Predictors of Surgical Site Infection After Nonemergent Craniotomy: A Nationwide Readmission Database Analysis

Incidence and Risk Factors of Surgical Site Infection After Cranial Surgery for Patients with Brain Tumors: A Systematic Review and Meta-analysis

BACKGROUND

Surgical site infections after craniotomy (SSI-CRANs) are a serious adverse event given the proximity of the wound to the central nervous system. SSI-CRANs are associated with substantial patient morbidity and mortality. Despite the importance and recognition of this event in other surgical fields, there is a paucity of evidence in the neurosurgical literature devoted to SSI-CRAN specifically in patients after brain tumor surgery.

METHODS

Systematic searches of Medline, Embase, and Cochrane Central were undertaken. The primary outcome was the incidence of SSI-CRAN at 30 and 90 days. Secondary outcomes were risk factors for SSI-CRAN.

RESULTS

Thirty-seven studies reporting 91,907 patients with brain tumors who underwent cranial surgery were included in the meta-analysis. Pooled incidence of SSI-CRAN at 30 and 90 days was 4.03% (95% CI: 2.94%-5.28%, I2 = 97.3) and 6.17% (95% CI: 3.16%-10.07%, I2 = 97.3), respectively. Specifically, incidence of SSI-CRAN following surgery for posterior fossa tumors was the highest at 9.67% (95% CI: 5.98%-14.09%, I2 = 75.5). Overall pooled incidence of readmission within 30 days and reoperation due to SSI-CRAN were 13.9% (95% CI: 12.5%-15.5%, I2 = 0.0) and 16.3% (95% CI: 5.4%-31.3%, I2 = 72.9), respectively. Risk factors for SSI-CRAN included reintervention (risk ratio [RR] 1.58, 95% CI: 1.22-2.04, I2 = 0.0), previous radiotherapy (RR 1.69, 95% CI: 1.20-2.38, I2 = 0.0), longer duration of operation (mean difference 64.18, 95% CI: 3.96-124.40 minutes, I2 = 90.3) and cerebrospinal fluid (CSF) leaks (RR 14.26, 95% CI: 2.14-94.90, I2 = 73.2).

CONCLUSIONS

SSI-CRAN affects up to 1 in 14 patients with brain tumors. High-risk groups include those with reintervention, previous radiotherapy, longer duration of operation, and CSF leaks. Further prospective studies should focus on bundles of care that will reduce SSI-CRAN.

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.

Scalp wound management: a narrative review from a neurosurgical perspective

OBJECTIVE

This article aims to present a narrative review of current literature about the anatomical characteristics of the scalp as well as current practices in the management of surgical, traumatic and pressure injuries in the scalp, which are common in neurosurgery practice.

METHOD

We searched PubMed for publications and book chapters in English from 2011 to 2021. We also included commonly referenced papers that we considered relevant to the subject with publication before these dates. We used the search terms 'laceration,' and/or 'neurosurgery' and/or, 'pressure injury,' and/or 'craniotomy,' and/or 'surgical incision' in combination with 'scalp,' and/or 'wound care.' We also searched the reference lists of publications identified by the search strategy and selected those that we judged relevant.

RESULTS

We pre-selected 52 articles that covered various aspects of anatomy, pathophysiology, scalp wound management, or general wound care that we considered applied to the anatomical region of our interest. After abstract review, we selected 34 articles that met our search criteria and were included in our review.

CONCLUSION

There is limited evidence regarding classification and care of scalp wounds. As a result, many of the current practices for scalp wound management are based on evidence derived from studies involving different anatomical regions, not considering its particular anatomy, vasculature and microbiome. Further research is needed for more comprehensive and effective protocols for the management of scalp injuries. However, this present review proposes responses to the identified gaps concerning the management of scalp wounds.

Risk and protective factors associated with wound infection after neurosurgical procedures: A meta-analysis

To systematically evaluate the risk factors for wound infection at the surgical site after neurosurgical craniotomy by meta-analysis, and to provide an evidence-based basis for preventing the occurrence of wound infection. A computerised search of PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure and Wanfang database was conducted for relevant studies on risk factors for surgical site wound infection after neurosurgical craniotomy published from the database inception to November 2023. Two researchers independently screened the literature, extracted the data and performed quality assessment in strict accordance with the inclusion and exclusion criteria. STATA 17.0 software was applied for data analysis. Overall, 18 papers with 17 608 craniotomy patients were included, of which 905 patients developed wound infections. The analysis showed that underlying diseases [OR = 2.50, 95% CI (1.68, 3.72), p < 0.001] and emergency surgery [OR = 2.47, 95% CI (1.80, 3.38), p < 0.001] were the risk factors for developing wound infections after craniotomy, age < 60 years [OR = 0.72, 95% CI (0.52, 0.98), p = 0.039] was a protective factor for wound infections; whereas sex [OR = 1.11, 95% CI (0.98, 1.27), p = 0.112] and the antimicrobial use [OR = 1.30, 95% CI (0.81 2.09), p = 0.276] were not associated with the presence or absence of wound infection after craniotomy. Underlying disease and emergency surgery are risk factors for developing wound infections after craniotomy, whereas age < 60 years is a protective factor. Clinicians can reduce the occurrence of postoperative wound infections by communicating with patients in advance about the possibility of postoperative wound infections based on these factors, and by doing a good job of preventing postoperative wound infections.

Effect of preoperative hospital stay on surgical site infection in Chinese cranial neurosurgery

OBJECTIVE

Surgical site infection(SSI)after neurosurgical procedure can be devastating. Delayed hospital stay has been identified as a potentially modifiable driver of SSI in general surgery patients. However, the relationship between preoperative length of stay and SSI has not been quantified previously in neurosurgery. This study aimed to clarify the association.

DESIGN

A Cohort study based on STROBE checklist.

METHOD

This observational study focused on cranial neurosurgery patients at a tertiary referral centers in China. Data collection from hospital information system conducted between 1 January 2016 and 31 December 2016 was used to examine the results of interest (n = 600). Logistic regression analysis explored association between preoperative length of stay and SSI, adjusting for potential confounders.

RESULTS

Overall SSI prevalence was 10.8% and was significantly higher in the longer preoperative length of stay group. Besides preoperative length of stay, American Society of Anesthesiologists score, type of surgery, gross blood loss also significantly associated with SSI prevalence. Compared with 1 to 2 days, longer preoperative length of stay was associated with increased SSI prevalence after adjustment for confounders (3 to 4 days: odds ratio[OR], 0.975[95%CI, 0.417 to 2.281]; 5 to 6 days: OR, 2.830[95%CI, 1.092 to 7.332]; 7 or more days: OR, 4.039[95%CI, 1.164 to 14.015]; P for trend < 0.001). On the other hand, we found a positive association between preoperative length of stay to deep/space-organ SSI (OR = 1.404; 95% CI: 1.148 to 1.717; P for trend < 0.001), which was higher than superficial SSI (OR = 1.242; 95% CI: 0.835 to1.848; P for trend= 0.062).

