Designing Enhanced Recovery After Surgery Protocols in Neurosurgery: A Contemporary Narrative Review

Enhanced Recovery After Surgery (ERAS) protocols have revolutionized the approach to perioperative care in various surgical specialties. They reduce complications, improve patient outcomes, and shorten hospital lengths of stay. Implementation of ERAS protocols for neurosurgical procedures has been relatively underexplored and underutilized due to the unique challenges and complexities of neurosurgery. This narrative review explores the barriers to, and pioneering strategies of, standardized procedure-specific ERAS protocols, and the importance of multidisciplinary collaboration in neurosurgery and neuroanesthsia, patient-centered approaches, and continuous quality improvement initiatives, to achieve better patient outcomes. It also discusses initiatives to guide future clinical practice, research, and guideline creation, to foster the development of tailored ERAS protocols in neurosurgery.

Challenges and Opportunities in Awake Craniotomy for Brain Tumor Surgery in Low- and Lower-Middle-Income Countries: A Narrative Review and Perspective

BACKGROUND

Low-income countries (LICs) and lower-middle-income countries (LMICs) are presented with unique challenges and opportunities when performing awake craniotomy (AC) for brain tumors. These circumstances arise from factors that are financial, infrastructural, educational, personnel, and sociocultural in nature.

METHODS

We performed a systematic narrative review of series on AC for intra-axial brain tumors in LICs/LMICs using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, focusing on the challenges and opportunities in these settings. The PubMed, Scopus, and Web of Science databases were searched.

RESULTS

After initially identifying 74 studies, inclusion-exclusion criteria were applied, leaving a total of 14 studies included in the review. These involved 409 patients who underwent AC in LICs/LMICs. These series were from India, Ghana, Nigeria, Iran, Pakistan, Morocco, the Philippines, and Egypt. The most common pathology encountered were gliomas (10-70%). Most studies (11/14, 78.5%) reported on their technique of cortical-subcortical mapping. All reported on motor mapping and 8 of these performed language mapping. The most common outcomes reported were seizure and neurologic deficits, and longest follow-up was at 1 year. Challenges noted were lack of equipment and trained personnel, need for validated tests for the local setting, and sociocultural factors. Opportunities identified were volume for training, technique innovation, and international collaboration.

CONCLUSIONS

There are numerous challenges and opportunities that arise when performing AC in LICs/LMICs. A collaborative approach toward harnessing the opportunities, and seeking creative solutions to address the challenges, would provide an ideal mechanism toward advancing neurosurgical care and specialty worldwide.

Experience in awake glioma surgery in a South American center. Correlation between intraoperative evaluation, extent of resection and functional outcomes

Introduction

Gliomas are the second most frequent primary brain tumors. Surgical resection remains a crucial part of treatment, as well as maximum preservation of neurological function. For this reason awake surgery has an important role.The objectives of this article are to present our experience with awake surgery for gliomas in a South American center and to analyze how intraoperative functional findings may influence the extent of resection and neurological outcomes.

Materials and methods

Retrospective single center study of a cohort of adult patients undergoing awake surgery for brain glioma, by the same neurosurgeon, between 2012 and 2022 in the city of Buenos Aires, Argentina.

Results

A total of 71 patients were included (mean age 34 years, 62% males). Seventy seven percent of tumors were low grade, with average extent of resection reaching 94% of preoperative volumetric assessment. At six months follow up, 81.7% of patients presented no motor or language deficit.Further analysis showed that having a positive mapping did not have a negative impact in the extent of resection, but was associated with short term postoperative motor and language deficits, among other variables, with later improvement.

Conclusion

Awake surgery for gliomas is a safe procedure, with the proper training. In this study it was observed that guiding the resection by negative mapping did not worsen the results and that positive subcortical mapping correlated with short term postoperative neurological deficits with posterior improvement within six months in most cases.

Awake craniotomies in South America: Advancements, challenges, and future prospects

BACKGROUND: Awake craniotomy has emerged as an advanced surgical technique, characterized by keeping the patient awake during brain surgery. In South America, awake craniotomies have grained traction in neurosurgical practices across various medical centres and hospitals, with notable practitioners contributing to its growth and refinement in the region. PURPOSE: This study aims to explore the integration and impact of awake craniotomies in South American neurosurgical practices. The focus is on understanding the benefits, challenges, and potential transformative effects of the procedure in the region. RESEARCH DESIGN: A comprehensive narrative review and analysis through a thorough examination of the existing literature. RESULTS: The findings indicate that awake craniotomies in South America offer substantial benefits, including cost savings thorugh reduced hospitalization time, quicker recovery and decreased morbidity. Enhanced safety, effective pain management and reduced anaesthesia also contribute to this. CONCLUSION: Whilst the adaptation of awake craniotomies in South America holds great promise in transforming neurosurgical care in the region, significant challenges hinder its widespread adoption. Inadequate infrastructure, limited access to equipment, financial instability, and shortages in trained healthcare providers represent challenges that need to be addressed.

Awake Craniotomy Program Implementation

Importance

Implementing multidisciplinary teams for treatment of complex brain tumors needing awake craniotomies is associated with significant costs. To date, there is a paucity of analysis on the cost utility of introducing advanced multidisciplinary standardized teams to enable awake craniotomies.

Objective

To assess the cost utility of introducing a standardized program of awake craniotomies.

Design, Setting, and Participants

A retrospective economic evaluation was conducted at Mayo Clinic Florida. All patients with single, unilateral lesions who underwent elective awake craniotomies between January 2016 and December 2021 were considered eligible for inclusion. The economic perspective of the health care institution and a time horizon of 1 year were considered. Data were analyzed from October 2022 to May 2023.

Exposure

Treatment with an awake craniotomy before standardization (2016-2018) compared with treatment with awake craniotomy after standardization (2018-2021).

Main Outcomes and Measures

Patient demographics, perioperative, and postoperative outcomes, including length of stay, intensive care (ICU) admission, extent of resection, readmission rates, and 1-year mortality were compared between patients undergoing surgery before and after standardization. Direct medical costs were estimated from Medicare reimbursement rates for all billed procedures. A cost-utility analysis was performed considering differences in direct medical costs and in 1-year mortality within the periods before and after standardization of procedures. Uncertainty was explored in probability sensitivity analysis.

Results

A total of 164 patients (mean [SD] age, 49.9 [15.7] years; 98 [60%] male patients) were included in the study. Of those, 56 underwent surgery before and 108 after implementation of procedure standardization. Procedure standardization was associated with reductions in length of stay from a mean (SD) of 3.34 (1.79) to 2.46 (1.61) days (difference, 0.88 days; 95% CI, 0.33-1.42 days; P = .002), length of stay in ICU from a mean (SD) of 1.32 (0.69) to 0.99 (0.90) nights (difference, 0.33 nights; 95% CI, 0.06-0.60 nights; P = .02), 30-day readmission rate from 14% (8 patients) in the prestandardization cohort to 5% (5 patients) (difference, 9%; 95% CI, 19.6%-0.3%; P = .03), while extent of resection and intraoperative complication rates were similar between both cohorts. The standardized protocol was associated with mean (SD) savings of $7088.80 ($12 389.50) and decreases in 1-year mortality (dominant intervention). This protocol was found to be cost saving in 75.5% of all simulations in probability sensitivity analysis.

