Volume-outcome relationships in neurosurgery

Defining benchmark outcomes for mesial temporal lobe epilepsy surgery: A global multicenter analysis of 1119 cases

OBJECTIVE

Benchmarking has been proposed to reflect surgical quality and represents the highest standard reference values for desirable results. We sought to determine benchmark outcomes in patients after surgery for drug-resistant mesial temporal lobe epilepsy (MTLE).

METHODS

This retrospective multicenter study included patients who underwent MTLE surgery at 19 expert centers on five continents. Benchmarks were defined for 15 endpoints covering surgery and epilepsy outcome at discharge, 1 year after surgery, and the last available follow-up. Patients were risk-stratified by applying outcome-relevant comorbidities, and benchmarks were calculated for low-risk ("benchmark") cases. Respective measures were derived from the median value at each center, and the 75th percentile was considered the benchmark cutoff.

RESULTS

A total of 1119 patients with a mean age (range) of 36.7 (1-74) years and a male-to-female ratio of 1:1.1 were included. Most patients (59.2%) underwent anterior temporal lobe resection with amygdalohippocampectomy. The overall rate of complications or neurological deficits was 14.4%, with no in-hospital death. After risk stratification, 377 (33.7%) benchmark cases of 1119 patients were identified, representing 13.6%-72.9% of cases per center and leaving 742 patients in the high-risk cohort. Benchmark cutoffs for any complication, clinically apparent stroke, and reoperation rate at discharge were ≤24.6%, ≤.5%, and ≤3.9%, respectively. A favorable seizure outcome (defined as International League Against Epilepsy class I and II) was reached in 83.6% at 1 year and 79.0% at the last follow-up in benchmark cases, leading to benchmark cutoffs of ≥75.2% (1-year follow-up) and ≥69.5% (mean follow-up of 39.0 months).

SIGNIFICANCE

This study presents internationally applicable benchmark outcomes for the efficacy and safety of MTLE surgery. It may allow for comparison between centers, patient registries, and novel surgical and interventional techniques.

Choreographed expansion of services results in decreased patient burden without compromise of outcomes: An assessment of the Ontario experience

Background

Neuro-oncology care in Ontario, Canada has been historically centralized, at times requiring significant travel on the part of patients. Toward observing the goal of patient-centered care and reducing patient burden, 2 additional regional cancer centres (RCC) capable of neuro-oncology care delivery were introduced in 2016. This study evaluates the impact of increased regionalization of neuro-oncology services, from 11 to 13 oncology centers, on healthcare utilization and travel burden for glioblastoma (GBM) patients in Ontario.

Methods

We present a cohort of GBM patients diagnosed between 2010 and 2019. Incidence of GBM and treatment modalities were identified using provincial health administrative databases. A geographic information system and spatial analysis were used to estimate travel time from patient residences to neuro-oncology RCCs.

Results

Among the 5242 GBM patients, 79% received radiation as part of treatment. Median travel time to the closest RCC was higher for patients who did not receive radiation as part of treatment than for patients who did (P = .03). After 2016, the volume of patients receiving radiation at their local RCC increased from 62% to 69% and the median travel time to treatment RCCs decreased (P = .0072). The 2 new RCCs treated 35% and 41% of patients within their respective catchment areas. Receipt of standard of care, surgery, and chemoradiation (CRT), increased by 11%.

Conclusions

Regionalization resulted in changes in the healthcare utilization patterns in Ontario consistent with decreased patient travel burden for patients with GBM. Focused regionalization did not come at the cost of decreased quality of care, as determined by the delivery of a standard of care.

The Relationship Between Procedural Volume, Hospital Quality, and Postoperative Mortality in Pediatric Neurosurgery: Review of the Literature

BACKGROUND

Studies of neurosurgical pediatric patients associate treatment at low-volume hospitals and by low-volume surgeons with increased odds of adverse outcomes. Although these associations suggest that increased centralization of care could be considered, we evaluate whether confounding endogenous factors mitigate against the proposed outcome benefits.

METHODS

Literature review of English language articles from 1999 to 2021. We included articles that assessed volume-outcome effects in pediatric neurosurgical patients.

RESULTS

Twelve papers were included from 1999 to 2021. Primary outcomes included mortality (9), length of stay (LOS) (6), complications (4), and shunt revision/failure rates (3). Volume was measured at the hospital level (8) and at the surgeon level (6). Four papers found that higher volume hospitals had lower odds of mortality. Two papers found that hospitals with higher volume had fewer complications. Two papers found that higher volume surgeons had decreased mortality (odds ratio [OR] 0.09-0.3). One paper found that high-volume surgeons had fewer complications (-2.4%; P = 0.006). After controlling for hospital factors (HF), two out of 7 analyses remained significant. Five analyses did not control for HF.

CONCLUSIONS

The literature consistently demonstrates a relationship between higher hospital and surgeon volume and better outcomes for pediatric neurosurgical patients. Of the 7 articles that assessed HF, only 2 analyses found that surgical volume remained associated with better outcomes. No reports assessed the degree of centralization already present. The call for centralization of pediatric care should be tempered until variables such as hospital factors, distribution of cases, and clinical thresholds can be defined and studied.

Assessing the volume-outcome relationship of carotid artery stenting in nationwide administrative data: a challenge of patient population bias

BACKGROUND

Studies have shown an association between surgical treatment volume and improved quality metrics. This study evaluated nationwide results in carotid artery stenting (CAS) procedural readmission rates, costs, and length of stay based on hospital treatment volume.

METHODS

We used the Nationwide Readmissions Database for carotid stenosis from 2010 to 2015. Patients receiving CAS were matched based on demographics, illness severity, and relevant comorbidities. Patients were matched 1:1 between low- and high-volume centers using a non-parametric preprocessing matching program to adjust for parametric causal inferences. Nearest-neighbor propensity score matching was performed using logit distance.

RESULTS

Low- and high-volume centers admitted a mean (SD) of 4.68 (3.79) and 25.10 (16.86) patients undergoing CAS per hospital, respectively. Comorbidities were significantly different and initially could not be adequately matched. Because of significant differences in baseline patient population characteristics after attempted matching between low- and high-volume centers, we used propensity adjustment with multivariate analysis. Using this alternative approach, no significant differences were observed between low- and high-volume centers for the presence of any complication, postoperative stroke, postoperative myocardial infarction, and readmission at 30 days.

CONCLUSION

In 1:1 nearest-neighbor matching with a high number of patients, our analysis did not result in well-matched cohorts for the effect of case volume on outcomes. Comparing analytical techniques for various outcomes highlights that outcome disparities may not be related to quality differences based on hospital size, but rather variability in patient populations between low- and high-volume institutions.

Single-surgeon approach in microvascular decompression for trigeminal neuralgia: Lessons from an Indonesian Tertiary-Level Neurological Center

BACKGROUND

Microvascular decompression (MVD) is effective for refractory trigeminal neuralgia (TN), but its accessibility is often limited in lower-to-middle-income countries (LMICs). This study aims to assess the impact of implementing a single-surgeon policy on MVD for TN in LMICs.

METHODS

A prospective cohort study was conducted from 2014 to 2020, comparing outcomes between multi-surgeon and single-surgeon policies. Residents were included in MVD procedures starting in 2019. The Barrow Neurological Institute (BNI) pain scale (P), numbness scale (N), and result conclusion scale (P + N) were used to evaluate outcomes (1 week, 1 month, 1 year, and yearly thereafter). Propensity score matching was performed before comparing the groups. Pain-free survival was assessed using Kaplan-Meier and Cox-regression analysis.

RESULTS

We comprehensively analyzed data from 72 patients with a minimum one-year follow-up. The implementation of the single-surgeon policy had several notable impacts. Firstly, it led to an increased referral rate (p < 0.05) and a reduced duration to surgery (p < 0.05). During MVD, there was a significant increase in the identification of complex compression (p < 0.05) and a reduced frequency of internal neurolysis (p < 0.05). After surgery, the single-surgeon group exhibited a superior pain-control profile (RR 1.9, p < 0.001; ARR 26-36%), higher pain-free survival rate (p < 0.001), lower likelihood of pain recurrence (HR 0.2, p < 0.0001), and fewer additional surgical interventions compared to the multi-surgeon group. Moreover, the involvement of residents did not significantly impact surgical outcomes.