CONCLUSIONS

In a cohort of patients from a single center retrospective surgical registry, a longer preoperative length of stay was associated with a higher incidence of cranial neurosurgical SSI. There is room for improvement in preoperative length of stay. This can be used for hospital management and to stratify patients with regard to SSI risk.

Construction and validation of infection risk model for patients with external ventricular drainage: a multicenter retrospective study

PURPOSE

External ventricular drainage (EVD) is a life-saving neurosurgical procedure, of which the most concerning complication is EVD-related infection (ERI). We aimed to construct and validate an ERI risk model and establish a monographic chart.

METHODS

We retrospectively analyzed the adult EVD patients in four medical centers and split the data into a training and a validation set. We selected features via single-factor logistic regression and trained the ERI risk model using multi-factor logistic regression. We further evaluated the model discrimination, calibration, and clinical usefulness, with internal and external validation to assess the reproducibility and generalizability. We finally visualized the model as a nomogram and created an online calculator (dynamic nomogram).

RESULTS

Our research enrolled 439 EVD patients and found 75 cases (17.1%) had ERI. Diabetes, drainage duration, site leakage, and other infections were independent risk factors that we used to fit the ERI risk model. The area under the receiver operating characteristic curve (AUC) and the Brier score of the model were 0.758 and 0.118, and these indicators' values were similar when internally validated. In external validation, the model discrimination had a moderate decline, of which the AUC was 0.720. However, the Brier score was 0.114, suggesting no degradation in overall performance. Spiegelhalter's Z-test indicated that the model had adequate calibration when validated internally or externally (P = 0.464 vs. P = 0.612). The model was transformed into a nomogram with an online calculator built, which is available through the website: https://wang-cdutcm.shinyapps.io/DynNomapp/ .

CONCLUSIONS

The present study developed an infection risk model for EVD patients, which is freely accessible and may serve as a simple decision tool in the clinic.

Perioperative Means to Prevent Surgical Site Infections following Elective Craniotomies: A Single-Center Experience

Background  Postoperative surgical site infections are a recognized complication following craniotomies with an associated increase in morbidity and mortality. Several studies have attempted to identify bundles of care to reduce the incidence of infections. Our study aims to clarify which perioperative measures play a role in reducing surgical infection rates further. Methods  This study is a retrospective audit of all elective craniotomies in years 2018 to 2019. The primary endpoint was the surgical site infection rate at 30 days and 4 months after the procedure. Univariate analysis was used to identify factors predictive of postoperative infection. Results  344 patients were included in this study. Postoperative infections were observed in 5.2% of our cohort. No postoperative infections occurred within 4 months in patients receiving perioperative hair wash and intrawound vancomycin powder. In univariate analysis, craniotomy size (Fisher's exact test, p  = 0.05), lack of perioperative hair wash, and vancomycin powder use (Fisher's exact test, p  = 0.01) were predictive of postoperative infection. No complications relative to the use of intrawound vancomycin were observed. Conclusion  Our study demonstrates that simple measures such as perioperative hair wash combined with intrawound vancomycin powder in addition to standard practice can help reducing infection rates with negligible risks and acceptable costs. Our results should be validated further in future prospective studies.

Surgical Site Infections in Glioblastoma Patients-A Retrospective Analysis

Surgical site infections (SSIs) after craniotomy lead to additional morbidity and mortality for patients, which are related to higher costs for the healthcare system. Furthermore, SSIs are associated with a longer hospital stay for the patient, which is particularly detrimental in glioblastoma patients due to their limited life expectancy. Risk factors for SSIs have already been described for craniotomies in general. However, there is limited data available for glioblastoma patients. As postoperative radiation influences wound healing, very early radiation is suspected to be a risk factor for SSI. Nevertheless, there are no data on the optimal timing of radiotherapy. To define risk factors for these patients, we analyzed our collective. We performed a retrospective analysis of all operations with histological evidence of a glioblastoma between 2012 and 2021. Open biopsy and tumor removal (gross total resection, subtotal resection) were included. Stereotactic biopsies were excluded. Demographic data such as age and gender, as well as duration of surgery, diameter of the trepanation, postoperative radiation with interval, postoperative chemotherapy, highest blood glucose level, previous surgery, ASA score, foreign material introduced, subgaleal suction drainage, ventricle opening and length of hospital stay, were recorded. The need for surgical revision due to infection was registered as an SSI. A total of 177 patients were included, of which 14 patients (7.9%) suffered an SSI. These occurred after a median of 45 days. The group with SSIs tended to include more men (57.1%, p = 0.163) and more pre-operated patients (50%, p = 0.125). In addition, foreign material and subgaleal suction drains had been implanted more frequently and the ventricles had been opened more frequently, without reaching statistical significance. Surprisingly, significantly more patients without SSIs had been irradiated (80.3%, p = 0.03). The results enable a better risk assessment of SSIs in glioblastoma patients. Patients with previous surgery, introduced foreign material, subgaleal suction drain and opening of the ventricle may have a slightly higher for SSIs. However, because none of these factors were significant, we should not call them risk factors. A less radical approach to surgery potentially involving these factors is not justified. The postulated negative role of irradiation was not confirmed, hence a rapid chemoradiation should be induced to achieve the best possible oncologic outcome.

Associations of race and socioeconomic status with outcomes after intracranial meningioma resection: a systematic review and meta-analysis

PURPOSE

Social determinants of health broadly affect healthcare access and outcomes. Studies report that minorities and low socioeconomic status (SES) patients undergoing intracranial meningioma resection demonstrate worse outcomes and higher mortality rates. This systematic review and meta-analysis summarizes the available research reporting racial and SES disparities in intracranial meningioma resection outcomes.

METHODS

A systematic review was conducted using PRISMA guidelines and included peer-reviewed, English-language articles from the United States between 2000 and 2022 that reported racial and SES disparities in meningioma outcomes. Outcomes included overall survival (OS), extent of resection (EOR), hospitalization costs, length of stay (LOS), 30-day readmission, recurrence, and receipt of surgery and adjuvant radiotherapy. A quantitative meta-analysis was performed only on survival outcomes by race. All other variables were summarized as a systematic review.

RESULTS

633 articles were identified; 19 studies met inclusion criteria. Black or low SES patients were more likely to have increased hospitalization costs, rates of 30-day readmission, LOS, recurrence and less likely to undergo surgery, gross total resection, and adjuvant radiotherapy for their tumors. Six studies were used for the quantitative meta-analysis of race and OS. Compared to White patients, Black patients had significantly worse survival outcomes, and Asian patients had significantly better survival outcomes.

CONCLUSION

Disparities in outcomes exist for patients who undergo surgery for meningioma, such that Black and low SES patients have worse outcomes. The literature is quite sparse and contains confounding relationships not often accounted for appropriately. Further studies are needed to help understand these disparities to improve outcomes.