Conclusions and Relevance

In this economic evaluation of standardization of awake craniotomy, there was a generalized reduction in length of stay, ICU admission time, and direct medical costs with implementation of an optimized protocol. This was achieved without compromising patient outcomes and with similar extent of resection, complication rates, and reduced readmission rates.

The state of art of awake craniotomy in Latin American countries: a scoping review

BACKGROUND AND OBJECTIVE

Awake craniotomy (AC) is a valuable technique for surgical interventions in eloquent areas, but its adoption in low- and middle-income countries faces challenges like limited infrastructure, trained personnel shortage, and inadequate funding. This scoping review explores AC techniques in Latin American countries, focusing on patient characteristics, tumor location, symptomatology, and outcomes.

METHODS

A scoping review followed PRISMA guidelines, searching five databases in English, Spanish, and Portuguese. We included 28 studies with 258 patients (mean age: 43, range: 11-92). Patterns in AC use in Latin America were analyzed.

RESULTS

Most studies were from Brazil and Mexico (53.6%) and public institutions (70%). Low-grade gliomas were the most common lesions (55%), most of them located in the left hemisphere (52.3%) and frontal lobe (52.3%). Gross-total resection was achieved in 34.3% of cases. 62.9% used an Asleep-Awake-Asleep protocol, and 14.8% used Awake-Awake-Awake. The main complication was seizures (14.6%). Mean post-surgery discharge time was 68 h. Challenges included limited training, infrastructure, and instrumentation availability. Strategies discussed involve training in specialized centers, seeking sponsorships, applying for awards, and multidisciplinary collaborations with neuropsychology.

CONCLUSION

Improved accessibility to resources, infrastructure, and adequate instrumentation is crucial for wider AC availability in Latin America. Despite disparities, AC implementation with proper training and teamwork yields favorable outcomes in resource-limited centers. Efforts should focus on addressing challenges and promoting equitable access to this valuable surgical technique in the region.

The Hitchhiker's Guide to Spine Awake Surgery. The Oxford SAS Protocol and Early Outcomes

OBJECTIVE

Spine awake surgery (SAS) aims to achieve faster recovery times, better outcomes, and a lesser economic impact on society. Our drive to establish SAS was to improve patient outcomes and health economics during the COVID-19 pandemic. After a systematic review and to the best of our knowledge, SAS, the Oxford Protocol, is the first protocolized pathway that aims to train bespoke teams performing SAS safely, efficiently, and in a standardized repeatable fashion. A pilot study was designed around newly derived protocols and simulated training to determine if SAS is a safe and implementable pathway to improve patient outcomes and health economics.

METHODS

We assessed a cohort of 10 patients undergoing one-level lumbar discectomies and decompressions, analyzing the related costs, length of stay, complications, pain management, and patient satisfaction.

RESULTS

The age range of our patients was 46-84 years. Three discectomies and 7 central canal stenosis decompressions were performed. Eight patients were discharged on the same day. All patients gave positive feedback about their experience of SAS. A significant cost saving was made compared to a general anesthesia (GA) overnight stay across the group. No on day cancellations occurred due to lack of bed availability. No patient needed analgesia in the recovery room or needed additional analgesia over and above the SAS e-prescription take home package.

CONCLUSIONS

Our early experience and journey reinforce our drive to push forward and expand on this process. It aligns with the international literature which highlights this approach as safe, efficient, and economical.

Anesthetic Management for Awake Craniotomy Applied to Neurosurgery

Our anesthetic technique proposed for awake craniotomy is the monitored anesthesia care (MAC) technique, with the patient in sedation throughout the intervention. Our protocol involves analgo-sedation through the administration of dexmedetomidine and remifentanil in a continuous intravenous infusion, allowing the patient to be sedated and in comfort, but contactable and spontaneously breathing. Pre-surgery, the patient is pre-medicated with intramuscular clonidine (2 µg/kg); it acts both as an anxiolytic and as an adjuvant in pain management and improves hemodynamic stability. In the operating setting, dexmedetomidine in infusion and remifentanil in target controlled infusion (TCI) for effect are started. The purpose of the association is to exploit the pharmacodynamics of dexmedetomidine which guarantees the control of respiratory drive, and the pharmacokinetics of remifentanil characterized by insensitivity to the drug. Post-operative management: at the end of the surgical procedure, the infusion of drugs was suspended. Wake-up craniotomy is associated with reduced hospital costs compared to craniotomy performed in general anesthesia, mainly due to reduced costs in the operating room and shorter hospital stays. Greater patient satisfaction and the benefits of avoiding hospital stay have led to the evolution of outpatient intracranial neurosurgery.

Surgical Outcomes of Awake Craniotomy for Treatment of Arteriovenous Malformations in Eloquent Cortex: A Systematic Review

OBJECTIVE

Arteriovenous malformations (AVMs) located in eloquent brain regions are historically associated with a poor prognosis. Awake craniotomy (AC) with the adjunct of brain mapping has the potential of identifying non-eloquent gyri to maximize resection, thereby theoretically decreasing the risk of neurologic deficits. With limited evidence regarding the efficacy of AC in treatment of eloquent AVMs, this review aims to investigate its surgical outcomes.

METHODS

A systematic search in the PubMed database was performed to identify all relevant studies up to February 2022.

RESULTS

A total of 13 studies were extracted for quantitative analysis, yielding a total of 46 patients. The mean age was 34.1 years, and most patients were female (54.8%). Seizures were the most frequently reported presenting symptom (41%, 19 of 46 cases). Spetzler-Martin Grade III was the most prevalent (45.9%, 17 cases) with a mean nidus size of 32.6 mm. Seventy-four percent of AVMs were located on the left side, with the frontal lobe being the most common location (30%, 14 of 46 cases). The most common eloquent regions were language (47.8%, 22 of 46 cases), motor (17.4%, 8 of 46 cases), and language + motor cortices (13.1%, 6 of 46 cases). Complete resection of AVM was achieved in 41 patients (89%). Intraoperative complications occurred in 14 of 46 cases (30.4%) with transient postoperative neurologic deficits in 14 patients (30.4%).

CONCLUSIONS

AC may enable precise microsurgical excision of eloquent AVMs with preservation of critical brain functions. Risk factors for poor outcomes include eloquent AVMs located in the language + motor regions and the occurrence of intraoperative complications such as seizures/hemorrhage.

Predictors of extended length of stay related to craniotomy for tumor resection

Background

Hospital length of stay (LOS) related to craniotomy for tumor resection (CTR) is a marker of neurosurgical quality of care. Limiting LOS benefits both patients and hospitals. This study examined which factors contribute to extended LOS (eLOS) at our academic center.