CONCLUSIONS

Implementing a single-surgeon policy for MVD in LMICs has the potential to improve surgical outcomes, provide social benefits, and offer educational opportunities.

Effect of institution volume on mortality and outcomes in osteoporotic hip fracture care

Hospitals that treat more patients with osteoporotic hip fractures do not generally have better care outcomes than those that treat fewer hip fracture patients. Institutions that do look after more such patients tend, however, to more consistently perform relevant health assessments.

INTRODUCTION

An inveterate link has been found between institution case volume and a wide range of clinical outcomes; for a host of medical and surgical conditions. Hip fracture patients, notwithstanding the significance of this injury, have largely been overlooked with regard to this important evaluation.

METHODS

We used the UK National Hip Fracture database to determine the effect of institution hip fracture case volume on hip fracture healthcare outcomes in 2019. Using logistic regression for each healthcare outcome, we compared the best performing 50 units with the poorest performing 50 institutions to determine if the unit volume was associated with performance in each particular outcome.

RESULTS

There were 175 institutions with included 67,673 patients involved. The number of hip fractures between units ranged from 86 to 952. Larger units tendered to perform health assessments more consistently and mobilise patients more expeditiously post-operatively. However, patients treated at large institutions did not have any shorter lengths of stay. With regard to most other outcomes there was no association between the unit number of cases and performance; notably mortality, compliance with best practice tariff, time to surgery, the proportion of eligible patients undergoing total hip arthroplasty, length of stay delirium risk and pressure sore risk.

CONCLUSIONS

There is no relationship between unit volume and the majority of health care outcomes. It would seem that larger institutions tend to perform better at parameters that are dependent upon personnel numbers. However, where the outcome is contingent, even partially, on physical infrastructure capacity, there was no difference between larger and smaller units.

Radiocephalic Arteriovenous Fistula Patency and Use

We sought to confirm and extend the understanding of clinical outcomes following creation of a common distal autogenous access, the radiocephalic arteriovenous fistula (RCAVF).

Mini-abstract: In this post hoc analysis of randomized clinical trial data including 914 adults with chronic kidney disease, the most robust predictors of radiocephalic arteriovenous fistula patency were larger cephalic vein diameter and access creation prior to a chronic hemodialysis requirement. Successful use occurred at increased rates in men, patients with larger diameter cephalic veins, smaller diameter arteries (albeit ≥2 mm), and when accesses were created using regional anesthesia and at higher volume centers.

Hospital Case-Volume and Patient Outcomes Following Pediatric Brain Tumor Surgery in the Pediatric Health Information System

BACKGROUND

Markers of quality of care in various surgical specialties have been shown to correlate with hospital volumes. This study investigates the effect of hospital volume and patient-related factors on the outcomes of children undergoing brain tumor resection.

METHODS

We examined the data within the Pediatric Health Information System (PHIS) for children aged zero to 17 years undergoing brain tumor resection between 2016 and 2020. Length of hospital stay (LOS), costs, and reoperation rates were analyzed for associations with hospital case-volume, patient factors, and other hospital-related factors.

RESULTS

A total of 2568 patients were included in this PHIS analysis. After adjusting for covariates, care provided by high-case-volume hospitals led to shorter LOS (P = 0.01). The effect of hospital case-volume on median cost was present on univariate analysis (US $63,845 at low-volume hospital versus US $54,909 at high-volume hospital, P = 0.002); this finding was attenuated by LOS. A trend was observed between reoperation rates and hospital case-volume, with lowest quartile volume hospitals having higher odds of reoperation than hospitals with volumes in the highest quartile (P = 0.06). Racial and ethnic minorities, medical comorbidities, and other sociodemographic factors were associated with poorer outcomes following surgery.

CONCLUSIONS

Centering care around high-case-volume hospitals can potentially lead to shorter hospital stays and decreased costs for children with brain tumors. This PHIS article highlights the association of the studied outcomes with certain sociodemographic factors and illustrates that inequalities in pediatric health care still exist. Further efforts are required to understand and eliminate these potentially harmful differences.

The National Inpatient Sample: A Primer for Neurosurgical Big Data Research and Systematic Review

OBJECTIVE

The National Inpatient Sample - the largest all-payer inpatient database in the United States - is an important instrument for big data analysis of neurosurgical inquiries. However, earlier research has determined that many NIS studies are limited by common methodological pitfalls. In this study, we provide the first primer of NIS methodological procedures in the setting of neurosurgical research and review all published neurosurgical studies utilizing the NIS.

METHODS

We designed a protocol for neurosurgical big data research using the NIS, based on the authors' subject matter expertise, NIS documentation, and input and verification from the Healthcare Cost and Utilization Project. We subsequently used a comprehensive search strategy to identify all neurosurgical studies utilizing the NIS in the PubMed and MEDLINE, Embase, and Web of Science databases from inception to August 2021. Studies underwent qualitative categorization (years of the NIS studied, neurosurgical subspecialty, age group, and thematic focus of study objective) and analysis of longitudinal trends.

RESULTS

We identified a canonical, four-step protocol for NIS analysis: study population selection, defining additional clinical variables, identification and coding of outcomes, and statistical analysis. Methodological nuances discussed include identifying neurosurgery-specific admissions, addressing missing data, calculating additional severity and hospital-specific metrics, coding perioperative complications, and applying survey weights to make nationwide estimates. Inherent database limitations and common pitfalls of NIS studies discussed include lack of disease process-specific variables and data following the index admission, inability to calculate certain hospital-specific variables after 2011, performing state-level analyses, conflating hospitalization charges and costs, and not following proper statistical methodology for performing survey-weighted regression. In a systematic review, we identified 647 neurosurgical studies utilizing the NIS. While almost 60% of studies were published after 2015, <10% of studies analyzed NIS data after 2015. The average sample size of studies was 507,352 patients (standard deviation=2,739,900). Most studies analyzed cranial procedures (58.1%) and adults (68.1%). The most prevalent topic areas analyzed were surgical outcome trends (35.7%) and health policy and economics (17.8%), while patient disparities (9.4%) and surgeon or hospital volume (6.6%) were the least studied.

CONCLUSIONS

We present a standardized methodology to analyze the NIS, systematically review the state of the NIS neurosurgical literature, suggest potential future directions for neurosurgical big data inquiries, and outline recommendations to improve the design of future neurosurgical data instruments.

International Consensus Statement on the diagnosis, multidisciplinary management and lifelong care of individuals with achondroplasia

Achondroplasia, the most common skeletal dysplasia, is characterized by a variety of medical, functional and psychosocial challenges across the lifespan. The condition is caused by a common, recurring, gain-of-function mutation in FGFR3, the gene that encodes fibroblast growth factor receptor 3. This mutation leads to impaired endochondral ossification of the human skeleton. The clinical and radiographic hallmarks of achondroplasia make accurate diagnosis possible in most patients. However, marked variability exists in the clinical care pathways and protocols practised by clinicians who manage children and adults with this condition. A group of 55 international experts from 16 countries and 5 continents have developed consensus statements and recommendations that aim to capture the key challenges and optimal management of achondroplasia across each major life stage and sub-specialty area, using a modified Delphi process. The primary purpose of this first International Consensus Statement is to facilitate the improvement and standardization of care for children and adults with achondroplasia worldwide in order to optimize their clinical outcomes and quality of life.

Ethical considerations in the surgical and neuromodulatory treatment of epilepsy

Surgical resection and neuromodulation are well-established treatments for those with medically refractory epilepsy. These treatments entail important ethical considerations beyond those which extend to the treatment of epilepsy generally. In this paper, the authors explore these unique considerations through a framework that relates foundational principles of bioethics to features of resective epilepsy surgery and neuromodulation. The authors conducted a literature review to identify ethical considerations for a variety of epilepsy surgery procedures and to examine how foundational principles in bioethics may inform treatment decisions. Healthcare providers should be cognizant of how an increased prevalence of somatic and psychiatric comorbidities, the dynamic nature of symptom burden over time, the individual and systemic barriers to treatment, and variable sociocultural contexts constitute important ethical considerations regarding the use of surgery or neuromodulation for the treatment of epilepsy. Moreover, careful attention should be paid to how resective epilepsy surgery and neuromodulation relate to notions of patient autonomy, safety and privacy, and the shared responsibility for device management and maintenance. A three-tiered approach-(1) gathering information and assessing the risks and benefits of different treatment options, (2) clear communication with patient or proxy with awareness of patient values and barriers to treatment, and (3) long-term decision maintenance through continued identification of gaps in understanding and provision of information-allows for optimal treatment of the individual person with epilepsy while minimizing disparities in epilepsy care.