Comparison of Infection Rates Following Immediate and Delayed Cranioplasty for Postcraniotomy Surgical Site Infections: Results of a Meta-Analysis

Postoperative surgical site infections (SSIs) in neurosurgery are rare. However, they pose a formidable challenge to the treating neurosurgeon and substantially worsen patient outcomes. These infections require prompt intervention in the form of débridement, including removal of craniotomy bone. Reconstruction of the craniotomy defect can be performed along with the débridement or can be performed at a later time. Although there have been concerns about performing cranioplasty at the same time as débridement, recent studies have advocated performance of cranioplasty at the same time as the débridement, as it avoids the morbidity associated with having a craniectomy defect and avoids the need for another surgical procedure. We conducted a literature review and meta-analysis to examine the data on immediate cranioplasties and delayed cranioplasties performed for postcraniotomy SSIs. We analyzed 15 articles with a total of 353 patients. Our analysis revealed that the pooled proportion of treatment failure was 10.4% (95% confidence interval [CI] 5.9%-17.8%) when an immediate cranioplasty was done and 16.1% (95% CI 7.2%-32.1%) when delayed cranioplasty was done. The pooled proportion of treatment failure was 12% (95% CI 5.9%-22.9%) when the same bone was used for cranioplasty and was 8% (95% CI 3%-20%) when prosthetic material such as titanium was used for cranial vault reconstruction. Thus, the rate of treatment failure was less when an immediate single-stage cranioplasty was done compared with a delayed cranioplasty following SSIs.

Additive risk of surgical site infection from more than one risk factor following craniotomy for tumor

PURPOSE

This study seeks to expound upon risk factor etiologies for surgical site infection (SSI) and investigate their combinatorial effects on infection rate following craniotomy for neuro-oncologic pathology.

METHODS

Patients who underwent neuro-oncologic craniotomy between 2006 and 2020 were included. Medical records were reviewed to identify the occurrence of wound infection at ≤ 3 months postoperatively. Potential risk factors for infection included tumor pathology, location, anesthesia type, indication, ventricular entry, foreign body, brachytherapy, lumbar drain, prior operation, prior cranial radiation, prior infection, bevacizumab, and medical comorbidities (hypertension, obesity, diabetes, hyperlipidemia, other cancer, cirrhosis). Logistic regression was implemented to determine risk factors for SSI. Chi-square tests were used to assess whether the number of risk factors (e.g., 0, ≥ 1, ≥2, ≥ 3, ≥4) increases the risk of SSI compared to patients with fewer risk factors. The relative increase with each additional risk factor was also evaluated.

RESULTS

A total of 1209 patients were included. SSI occurred in 42 patients (3.5%) by 90 days after surgery. Significant risk factors on multivariate logistic regression were bevacizumab (OR 40.84; p < 0.001), cirrhosis (OR 14.20, p = 0.03), foreign body placement (OR 4.06; P < 0.0001), prior radiation (OR 2.20; p = 0.03), and prior operation (OR 1.92; p = 0.04). Infection rates in the combinatorial analysis were as follows: ≥1 risk factor = 5.9% (OR 2.74; p = 0.001), ≥ 2 = 6.7% (OR 2.28; p = 0.01), ≥ 3 = 19.0% (OR 6.5; p < 0.0001), ≥ 4 = 100% (OR 30.2; p < 0.0001).

CONCLUSIONS

Risk factors in aggregate incrementally increase the risk of postoperative SSI after craniotomy for tumor.

Immediate Titanium Mesh Cranioplasty After Debridement and Craniectomy for Postcraniotomy Surgical Site Infections and Risk Factors for Reoperation

BACKGROUND

We previously published a novel strategy for management of postcraniotomy bone flap infection consisting of single stage debridement, bone flap removal, and immediate titanium mesh cranioplasty.

METHODS

Postcraniotomy patients with surgical site infections treated with surgical debridement, bone flap removal, and immediate titanium mesh cranioplasty were retrospectively reviewed. The primary outcome measure was reoperation due to persistent infection or wound healing complications from the titanium mesh.

RESULTS

We included 48 patients, of which 15 (31.3%) were female. The most common primary diagnoses were glioblastoma (31.3%), meningioma (18.8%), and vascular/trauma (16.7%). Most patients had a history of same-site craniotomy prior to the surgery complicated by surgical site infection and 47.9% had prior cranial radiation. Thirty-six (75.0%) patients achieved resolution of their infection and did not require a second operation. Twelve (25.0%) patients required reoperation: 6 (12.5%) patients were found to have frank intraoperative purulence on reoperation, whereas 6 (12.5%) had reoperation for poor wound healing without any evidence of persistent infection. Cochran Armitage trend test revealed that patients with increasing number of wound healing risk factors had significantly higher risk of reoperation (P = 0.001). Prior intensity modulated radiotherapy alone was a significant risk factor for reoperation (6.5 [1.40-30.31], P = 0.002). Median follow-up time was 20.5 weeks.

CONCLUSIONS

Immediate titanium mesh cranioplasty at the time of debridement and bone flap removal is an acceptable option in the management of post-craniotomy bone flap infection. Patients with multiple wound healing risk factors are at higher risk for reoperation.

Risk factors for 90-day all-cause mortality in post-operative central nervous system infections (PCNSIs): A retrospective study of 99 patients in China

Post-operative central nervous system infections (PCNSIs) are serious complications of craniotomy. Many factors, including patient-related, surgical, and postoperative factors, affect the survival of patients with PCNSIs. Timely and effective implementation of antibiotics targeting pathogenic bacteria is crucial to reduce mortality. Metagenomic next-generation sequencing (mNGS) has been used successfully to detect pathogens associated with infectious diseases. This study was designed to evaluate the factors influencing mortality and to explore the application value of mNGS in patients with PCNSIs. We conducted a retrospective study of patients with PCNSIs in our unit from 1/12/2019 to 28/2/2021. Clinical data, cerebrospinal fluid (CSF) parameters, surgical information, and mNGS results were collected. Follow-up telephone calls were made in June 2021 for 90 days survival after discharge. 99 patients were enrolled, and the overall mortality rate was 36.4% (36/99). Kaplan-Meier survival analysis suggested that the risk factors for poor prognosis included age ≥ 53 years, Glasgow Coma scale (GCS) score ≤ 8, CSF/blood glucose ratio (C/B-Glu) ≤ 0.23, 2 or more operations, mechanical ventilation (MV), and non-mNGS test. MV and poor wound healing were independent risk factors for 90 day mortality according to the multivariate Cox proportional hazards model (OR = 6.136, P = .017, OR = 2.260, P = .035, respectively). Among the enrolled patients, causative pathogens were identified in 37. Gram-negative pathogens were found in 22 (59.5%) patients, and the remaining 15 (40.5%) were Gram-positive pathogens. Univariate analysis showed that white cell count and protein and lactate levels in the CSF of the Gram-negative group were higher than those of the Gram-positive group (P < .05). mNGS and conventional microbiological culture were tested in 34 patients, and the positive detection rate of mNGS was 52.9%, which was significantly higher than that of microbiological culture (52.9% vs 26.5%, χ2 = 4.54, P = .033). The mortality rate of PCNSIs is high, and patients with MV and poor wound healing have a higher mortality risk. Gram-negative pathogens were the predominant pathogens in the patients with PCNSIs. mNGS testing has higher sensitivity and has the potential to reduce the risk of mortality in patients with PCNSIs.