Methods

Retrospective medical record review of 139 consecutive CTRs performed between July 2020 and July 2021. Univariate and multivariable analyses determined which factors were associated with an eLOS (≥8 days).

Results

Median LOS was 6 days (IQR 3-9 days). Fifty-one subjects (36.7%) experienced an eLOS. Upon univariate analysis, potentially modifiable factors associated with eLOS included days to occupational therapy (OT), physical therapy (PT), and case management clearance (p < .001); and discharge disposition (p < .001). Multivariable analysis revealed that pre-operative anti-coagulant use (OR 10.74, 95% CI 2.64-43.63, p = .001), Medicare (OR 4.80, 95% CI 1.07-21.52, p = .04), ED admission (OR 26.21, 95% CI 5.17-132.99, p < .001), transfer to another service post-surgery (OR 30.00, 95% CI 1.56-577.35, p = .02), and time to post-operative imaging (OR 2.91, 95% CI 1.27-6.65, p = .01) were associated with eLOS. Extended LOS was not significantly associated with ED visits (p = .45) or unplanned readmissions within 30 days of surgery (p = .35), and both (p = .04; p = .04) were less likely following a short LOS (<5 days).

Conclusion

While some factors driving LOS related to CTR are uncontrollable, expedient pre- and post-operative management may reduce LOS without compromising care.

Monitored anesthesia care and asleep-awake-asleep techniques combined with multiple monitoring for resection of gliomas in eloquent brain areas: a retrospective analysis of 225 patients

BACKGROUND

Awake craniotomy (AC) has become gold standard in surgical resection of gliomas located in eloquent areas. The conscious sedation techniques in AC include both monitored anesthesia care (MAC) and asleep-awake-asleep (AAA). The choice of optimal anesthetic method depends on the preferences of the surgical team (mainly anesthesiologist and neurosurgeon). The aim of this study was to compare the difference in physiological and blood gas data, dosage of different drugs, the probability of switching to endotracheal intubation, and extent of tumor resection and dysfunction after operation between AAA and MAC anesthetic management for resection of gliomas in eloquent brain areas.

METHODS

Two-hundred and twenty-five patients with super-tentorial tumor located in eloquent areas underwent AC from 2009 to 2021 in Xijing Hospital. Forty-one patients underwent AAA technique, and the rest one-hundred eighty-four patients underwent MAC technique. Anesthetic management, dosage of different drugs, intraoperative complications, postoperative outcomes, adverse events, extent of resection and motor, and sensory and language dysfunction after operation were compared between MAC and AAA.

RESULT

There was no significant difference in gender, KPS score, MMSE score, glioma grade, type, and growth site between the patients in the two groups, except the older age of patients in MAC group than that in AAA group. During the whole process of operation, there were greater pulse pressure difference (P = 0.046), shorter operation time (P = 0.039), less dosage of remifentanil (P = 0.000), more dosage of dexmedetomidine (P = 0.013), more use of antiemetics (81%, P = 0.0067), lower use of vasoactive agent (45.1%, P = 0.010), and lower probability of conversion to general anesthesia (GA, P = 0.027) in MAC group than that in AAA group. Blood gas analysis showed that PetCO2 (P = 0.000), Glu concentration (P = 0.000), and PaCO2 (P = 0.000) were higher, but SPO2 (P = 0.002) and PaO2 (P = 0.000) were lower in MAC group than that in AAA group. In the postoperative recovery stage, compared with that of AAA group, the probability of dysfunction in MAC group at 1, 3, 5, and 7 days after operation was lower, which were 27.8% vs 53.6% (P = 0.003), 31% vs 68.3% (P = 0.000), 28.8% vs 63.4% (P = 0.000), and 25.6% vs 58.5% (P = 0.000), respectively.

CONCLUSION

Compared with AAA, it seems that MAC has more advantages in the management for resection of gliomas in eloquent brain areas, and MAC combined with multiple monitoring such as cerebral cortical mapping, neuronavigation, and ultrasonic detection is worthy of popularization for the resection of gliomas in eloquent brain areas.

An economic study of neuro-oncological patients in a large developing country: a cost analysis

BACKGROUND

Neuro-oncological patients require specialized medical care. However, the data on the costs incurred for such specialized care in developing countries are currently lacking. These data are relevant for international cooperation.

OBJECTIVE

The present study aimed to estimate the direct cost of specialized care for an adult neuro-oncological patient with meningioma or glioma during hospitalization in the largest philanthropic hospital in Latin America.

METHODS

The present observational economic analysis describes the direct cost of care of neuro-oncological patients in Santa Casa de São Paulo, Brazil. Only adult patients with a common primary brain tumor were included.

RESULTS

Due to differences in the system records, the period analyzed for cost estimation was between December 2016 and December 2019. A group of patients with meningiomas and gliomas was analyzed. The estimated mean cost of neurosurgical hospitalization was US$4,166. The cost of the operating room and intensive care unit represented the largest proportion of the total cost. A total of 17.5% of patients had some type of infection, and 66.67% of these occurred in nonelective procedures. The mortality rate was 12.7% and 92.3% of all deaths occurred in emergency procedures.

CONCLUSIONS

Emergency surgeries were associated with an increased rate of infections and mortality. The findings of the present study could be used by policymakers for resource allocation and to perform economic analyses to establish the value of neurosurgery in achieving global health goals.

Surgical Treatment of Glioblastoma: State-of-the-Art and Future Trends

Glioblastoma (GBM) is a highly aggressive disease and is associated with poor prognosis despite treatment advances in recent years. Surgical resection of tumor remains the main therapeutic option when approaching these patients, especially when combined with adjuvant radiochemotherapy. In the present study, we conducted a comprehensive literature review on the state-of-the-art and future trends of the surgical treatment of GBM, emphasizing topics that have been the object of recent study.

IDH-wild-type glioblastoma cell density and infiltration distribution influence on supramarginal resection and its impact on overall survival: a mathematical model

OBJECTIVE

Recent studies have proposed resection of the T2 FLAIR hyperintensity beyond the T1 contrast enhancement (supramarginal resection [SMR]) for IDH-wild-type glioblastoma (GBM) to further improve patients' overall survival (OS). GBMs have significant variability in tumor cell density, distribution, and infiltration. Advanced mathematical models based on patient-specific radiographic features have provided new insights into GBM growth kinetics on two important parameters of tumor aggressiveness: proliferation rate (ρ) and diffusion rate (D). The aim of this study was to investigate OS of patients with IDH-wild-type GBM who underwent SMR based on a mathematical model of cell distribution and infiltration profile (tumor invasiveness profile).