What is the current clinical practice in pituitary adenoma surgery in Europe? European Pituitary Adenoma Surgery Survey (EU-PASS) results-technical part

Pituitary adenoma surgery has evolved rapidly in recent decades, changing clinical practice markedly and raising new challenges. There is no current consensus or guidelines for perioperative care that includes possible complication management. This study aims to determine current practice across European neurosurgical centres. We created a list of eligible departments performing pituitary adenoma surgery based on cooperation with EANS, national neurosurgical societies, and personal communication with local neurosurgeons. We contacted the chairpersons from each department and asked them (or another responsible neurosurgeon) to fill out the survey. The survey consisted of 58 questions. For further analysis, departments were divided into subgroups: "academic"/ "non-academic centre", "high-volume"/"low-volume", "mainly endoscopic"/ "mainly microscopic"/ "mixed practise", and by geographical regions. Data from 254 departments from 34 countries were obtained. The average time to complete the survey was 18 min. Notably, the endoscopic approach is the predominant surgical approach in Europe, used in 56.8% of the centres. In routine cases without intraoperative cerebrospinal fluid leak, high-volume centres are less pedantic with sellar closure when compared with low-volume centres (p < 0.001). On the other hand, when a postoperative cerebrospinal fluid leak occurs, high-volume centres are more active and indicate early reoperation (p = 0.013). Less than 15% of the participating centres perform early postoperative MRI scans. Marked variation was noted among different groups of respondents and some contentious issues are discussed. Such information can encourage useful debate about the reasons for the variations seen and perhaps help develop standardised protocols to improve patient outcomes. A future research focus is to compare European results with other regions.

Intermediate-grade brain arteriovenous malformations and the boundary of operability using the supplemented Spetzler-Martin grading system

OBJECTIVE

Supplemented Spetzler-Martin grading (Supp-SM), which is the combination of Spetzler-Martin and Lawton-Young grades, was validated as being more accurate than stand-alone Spetzler-Martin grading, but an operability cutoff was not established. In this study, the authors surgically treated intermediate-grade AVMs to provide prognostic factors for neurological outcomes and to define AVMs at the boundary of operability.

METHODS

Surgically treated Supp-SM intermediate-grade (5, 6, and 7) AVMs were analyzed from 2011 to 2018 at two medical centers. Worsened neurological outcomes were defined as increased modified Rankin Scale (mRS) scores on postoperative examinations. A second analysis of 2000-2011 data for Supp-SM grade 6 and 7 AVMs was performed to determine the subtypes with improved or unchanged outcomes. Patients were separated into three groups based on nidus size (S1: < 3 cm, S2: 3-6 cm, S3: > 6 cm) and age (A1: < 20 years, A2: 20-40 years, A3: > 40 years), followed by any combination of the combined supplemented grade: low risk (S1A1, S1A2, S2A1), intermediate risk (S2A2, S1A3, S3A1, or high risk (S3A3, S3A2, S2A3).

RESULTS

Two hundred forty-six patients had intermediate Supp-SM grade AVMs. Of these patients, 102 had Supp-SM grade 5 (41.5%), 99 had Supp-SM grade 6 (40.2%), and 45 had Supp-SM grade 7 (18.3%). Significant differences in the proportions of patients with worse mRS scores at follow-up were found between the groups, with 24.5% (25/102) of patients in Supp-SM grade 5, 29.3% (29/99) in Supp-SM grade 6, and 57.8% (26/45) in Supp-SM grade 7 (p < 0.001). Patients with Supp-SM grade 7 AVMs had significantly increased odds of worse postoperative mRS scores (p < 0.001; OR 3.7, 95% CI 1.9-7.3). In the expanded cohort of 349 Supp-SM grade 6 AVM patients, a significantly higher proportion of older patients with larger Supp-SM grade 6 AVMs (grade 6+, 38.6%) had neurological deterioration than the others with Supp-SM grade 6 AVMs (22.9%, p = 0.02). Conversely, in an expanded cohort of 197 Supp-SM grade 7 AVM patients, a significantly lower proportion of younger patients with smaller Supp-SM grade 7 AVMs (grade 7-, 19%) had neurological deterioration than the others with Supp-SM grade 7 AVMs (44.9%, p = 0.01).

CONCLUSIONS

Patients with Supp-SM grade 7 AVMs are at increased risk of worse postoperative neurological outcomes, making Supp-SM grade 6 an appropriate operability cutoff. However, young patients with small niduses in the low-risk Supp-SM grade 7 group (grade 7-) have favorable postoperative outcomes. Outcomes in Supp-SM grade 7 patients did not improve with surgeon experience, indicating that the operability boundary is a hard limit reflecting the complexity of high-grade AVMs.

Short and Long-term Outcomes of Subarachnoid Hemorrhage Treatment according to Hospital Volume in Korea: a Nationwide Multicenter Registry

BACKGROUND

Subarachnoid hemorrhage is a potentially devastating cerebrovascular attack with a high proportion of poor outcomes and mortality. Recent studies have reported decreased mortality with the improvement in devices and techniques for treating ruptured aneurysms and neurocritical care. This study investigated the relationship between hospital volume and short- and long-term mortality in patients treated with subarachnoid hemorrhage.

METHODS

We selected subarachnoid hemorrhage patients treated with clipping and coiling from March-May 2013 to June-August 2014 using data from Acute Stroke Registry, and the selected subarachnoid hemorrhage (SAH) patients were tracked in connection with data of Health Insurance Review and Assessment Service to evaluate the short-term and long-term mortality.

RESULTS

A total of 625 subarachnoid hemorrhage patients were admitted to high-volume hospitals (n = 355, 57%) and low-volume hospitals (n = 270, 43%) for six months. The mortality of SAH patients treated with clipping and coiling was 12.3%, 20.2%, 21.4%, and 24.3% at 14 days, three months, one year, and five years, respectively. The short-term and long-term mortality in high-volume hospitals was significantly lower than that in low-volume hospitals. On Cox regression analysis of death in patients with severe clinical status, low-volume hospitals had significantly higher mortality than high-volume hospitals during short-term follow-up. On Cox regression analysis in the mild clinical status group, there was no statistical difference between high-volume hospitals and low-volume hospitals.

CONCLUSION

In subarachnoid hemorrhage patients treated with clipping and coiling, low-volume hospitals had higher short-term mortality than high-volume hospitals. These results from a nationwide database imply that acute SAH should be treated by a skilled neurosurgeon with adequate facilities in a high-volume hospital.

Outcomes after clipping and endovascular coiling for aneurysmal subarachnoid hemorrhage among dual-eligible beneficiaries

Dual-eligible beneficiaries, individuals with both Medicare and Medicaid coverage, represent a high-cost and vulnerable population; however, literature regarding outcomes is sparse. We characterized outcomes in dual-eligible beneficiaries treated for aneurysmal subarachnoid hemorrhage (aSAH) compared to Medicare only, Medicaid only, private insurance, and self-pay. A 10-year cross-sectional study of the National Inpatient Sample was conducted. Adult aSAH emergency admissions treated by neurosurgical clipping or endovascular coiling were included. Multivariable regression was used to adjust for confounders. A total of 57,666 patients met inclusion criteria. Dual-eligibles comprised 2.8% of admissions and were on average younger (62.4 years) than Medicare (70.0 years), older than all other groups, and had higher mean National Inpatient Sample-Subarachnoid Hemorrhage Severity Scores than all other groups (p ≤ 0.001). Among patients treated by clipping, dual-eligibles were less often discharged to home compared to Medicare (adjusted odds ratio (aOR) = 0.51, 95% CI = 0.30-0.87, p < 0.05) and all other insurance groups, p < 0.01. Likewise, those who received coiling were less often discharged to home compared to Medicaid (aOR = 0.41, 95% CI = 0.23-0.73), private (aOR = 0.42, 95% CI = 0.23-0.76) and self-pay patients (aOR = 0.24, 95% CI = 0.12-0.46). They also had increased odds of poor National Inpatient Sample-Subarachnoid Hemorrhage Outcome Measures compared to Medicaid, private, and self-pay patients, all p < 0.05. There were no differences in inpatient mortality or total complications. In conclusion, dual-eligible patients had higher aSAH severity scores, less often discharged home, and among patients who received coiling, dual-eligibles had increased odds of poor outcome. Dual-eligible patients with aSAH represent a vulnerable population that may benefit from targeted clinical and public policy initiatives.