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.

Predictors of surgical site infection in glioblastoma patients undergoing craniotomy for tumor resection

OBJECTIVE

Surgical site infections (SSIs) burden patients and healthcare systems, often requiring additional intervention. The objective of this study was to identify the relationship between preoperative predictors inclusive of scalp incision type and postoperative SSI following glioblastoma resection.

METHODS

The authors retrospectively reviewed cases of glioblastoma resection performed at their institution from December 2006 to December 2019 and noted preoperative demographic and clinical presentations, excluding patients missing these data. Preoperative nutritional indices were available for a subset of cases. Scalp incisions were categorized as linear/curvilinear, reverse question mark, trapdoor, or frontotemporal. Patients were dichotomized by SSI incidence. Multivariable logistic regression was used to determine predictors of SSI.

RESULTS

A total of 911 cases of glioblastoma resection were identified, 30 (3.3%) of which demonstrated postoperative SSI. There were no significant differences in preoperative malnutrition or number of surgeries between SSI and non-SSI cases. The SSI cases had a significantly lower preoperative Karnofsky Performance Status (KPS) than the non-SSI cases (63.0 vs 75.1, p < 0.0001), were more likely to have prior radiation history (43.3% vs 26.4%, p = 0.042), and were more likely to have received steroids both preoperatively and postoperatively (83.3% vs 54.5%, p = 0.002). Linear/curvilinear incisions were more common in non-SSI than in SSI cases (56.9% vs 30.0%, p = 0.004). Trapdoor scalp incisions were more frequent in SSI than non-SSI cases (43.3% vs 24.2%, p = 0.012). On multivariable analysis, a lower preoperative KPS (OR 1.04, 95% CI 1.02–1.06), a trapdoor scalp incision (OR 3.34, 95% CI 1.37–8.49), and combined preoperative and postoperative steroid administration (OR 3.52, 95% CI 1.41–10.7) were independently associated with an elevated risk of postoperative SSI.

CONCLUSIONS

The study findings indicated that SSI risk following craniotomy for glioblastoma resection may be elevated in patients with a low preoperative KPS, a trapdoor scalp incision during surgery, and steroid treatment both preoperatively and postoperatively. These data may help guide future operative decision-making for these patients.

Nationwide Readmission Rates and Hospital Charges for Patients With Surgical Evacuation of Nontraumatic Subdural Hematomas: Part 1-Craniotomy

BACKGROUND

Despite patients experiencing high recurrence and readmission rates after surgical management of nontraumatic subdural hematomas (SDHs), few studies have examined the causes and predictors of unplanned readmissions in this population on a national scale.

OBJECTIVE

To analyze independent factors predicting 30-day hospital readmissions after surgical treatment of nontraumatic SDH in patients who survived their index surgery and evaluate hospital readmission rates and charges.

METHODS

Using the Nationwide Readmissions Database, we identified patients who underwent craniotomy for nontraumatic SDH evacuation (2010-2015) using a retrospective cohort observational study design. National estimates and variances within the cohort were calculated after stratifying, hospital clustering, and weighting variables.

RESULTS

Among 49 013 patients, 10 643 (21.7%) had at least 1 readmission within 30 days of their index treatment and 38 370 (78.3%) were not readmitted. Annual readmission rates did not change during the study period ( P = .74). The most common primary causes of 30-day readmissions were recurrent SDH (n = 3949, 37.1%), venous thromboembolism (n = 1373, 12.9%), and delayed hyponatremia and syndrome of inappropriate antidiuretic hormone secretion (n = 1363, 12.8%). Comorbidities that independently predicted readmission included congestive heart failure, chronic obstructive pulmonary disease, coagulopathy, diabetes mellitus, liver disease, lymphoma, fluid and electrolyte disorders, metastatic cancer, peripheral vascular disease, psychosis, and renal failure ( P ≤ .03). Household income in the 51st to 75th percentile was associated with a decreased risk of readmission.

CONCLUSION

National trends in 30-day readmission rates after nontraumatic SDH treatment by craniotomy provide quality benchmarks that can be used to drive quality improvement efforts on a national level.

Use of intraoperative MRI for resection of intracranial tumors: A nationwide analysis of short-term outcomes

OBJECTIVE

Recent evidence supports the use of intraoperative MRI (iMRI) during resection of intracranial tumors due to its demonstrated efficacy and clinical benefit. Though many single-center investigations have been conducted, larger nationwide outcomes have yet to be characterized.

METHODS

We used the American College of Surgeons National Surgical Quality Improvement Program database to examine baseline characteristics and 30-day postoperative outcomes among patients undergoing craniotomy for tumor resection with and without iMRI. Comparisons between outcomes were accomplished after propensity matching using chi-square tests for categorical variables and Welch two-sample t-tests for continuous variables.

RESULTS

A total of 38,003 patients met inclusion criteria. Of this population, 54 (0.1%) received iMRI, while 37,949 (99.9%) did not receive iMRI. After propensity score matching, the resulting groups consisted of an iMRI group (n = 54) and a matched non-iMRI group (n = 54). Procedures involving iMRI were associated with significantly increased operation length compared to those without (p < 0.01). Length of hospital stay was higher in patients without iMRI, with this difference trending towards significance (p = 0.05) in the unmatched comparison. Patients undergoing craniotomy without iMRI had a higher rate of readmission (p = 0.04). There was no significant difference in occurrence of other adverse events between the two patient groups.

CONCLUSION

Despite increasing operative length, iMRI is not associated with higher infection rate and may have a clinical benefit associated with reducing readmissions and a trend towards reducing inpatient length of stay. Additional nationwide analyses including more iMRI patients would provide further insight into the strength of these findings.

Does the use of surgical adjuncts affect post-operative infection rates in Neuro-oncology surgery?

BACKGROUND

Surgical site infection (SSI) is a significant cause of post-operative morbidity and mortality. As oncological care advances, the use of surgical adjuncts such as intraoperative US (Ultrasound), 5-ALA (5-Aminolevulinic acid) and neurophysiological monitoring has increased. This study set out to identify whether the use of surgical adjuncts in supratentorial tumour surgery lead to increased operative time or increased rates of SSI.

METHODS

This is a retrospective study at a large tertiary clinical neurosciences centre in the UK. We included all patients who underwent an elective supratentorial craniotomy for a tumour over a 12 month period. We retrospectively assessed whether patients had had a post-operative infection at 30 days or 4 months using our electronic patient record system.

RESULTS

267 patients were included. The median age was 58 years (range 17-87 years) with roughly equal numbers of males and females (males = 138/267, 52%). Most operations were carried out for gliomas (149/267, 56%) or metastases (61/267, 23%). The median length of surgery was 3 hours 6 minutes with 24% lasting >4 hours. The overall infection rate was 4.5%. Intraoperative monitoring and 5-ALA was associated with longer operative times although not necessarily larger craniotomy sizes whilst intraoperative US was associated with a shorter operative time and smaller craniotomy size. These adjuncts were not associated with an increased risk of infection.