METHODS

Volumetric measurements were obtained from the selected regions of interest from pre- and postoperative MRI studies of included patients. The tumor invasiveness profile (proliferation/diffusion [ρ/D] ratio) was calculated using the following formula: ρ/D ratio = (4π/3)2/3 × (6.106/[VT21/1 - VT11/1])2, where VT2 and VT1 are the preoperative FLAIR and contrast-enhancing volumes, respectively. Patients were split into subgroups based on their tumor invasiveness profiles. In this analysis, tumors were classified as nodular, moderately diffuse, or highly diffuse.

RESULTS

A total of 101 patients were included. Tumors were classified as nodular (n = 34), moderately diffuse (n = 34), and highly diffuse (n = 33). On multivariate analysis, increasing SMR had a significant positive correlation with OS for moderately and highly diffuse tumors (HR 0.99, 95% CI 0.98-0.99; p = 0.02; and HR 0.98, 95% CI 0.96-0.99; p = 0.04, respectively). On threshold analysis, OS benefit was seen with SMR from 10% to 29%, 10% to 59%, and 30% to 90%, for nodular, moderately diffuse, and highly diffuse, respectively.

CONCLUSIONS

The impact of SMR on OS for patients with IDH-wild-type GBM is influenced by the degree of tumor invasiveness. The authors' results show that increasing SMR is associated with increased OS in patients with moderate and highly diffuse IDH-wild-type GBMs. When grouping SMR into 10% intervals, this benefit was seen for all tumor subgroups, although for nodular tumors, the maximum beneficial SMR percentage was considerably lower than in moderate and highly diffuse tumors.

Predictors for time to awake in patients undergoing awake craniotomies

OBJECTIVE

Awake craniotomies are often characterized by alternating asleep-awake-asleep periods. Preceding the awake phase, patients are weaned from anesthesia and mechanical ventilation. Although clinicians aim to minimize the time to awake for patient safety and operating room efficiency, in some patients, the time to awake exceeds 20 minutes. The goal of this study was to determine the average time to awake and the factors associated with prolonged time to awake (> 20 minutes) in patients undergoing awake craniotomy.

METHODS

Records of patients who underwent awake craniotomy between 2003 and 2020 were evaluated. Time to awake was defined as the time between discontinuation of propofol and remifentanil infusion and the time of extubation. Patient and perioperative characteristics were explored as predictors for time to awake using logistic regression analyses.

RESULTS

Data of 307 patients were analyzed. The median (IQR) time to awake was 13 (10-20) minutes and exceeded 20 minutes in 17% (95% CI 13%-21%) of the patients. In both univariate and multivariable analyses, increased age, nonsmoker status, and American Society of Anesthesiologists (ASA) class III versus II were associated with a time to awake exceeding 20 minutes. BMI, as well as the use of alcohol, drugs, dexamethasone, or antiepileptic agents, was not significantly associated with the time to awake.

CONCLUSIONS

While most patients undergoing awake craniotomy are awake within a reasonable time frame after discontinuation of propofol and remifentanil infusion, time to awake exceeded 20 minutes in 17% of the patients. Increasing age, nonsmoker status, and higher ASA classification were found to be associated with a prolonged time to awake.

Influence of supramarginal resection on survival outcomes after gross-total resection of IDH-wild-type glioblastoma

OBJECTIVE

The authors' goal was to use a multicenter, observational cohort study to determine whether supramarginal resection (SMR) of FLAIR-hyperintense tumor beyond the contrast-enhanced (CE) area influences the overall survival (OS) of patients with isocitrate dehydrogenase-wild-type (IDH-wt) glioblastoma after gross-total resection (GTR).

METHODS

The medical records of 888 patients aged ≥ 18 years who underwent resection of GBM between January 2011 and December 2017 were reviewed. Volumetric measurements of the CE tumor and surrounding FLAIR-hyperintense tumor were performed, clinical variables were obtained, and associations with OS were analyzed.

RESULTS

In total, 101 patients with newly diagnosed IDH-wt GBM who underwent GTR of the CE tumor met the inclusion criteria. In multivariate analysis, age ≥ 65 years (HR 1.97; 95% CI 1.01-2.56; p < 0.001) and contact with the lateral ventricles (HR 1.59; 95% CI 1.13-1.78; p = 0.025) were associated with shorter OS, but preoperative Karnofsky Performance Status ≥ 70 (HR 0.47; 95% CI 0.27-0.89; p = 0.006), MGMT promotor methylation (HR 0.63; 95% CI 0.52-0.99; p = 0.044), and increased percentage of SMR (HR 0.99; 95% CI 0.98-0.99; p = 0.02) were associated with longer OS. Finally, 20% SMR was the minimum percentage associated with beneficial OS (HR 0.56; 95% CI 0.35-0.89; p = 0.01), but > 60% SMR had no significant influence (HR 0.74; 95% CI 0.45-1.21; p = 0.234).

CONCLUSIONS

SMR is associated with improved OS in patients with IDH-wt GBM who undergo GTR of CE tumor. At least 20% SMR of the CE tumor was associated with beneficial OS, but greater than 60% SMR had no significant influence on OS.

Functional Outcomes and Health-Related Quality of Life Following Glioma Surgery

Functional outcome following glioma surgery is defined as how the patient functions or feels. Functional outcome is a coprimary end point of surgery in patients with diffuse glioma, together with oncological outcome. In this review, we structure the functional outcome measurements following glioma surgery as reported in the last 5 yr. We review various perspectives on functional outcome of glioma surgery with available measures, and offer suggestions for their use. From the recent neurosurgical literature, 160 publications were retrieved fulfilling the selection criteria. In these publications, neurological outcomes were reported most often, followed by activities of daily living, seizure outcomes, neurocognitive outcomes, and health-related quality of life or well-being. In more than a quarter of these publications functional outcome was not reported. A minimum essential consensus set of functional outcome measurements would benefit comparison across neurosurgical reports. The consensus set should be based on a combination of clinician- and patient-reported outcomes, assessed at a predefined time before and after surgery. The selected measurements should have psychometric properties supporting the intended use including validity-related evidence, reliability, and sensitivity to detect meaningful change with minimal burden to ensure compliance. We circulate a short survey as a start towards reporting guidelines. Many questions remain to better understand, report, and improve functional outcome following glioma surgery.

Predicting Postoperative Outcomes in Brain Tumor Patients With a 5-Factor Modified Frailty Index

BACKGROUND

Frailty indices may represent useful decision support tools to optimize modifiable drivers of quality and cost in neurosurgical care. However, classic indices are cumbersome to calculate and frequently require unavailable data. Recently, a more lean 5-factor modified frailty index (mFI-5) was introduced, but it has not yet been rigorously applied to brain tumor patients.

OBJECTIVE

To investigate the predictive value of the mFI-5 on length of stay (LOS), complications, and charges in surgical brain tumor patients.

METHODS

We retrospectively reviewed data for brain tumor patients who underwent primary surgery from 2017 to 2018. Bivariate (ANOVA) and multivariate (logistic and linear regression) analyses assessed the predictive power of the mFI-5 on postoperative outcomes.