Clinical features, neurologic recovery, and risk factors of postoperative posterior fossa syndrome and delayed recovery: a prospective study

BACKGROUND

Posterior fossa syndrome (PFS) is a known consequence of medulloblastoma resection. Our aim was to clinically define PFS, its evolution over time, and ascertain risk factors for its development and poor recovery.

METHODS

Children with medulloblastoma treated at St Jude Children's Research Hospital from 6/2013 to 7/2019 received standardized neurological examinations, before and periodically after radiation therapy. Most (98.3%) were enrolled on the ongoing multi-institutional protocol (SJMB12; NCT01878617).

RESULTS

Sixty (34%) of 178 evaluated children had PFS. Forty (23%) had complete mutism (PFS1) and 20 (11%) had diminished speech (PFS2). All children with PFS had severe ataxia and 42.5% of PFS1 had movement disorders. By multivariable analysis, younger age (P = .0005) and surgery in a low-volume surgery center (P = .0146) increased PFS risk, while Sonic Hedgehog tumors had reduced risk (P = .0025). Speech and gait returned in PFS1/PFS2 children at a median of 2.3/0.7 and 2.1/1.5 months, respectively, however, 12 (44.4%) of 27 PFS1 children with 12 months of follow-up were nonambulatory at 1 year. Movement disorder (P = .037) and high ataxia score (P < .0001) were associated with delayed speech recovery. Older age (P = .0147) and high ataxia score (P < .0001) were associated with delayed gait return. Symptoms improved in all children but no child with PFS had normal neurologic examination at a median of 23 months after surgery.

CONCLUSIONS

Categorizing PFS into types 1 and 2 has prognostic relevance. Almost half of the children with PFS1 with 12-month follow-up were nonambulatory. Surgical experience was a major modifiable contributor to the development of PFS.

Predictors of Nonroutine Discharge Disposition Among Patients with Parasagittal/Parafalcine Meningioma

OBJECTIVE

Discharge disposition is an important outcome for neurosurgeons to consider in the context of high-quality, value-based care. There has been limited research into how the unique anatomic considerations associated with parasagittal/parafalcine meningioma resection may influence discharge disposition. We investigated the effects of various predictors on discharge disposition within a cohort of patients with parasagittal/parafalcine meningioma.

METHODS

A total of 154 patients treated at a single institution were analyzed (2016-2019). Bivariate analysis was conducted using the Mann-Whitney U and Fisher exact tests. Multivariate analysis was conducted using logistic regression. An optimism-corrected C-statistic was calculated using 2000 bootstrap samples to assess logistic regression model performance.

RESULTS

Our cohort was mostly female (67.5%) and white (72.7%), with a mean age of 57.29 years. Most patients had tumors associated with the middle third of the superior sagittal sinus (SSS) (60.4%) and had tumors that were not fully occluding the SSS (74.0%). In multivariate analysis, independent predictors of nonroutine discharge disposition included 5-factor Modified Frailty Index score (odds ratio [OR], 2.06; P = 0.0088), Simpson grade IV resection (OR, 4.22; P = 0.0062), and occurrence of any postoperative complication (OR, 2.89; P = 0.031). The optimism-corrected C-statistic of our model was 0.757.

CONCLUSIONS

In our single-institution experience, neither extent of SSS invasion nor location along the SSS predicted nonroutine discharge, suggesting that tumor invasion and posterior location along the SSS are not necessarily contraindications to surgery. Our results also highlight the importance of frailty and tumor size in stratifying patients at risk of nonroutine discharge disposition.

The state of neurosurgical training and education in East Asia: analysis and strategy development for this frontier of the world

OBJECTIVE

The authors, who are from Indonesia, Japan, Malaysia, the Philippines, and Taiwan, sought to illustrate the processes of training neurosurgeons in their respective settings by presenting data and analyses of the current state of neurosurgical education across the East Asian region.

METHODS

The authors obtained quantitative data as key indicators of the neurosurgical workforce from each country. Qualitative data analysis was also done to provide a description of the current state of neurosurgical training and education in the region. A strengths, weaknesses, opportunities, and threats (SWOT) analysis was also done to identify strategies for improvement.

RESULTS

The number of neurosurgeons in each country is as follows: 370 in Indonesia, 10,014 in Japan, 152 in Malaysia, 134 in the Philippines, and 639 in Taiwan. With a large neurosurgical workforce, the high-income countries Japan and Taiwan have relatively high neurosurgeon to population ratios of 1 per 13,000 and 1 per 37,000, respectively. In contrast, the low- to middle-income countries Indonesia, Malaysia, and the Philippines have low neurosurgeon to population ratios of 1 per 731,000, 1 per 210,000, and 1 per 807,000, respectively. In terms of the number of training centers, Japan has 857, Taiwan 30, Indonesia 7, Malaysia 5, and the Philippines 10. In terms of the number of neurosurgical residents, Japan has 1000, Taiwan 170, Indonesia 199, Malaysia 53, and the Philippines 51. The average number of yearly additions to the neurosurgical workforce is as follows: Japan 180, Taiwan 27, Indonesia 10, Malaysia 4, and the Philippines 3. The different countries included in this report have many similarities and differences in their models and systems of neurosurgical education. Certain important strategies have been formulated in order for the system to be responsive to the needs of the catchment population: 1) establishment of a robust network of international collaboration for reciprocal certification, skills sharing, and subspecialty training; 2) incorporation of in-service residency and fellowship training within the framework of improving access to neurosurgical care; and 3) strengthening health systems, increasing funding, and developing related policies for infrastructure development.

CONCLUSIONS

The varied situations of neurosurgical education in the East Asian region require strategies that take into account the different contexts in which programs are structured. Improving the education of current and future neurosurgeons becomes an important consideration in addressing the health inequalities in terms of access and quality of care afflicting the growing population in this region of the world.

Transsphenoidal Resection of Pituitary Tumors in the United States, 2009 to 2011: Effects of Hospital Volume on Postoperative Complications

Introduction  Higher surgical volumes correlate with superior patient outcomes for various surgical pathologies, including transnasal transsphenoidal (TNTS) pituitary tumor resection. With the introduction of endoscopic approaches, there have been nationwide shifts in technique with relative declines in microsurgery. We examined the volume-outcome relationship (VOR) for TNTS pituitary tumor surgery in an era of increasingly prevalent endoscopic approaches. Methods  Patients who underwent TNTS pituitary tumor resection between 2009 and 2011 were retrospectively identified in the State Inpatient Database subset of the Healthcare Cost and Utilization Project. Generalized linear mixed-effect models were used to assess odds of various outcome measures. Institutions were grouped into quartiles by case volume for analysis. Results  A total of 6,727 patients underwent TNTS pituitary tumor resection between 2009 and 2011. White or Asian American patients and those with private insurance were more likely to receive care at higher volume centers (HVC). Patients treated at HVC (>60 cases/year) were less likely to have nonroutine discharges (3.9 vs. 1.9%; p  = 0.002) and had shorter length of stay (LOS; 4 vs. 2 days; p  = 0.001). Overall, care at HVC trended toward lower rates of postoperative complications, for example, a 10-case/year increase correlated with a 10% decrease in the rate of iatrogenic panhypopituitarism (odds ratio [OR] = 0.90, 95% confidence interval [CI]: 0.81-0.99; p  = 0.04) and 5% decrease in likelihood of diabetes insipidus (OR = 0.95, 95% CI: 0.90-0.99; p  = 0.04) on multivariable analysis. Conclusions  Our analysis shows that increased case volume is related to superior perioperative outcomes for TNTS pituitary tumor resections. Despite the recent adoption of newer endoscopic techniques and concerns of technical learning curves, this VOR remains undisturbed.

Hospital teaching status associated with reduced inpatient mortality and perioperative complications in surgical neuro-oncology

PURPOSE

Studies have demonstrated that higher surgical volumes correlate with improved neurosurgical outcomes yet none exist evaluating the effects of hospital teaching status on the surgical neuro-oncology patient. We present the first analysis comparing brain tumor surgery perioperative outcomes at academic and non-teaching centers.