CONCLUSION

This study adds reassurance that whilst some surgical adjuncts lead to increased operative times in our study there was no apparent increased risk of infection as a result of this.

Combined use of vancomycin powder and betadine irrigation lowers the incidence of postcraniotomy wound infection in low-risk cases: a single-center risk-stratified cohort analysis

PURPOSE

Postoperative surgical site infections (SSIs) constitute a significant source of morbidity for neurosurgical patients. Protocols that minimize postoperative wound infections are integral to improving outcomes and curtailing expenditures. The present study seeks to identify risk factors for infection and assess the efficacy of prophylactic betadine irrigation and vancomycin powder in addition to standard antibiotic irrigation.

METHODS

We reviewed craniotomies performed by THS at Weill Cornell/New York Presbyterian Hospital to treat neuro-oncologic pathology. Patients were divided into three groups: group 1 - antibiotic irrigation, group 2 - antibiotic irrigation and betadine irrigation, group 3 - antibiotic irrigation, betadine irrigation, and vancomycin powder. SSI was confirmed with bacterial culture. Risk factor identification and assessment of treatment paradigms was performed using chi-square tests and univariate logistic regression.

RESULTS

Among 1209 total patients, the 30- and 90-day SSI rates were 1.7% and 3.5%, respectively. Significant predictors of SSI included preoperative use of bevacizumab (OR 40.84; p < 0.0001), foreign body (OR 4.06; p < 0.0001), prior radiation (OR 2.20; p = 0.03), and prior operation/biopsy (OR 1.92; p = 0.04). Risk of infection was 2.1% in low-risk cases and 6.9% in high-risk cases. A significant, incremental decrement in SSIs was identified between the prophylaxis groups, although only among low-risk cases: group 1: 4.53%, group 2: 1.39%, group 3: 0.42% (p = 0.02). Neither vancomycin powder nor betadine significantly reduced the risk of SSI in patients with one or more risk factors.

CONCLUSION

Vancomycin powder with betadine irrigation decreased SSI rates following neuro-oncologic cranial procedures in patients at low risk of infection (i.e., no preoperative risk factors).

Nonemergent craniotomy surgical site infection: a retrospective cohort study

Background

The incidence of surgical site infection after craniotomy (SSI-CRAN) varies widely and is associated with major consequences. The aim of this study is to estimate the SSI-CRAN rate at the neurosurgery department of a tertiary center and to establish its risk factors.

Methods

All consecutive adult patients who underwent elective craniotomy for tumor resection at a tertiary center from January 2018 to October 2019 were retrospectively assessed. Demographic, clinical, and surgical data were collected. The main outcome of our study was the development of SSI within 30days postsurgery, as defined by the European Centre for Disease Prevention and Control guidelines. Univariate and multivariate analyses were performed to establish risk factors for SSI-CRAN.

Results

From the 271 patients enrolled in this study, 15 (5.5%) developed SSI-CRAN within 30days postsurgery, 11 (73.3%) of which were organ-space. The most common causative microorganisms isolated were gram-positive cocci, particularly Staphylococcus epidermidis (n = 4, 66.7%). In the univariate analysis, absence of normothermia and cerebrospinal fluid (CSF) leak were associated with SSI-CRAN. In the multivariate analysis, normothermia was the only protective factor and CSF leak was the only independent risk factor for SSI-CRAN.

Conclusion

The cumulative incidence of SSI-CRAN within 30days postsurgery was 5.5%. CSF leak and the absence of normothermia were the only independent risk factors for SSI-CRAN. The data provided in this study should be considered in the design of preventive strategies aimed to reduce the incidence of SSI.

Association of Diabetes Mellitus With Postoperative Complications and Mortality After Non-Cardiac Surgery: A Meta-Analysis and Systematic Review

BACKGROUND

Although a variety of data showing that diabetes mellitus (DM) (Type 1 or Type 2) is associated with postoperative complication, there is still a lack of detailed studies that go through the specific diabetic subgroups. The goal of this meta-analysis is to assess the relationship between DM and various complications after non-cardiac surgery.

METHODS

We searched articles published in three mainstream electronic databases (PubMed, EMBASE, Web of science) before November, 2020. A random effects model was conducted since heterogeneity always exist when comparing results between different types of surgery.

RESULTS

This paper included 125 studies with a total sample size of 3,208,776 participants. DM was a risk factor for any postoperative complication (Odds ratio (OR)=1.653 [1.487, 1.839]). The risk of insulin-dependent DM (OR=1.895 [1.331, 2.698]) was higher than that of non-insulin-dependent DM (OR=1.554 [1.061, 2.277]) for any postoperative complication. DM had a higher risk of infections (OR=1.537 [1.322, 1.787]), wound healing disorders (OR=2.010 [1.326, 3.046]), hematoma (OR=1.369 [1.120, 1.673]), renal insufficiency (OR=1.987 [1.311, 3.013]), myocardial infarction (OR=1.372 [0.574, 3.278]). Meanwhile, DM was a risk factor for postoperative reoperation (OR=1.568 [1.124, 2.188]), readmission (OR=1.404 [1.274, 1.548]) and death (OR=1.606 [1.178, 2.191]).

CONCLUSIONS

DM is a risk factor for any postoperative complications, hospitalization and death after non-cardiac surgery. These findings underscore the importance of preoperative risk factor assessment of DM for the safe outcome of surgical patients.

Systematic Review of Racial, Socioeconomic, and Insurance Status Disparities in Neurosurgical Care for Intracranial Tumors

BACKGROUND

The impact of race, socioeconomic status (SES), insurance status, and other social metrics on the outcomes of patients with intracranial tumors has been reported in several studies. However, these findings have not been comprehensively summarized.

METHODS

We conducted a PRISMA systematic review of all published articles between 1990 and 2020 that analyzed intracranial tumor disparities, including race, SES, insurance status, and safety-net hospital status. Outcomes measured include access, standards of care, receipt of surgery, extent of resection, mortality, complications, length of stay (LOS), discharge disposition, readmission rate, and hospital charges.

RESULTS

Fifty-five studies were included. Disparities in mortality were reported in 27 studies (47%), showing minority status and lower SES associated with poorer survival outcomes in 14 studies (52%). Twenty-seven studies showed that African American patients had worse outcomes across all included metrics including mortality, rates of surgical intervention, extent of resection, LOS, discharge disposition, and complication rates. Thirty studies showed that privately insured patients and patients with higher SES had better outcomes, including lower mortality, complication, and readmission rates. Six studies showed that worse outcomes were associated with treatment at safety-net and/or low-volume hospitals. The influence of Medicare or Medicaid status, or inequities affecting other minorities, was less clearly delineated. Ten studies (18%) were negative for evidence of disparities.

CONCLUSIONS

Significant disparities exist among patients with intracranial tumors, particularly affecting patients of African American race and lower SES. Efforts at the hospital, state, and national level must be undertaken to identify root causes of these issues.