RESULTS

Our cohort included 1692 patients with a mean age of 55.5 yr and mFI-5 of 0.80. Mean intensive care unit (ICU) and total LOS were 1.69 and 5.24 d, respectively. Mean pulmonary embolism (PE)/deep vein thrombosis (DVT), physiological/metabolic derangement, respiratory failure, and sepsis rates were 7.2%, 1.1%, 1.6%, and 1.7%, respectively. Mean total charges were $42 331. On multivariate analysis, each additional point on the mFI-5 was associated with a 0.32- and 1.38-d increase in ICU and total LOS, respectively; increased odds of PE/DVT (odds ratio (OR): 1.50), physiological/metabolic derangement (OR: 3.66), respiratory failure (OR: 1.55), and sepsis (OR: 2.12); and an increase in total charges of $5846.

CONCLUSION

The mFI-5 is a pragmatic and actionable tool which predicts LOS, complications, and charges in brain tumor patients. It may guide future efforts to risk-stratify patients with subsequent impact on postoperative outcomes.

Challenges and Perspectives of Standard Therapy and Drug Development in High-Grade Gliomas

Despite their low incidence rate globally, high-grade gliomas (HGG) remain a fatal primary brain tumor. The recommended therapy often is incapable of resecting the tumor entirely and exclusively targeting the tumor leads to tumor recurrence and dismal prognosis. Additionally, many HGG patients are not well suited for standard therapy and instead, subjected to a palliative approach. HGG tumors are highly infiltrative and the complex tumor microenvironment as well as high tumor heterogeneity often poses the main challenges towards the standard treatment. Therefore, a one-fit-approach may not be suitable for HGG management. Thus, a multimodal approach of standard therapy with immunotherapy, nanomedicine, repurposing of older drugs, use of phytochemicals, and precision medicine may be more advantageous than a single treatment model. This multimodal approach considers the environmental and genetic factors which could affect the patient's response to therapy, thus improving their outcome. This review discusses the current views and advances in potential HGG therapeutic approaches and, aims to bridge the existing knowledge gap that will assist in overcoming challenges in HGG.

Awake Craniotomy in Low-Resource Settings: Findings from a Retrospective Cohort in the Philippines

BACKGROUND

Awake craniotomy is a technique used to maximize resection of lesions in eloquent areas of the brain and preserve function. Although its use in high-income centers is well documented for tumors and vascular lesions, reports of its use in low-middle-income countries are limited. There are no published series from the Philippines.

METHODS

We performed a retrospective review of all patients who underwent awake craniotomy at a tertiary referral center in Manila, Philippines from 2010 to 2019. Data on demographics, clinical features, diagnoses, intraoperative and postoperative complications, and outcomes were collected. Regression analyses were performed to correlate use of intraoperative adjuncts with outcome measures (extent of resection, complication rate, neurologic status after surgery and on last follow-up, and in-hospital mortality).

RESULTS

A total of 65 patients were included in the cohort, who had a male predilection (60%) and a mean age at diagnosis of 40.4 years. The most common indication was tumor excision (90%), followed by excision of arteriovenous malformations (5%) and cavernomas (3%). Of the tumors, the most common histopathologic diagnosis was low-grade glioma (48%). The intraoperative complication rate was 13.8%, with the most common complication being patient intolerance. Gross total excision rate for tumors was 78.3%. Univariate analysis showed that use of a cortical stimulator was associated with improved neurologic status on last follow-up (P = 0.0471).

CONCLUSIONS

Our experience shows that awake craniotomy is feasible in low-middle-income country settings and is safe and effective for excision of tumors, arteriovenous malformations, and cavernomas.

A Systematic Review of Methods Used for Confounding Adjustment in Observational Economic Evaluations in Cardiology Conducted between 2013 and 2017

Background. Observational economic evaluations (i.e., economic evaluations in which treatment allocation is not randomized) are prone to confounding bias. Prior reviews published in 2013 have shown that adjusting for confounding is poorly done, if done at all. Although these reviews raised awareness on the issues, it is unclear if their results improved the methodological quality of future work. We therefore aimed to investigate whether and how confounding was accounted for in recently published observational economic evaluations in the field of cardiology. Methods. We performed a systematic review of PubMed, Embase, Cochrane Library, Web of Science, and PsycInfo databases using a set of Medical Subject Headings and keywords covering topics in "observational economic evaluations in health within humans" and "cardiovascular diseases." Any study published in either English or French between January 1, 2013, and December 31, 2017, addressing our search criteria was eligible for inclusion in our review. Our protocol was registered with PROSPERO (CRD42018112391). Results. Forty-two (0.6%) out of 7523 unique citations met our inclusion criteria. Fewer than half of the selected studies adjusted for confounding (n = 19 [45.2%]). Of those that adjusted for confounding, propensity score matching (n = 8 [42.1%]) and other matching-based approaches were favored (n = 8 [42.1%]). Our results also highlighted that most authors who adjusted for confounding rarely justified their methodological choices. Conclusion. Our results indicate that adjustment for confounding is often ignored when conducting an observational economic evaluation. Continued knowledge translation efforts aimed at improving researchers' knowledge regarding confounding bias and methods aimed at addressing this issue are required and should be supported by journal editors.

Insurance type impacts the economic burden and survival of patients with newly diagnosed glioblastoma

OBJECTIVE

Glioblastoma (GBM) carries a high economic burden for patients and caregivers, much of which is associated with initial surgery. The authors investigated the impact of insurance status on the inpatient hospital costs of surgery for patients with GBM.

METHODS

The authors conducted a retrospective review of patients with GBM (2010-2015) undergoing their first resection at the University of California, San Francisco, and corresponding inpatient hospital costs.

RESULTS

Of 227 patients with GBM (median age 62 years, 37.9% females), 31 (13.7%) had Medicaid, 94 (41.4%) had Medicare, and 102 (44.9%) had private insurance. Medicaid patients had 30% higher overall hospital costs for surgery compared to non-Medicaid patients ($50,285 vs $38,779, p = 0.01). Medicaid patients had higher intensive care unit (ICU; p < 0.01), operating room (p < 0.03), imaging (p < 0.001), room and board (p < 0001), and pharmacy (p < 0.02) costs versus non-Medicaid patients. Medicaid patients had significantly longer overall and ICU lengths of stay (6.9 and 2.6 days) versus Medicare (4.0 and 1.5 days) and privately insured patients (3.9 and 1.8 days, p < 0.01). Medicaid patients had similar comorbidity rates to Medicare patients (67.8% vs 68.1%), and both groups had higher comorbidity rates than privately insured patients (37.3%, p < 0.0001). Only 67.7% of Medicaid patients had primary care providers (PCPs) versus 91.5% of Medicare and 86.3% of privately insured patients (p = 0.009) at the time of presentation. Tumor diameter at diagnosis was largest for Medicaid (4.7 cm) versus Medicare (4.1 cm) and privately insured patients (4.2 cm, p = 0.03). Preoperative (70 vs 90, p = 0.02) and postoperative (80 vs 90, p = 0.03) Karnofsky Performance Scale (KPS) scores were lowest for Medicaid versus non-Medicaid patients, while in subgroup analysis, postoperative KPS score was lowest for Medicaid patients (80, vs 90 for Medicare and 90 for private insurance; p = 0.03). Medicaid patients had significantly shorter median overall survival (10.7 months vs 12.8 months for Medicare and 15.8 months for private insurance; p = 0.02). Quality-adjusted life year (QALY) scores were 0.66 and 1.05 for Medicaid and non-Medicaid patients, respectively (p = 0.036). The incremental cost per QALY was $29,963 lower for the non-Medicaid cohort.

