anatomical landmark with the aid of neuronavigation in 20 patients (54%), 2) by reaching subcortical stimulation threshold in 8 patients (21.6%), and 3) by abnormal physical examination in 9 patients (24.3%). Among these 3 groups, there were statistically significant differences in the intraoperative (p=0.002) and early postoperative neurological deficit (p=0.005) with the lowest deficit in neuronavigation group. However, there were no differences in neurological outcome at later follow up (3-months p=0.103; 6-months p=0.285). There were no differences in the degree of resection among the groups.

CONCLUSION

Continuous physical examination has shown to be of value as an additional layer of monitoring of subcortical white matter during resection and combining several methods may help increase the efficacy of mapping and monitoring of subcortical functions.

Awake craniotomy to maximize glioma resection: methods and technical nuances over a 27-year period

OBJECT

Awake craniotomy is currently a useful surgical approach to help identify and preserve functional areas during cortical and subcortical tumor resections. Methodologies have evolved over time to maximize patient safety and minimize morbidity using this technique. The goal of this study is to analyze a single surgeon's experience and the evolving methodology of awake language and sensorimotor mapping for glioma surgery.

METHODS

The authors retrospectively studied patients undergoing awake brain tumor surgery between 1986 and 2014. Operations for the initial 248 patients (1986–1997) were completed at the University of Washington, and the subsequent surgeries in 611 patients (1997–2014) were completed at the University of California, San Francisco. Perioperative risk factors and complications were assessed using the latter 611 cases.

RESULTS

The median patient age was 42 years (range 13–84 years). Sixty percent of patients had Karnofsky Performance Status (KPS) scores of 90–100, and 40% had KPS scores less than 80. Fifty-five percent of patients underwent surgery for high-grade gliomas, 42% for low-grade gliomas, 1% for metastatic lesions, and 2% for other lesions (cortical dysplasia, encephalitis, necrosis, abscess, and hemangioma). The majority of patients were in American Society of Anesthesiologists (ASA) Class 1 or 2 (mild systemic disease); however, patients with severe systemic disease were not excluded from awake brain tumor surgery and represented 15% of study participants. Laryngeal mask airway was used in 8 patients (1%) and was most commonly used for large vascular tumors with more than 2 cm of mass effect. The most common sedation regimen was propofol plus remifentanil (54%); however, 42% of patients required an adjustment to the initial sedation regimen before skin incision due to patient intolerance. Mannitol was used in 54% of cases. Twelve percent of patients were active smokers at the time of surgery, which did not impact completion of the intraoperative mapping procedure. Stimulation-induced seizures occurred in 3% of patients and were rapidly terminated with ice-cold Ringer's solution. Preoperative seizure history and tumor location were associated with an increased incidence of stimulation-induced seizures. Mapping was aborted in 3 cases (0.5%) due to intraoperative seizures (2 cases) and patient emotional intolerance (1 case). The overall perioperative complication rate was 10%.

CONCLUSIONS

Based on the current best practice described here and developed from multiple regimens used over a 27-year period, it is concluded that awake brain tumor surgery can be safely performed with extremely low complication and failure rates regardless of ASA classification; body mass index; smoking status; psychiatric or emotional history; seizure frequency and duration; and tumor site, size, and pathology.

Awake craniotomy for supratentorial gliomas: why, when and how?

Awake craniotomy has become an increasingly utilized procedure in the treatment of supratentorial intra-axial tumors. The popularity of this procedure is partially attributable to improvements in intraoperative technology and anesthetic techniques. The application of awake craniotomy to the field of neuro-oncology has decreased iatrogenic postoperative neurological deficits, allowed for safe maximal tumor resection and improved healthcare resource stewardship by permitting early patient discharge. In this article, we review recent evidence for the utility of awake craniotomy in the resection of gliomas and describe the senior author's experience in performing this procedure. Furthermore, we explore innovative applications of awake craniotomy to outpatient tumor resections and the conduct of neurosurgery in resource-poor settings. We conclude that awake craniotomy is an effective and versatile neurosurgical procedure with expanding applications in neuro-oncology.

Drivers of hospitalization cost after craniotomy for tumor resection: creation and validation of a predictive model

Background

The economic sustainability of all areas of medicine is under scrutiny. Limited data exist on the drivers of cost after a craniotomy for tumor resection (CTR). The objective of the present study was to develop and validate a predictive model of hospitalization cost after CTR.

Methods

We performed a retrospective study involving CTR patients who were registered in the Nationwide Inpatient Sample (NIS) database from 2005–2010. This cohort underwent 1:1 randomization to create derivation and validation subsamples. Regression techniques were used for the creation of a parsimonious predictive model.

Results

Of the 36,433 patients undergoing CTR, 14638 (40.2%) underwent craniotomies for primary malignant, 9574 (26.3%) for metastatic, and 11414 (31.3%) for benign tumors. The median hospitalization cost was $24,504 (Interquartile Range (IQR), $4,265-$44,743). Common drivers of cost identified in the multivariate analyses included: length of stay, number of procedures, hospital size and region, and patient income. The models were validated in independent cohorts and demonstrated final R² very similar to the initial models. The predicted and observed values in the validation cohort demonstrated good correlation.