Decompressive Craniectomy and Risk of Wound Infection After Microsurgical Treatment of Ruptured Aneurysms

BACKGROUND

Owing to prolonged hospitalization and the complexity of care required for patients with aneurysmal subarachnoid hemorrhage (aSAH), these patients have a high risk of complications. The risk for wound infection after microsurgical treatment for aSAH was analyzed.

METHODS

All patients who underwent microsurgical treatment for aSAH between August 1, 2007, and July 31, 2019, and were recorded in the Post-Barrow Ruptured Aneurysm Trial database were retrospectively reviewed. The patients were analyzed for risk factors for wound infection after treatment.

RESULTS

Of 594 patients who underwent microsurgical treatment for aSAH, 23 (3.9%) had wound infections. There was no significant difference in age between patients with wound infection and patients without infection (mean, 52.6 ± 12.2 years vs. 54.2 ± 4.0 years; P = 0.45). The presence of multiple comorbidities (including diabetes, tobacco use, and obesity), external ventricular drain, ventriculoperitoneal shunt, pneumonia, or urinary tract infection was not associated with an increased risk for wound infection. Furthermore, there was no significant difference in mean operative time between patients with wound infection and those without infection (280 ± 112 minutes vs. 260 ± 92 minutes; P = 0.38). Patients who required decompressive craniectomy (DC) were at increased risk of wound infection (odds ratio, 5.0; 95% confidence interval, 1.8-14.1; P = 0.002). Among the 23 total infections, 9 were diagnosed following cranioplasty after DC.

CONCLUSIONS

Microsurgical treatment for aSAH is associated with a relatively low risk of wound infection. However, patients undergoing DC may be at an increased risk for infection. Additional attention and comprehensive wound care are warranted for these patients.

Impact of Diabetes Mellitus on Adverse Outcomes After Meningioma Surgery

OBJECTIVE

We sought to investigate the association between diabetes mellitus and incidence of adverse outcomes in patients who underwent meningioma surgery.

METHODS

The 2012-2014 National Inpatient Sample database was used. Prolonged length of stay was indicated by values greater than the 90th percentile of the sample. The Fisher exact test and analysis of variance were used to compare demographics, hospital characteristics, comorbidity, and complications among race cohorts. Logistic regression was used to analyze the independent effect of diabetes on adverse outcomes.

RESULTS

After selecting for patients with primary diagnosis of meningioma who underwent a resection procedure, 7745 individuals were identified and divided into diabetic (n = 1518) and nondiabetic (n = 6227) cohorts. Demographics, hospital characteristics, and comorbidities were significantly different among the 2 cohorts. Average length of stay was longer in diabetic patients (8.15 vs. 6.04 days, P < 0.001), and total charges were higher in diabetic patients ($139,462.66 vs. $123,250.71, P < 0.001). Multivariate regression indicated diabetic patients have higher odds of experiencing a complication (odds ratio [OR] 1.442, 95% confidence interval [CI] 1.255-1.656, P < 0.001) and in-hospital mortality (OR 1.672, 95% CI 1.034-2.705, P = 0.036) after meningioma surgery. Analysis of individual postoperative complications revealed that diabetic patients experienced increased odds of pulmonary (OR 1.501, 95% CI 1.209-1.864, P < 0.001), neurologic (OR 1.690, 95% CI 1.383-2.065, P < 0.001), and urinary/renal complications (OR 2.618, 95% CI 1.933-3.545, P < 0.001). In addition, diabetic patients were more likely to have a prolonged length of stay (OR 1.694, 95% CI 1.389-2.065, P < 0.001).

CONCLUSIONS

Diabetes is an important factor associated with complications after meningioma surgery. Preventative measures must be taken to optimize postoperative outcomes in these patients.

Are preoperative chlorhexidine gluconate showers associated with a reduction in surgical site infection following craniotomy? A retrospective cohort analysis of 3126 surgical procedures

OBJECTIVE

Surgical site infection (SSI) is a complication linked to increased costs and length of hospital stay. Prevention of SSI is important to reduce its burden on individual patients and the healthcare system. The authors aimed to assess the efficacy of preoperative chlorhexidine gluconate (CHG) showers on SSI rates following cranial surgery.

METHODS

In November 2013, a preoperative CHG shower protocol was implemented at the authors' institution. A total of 3126 surgical procedures were analyzed, encompassing a time frame from April 2012 to April 2016. Cohorts before and after implementation of the CHG shower protocol were evaluated for differences in SSI rates.

RESULTS

The overall SSI rate was 0.6%. No significant differences (p = 0.11) were observed between the rate of SSI of the 892 patients in the preimplementation cohort (0.2%) and that of the 2234 patients in the postimplementation cohort (0.8%). Following multivariable analysis, implementation of preoperative CHG showers was not associated with decreased SSI (adjusted OR 2.96, 95% CI 0.67-13.1; p = 0.15).

CONCLUSIONS

This is the largest study, according to sample size, to examine the association between CHG showers and SSI following craniotomy. CHG showers did not significantly alter the risk of SSI after a cranial procedure.

Outcomes of infratentorial cranial surgery for tumor resection in older patients: An analysis of the National Surgical Quality Improvement Program

Background:

Poorer outcomes for infratentorial tumor resection have been reported. There is a lack of large multicenter analyses describing infratentorial surgery outcomes in older patients. We characterized outcomes in patients aged ≥65 years undergoing infratentorial cranial surgery.

Methods:

The National Surgical Quality Improvement Project database was queried from 2012 to 2018 for patients ≥18 years undergoing elective infratentorial cranial surgery for tumor resection. Patients were grouped into 65–74 years, ≥75 years, and 18–64 years cohorts. Multivariable regressions compared outcome measures.

Results:

Of 2212 patients, 28.3% were ≥65 years, of whom 24.8% were ≥75 years. Both older subpopulations had worse American Society of Anesthesiologists classification compared to controls (P < 0.01) and more comorbidities. Patients 65–74 and ≥75 years had higher rates of major complication (adjusted odds ratio [aOR] = 1.77, 95% CI = 1.13–2.79 and aOR = 3.44, 95% CI = 1.96–6.02, respectively), prolonged length of stay (LOS) (aOR = 1.89, 95% CI = 1.15–3.12 and aOR = 3.00, 95% CI = 1.65–5.44, respectively), and were more likely to be discharged to a location other than home (aOR = 2.43, 95% CI =1.73–3.4 and aOR = 3.41, 95% CI = 2.18–5.33, respectively) relative to controls. Patients ≥75 had higher rates of readmission (aOR = 1.86, 95% CI = 1.13–3.08) and mortality (aOR = 3.28, 95% CI = 1.21–8.89) at 30 days.

Conclusion:

Patients ≥65 years experienced more complications, prolonged LOS, and were less often discharged home than adults <65 years. Patients ≥75 years had higher rates of 30-day readmission and mortality. There is a need for careful preoperative optimization in older patients undergoing infratentorial tumor cranial surgery.