CONCLUSIONS

Patients with GBMs and Medicaid have higher surgical costs, longer lengths of stay, poorer survival, and lower QALY scores. This study indicates that these patients lack PCPs, have more comorbidities, and present later in the disease course with larger tumors; these factors may drive the poorer postoperative function and greater consumption of hospital resources that were identified. Given limited resources and rising healthcare costs, factors such as access to PCPs, equitable adjuvant therapy, and early screening/diagnosis of disease need to be improved in order to improve prognosis and reduce hospital costs for patients with GBM.

Potential differences between monolingual and bilingual patients in approach and outcome after awake brain surgery

INTRODUCTION

20.8% of the United States population and 67% of the European population speak two or more languages. Intraoperative different languages, mapping, and localization are crucial. This investigation aims to address three questions between BL and ML patients: (1) Are there differences in complications (i.e. seizures) and DECS techniques during intra-operative brain mapping? (2) Is EOR different? and (3) Are there differences in the recovery pattern post-surgery?

METHODS

Data from 56 patients that underwent left-sided awake craniotomy for tumors infiltrating possible dominant hemisphere language areas from September 2016 to June 2019 were identified and analyzed in this study; 14 BL and 42 ML control patients. Patient demographics, education level, and the age of language acquisition were documented and evaluated. fMRI was performed on all participants.

RESULTS

0 (0%) BL and 3 (7%) ML experienced intraoperative seizures (P = 0.73). BL patients received a higher direct DECS current in comparison to the ML patients (average = 4.7, 3.8, respectively, P = 0.03). The extent of resection was higher in ML patients in comparison to the BL patients (80.9 vs. 64.8, respectively, P = 0.04). The post-operative KPS scores were higher in BL patients in comparison to ML patients (84.3, 77.4, respectively, P = 0.03). BL showed lower drop in post-operative KPS in comparison to ML patients (- 4.3, - 8.7, respectively, P = 0.03).

CONCLUSION

We show that BL patients have a lower incidence of intra-operative seizures, lower EOR, higher post-operative KPS and tolerate higher DECS current, in comparison to ML patients.

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.

Evaluation of cost and survival in intracranial gliomas using the Value Driven Outcomes database: a retrospective cohort analysis

OBJECTIVE

Gliomas occur in 3-4 individuals per 100,000 individuals and are one of the most common primary brain tumors. Treatment options are limited for gliomas despite the progressive nature of the disease. The authors used the Value Driven Outcomes (VDO) database to identify cost drivers and subgroups that are involved in the surgical treatment of gliomas.

METHODS

A retrospective cohort of patients with gliomas treated at the authors' institution from August 2011 to February 2018 was evaluated using medical records and the VDO database.

RESULTS

A total of 263 patients with intracranial gliomas met the authors' inclusion criteria and were included in the analysis (WHO grade I: 2.0%; grade II: 18.5%; grade III: 18.1%; and grade IV: 61.4%). Facility costs were the major (64.4%) cost driver followed by supplies (16.2%), pharmacy (10.1%), imaging (4.5%), and laboratory (4.7%). Univariate analysis of cost contributors demonstrated that American Society of Anesthesiologists physical status (p = 0.002), tumor recurrence (p = 0.06), Karnofsky Performance Scale score (p = 0.002), length of stay (LOS) (p = 0.0001), and maximal tumor size (p = 0.03) contributed significantly to the total costs. However, on multivariate analysis, only LOS (p = 0.0001) contributed significantly to total costs. More extensive tumor resection in WHO grade III and IV tumors was associated with significant improvement in survival (p = 0.004 and p = 0.02, respectively).

CONCLUSIONS

Understanding care costs is challenging because of the highly complex, fragmented, and variable nature of healthcare delivery. Adopting effective strategies that would reduce facility costs and limit LOS is likely the most important aspect in reducing intracranial glioma treatment costs.

Functional Mapping for Glioma Surgery: A Propensity-Matched Analysis of Outcomes and Cost

OBJECTIVE

To compare clinical outcomes and payments between glioma resections with and without functional mapping.

METHODS

The Thomas Reuters MarketScan national longitudinal database was used to identify patients undergoing resection of supratentorial primary malignant glioma with or without functional mapping between 2007 and 2016. Patients were stratified into mapped and unmapped (conventional) groups and subsequently propensity-matched based on demographics, clinical comorbidities, and surgical characteristics (i.e., use of stereotactic navigation, microscope, and intratumoral chemotherapy). Outcomes and charges were compared between matched groups using bivariate analyses.

RESULTS

A total of 14,037 patients were identified, of whom 796 (6.0%) received functional mapping. Propensity matching (1:1) resulted in 796 mapped patients and 796 propensity-matched controls. Thirty-day postoperative rates of new-onset seizures, cerebral edema, hemorrhage, and neurologic deficits were significantly lower for the functional mapping group (all P < 0.05). Functional mapping was also associated with shorter hospital length of stay (P = 0.0144), lower 30-day rates of emergency department visits (P = 0.0001), and fewer reoperations (P = 0.0068). Total costs of initial admission were not significantly different between groups.

CONCLUSIONS

Intraoperative functional mapping during glioma resection was associated with decreased complications, reoperations, emergency department visits, and shorter lengths of stay. Furthermore, total charges of mapped resections were not significantly different from those of conventional resections. These findings support the usefulness of functional mapping for resection of supratentorial primary malignant gliomas.

Management of Glioblastoma, Present and Future

Glioblastomas are the most common malignant brain tumor and despite extensive research have a dismal prognosis. This review focuses on the current treatment paradigms of glioblastoma and highlights current advances in surgical approaches, imaging techniques, molecular diagnostics, and translational efforts. Several promising clinical trials in immunotherapy and personalized medicine are discussed and the importance of quality of life in the patients and their caregivers both during active treatment and survivorship is also commented on.