METHODS

Brain tumor surgeries in the Nationwide Inpatient Sample (NIS) from 1998 to 2014 were identified. A teaching hospital, defined by the NIS, must have ≥ 1 Accreditation Council of Graduate Medical Education (ACGME) approved residency programs, Council of Teaching Hospitals membership, or have a ratio ≥ 0.25 of full-time residents to hospital beds. Annual treatment trends were stratified by hospital teaching status, assessing yearly caseload with linear regression. Multivariable logistic regression determined predictors of inpatient mortality/complications. Hospitals were further divided into quartiles by case volume and teaching status was compared in each.

RESULTS

Teaching hospitals (THs) exhibited an average annual increase in brain tumor surgeries (+ 1057/year, p < 0.0001). In multivariable analysis, teaching status was associated with decreased risk of mortality (OR 0.82, p = 0.0003) and increased likelihood of discharge home (OR 1.21, p < 0.0001). In subgroup analysis, within the highest hospital quartile by caseload, higher mortality rates and lower routine discharges were again seen at non-teaching hospitals (NTHs) (p = 0.0002 and p = 0.0016, respectively).

CONCLUSION

THs are performing more brain tumor surgeries over time with lower rates of inpatient mortality and perioperative complications even after controlling for hospital case volume. These results suggest a shift in neuro-oncology practice patterns favoring THs to optimize patient outcomes especially at the highest volume centers.

Volume-outcome relationship in pediatric neurotrauma care: analysis of two national databases

OBJECTIVE

Previous research has demonstrated the association between increased hospital volume and improved outcomes for a wide range of neurosurgical conditions, including adult neurotrauma. The authors aimed to determine if such a relationship was also present in the care of pediatric neurotrauma patients.

METHODS

The authors identified 106,146 pediatric admissions for traumatic intracranial hemorrhage (tICH) in the National Inpatient Sample (NIS) for the period 2002–2014 and 34,017 admissions in the National Trauma Data Bank (NTDB) for 2012–2015. Hospitals were stratified as high volume (top 20%) or low volume (bottom 80%) according to their pediatric tICH volume. Then the association between high-volume status and favorable discharge disposition, inpatient mortality, complications, and length of stay (LOS) was assessed. Multivariate regression modeling was used to control for patient demographics, severity metrics, hospital characteristics, and performance of neurosurgical procedures.

RESULTS

In each database, high-volume hospitals treated over 60% of pediatric tICH admissions. In the NIS, patients at high-volume hospitals presented with worse severity metrics and more frequently underwent neurosurgical intervention over medical management (all p < 0.001). After multivariate adjustment, admission to a high-volume hospital was associated with increased odds of a favorable discharge (home or short-term facility) in both databases (both p < 0.001). However, there were no significant differences in inpatient mortality (p = 0.208). Moreover, high-volume hospital patients had lower total complications in the NIS and lower respiratory complications in both databases (all p < 0.001). Although patients at high-volume hospitals in the NTDB had longer hospital stays (β-coefficient = 1.17, p < 0.001), they had shorter stays in the intensive care unit (β-coefficient = 0.96, p = 0.024). To determine if these findings were attributable to the trauma center level rather than case volume, an analysis was conducted with only level I pediatric trauma centers (PTCs) in the NTDB. Similarly, treatment at a high-volume level I PTC was associated with increased odds of a favorable discharge (OR 1.28, p = 0.009), lower odds of pneumonia (OR 0.60, p = 0.007), and a shorter total LOS (β-coefficient = 0.92, p = 0.024).

CONCLUSIONS

Pediatric tICH patients admitted to high-volume hospitals exhibited better outcomes, particularly in terms of discharge disposition and complications, in two independent national databases. This trend persisted when examining level I PTCs exclusively, suggesting that volume alone may have an impact on pediatric neurotrauma outcomes. These findings highlight the potential merits of centralizing neurosurgery and pursuing regionalization policies, such as interfacility transport networks and destination protocols, to optimize the care of children affected by traumatic brain injury.

Increased complication and mortality among non-index hospital readmissions after brain tumor resection is associated with low-volume readmitting hospitals

OBJECTIVE

Fragmentation of care following craniotomy for tumor resection is increasingly common with the regionalization of neurosurgery. Hospital readmission to a hospital (non-index) other than the one from which patients received their original care (index) has been associated with increases in both morbidity and mortality for cancer patients. The impact of non-index readmission after surgical management of brain tumors has not previously been evaluated. The authors set out to determine rates of non-index readmission following craniotomy for tumor resection and evaluated outcomes following index and non-index readmissions.

METHODS

Retrospective analyses of data from cases involving resection of a primary brain tumor were conducted using data from the Nationwide Readmissions Database (NRD) for 2010-2014. Multivariate logistic regression was used to evaluate the independent association of patient and hospital factors with readmission to an index versus non-index hospital. Further analysis evaluated association of non-index versus index hospital readmission with mortality and major complications during readmission. Effects of readmission hospital procedure volume on mortality and morbidity were evaluated in post hoc analysis.

RESULTS

In a total of 17,459 unplanned readmissions, 84.4% patients were readmitted to index hospitals and 15.6% to non-index hospitals. Patient factors associated with increased likelihood of non-index readmission included older age (75+: OR 1.44, 95% CI 1.19-1.75), elective index admission (OR 1.19, 95% CI 1.08-1.30), increased Elixhauser comorbidity score ≥2 (OR 1.18, 95% CI 1.01-1.37), and malignant tumor diagnosis (OR 1.32, 95% CI 1.19-1.45) (all p < 0.04). Readmission to a non-index facility was associated with a 28% increase in major complications (OR 1.28, 95% CI 1.14-1.43, p < 0.001) and 21% increase in mortality (OR 1.21, 95% CI 1.02-1.44, p = 0.032) in initial analysis. Following a second multivariable logistic regression analysis including the readmitting hospital characteristics, low procedure volume of a readmitting facility was significantly associated with non-index readmission (p < 0.001). Readmission to a lower-procedure-volume facility was associated with a 46%-75% increase in mortality (OR 1.46-1.75, p < 0.005) and a 21%-35% increase in major complications (OR 1.21-1.34, p < 0.005). Following adjustment for volume at a readmitting facility, admission to a non-index facility was no longer associated with mortality (OR 0.90, 95% CI 0.71-1.14, p = 0.378) or major complications (OR 1.09, CI 0.94-1.26, p = 0.248).

CONCLUSIONS

Of patient readmissions following brain tumor resection, 15.6% occur at a non-index facility. Low procedure volume is a confounder for non-index analysis and is associated with an increased likelihood of major complications and mortality, as compared to readmission to high-procedure-volume hospitals. Further studies should evaluate interventions targeting factors associated with unplanned readmission.

Multiple Subpial Transections for Medically Refractory Epilepsy: A Disaggregated Review of Patient-Level Data

BACKGROUND

Multiple subpial transections (MST) are a treatment for seizure foci in nonresectable eloquent areas.

OBJECTIVE

To systematically review patient-level data regarding MST.

METHODS

Studies describing patient-level data for MST procedures were extracted from the Medline and PubMed databases, yielding a synthetic cohort of 212 patients from 34 studies. Data regarding seizure outcome, patient demographics, seizure type, surgery type, and complications were extracted and analyzed.

RESULTS

Seizure freedom was achieved in 55.2% of patients undergoing MST combined with resection, and 23.9% of patients undergoing MST alone. Significant predictors for seizure freedom were a temporal lobe focus (odds ratio 4.9; 95% confidence interval 1.71, 14.3) and resection of portions of the focus, when feasible (odds ratio 3.88; 95% confidence interval 2.02, 7.45). Complications were frequent, with transient mono- or hemiparesis affecting 19.8% of patients, transient dysphasia 12.3%, and permanent paresis or dysphasia in 6.6% and 1.9% of patients, respectively.

CONCLUSION

MST is an effective treatment for refractory epilepsy in eloquent cortex, with greater chances of seizure freedom when portions of the focus are resected in tandem with MST. The reported rates of seizure freedom with MST are higher than those of existing neuromodulatory therapies, such as vagus nerve stimulation, deep brain stimulation, and responsive neurostimulation, though these latter therapies are supported by randomized-controlled trials, while MST is not. The reported complication rate of MST is higher than that of resection and neuromodulatory therapies. MST remains a viable option for the treatment of eloquent foci, provided a careful risk-benefit analysis is conducted.