Recursive partitioning analysis of factors determining infection after intracranial tumor surgery

OBJECTIVES

Several factors are commonly associated with the occurrence of post-operative infection after craniotomy. However, the risk factors associated with tumor surgery have been less intensively investigated. The aim of the present study was to analyze the risk factors for infection and categorize patients according to risk rate.

METHODS

In this study, we retrospectively evaluated 987 adult patients consecutively submitted to craniotomy for tumor resection. The primary outcome was the occurrence of infection within 30 days after surgery. The following independent variables were assessed: age, gender, surgery duration, length of hospital stay prior to surgery, reoperation, body mass index, serum albumin, hemoglobin, lactic dehydrogenase, smoking, diabetes, corticoid use, preoperative chemotherapy, previous irradiation, elective or urgent indication for surgery, supra or infratentorial lesion location, and tumor histology. We performed a recursive partitioning analysis to assess the relative importance of these variables in predicting infection.

RESULTS

The model returned a 3-level classification: 1. CSF-leakage (relative contribution 70%), 2. Emergency surgery indication (18%), and 3. Tumor histology (8%). Additionally, partitioning clustered together 3 risk groups: 1. CSF-leakage group (probability of infection 72.5%), 2. No CSF-leakage and urgent surgery (mean probability 18.1%); and 3. no CSF-leakage and no urgent surgery (3.4%). The misclassification rate was 4.5%, the overall specificity and sensitivity were 99.6% and 75.5%, respectively, and the area under the ROC-curve was 0.6908.

CONCLUSION

Our analysis indicates that technical and treatment-related factors are significantly more relevant than patient- or disease-related factors in determining the risk of postoperative infection.

Systemic AAV6-synapsin-GFP administration results in lower liver biodistribution, compared to AAV1&2 and AAV9, with neuronal expression following ultrasound-mediated brain delivery

Non-surgical gene delivery to the brain can be achieved following intravenous injection of viral vectors coupled with transcranial MRI-guided focused ultrasound (MRIgFUS) to temporarily and locally permeabilize the blood-brain barrier. Vector and promoter selection can provide neuronal expression in the brain, while limiting biodistribution and expression in peripheral organs. To date, the biodistribution of adeno-associated viruses (AAVs) within peripheral organs had not been quantified following intravenous injection and MRIgFUS delivery to the brain. We evaluated the quantity of viral DNA from the serotypes AAV9, AAV6, and a mosaic AAV1&2, expressing green fluorescent protein (GFP) under the neuron-specific synapsin promoter (syn). AAVs were administered intravenously during MRIgFUS targeting to the striatum and hippocampus in mice. The syn promoter led to undetectable levels of GFP expression in peripheral organs. In the liver, the biodistribution of AAV9 and AAV1&2 was 12.9- and 4.4-fold higher, respectively, compared to AAV6. The percentage of GFP-positive neurons in the FUS-targeted areas of the brain was comparable for AAV6-syn-GFP and AAV1&2-syn-GFP. In summary, MRIgFUS-mediated gene delivery with AAV6-syn-GFP had lower off-target biodistribution in the liver compared to AAV9 and AAV1&2, while providing neuronal GFP expression in the striatum and hippocampus.

Readmission following extracranial-intracranial bypass surgery in the United States: nationwide rates, causes, risk factors, and volume-driven outcomes

OBJECTIVE

Extracranial-intracranial (EC-IC) bypass surgery remains an important treatment option for patients with moyamoya disease (MMD), intracranial arteriosclerotic disease (ICAD) with symptomatic stenosis despite the best medical management, and complex aneurysms. The therapeutic benefit of cerebral bypass surgery depends on optimal patient selection and the minimization of periprocedural complications. The nationwide burden of readmissions and associated complications following EC-IC bypass surgery has not been previously described. Therefore, the authors sought to analyze a nationwide database to describe the national rates, causes, risk factors, complications, and morbidity associated with readmission following EC-IC bypass surgery for MMD, ICAD, and aneurysms.

METHODS

The Nationwide Readmissions Database (NRD) was queried for the years 2010-2014 to identify patients who had undergone EC-IC bypass for MMD, medically failed symptomatic ICAD, or unruptured aneurysms. Predictor variables included demographics, preexisting comorbidities, indication for surgery, and hospital bypass case volume. A high-volume center (HVC) was defined as one that performed 10 or more cases/year. Outcome variables included perioperative stroke, discharge disposition, length of stay, total hospital costs, and readmission (30 days, 90 days). Multivariable analysis was used to identify predictors of readmission and to study the effect of treatment at HVCs on quality outcomes.

RESULTS

In total, 2500 patients with a mean age of 41 years were treated with EC-IC bypass surgery for MMD (63.1%), ICAD (24.5%), or unruptured aneurysms (12.4%). The 30- and 90-day readmission rates were 7.5% and 14.0%, respectively. Causes of readmission included new stroke (2.5%), wound complications (2.5%), graft failure (1.5%), and other infection (1.3%). In the multivariable analysis, risk factors for readmission included Medicaid/self-pay (OR 1.6, 95% CI 1.1-2.4, vs private insurance), comorbidity score (OR 1.2, 95% CI 1.1-1.4, per additional comorbidity), and treatment at a non-HVC (OR 1.9, 95% CI 1.1-3.0). Treatment at an HVC (17% of patients) was associated with significantly lower rates of nonroutine discharge dispositions (13.4% vs 26.7%, p = 0.004), ischemic stroke within 90 days (0.8% vs 2.9%, p = 0.03), 30-day readmission (3.9% vs 8.2%, p = 0.03), and 90-day readmission (8.6% vs 15.2%, p = 0.01). These findings were confirmed in a multivariable analysis. The authors estimate that centralization to HVCs may result in 333 fewer nonroutine discharges (50% reduction), 12,000 fewer hospital days (44% reduction), 165 fewer readmissions (43%), and a cost savings of $15.3 million (11% reduction).

CONCLUSIONS

Readmission rates for patients after EC-IC bypass are comparable with those after other common cranial procedures and are primarily driven by preexisting comorbidities, socioeconomic status, and treatment at low-volume centers. Periprocedural complications, including stroke, graft failure, and wound complications, occurred at the expected rates, consistent with those in prior clinical series. The centralization of care may significantly reduce perioperative complications, readmissions, and hospital resource utilization.

Predictors of readmission after craniotomy for meningioma resection: a nationwide readmission database analysis

BACKGROUND

Meningiomas are the most common benign primary brain tumors. The mainstay of treatment, surgical resection, is often curative. Given the excellent prognosis of these lesions, minimizing perioperative complications is of the utmost importance. With the establishment of the National Readmissions Database (NRD), researchers are now able to identify variables associated with postoperative complications beyond the index admission.

OBJECTIVE

In this study, we sought to identify the leading causes for non-elective readmission and variables associated with increased likelihood of readmission at 30 and 90 days after discharge following a craniotomy for meningioma resection.

METHODS

Adult inpatients who underwent craniotomy for meningioma resection between 2010 and 2014 were queried from the NRD. All-cause readmissions following craniotomy at 30 and 90 days were identified, and a multivariable logistic regression model was used to characterize independent risk factors.

