Four Streams Within the Prefrontal Cortex: Integrating Structural and Functional Connectivity.

Merging functional evidence derived from studies of autism spectrum disorder and attention-deficit/hyperactivity disorder converges in four neural streams of the prefrontal cortex, hence suggesting a model of information processing through four streams: motor through Brodmann area (BA) 8, emotion through BA 9, memory through BA 10, and emotional-related sensory through BA 11. A growing body of functional data has been supporting this model of information processing. Nevertheless, the underlying structural connectivity was only recently unveiled by a population-based high-definition tractography study with data from 1,065 individuals. This update provides a brief overview of recent evidence supporting the anatomofunctional integration of the four streams of the prefrontal cortex and reviews the white matter fiber tracts subserving the four streams.

The lateral retrocanthal transorbital endoscopic approach to the middle fossa: cadaveric stepwise approach and review of quantitative cadaveric data.

OBJECTIVE: The lateral retrocanthal transorbital endoscopic approach (LRCTEA) facilitates trajectory to the middle fossa, preserving the lateral canthal tendon and thus avoiding postoperative complications such as eyelid malposition. Here, the authors sought to define the surgical anatomy and technique of LRCTEA using a stepwise approach in cadaveric heads and offer an in-depth examination of existing quantitative data from cadaveric studies. METHODS: The authors performed LRCTEA to the middle cranial fossa under neuronavigation in 7 cadaveric head specimens that underwent high-resolution (1-mm) CT scans preceding the dissections. RESULTS: The LRCTEA provided access to middle fossa regions including the cavernous sinus, Meckel's cave, and medial temporal lobe. The trajectories and endpoints of the approach were confirmed using electromagnetic neuronavigation. A stepwise approach was delineated and recorded. CONCLUSIONS: The authors' cadaveric study delineates the surgical anatomy and technique of the LRCTEA, providing a stepwise approach for its implementation. As these approaches continue to evolve, their development and refinement will play an important role in expanding the surgical options available to neurosurgeons, ultimately improving outcomes for patients with complex skull base pathologies. The LRCTEA presents a promising advancement in skull base surgery, particularly for accessing challenging middle fossa regions. However, surgeons must remain vigilant to potential complications, including transient diplopia, orbital hematoma, or damage to the optic apparatus.

Parcellating the vertical associative fiber network of the temporoparietal area: Evidence from focused anatomic fiber dissections.

Introduction: The connectivity of the temporoparietal (TP) region has been the subject of multiple anatomical and functional studies. Its role in high cognitive functions has been primarily correlated with long association fiber connections. As a major sensory integration hub, coactivation of areas within the TP requires a stream of short association fibers running between its subregions. The latter have been the subject of a small number of recent in vivo and cadaveric studies. This has resulted in limited understanding of this network and, in certain occasions, terminology ambiguity. Research question: To systematically study the vertical parietal and temporoparietal short association fibers. Material and methods: Thirteen normal, adult cadaveric hemispheres, were treated with the Klinger's freeze-thaw process and their subcortical anatomy was studied using the microdissection technique. Results: Two separate fiber layers were identified. Superficially, directly beneath the cortical u-fibers, the Stratum proprium intraparietalis (SP) was seen connecting Superior Parietal lobule and Precuneal cortical areas to inferior cortical regions of the Parietal lobe, running deep to the Intraparietal sulcus. At the same dissection level, the IPL-TP fibers were identified as a bundle connecting the Inferior Parietal lobule with posterior Temporal cortical areas. At a deeper level, parallel to the Arcuate fasciculus fibers, the SPL-TP fibers were seen connecting the Superior Parietal lobule to posterior Temporal cortical areas. Discussion and conclusion: To our knowledge this is the first cadaveric dissection study to comprehensively study and describe of the vertical association fibers of the temporoparietal region while proposing a universal terminology.

Frailty as a predictor of postoperative outcomes in neurosurgery: a systematic review.

INTRODUCTION: Baseline frailty status has been utilized to predict a wide range of outcomes and guide preoperative decision making in neurosurgery. This systematic review aims to analyze existing literature on the utilization of frailty as a predictor of neurosurgical outcomes. EVIDENCE ACQUISITION: We conducted a systematic review following PRISMA guidelines. Studies that utilized baseline frailty status to predict outcomes after a neurosurgical intervention were included in this systematic review. Studies that utilized sarcopenia as the sole measure of frailty were excluded. PubMed, EMBASE, and Cochrane library was searched from inception to March 1st, 2023, to identify relevant articles. EVIDENCE SYNTHESIS: Overall, 244 studies met the inclusion criteria. The 11-factor modified frailty index (mFI-11) was the most utilized frailty measure (N.=91, 37.2%) followed by the five-factor modified Frailty Index (mFI-5) (N.=80, 32.7%). Spine surgery was the most common subspecialty (N.=131, 53.7%), followed by intracranial tumor resection (N.=57, 23.3%), and post-operative complications were the most reported outcome (N.=130, 53.2%) in neurosurgical frailty studies. The USA and the Bowers author group published the greatest number of articles within the study period (N.=176, 72.1% and N.=37, 15.2%, respectively). CONCLUSIONS: Frailty literature has grown exponentially over the years and has been incorporated into neurosurgical decision making. Although a wide range of frailty indices exist, their utility may vary according to their ability to be incorporated in the outpatient clinical setting.