Trends in Routine and Complex Hepatobiliary Surgery Among General and Pediatric Surgical Residents: What is the Next Generation Learning and is it Enough?

OBJECTIVE

Previous studies reveal a correlation between surgical volume and outcomes; thus, a similar relationship likely exists between trainee operative volume and technical competence. While routine hepatobiliary surgery is commonplace, trainee exposure to the more advanced procedures may be lacking. We hypothesize that experience in complex hepatobiliary procedures may be deficient both during general surgery residency and pediatric surgery fellowship training.

DESIGN

Case log data from the ACGME were queried for general surgery residents (2000-2017) and pediatric surgery fellows (2004-2017). Laparoscopic cholecystectomy was considered a routine hepatobiliary procedure for both specialties. For general surgery, hepatic lobectomy/segmentectomy and choledochoenteric anastomosis were considered complex and for pediatric surgery, hepatic lobectomy, biliary atresia and choledochal cyst procedures were considered complex.

SETTING

Publicly available case log data from the ACGME.

PARTICIPANTS

General surgery residents and pediatric surgery fellows at ACGME-accredited training programs.

RESULTS

The number of trainees increased over the study period for both groups. Mean case volumes for laparoscopic cholecystectomy increased by 36% in surgery graduates and by 114% in pediatric surgery graduates. In surgery, the mean volumes for choledochoenteric anastomosis procedures decreased by 53% from 3.0 to 1.4 procedures/year with increasing variability in trainee experience. Volumes for hepatic lobectomy/segmentectomy increased by 68% from 3.4 to 5.7 procedures/year with decreasing variability. In pediatric surgery, case volumes for complex procedures were low (mean <4/year), highly variable among trainees, and appear unchanged between 2004 and 2017. In every year analyzed, at least 1 pediatric surgery trainee reported doing 0 cases in one of these complex categories.

CONCLUSIONS

Case logs suggest that the volume of complex hepatobiliary surgery remains low and highly variable in both disciplines with some trainees obtaining minimal or no exposure to certain cases. The relationship between these trends and the development of competency is worthy of further study.

The future of open vascular neurosurgery: perspectives on cavernous malformations, AVMs, and bypasses for complex aneurysms

Despite the erosion of microsurgical case volume because of advances in endovascular and radiosurgical therapies, indications remain for open resection of pathology and highly technical vascular repairs. Treatment risk, efficacy, and durability make open microsurgery a preferred option for cerebral cavernous malformations, arteriovenous malformations (AVMs), and many aneurysms. In this paper, a 21-year experience with 7348 cases was reviewed to identify trends in microsurgical management. Brainstem cavernous malformations (227 cases), once considered inoperable and managed conservatively, are now resected in increasing numbers through elegant skull base approaches and newly defined safe entry zones, demonstrating that microsurgical techniques can be applied in ways that generate entirely new areas of practice. Despite excellent results with microsurgery for low-grade AVMs, brain AVM management (836 cases) is being challenged by endovascular embolization and radiosurgery, as well as by randomized trials that show superior results with medical management. Reviews of ARUBA-eligible AVM patients treated at high-volume centers have demonstrated that open microsurgery with AVM resection is still better than many new techniques and less invasive approaches that are occlusive or obliterative. Although the volume of open aneurysm surgery is declining (4479 cases), complex aneurysms still require open microsurgery, often with bypass techniques. Intracranial arterial reconstructions with reimplantations, reanastomoses, in situ bypasses, and intracranial interpositional bypasses (third-generation bypasses) augment conventional extracranial-intracranial techniques (first- and second-generation bypasses) and generate innovative bypasses in deep locations, such as for anterior inferior cerebellar artery aneurysms. When conventional combinations of anastomoses and suturing techniques are reshuffled, a fourth generation of bypasses results, with eight new types of bypasses. Type 4A bypasses use in situ suturing techniques within the conventional anastomosis, whereas type 4B bypasses maintain the basic construct of reimplantations or reanastomoses but use an unconventional anastomosis. Bypass surgery (605 cases) demonstrates that open microsurgery will continue to evolve. The best neurosurgeons will be needed to tackle the complex lesions that cannot be managed with other modalities. Becoming an open vascular neurosurgeon will be intensely competitive. The microvascular practice of the future will require subspecialization, collaborative team effort, an academic medical center, regional prominence, and a large catchment population, as well as a health system that funnels patients from hospital networks outside the region. Dexterity and meticulous application of microsurgical technique will remain the fundamental skills of the open vascular neurosurgeon.

What Does it Mean for a Surgeon to “Run Two Rooms”? A Comprehensive Literature Review of Overlapping and Concurrent Surgery Policies

The aim of this study was to review and analyze all of the “concurrent surgery” (CS) and “overlapping surgery” (OS) literature with the goal of: standardizing terminology, defining discrepancies in the literature and proposing solutions for the current challenges of regulating surgery to achieve maximal safety and efficiency. The CS and OS literature has grown exponentially over the past two years. Before this, there were no significant publications addressing this topic. There is an extremely wide variance on how “running two rooms” is defined and whether it should be permitted. These differences affect our patients’ perception of this practice. The literature lacks any comprehensive review of the topic and terminology. We performed a PubMed search to identify studies that considered the issue of OS. The terms “overlapping surgery”, “concurrent surgery”, and “simultaneous surgery” (SS) were used in the query. We then analyzed the publications identified. The literature contained 18 published studies analyzing OS safety between November 2016 and June 2018. Eight were neurosurgical studies, three were orthopedic, and the remaining seven articles were in other surgical specialties. A total of 1,207,155 surgical cases (range 250–>500,000 patients) were analyzed among the 18 studies. There were 57,880 (5.04%) OS cases. The OS rates in the individual studies ranged from 1.2 to 68 per cent (Table 1). Neurosurgical studies had the highest average OS rate of 54 per cent (range 37–68%), whereas the average OS rate in orthopedic surgery was 43 per cent (range 2.7–68%). Approximately one-third of the studies were multicenter investigations (27.7%). The studies measured more than 20 distinct outcomes, but there were only five outcomes that were included in the majority of the studies: mortality rates, reoperation rates, procedure length of time, readmission rates, and hospital length of stay. The current body of literature repeatedly demonstrates that OS is a safe and effective option when undertaken by experienced surgeons who practice it frequently. For successful OS, the Mandatory Attending Portion for two surgeries must not overlap and Unnecessary Anesthesia Time must be prohibited. Hospitals and surgical specialty organizations must implement policies to assure the safe practice of OS.

National trends in cerebral bypass surgery in the United States, 2002–2014

OBJECTIVE

Cerebral bypass procedures are microsurgical techniques to augment or restore cerebral blood flow when treating a number of brain vascular diseases including moyamoya disease, occlusive vascular disease, and cerebral aneurysms. With advances in endovascular therapy and evolving evidence-based guidelines, it has been suggested that cerebral bypass procedures are in a state of decline. Here, the authors characterize the national trends in cerebral bypass surgery in the United States from 2002 to 2014.

METHODS

Using the National (Nationwide) Inpatient Sample, the authors extracted for analysis the data on all adult patients who had undergone cerebral bypass as indicated by ICD-9-CM procedure code 34.28. Indications for bypass procedures, patient demographics, healthcare costs, and regional variations are described. Results were stratified by indication for cerebral bypass including moyamoya disease, occlusive vascular disease, and cerebral aneurysms. Predictors of inpatient complications and death were evaluated using multivariable logistic regression analysis.

RESULTS

From 2002 to 2014, there was an increase in the annual number of cerebral bypass surgeries performed in the United States. This increase reflected a growth in the number of cerebral bypass procedures performed for adult moyamoya disease, whereas cases performed for occlusive vascular disease or cerebral aneurysms declined. Inpatient complication rates for cerebral bypass performed for moyamoya disease, vascular occlusive disease, and cerebral aneurysm were 13.2%, 25.1%, and 56.3%, respectively. Rates of iatrogenic stroke ranged from 3.8% to 20.4%, and mortality rates were 0.3%, 1.4%, and 7.8% for moyamoya disease, occlusive vascular disease, and cerebral aneurysms, respectively. Multivariate logistic regression confirmed that cerebral bypass for vascular occlusive disease or cerebral aneurysm is a statistically significant predictor of inpatient complications and death. Mean healthcare costs of cerebral bypass remained unchanged from 2002 to 20014 and varied with treatment indication: moyamoya disease $38,406 ± $483, vascular occlusive disease $46,618 ± $774, and aneurysm $111,753 ± $2381.