RESULTS

Among 26,034 patients who received craniotomy for meningioma resection, 2825 (10.9%) were readmitted at 30 days and 3436 (16.1%) were readmitted at 90 days. Postoperative wound infection was the most common readmission diagnosis, occurring in 9.32% and 10.2% of 30- and 90-day readmissions respectively. Patient factors associated with increased likelihood of readmission included male gender, greater illness severity, non-routine discharge, index length of hospitalization, and having Medicare or Medicaid insurance.

CONCLUSIONS

Readmission following craniotomy for meningioma resection occurs at a clinically significant rate. Several patient factors were identified in association with all-cause 30- and 90-day readmissions. Further studies are required to identify means for preventing complications following discharge in these vulnerable patient populations.

A cross-sectional analysis of variables associated with morbidity and mortality in postoperative neurosurgical patients diagnosed with sepsis

BACKGROUND

Sepsis is a systemic, inflammatory response to infection associated with significant morbidity and mortality. There is a considerable lack of literature exploring sepsis in neurosurgery. We aimed to identify variables that were correlated with mortality and increased morbidity as defined by readmission and increased length of stay in postoperative neurosurgical patients that met a sepsis diagnosis.

METHODS

A retrospective chart review was conducted of 105 patients who underwent a neurosurgical operation at our institution from 2012 to 2017 who were discharged with at least one sepsis diagnosis code and who did not have a preoperative infection. We identified variables that were correlated with mortality, readmission, and increased length of stay.

RESULTS

Patients who survived were preferentially distributed towards lower ASA Physical Status Classification scores. A larger percentage of patients who did not survive had cranial surgery, whereas patients who survived were more likely to have undergone spinal surgery. Higher respiratory rates, higher maximum lactic acid levels, positive sputum cultures, and lower incoming Glasgow Coma Scores (GCS) were significantly correlated with mortality. A larger fraction of readmitted patients had positive surgical site cultures but had negative sputum cultures. Length of hospitalization was correlated with incoming GCS, non-elective operations, and Foley catheter, arterial line, central line, and endotracheal tube duration.

CONCLUSIONS

Neurosurgical postoperative patients diagnosed with sepsis may be risk stratified for mortality, readmission, and increased length of stay based on certain variables that may help direct their care. Further prospective studies are needed to explore causal relationships.

Establishment of a Nomogram for Predicting Lumbar Drainage-Related Meningitis: A Simple Tool to Estimate the Infection Risk

BACKGROUND

Lumbar drainage (LD) is one of the common treatment techniques in neurosurgery. There is a risk of secondary meningitis when using this modality. We aim to predict the probability of the complication by designing a nomogram.

METHODS

A retrospective study was conducted in a teaching hospital. Data were collected and LD-related meningitis (LDRM) was identified, mainly based on clinical manifestations and cerebrospinal fluid analysis. Univariate analysis was used to screen the risk factors, and binary logistic analysis was performed to build the prediction model, which was furtherly transferred into a nomogram. The prediction performance was evaluated by receiver operating characteristic (ROC) curve, Hosmer-Lemeshow test, and nomogram calibration plot. Internal validation was processed by using ordinary bootstrapping.

RESULTS

A total of 273 patients who match the research criteria were enrolled, in which 37 cases (13.6%) were confirmed to have LDRM. Univariate analysis showed the risk factors included diabetes (p = 0.003), admission on surgical intensive care unit (p = 0.012), duration time (p < 0.001), site leakage (p < 0.001), and craniotomy (p < 0.001). In multivariate analysis, four of the variables were identified as independent risk factors to establish a prediction model, and a graphical nomogram was designed. The area under the ROC curve was 0.837, and the p value in the Hosmer-Lemeshow test was 0.610, with a mean absolute error in the calibration plot calculated as 0.022. The indices in the testing set were in good accordance with the original set when internal validation was performed.

CONCLUSIONS

This is the first study to transform the prediction model of LDRM into a nomogram, which can be considered as a tool for clinicians to assess infection risk.

Strategy to enhance transgene expression in proximity of amyloid plaques in a mouse model of Alzheimer's disease

Gene therapy can be designed to efficiently counter pathological features characteristic of neurodegenerative disorders. Here, we took advantage of the glial fibrillary acidic protein (GFAP) promoter to preferentially enhance transgene expression near plaques composed of amyloid-beta peptides (Aβ), a hallmark of Alzheimer's disease (AD), in the TgCRND8 mouse model of amyloidosis.

Methods: The delivery of intravenously injected recombinant adeno-associated virus mosaic serotype 1/2 (rAAV1/2) to the cortex and hippocampus of TgCRND8 mice was facilitated using transcranial MRI-guided focused ultrasound in combination with microbubbles (MRIgFUS), which transiently and locally increases the permeability of the blood-brain barrier (BBB). rAAV1/2 expression of the reporter green fluorescent protein (GFP) under a GFAP promoter was compared to GFP expression driven by the constitutive human beta actin (HBA) promoter.

Results: MRIgFUS targeting the cortex and hippocampus facilitated the entry of rAAV1/2 and GFP expression under the GFAP promoter was localized to GFAP-positive astrocytes. Adjacent to Aβ plaques where GFAP is upregulated, the volume, surface area, and fluorescence intensity of the transgene GFP were greater in rAAV1/2-GFAP-GFP compared to rAAV1/2-HBA-GFP treated animals. In peripheral organs, GFP expression was particularly strong in the liver, irrespective of the promoter.

Conclusion: The GFAP promoter enhanced transgene expression in proximity of Aβ plaques in the brain of TgCRND8 mice, and it also resulted in significant expression in the liver. Future gene therapies for neurological disorders could benefit from using a GFAP promoter to regulate transgene expression in response to disease-induced astrocytic reactivity.

Pre-operative smoking history increases risk of infection in deep brain stimulation surgery

Although general risk of deep brain stimulation (DBS) therapy has been previously described, application of risk prediction at the individual patient level is still largely at the discretion of a treating physician or a multidisciplinary team. To explore associations between potentially modifiable patient characteristics and common adverse events following DBS surgery, we retrospectively reviewed consecutive adult patients who had undergone new DBS electrode placement surgeries at two high-volume tertiary referral centers between October 1997 and May 2018. Among 501 patients included in the analysis (mean age (SD), 64.6 (10.4) years), 165 (32.9%) were female, 67 (13.4%) had diabetes, 231 (46.1%) had hypertension, 25 (5.0%) were smokers, 27 (5.4%) developed an infection, 15 (3.0%) had intracranial or intraventricular hemorrhage, and 53 (10.6%) had an unplanned return to the operating room. Patients who developed a surgical site infection were more likely to report history of smoking before DBS surgery (16% vs 5%, p = 0.04). There was a trend for patients with hypertension to be at risk for intracranial hemorrhage (p = 0.11). In conclusion, this multicenter study demonstrated an association between preoperative smoking and increased risk of infection following new DBS implantation surgery. Counseling about this risk should be considered in preoperative evaluation of patients who are considering undergoing a DBS procedure.