Following the light in glioma surgery: a comparison of sodium fluorescein and 5-aminolevulinic acid as surgical adjuncts in glioma resection

Gliomas are molecularly complex neoplasms and require a multidisciplinary approach to treatment. Maximal safe resection is often the initial goal of treatment and extent of resection (EOR) is an important prognostic factor correlating with both progression-free-survival (PFS) and overall survival (OS). Postoperative patient outcome is also a critical and independent prognosticator and high EOR must not be achieved at the expense of good functional outcome. Several intraoperative adjuvant techniques have been developed to help the surgeon push the boundaries of EOR while maintaining safety. Fluorescence-guided surgery for brain tumors is a contemporary adjuvant technique that allows for intraoperative delineation of diseased and normal brain thus improving maximal safe resection. The most extensively used fluorophores are 5-aminolevulinic acid (5-ALA) and sodium fluorescein (SFL). These fluorophores have different spectrophotometric properties, mechanisms of action and considerations for use. Both have demonstrated utility in neurosurgical oncology. They are safe and both are FDA approved for use as surgical adjuncts during resection of primary CNS neoplasms although they have been used with varying success for other tumor types. When combined with other surgical adjuvant strategies such as neuronavigation, intraoperative ultrasound, intraoperative MRI, awake resection and/or electrophysiological mapping/monitoring, fluorescence-guided resection appears to further improve resection quality in regard to EOR and safety. In this article, we review the current knowledge related to both fluorophores for brain tumor resection, their benefits, and pitfalls, as well as the major advantages associated with their use. We also briefly review additional fluorophores in early clinical development. Fluorescence-guided surgery is a novel surgical adjuvant which allows for real-time delineation of neoplastic tissues. The most widely used fluorophores are 5-ALA and SFL. They are safe compounds and there is a large body of evidence suggesting improvement in EOR when these are employed. There are nuances to the use of each; the fluorescence intensity is dose-dependent in either case and the sensitivity and specificity for various tumors vary widely. Additional prospective studies will be necessary to parse the impact of this technique and these fluorophores on survival metrics.

Novel Wavelength-Specific Blue Light-Emitting Headlamp for 5-Aminolevulinic Acid Fluorescence-Guided Resection of Glioblastoma

OBJECTIVE

Extent of resection of glioblastoma is an important predictor for overall survival, and 5-aminolevulinic acid fluorescence-guided surgery can improve outcomes. However, the technique requires the installation of a blue light module on operative microscopes and may be cost prohibitive. A novel and economical blue light-emitting headlamp was designed, and its clinical utility was explored.

METHODS

A remote-controlled dual light emitting diode headlamp system was constructed with 1 diode emitting white light and the other blue. Spectrographic analysis of the blue light emitted from a commercial operative microscope and the headlamp was performed. A comparative evaluation of the 2 illumination systems was conducted for 3 patients who underwent craniotomy for glioblastoma resection. Histologic examination of the fluorescing tissue detected by the headlamp was performed, and the extent of resection was assessed by postoperative day 1 magnetic resonance imaging.

RESULTS

Spectrography of blue light emitted from the headlamp system was wavelength specific with a single emission peak at 416 nm and a linewidth of 35 nm. In contrast, blue light from the microscope (peak: 426 nm) had a wider linewidth of 54 nm and was not wavelength specific with additional infrared radiation detected. Gross or near-total resection of contrast-enhancing glioblastoma was performed for all 3 patients. Intraoperatively, comparable tumor fluorescence was observed under microscope and headlamp blue light illumination. Histologic examination of tissue fluorescing under headlamp blue light confirmed the presence of glioblastoma.

CONCLUSIONS

This novel proof-of-concept blue light-emitting headlamp device may offer an opportunity for institutions with limited resources to implement 5-aminolevulinic acid fluorescence-guided glioblastoma resections.

Cost-effectiveness of Intraoperative MRI for Treatment of High-Grade Gliomas

Background Intraoperative MRI has been shown to improve gross-total resection of high-grade glioma. However, to the knowledge of the authors, the cost-effectiveness of intraoperative MRI has not been established. Purpose To construct a clinical decision analysis model for assessing intraoperative MRI in the treatment of high-grade glioma. Materials and Methods An integrated five-state microsimulation model was constructed to follow patients with high-grade glioma. One-hundred-thousand patients treated with intraoperative MRI were compared with 100 000 patients who were treated without intraoperative MRI from initial resection and debulking until death (median age at initial resection, 55 years). After the operation and treatment of complications, patients existed in one of three health states: progression-free survival (PFS), progressive disease, or dead. Patients with recurrence were offered up to two repeated resections. PFS, valuation of health states (utility values), probabilities, and costs were obtained from randomized controlled trials whenever possible. Otherwise, national databases, registries, and nonrandomized trials were used. Uncertainty in model inputs was assessed by using deterministic and probabilistic sensitivity analyses. A health care perspective was used for this analysis. A willingness-to-pay threshold of $100 000 per quality-adjusted life year (QALY) gained was used to determine cost efficacy. Results Intraoperative MRI yielded an incremental benefit of 0.18 QALYs (1.34 QALYs with intraoperative MRI vs 1.16 QALYs without) at an incremental cost of $13 447 ($176 460 with intraoperative MRI vs $163 013 without) in microsimulation modeling, resulting in an incremental cost-effectiveness ratio of $76 442 per QALY. Because of parameter distributions, probabilistic sensitivity analysis demonstrated that intraoperative MRI had a 99.5% chance of cost-effectiveness at a willingness-to-pay threshold of $100 000 per QALY. Conclusion Intraoperative MRI is likely to be a cost-effective modality in the treatment of high-grade glioma. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Bettmann in this issue.

What is the advance of extent of resection in glioblastoma surgical treatment-a systematic review

Glioblastoma multiform (GBM) is the most common malignant brain tumor characterized by poor prognosis, increased invasiveness, and high relapse rates. The relative survival estimates are quite low in spite of the standard treatment for GBM in recent years. Now, it has been gradually accepted that the amount of tumor mass removed correlates with longer survival rates. Although new technique advances allowing intraoperative analysis of tumor and normal brain tissue and functional paradigms based on stimulation techniques to map eloquent areas have been used for GBM resection, visual identification of tumor margins still remains a challenge for neurosurgeons. This article attempts to review and summarize the evolution of surgical resection for glioblastomas.

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.

Who Needs Sleep? An Analysis of Patient Tolerance in Awake Craniotomy

BACKGROUND

Awake craniotomy (AC) is generally a safe and effective procedure; however, a small but not insignificant portion of cases are aborted due to patient intolerance of the awake portion of surgery. There is not yet a firm understanding of what characteristics indicate patient tolerance or failure of AC.

METHODS

We retrospectively reviewed a single-surgeon database of patients treated by AC over a 5-year period. Charts were reviewed for demographic, clinical, and operative characteristics, including anesthetic administration during the awake portion of surgery. Statistical analysis was performed to determine which factors predicted patient tolerance or failure.

RESULTS

Our study cohort comprised 120 patients with an average age of 56.0 ± 15.2 years. A majority of patients were male (55.8%). The most common surgical indication was tumor (95.8%), with gliobastoma as the most common diagnosis (43.3%). Male sex predicted surgical tolerance on univariate analysis (P = 0.015). Remifentanil administration was associated with surgical failure on univariate analysis (P = 0.068), and also predicted failure on multivariate analysis (P = 0.030). Preoperative seizure, ketamine administration, and right-sided surgery each predicted patient tolerance, but did not achieve statistical significance. Similarly, respiratory comorbidity was associated with surgical failure, but did not achieve significance.