CONCLUSIONS

The number of cerebral bypass surgeries performed for adult revascularization has increased in the United States from 2002 to 2014. Rising rates of surgical bypass reflect a greater proportion of surgeries performed for moyamoya disease, whereas bypasses performed for vascular occlusive disease and aneurysms are decreasing. Despite evolving indications, cerebral bypass remains an important surgical tool in the modern endovascular era and may be increasing in use. Stagnant complication rates highlight the need for continued interest in advancing available bypass techniques or technologies to improve patient outcomes.

Association between volume of surgery for acute hemorrhagic stroke and mortality

This study aimed to investigate the association between volume of surgery and mortality in relation to interventions for acute hemorrhagic stroke, namely craniotomy and trephination.We obtained data on acute hemorrhagic stroke patients for a 5-year period (2009-2013) from the Health Insurance Review and Assessment Service. Hospitals were classified into 3 categories according to volume of surgery (low, medium, high). To avoid intentionally setting a cutoff, we placed the hospitals in order from those with high volume of surgery to those with low volume of surgery and divided them into 3 groups (tertile) according to the number of patients. The covariates were age, sex, hemorrhagic stroke site, type of health insurance, intensive care unit admission, history of hypertension, and Charlson comorbidity index. Multiple logistic regression analysis was performed with statistical significance set at 5%.A total of 41,917 patients who underwent craniotomy (n = 20,982) or trephination (n = 20,935) for acute hemorrhagic stroke were analyzed according to hemorrhage site (subarachnoid and others). The results showed that mortality from acute hemorrhagic stroke decreased with increasing volume of surgery. For subarachnoid hemorrhage, the odds ratios of the medium- and high-volume surgery groups were significantly lower (0.74 and 0.59, respectively) for mortality within 7 days of admission, and were also significantly lower (0.78 and 0.68) for mortality within 30 days of admission than that of the low-volume surgery group. The results for other hemorrhage sites were similar. The association between mortality and volume of surgery was more evident in the craniotomy group. Although this study was limited to a single country (South Korea), it partially addressed the shortcomings of previous studies by analyzing a nationwide database and examining all types of hemorrhagic strokes.

Cranial Tumor Surgical Outcomes at a High-Volume Academic Referral Center

OBJECTIVE

To determine adverse event rates for adult cranial neuro-oncologic surgeries performed at a high-volume quaternary academic center and assess the impact of resident participation on perioperative complication rates.

PATIENTS AND METHODS

All adult patients undergoing neurosurgical intervention for an intracranial neoplastic lesion between January 1, 2009, and December 31, 2013, were included. Cases were categorized as biopsy, extra-axial/skull base, intra-axial, or transsphenoidal. Complications were categorized as neurologic, medical, wound, mortality, or none and compared for patients managed by a chief resident vs a consultant neurosurgeon.

RESULTS

A total of 6277 neurosurgical procedures for intracranial neoplasms were performed. After excluding radiosurgical procedures and pediatric patients, 4151 adult patients who underwent 4423 procedures were available for analysis. Complications were infrequent, with overall rates of 9.8% (435 of 4423 procedures), 1.7% (73 of 4423), and 1.4% (63 of 4423) for neurologic, medical, and wound complications, respectively. The rate of perioperative mortality was 0.3% (14 of 4423 procedures). Case performance and management by a chief resident did not negatively impact outcome.

CONCLUSION

In our large-volume brain tumor practice, rates of complications were low, and management of cases by chief residents in a semiautonomous manner did not negatively impact surgical outcomes.

Quality Programs in Neurosurgery: The Memorial Hermann/University of Texas Experience

The importance of outcome measures is steadily increasing due to the rise of "pay for performance" and the advent of population health. In 2007, a quality initiative was started due to poor performance on rankings such as the University Health Consortium (UHC) report card. Inherent to all such efforts are common challenges: how to engage the providers; how to gather and ensure the accuracy of the data; how to attribute results to individuals; how to ensure permanent improvements. After analysis, a strategy was developed that included an initial focus on 3 metrics (mortality, infection rates, and complications), leadership from practicing neurosurgeons, protocol development and adherence, and subspecialization. In addition, it was decided that the metrics would initially apply to attending physicians only, but that the entire team would need to be involved. Once the fundamental elements were established, the process could be extended to other measures and providers. To support this effort, special information system tools were developed and a support team formed. As the program matured, measured outcomes improved and more metrics were added (to a current total of 48). For example, UHC mortality ratios (observed over expected) decreased by 75%. Infection rates decreased 80%. The program now involves all trainee physicians, advanced practice providers, nurses, and other staff. This paper describes the design, implementation, and results of this effort, and provides a practical guide that may be useful to other groups undertaking similar initiatives.

Quantifying Geographic Variation in Health Care Outcomes in the United States before and after Risk-Adjustment

BACKGROUND

Despite numerous studies of geographic variation in healthcare cost and utilization at the local, regional, and state levels across the U.S., a comprehensive characterization of geographic variation in outcomes has not been published. Our objective was to quantify variation in US health outcomes in an all-payer population before and after risk-adjustment.

METHODS AND FINDINGS

We used information from 16 independent data sources, including 22 million all-payer inpatient admissions from the Healthcare Cost and Utilization Project (which covers regions where 50% of the U.S. population lives) to analyze 24 inpatient mortality, inpatient safety, and prevention outcomes. We compared outcome variation at state, hospital referral region, hospital service area, county, and hospital levels. Risk-adjusted outcomes were calculated after adjusting for population factors, co-morbidities, and health system factors. Even after risk-adjustment, there exists large geographical variation in outcomes. The variation in healthcare outcomes exceeds the well publicized variation in US healthcare costs. On average, we observed a 2.1-fold difference in risk-adjusted mortality outcomes between top- and bottom-decile hospitals. For example, we observed a 2.3-fold difference for risk-adjusted acute myocardial infarction inpatient mortality. On average a 10.2-fold difference in risk-adjusted patient safety outcomes exists between top and bottom-decile hospitals, including an 18.3-fold difference for risk-adjusted Central Venous Catheter Bloodstream Infection rates. A 3.0-fold difference in prevention outcomes exists between top- and bottom-decile counties on average; including a 2.2-fold difference for risk-adjusted congestive heart failure admission rates. The population, co-morbidity, and health system factors accounted for a range of R2 between 18-64% of variability in mortality outcomes, 3-39% of variability in patient safety outcomes, and 22-70% of variability in prevention outcomes.

CONCLUSION

The amount of variability in health outcomes in the U.S. is large even after accounting for differences in population, co-morbidities, and health system factors. These findings suggest that: 1) additional examination of regional and local variation in risk-adjusted outcomes should be a priority; 2) assumptions of uniform hospital quality that underpin rationale for policy choices (such as narrow insurance networks or antitrust enforcement) should be challenged; and 3) there exists substantial opportunity for outcomes improvement in the US healthcare system.

The Volume-Outcome Effect: Impact on Trial-to-Permanent Conversion Rates in Spinal Cord Stimulation

OBJECTIVES

Conversion rates from trial leads to permanent spinal cord stimulation (SCS) systems have important implications for healthcare resource utilization (HCRU) and pain management. We hypothesized that there is a volume-outcome effect, with chronic pain patients who visit high volume SCS implanters will have higher trial-to-permanent conversion rates.

MATERIALS AND METHODS

We designed a large, retrospective analysis using the Truven MarketScan database analyzing adult SCS patients with provider information available, with or without IPG implantation from the years 2007 to 2012 was designed. Patients were divided into three provider-based groups: high (>25), medium (9-24), and low (3-8) volume providers. Univariate and multivariate models identified factors associated with successful conversion.

RESULTS

A total of 17,850 unique trial implants were performed by 3028 providers. Of 13,879 patients with baseline data available, 8981 (64.7%) progressed to permanent SCS. Higher volume providers were associated with slightly higher conversion rates (65.9% vs. 63.3% low volume, p = 0.029), explant rates (9.2% vs. 7.7% medium volume, p = 0.026), younger age (52.0 ± 13.4 years vs. 53.0 ± 13.4 years, p = 0.0026), Medicare/Medicaid (47.8% vs. 35.0% low volume, p < 0.0001), Southern region (53.5% vs. 38.9% low volume, p < 0.0001), and higher Charlson comorbidity scores (1.0 [SD = 1.4], p = 0.0002). Multivariate regression results showed female gender (1.13 [95% CI: 1.05-1.22], p < 0.001) and high volume providers associated with higher odds of successful trial conversion (1.12 [95% CI: 1.02-1.22], p = 0.014).