Conclusions

This national study identified significant drivers of hospitalization cost after CTR. The presented model can be utilized as an adjunct in the cost containment debate and the creation of data-driven policies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-015-0742-2) contains supplementary material, which is available to authorized users.

Comparison of outcomes in patients undergoing percutaneous renal cryoablation with sedation vs general anesthesia

OBJECTIVE

To compare the efficacy and safety of local anesthesia with conscious sedation (LACS) with general anesthesia (GA) in patients undergoing percutaneous renal cryoablation (PRC) for renal cortical neoplasms.

METHODS

We performed a retrospective review of patients undergoing PRC between 2003 and 2013. Patient demographics, tumor characteristics, and perioperative and postoperative follow-up data were recorded and analyzed. We compared 3 principal outcomes across the GA and LACS groups: anesthesia-related outcomes, treatment failure, and complications.

RESULTS

A total of 235 patients with available data were included. Of these, 82 underwent PRC under GA and 153 patients under LACS. The 2 groups were similar with regard to age, gender, body mass index, American Society of Anesthesiologists score, tumor features, preoperative serum creatinine level, and hematocrit value. The GA and LACS groups had a similar percentage of patients with biopsy-proven renal cell carcinoma (68.5% and 64.2%, respectively; P = .62). The mean follow-up time for GA and LACS was 37 and 21 months, respectively (P <.0001). The mean procedure time for GA was significantly longer compared with LACS (133 vs 102 minutes; P <.001), and the mean hospital stay was shorter under LACS (1.08 vs 1.95 days; P <.0001). There was no difference in immediate failure (0% and 1.9%; P = .051) or recurrences (11% and 3.9%, respectively; P = .051) between GA and LACS groups. There was no difference in intraoperative and postoperative treatment-related complications between the 2 groups.

CONCLUSION

PRC for small renal masses under LACS is effective and safe. PRC with LACS has the advantage of decreased procedure time and a shorter hospital stay.

Patient response to awake craniotomy - a summary overview

BACKGROUND

Awake craniotomy is a valuable procedure since it allows brain mapping and live monitoring of eloquent brain functions. The advantage of minimizing resource utilization is also emphasized by some physicians in North America. Data on how well an awake craniotomy is tolerated by patients and how much stress it creates is available from different studies, but this topic has not consequently been summarized in a review of the available literature. Therefore, it is the purpose of this review to shed more light on the still controversially discussed aspect of an awake craniotomy.

METHODS

We reviewed the available English literature published until December 2013 searching for studies that investigated patients' responses to awake craniotomies.

RESULTS

Twelve studies, published between 1998 and 2013, including 396 patients with awake surgery were identified. Eleven of these 12 studies set the focus on the perioperative time, one study focused on the later postoperative time. The vast majority of patients felt well prepared and overall satisfaction with the procedure was high. In the majority of studies up to 30 % of the patients recalled considerable pain and 10-14 % experienced strong anxiety during the procedure. The majority of patients reported that they would undergo an awake craniotomy again. A post traumatic stress disorder was present neither shortly nor years after surgery. However, a normal human response to such an exceptional situation can for instance be the delayed appearance of unintentional distressing recollections of the event despite the patients' satisfaction concerning the procedure.

CONCLUSIONS

For selected patients, an awake craniotomy presents the best possible way to reduce the risk of surgery related neurological deficits. However, benefits and burdens of this type of procedure should be carefully considered when planning an awake craniotomy and the decision should serve the interests of the patient.

Intraoperative monitoring of an aspect of executive functions: administration of the Stroop test in 9 adult patients during awake surgery for resection of frontal glioma

BACKGROUND

Awake brain surgery allows extensive intraoperative monitoring of not only motor and sensory functions and language but also executive functions.

OBJECTIVE

To administer the Stroop test intraoperatively to avoid dramatic side effects such as akinetic mutism and to monitor executive functions in an attempt to optimize the benefit/risk balance of surgery.

METHODS

A series of 9 adult patients with frontal glioma were operated on for gross tumor resection under local anesthesia. All procedures involved the anterior cingulate cortex (ACC).

RESULTS

Three types of response to the Stroop test were observed: 3 patients had a Stroop effect only for stimulation of the contralateral ACC; 3 patients had a Stroop effect for stimulation of the ipsilateral ACC; and 3 patients had no Stroop effect. Preoperative and postoperative neuropsychological and surgical results are presented and discussed. Stimulation sites eliciting a Stroop effect are compared with published image-based data, and insight provided by these surgical data regarding ACC function and plasticity is discussed. No operative complication related to intraoperative administration of the Stroop test was observed.

CONCLUSION

Administration of the Stroop test during resection of gliomas involving the ACC in adult patients is an option for intraoperative monitoring of executive functions during awake surgery. Globally, these results suggest functional compensation, mediated by plasticity mechanisms, by contralateral homologous regions of the ACC in adult patients with frontal glioma.