CONCLUSIONS

AC remains an effective treatment option; the majority of patients tolerate the procedure without issue. Male patients have lower rates of surgical failure, whereas remifentanil administration may increase failure rate.

Advances in Brain Tumor Surgery for Glioblastoma in Adults

Glioblastoma (GBM) is the most common primary intracranial neoplasia, and is characterized by its extremely poor prognosis. Despite maximum surgery, chemotherapy, and radiation, the histological heterogeneity of GBM makes total eradication impossible, due to residual cancer cells invading the parenchyma, which is not otherwise seen in radiographic images. Even with gross total resection, the heterogeneity and the dormant nature of brain tumor initiating cells allow for therapeutic evasion, contributing to its recurrence and malignant progression, and severely impacting survival. Visual delimitation of the tumor’s margins with common surgical techniques is a challenge faced by many surgeons. In an attempt to achieve optimal safe resection, advances in approaches allowing intraoperative analysis of cancer and non-cancer tissue have been developed and applied in humans resulting in improved outcomes. In addition, functional paradigms based on stimulation techniques to map the brain’s electrical activity have optimized glioma resection in eloquent areas such as the Broca’s, Wernike’s and perirolandic areas. In this review, we will elaborate on the current standard therapy for newly diagnosed and recurrent glioblastoma with a focus on surgical approaches. We will describe current technologies used for glioma resection, such as awake craniotomy, fluorescence guided surgery, laser interstitial thermal therapy and intraoperative mass spectrometry. Additionally, we will describe a newly developed tool that has shown promising results in preclinical experiments for brain cancer: optical coherence tomography.

Comparative Cost Analysis of Endoscopic versus Microscopic Endonasal Transsphenoidal Surgery for Pituitary Adenomas

Objective  This study presents a comparative analysis of cost efficacy between the microscopic and endoscopic transsphenoidal approaches, evaluating neurological outcome, extent of resection (EOR), and inpatient hospital costs. Design  This study was a retrospective chart review. Setting  This study was conducted at a tertiary care center. Participants  The study group consisted of 68 patients with transsphenoidal surgeries between January 2007 and January 2014. Main Outcome Measures  Two-sample t -tests and Pearson's chi-square test evaluated inpatient costs, quality-adjusted life years (QALYs), volumetric EOR, and neurological outcomes. Results  Total inpatient costs per patient was $22,853 in the microscopic group and less ($19,736) in the endoscopic group ( p  = 0.049). Operating room costs were $5,974 in the microscopic group and lower in the endoscopic group ($5,045; p  = 0.038). Operative time was 203.6 minutes in the microscopic group and 166.3 minutes in the endoscopic group ( p  = 0.032). The QALY score, length of hospital stay, and postoperative outcomes were found to be similar between the two cohorts. Multivariate linear regression modeling suggested that length of stay ( p  < 0.001) and operative time ( p  = 0.008) were important factors that influenced total inpatient costs following transsphenoidal surgery. Conclusion  This study shows that transsphenoidal surgery is more cost effective with the endoscopic approach than with the microscopic approach and depends on efficiency in the operating room as well as reduction in the length of hospitalization.

Comparative analysis of monotherapy versus duotherapy antiseizure drug management for postoperative seizure control in patients undergoing an awake craniotomy

OBJECTIVE Postoperative seizures are a common complication in patients undergoing an awake craniotomy, given the cortical manipulation during tumor resection and the electrical cortical stimulation for brain mapping. However, little evidence exists about the efficacy of postoperative seizure prophylaxis. This study aims to determine the most appropriate antiseizure drug (ASD) management regimen following an awake craniotomy. METHODS The authors performed a retrospective analysis of data pertaining to patients who underwent an awake craniotomy for brain tumor from 2007 to 2015 performed by a single surgeon. Patients were divided into 2 groups, those who received a single ASD (the monotherapy group) and those who received 2 types of ASDs (the duotherapy group). Patient demographics, symptoms, tumor characteristics, hospitalization details, and seizure outcome were evaluated. Multivariable logistic regression was used to evaluate numerous clinical variables associated with postoperative seizures. RESULTS A total of 81 patients underwent an awake craniotomy for tumor resection of an eloquent brain lesion. Preoperative baseline characteristics were comparable between the 2 groups. The postoperative seizure rate was 21.7% in the monotherapy group and 5.7% in the duotherapy group (p = 0.044). Seizure outcome at 6 months' follow-up was assessed with the Engel classification scale. The duotherapy group had a significantly higher proportion of seizure-free (Engel Class I) patients than the monotherapy group (90% vs 60%, p = 0.027). The length of stay was similar, 4.02 days in the monotherapy group and 4.51 days in the duotherapy group (p = 0.193). The 90-day readmission rate was higher for the monotherapy group (26.1% vs 8.5% in the duotherapy group, p = 0.044). Multivariate logistic regression showed that preoperative seizure history was a significant predictor for postoperative seizures following an awake craniotomy (OR 2.08, 95% CI 0.56-0.90, p < 0.001). CONCLUSIONS Patients with a preoperative seizure history may be at a higher risk for postoperative seizures following an awake craniotomy and may benefit from better postoperative seizure control with postoperative ASD duotherapy.

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.

Comparative volumetric analysis of the extent of resection of molecularly and histologically distinct low grade gliomas and its role on survival

The authors investigate the role of extent of resection (EOR) and genetic markers on patient outcome and survival for LGGs. We conducted a retrospective cohort between 2005 and 2015, of 109 adult patients who underwent surgery for a LGG by a single surgeon. Volumetric computations of MRI studies were conducted to evaluate the EOR, and genetic markers (IDH1, 1p/19q co-deletion, and p53) were assessed and their effects on survival and neurological outcome were evaluated. The median EOR was 88.1%. Permanent postoperative neurological deficits were seen in 4.6% of patients. EOR was a significant predictor for both overall survival (OS) (hazard ratio [HR] = 0.979, 95% CI 0.961-0.980, p = 0.029) and progression free survival (PFS) (HR = 0.982, 95% CI 0.968-0.997, p = 0.018). Malignant progression free survival (MPFS) was predicted by the 1p/19q co-deletion (HR = 0.148, 95% CI 0.019-1.148, p = 0.048). Patients with EOR of 100% had a significantly better OS than EOR less than 90% (p = 0.038). Patients with an EOR of at least 76% had a better OS than EOR less than 76% (p = 0.025). Patients with an EOR of at least 71% had a better PFS than EOR less than 71% (p = 0.030). Preoperative tumor volume was found to have significant association with EOR (R² = 0.049, p = 0.031). Increased EOR is associated with improved OS and PFS survival outcomes, while 1p/19q co-deletion provides improved MPFS. Understanding both surgical resections and molecular markers of the tumor are important for effective management of LGG patients.