CONCLUSIONS

In this nationwide analysis, high volume providers achieved higher trial-to-permanent SCS conversion rates than lower volume providers. The study has implications for both training requirements and referral patterns to delineate minimum implant experience necessary for provider proficiency. Future studies may be useful to understand HCRU differences.

An unexpectedly high rate of revisions and removals in deep brain stimulation surgery: Analysis of multiple databases

INTRODUCTION

Deep brain stimulation (DBS) is an established therapy for movement disorders, and is under active investigation for other neurologic and psychiatric indications. While many studies describe outcomes and complications related to stimulation therapies, the majority of these are from large academic centers, and results may differ from those in general neurosurgical practice.

METHODS

Using data from both the Centers for Medicare and Medicaid Services (CMS) and the National Surgical Quality Improvement Program (NSQIP), we identified all DBS procedures related to primary placement, revision, or removal of intracranial electrodes. Cases of cortical stimulation and stimulation for epilepsy were excluded.

RESULTS

Over 28,000 cases of DBS electrode placement, revision, and removal were identified during the years 2004-2013. In the Medicare dataset, 15.2% and of these procedures were for intracranial electrode revision or removal, compared to 34.0% in the NSQIP dataset. In NSQIP, significant predictors of revision and removal were decreased age (odds ratio (OR) of 0.96; 95% CI: 0.94, 0.98) and higher ASA classification (OR 2.41; 95% CI: 1.22, 4.75). Up to 48.5% of revisions may have been due to improper targeting or lack of therapeutic effect.

CONCLUSION

Data from multiple North American databases suggest that intracranial neurostimulation therapies have a rate of revision and removal higher than previously reported, between 15.2 and 34.0%. While there are many limitations to registry-based studies, there is a clear need to better track and understand the true prevalence and nature of such failures as they occur in the wider surgical community.

Predictors of Variation in Neurosurgical Supply Costs and Outcomes Across 4904 Surgeries at a Single Institution

BACKGROUND

There is high variability in neurosurgical costs, and surgical supplies constitute a significant portion of cost. Anecdotally, surgeons use different supplies for various reasons, but there is little understanding of how supply choices affect outcomes. Our goal is to evaluate the effect of patient, procedural, and provider factors on supply cost and to determine if supply cost is associated with patient outcomes.

METHODS

We obtained patient information (age, gender, payor, case mix index [CMI], body mass index, admission source), procedural data (procedure type, length, date), provider information (name, case volume), and total surgical supply cost for all inpatient neurosurgical procedures from 2013 to 2014 at our institution (n = 4904). We created mixed-effect models to examine the effect of each factor on surgical supply cost, 30-day readmission, and 30-day mortality.

RESULTS

There was significant variation in surgical supply cost between and within procedure types. Older age, female gender, higher CMI, routine/elective admission, longer procedure, and larger surgeon volume were associated with higher surgical supply costs (P < 0.05). Routine/elective admission and higher surgeon volume were associated with lower readmission rates (odds ratio, 0.707, 0.998; P < 0.01). Only patient factors of older age, male gender, private insurance, higher CMI, and emergency admission were associated with higher mortality (odds ratio, 1.029, 1.700, 1.692, 1.080, 2.809). There was no association between surgical supply cost and readmission or mortality (P = 0.307, 0.548).

CONCLUSIONS

A combination of patient, procedural, and provider factors underlie the significant variation in neurosurgical supply costs at our institution. Surgical supply costs are not correlated with 30-day readmission or mortality.

Rate and complications of adult epilepsy surgery in North America: Analysis of multiple databases

Epilepsy surgery is under-utilized, but recent studies reach conflicting conclusions regarding whether epilepsy surgery rates are currently declining, increasing, or remaining steady. However, data in these prior studies are biased toward high-volume epilepsy centers, or originate from sources that do not disaggregate various procedure types. All major epilepsy surgery procedures were extracted from the Centers for Medicare and Medicaid Services Part B National Summary Data File and the American College of Surgeons National Surgical Quality Improvement Program. Procedure rates, trends, and complications were analyzed, and patient-level predictors of postoperative adverse events were identified. Between 2000-2013, 6200 cases of epilepsy surgery were identified. Temporal lobectomy was the most common procedure (59% of cases), and most did not utilize electrocorticography (63-64%). Neither temporal nor extratemporal lobe epilepsy surgery rates changed significantly during the study period, suggesting no change in utilization. Adverse events, including major and minor complications, occurred in 15.3% of temporal lobectomies and 55.6% of hemispherectomies. Our findings suggest stagnant rates of both temporal and extratemporal lobe epilepsy surgery across U.S. surgical centers over the past decade. This finding contrasts with prior reports suggesting a recent dramatic decline in temporal lobectomy rates at high-volume epilepsy centers. We also observed higher rates of adverse events when both low- and high-volume centers were examined together, as compared to reports from high-volume centers alone. This is consistent with the presence of a volume-outcome relationship in epilepsy surgery.

Clinical management of pineal cysts: a worldwide online survey

BACKGROUND

A pineal cyst is a benign affection of a pineal gland on the borderline between a pathological lesion and a variant of normality. Clinical management of patients with a pineal cyst remains controversial, especially when patients present with non-specific symptoms.

METHODS

An online questionnaire consisting of 13 questions was completed by 110 neurosurgeons worldwide. Responses were entered into a database and subsequently analysed.

RESULTS

Based on data from the questionnaire, the main indication criteria for pineal cyst resection are hydrocephalus (90 % of the respondents), Parinaud's syndrome (80 %) and growth of the cyst (68 %). Only 15 % of the respondents occasionally operate on patients with non-specific symptoms. If surgery is indicated, improvement is expected in 88 % of the patients. The vast majority of the respondents favour a supracerebellar infratentorial approach to the pineal region. Most (78 %) of the respondents regarded the patient registry as a potentially useful instrument.

CONCLUSIONS

This survey sheds light on the current practice of pineal cyst management across the world. Most of the respondents perform surgery on pineal cysts only if patients are presenting with symptoms attributable to a mass effect. Surgery for patients with non-specific complaints (headache, vertigo) is not widely accepted, although it may prove effective. A prospective patient registry might be useful in the decision-making process in the clinical management of pineal cysts.

High Subarachnoid Hemorrhage Patient Volume Associated With Lower Mortality and Better Outcomes

BACKGROUND

High-volume centers have better outcomes than low-volume centers when managing complex conditions including subarachnoid hemorrhage (SAH).

OBJECTIVE

To quantify SAH volume-outcome association and determine the extent to which this association is influenced by aggressiveness of care.

METHODS

A serial cross-sectional retrospective study using the Nationwide Inpatient Sample for 2002 to 2010 was performed. Included were all adult (older than 18 years of age) discharged patients with a primary diagnosis of SAH admitted from the emergency department or transferred to a discharging hospital; cases of trauma or arteriovenous malformation were excluded. Survey-weighted descriptive statistics estimated temporal trends. Multilevel logistic regression estimated volume-outcome associations for inpatient mortality and discharge home. Models were adjusted for demographic characteristics, year, transfer status, insurance status, all individual Charlson comorbidities, intubation, and all patient-refined, diagnosis-related group mortality. Analyses were repeated, excluding cases in which aggressive care was not pursued.

RESULTS

A total of 32,336 discharges were included; 13,398 patients underwent clipping (59.1%) or coiling (40.9%). The inpatient mortality rate decreased from 32.2% in 2002 to 22.2% in 2010; discharge home increased from 28.5% to 40.8% during the same period. As SAH volume decreased from 100/year, the mortality rate increased from 18.7% to 19.8% at 80/year, 21.7% at 60/year, 24.5% at 40/year, and 28.4% at 20/year. As SAH patient volume decreased, the probability of discharge home decreased from 40.3% at 100/year to 38.7% at 60/year, and 35.3% at 20/year. Better outcomes persisted in patients receiving aggressive care and in those not receiving aggressive care.

CONCLUSION

Short-term SAH outcomes have improved. High-volume hospitals have more favorable outcomes than low-volume hospitals. This effect is substantial, even for hospitals conventionally classified as high volume.