Clinical Characteristics and Surgical Outcomes of 2542 Patients with Spinal Schwannomas: A Systematic Review and Meta-Analysis.

OBJECTIVE: This study was conducted to systematically analyze the data on the clinical features, surgical treatment, and outcomes of spinal schwannomas. METHODS: We conducted a systematic review and meta-analysis under the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A search of bibliographic databases from January 1, 2001, to May 31, 2021, yielded 4489 studies. Twenty-six articles were included in our final qualitative systematic review and quantitative meta-analysis. RESULTS: Analysis of 2542 adult patients' data from 26 included studies showed that 53.5% were male, and the mean age ranged from 35.8 to 57.1 years. The most common tumor location was the cervical spine (34.2%), followed by the thoracic spine (26.2%) and the lumbar spine (18.5%). Symptom severity was the most common indicator for surgical treatment, with the most common symptoms being segmental back pain, sensory/motor deficits, and urinary dysfunction. Among all patients analyzed, 93.8% were treated with gross total resection, which was associated with better prognosis and less chance of recurrence than subtotal resection. The posterior approach was the most common (87.4% of patients). The average operative time was 4.53 hours (95% confidence interval [CI], 3.18-6.48); the average intraoperative blood loss was 451.88 mL (95% CI, 169.60-1203.95). The pooled follow-up duration was 40.6 months (95% CI, 31.04-53.07). The schwannoma recurrence rate was 5.3%. Complications were particularly low and included cerebrospinal fluid leakage, wound infection, and the sensory-motor deficits. Most of the patients experienced complete recovery or significant improvement of preoperative neurological deficits and pain symptoms. CONCLUSIONS: Our analysis suggests that segmental back pain, sensory/motor deficits, and urinary dysfunction are the most common symptoms of spinal schwannomas. Surgical resection is the treatment of choice with overall good reported outcomes and particularly low complication rates. gross total resection offers the best prognosis with the slightest chance of tumor recurrence and minimal risk of complications.

The frailty-driven predictive model for failure to rescue among patients who experienced a major complication following cervical decompression and fusion: an ACS-NSQIP analysis of 3,632 cases (2011-2020).

BACKGROUND CONTEXT: Preoperative risk stratification for patients considering cervical decompression and fusion (CDF) relies on established independent risk factors to predict the probability of complications and outcomes in order to help guide pre and perioperative decision-making. PURPOSE: This study aims to determine frailty's impact on failure to rescue (FTR), or when a mortality occurs within 30 days following a major complication. STUDY DESIGN/SETTING: Cross-sectional retrospective analysis of retrospective and nationally-representative data. PATIENT SAMPLE: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for all CDF cases from 2011-2020. OUTCOME MEASURES: CDF patients who experienced a major complication were identified and FTR was calculated as death or hospice disposition within 30 days of a major complication. METHODS: Frailty was measured by the Risk Analysis Index-Revised (RAI-Rev). Baseline patient demographics and characteristics were compared for all FTR patients. Significant factors were assessed by univariate and multivariable regression for the development of a frailty-driven predictive model for FTR. The discriminative ability of the predictive model was assessed using a receiving operating characteristic (ROC) curve analysis. RESULTS: There were 3632 CDF patients who suffered a major complication and 7.6% (277 patients) subsequently expired or dispositioned to hospice, the definition of FTR. Independent predictors of FTR were nonelective surgery, frailty, preoperative intubation, thrombosis or embolic complication, unplanned intubation, on ventilator for >48 hours, cardiac arrest, and septic shock. Frailty, and a combination of preoperative and postoperative risk factors in a predictive model for FTR, achieved outstanding discriminatory accuracy (C-statistic = 0.901, CI: 0.883-0.919). CONCLUSION: Preoperative and postoperative risk factors, combined with frailty, yield a highly accurate predictive model for FTR in CDF patients. Our model may guide surgical management and/or prognostication regarding the likelihood of FTR after a major complication postoperatively with CDF patients. Future studies may determine the predictive ability of this model in other neurosurgical patient populations.

Anxiety and Depression in Pediatric-Onset Traumatic Spinal Cord Injury: A Systematic Review.

BACKGROUND: Traumatic spinal cord injury (TSCI) is a debilitating neurological condition with significant long-term consequences on the mental health and well-being of affected individuals. We aimed to investigate anxiety and depression in individuals with pediatric-onset TSCI. METHODS: PubMed, Scopus, and Web of Science databases were searched from inception to December 20th, 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, and studies were included according to the eligibility criteria. RESULTS: A total of 1013 articles were screened, and 18 studies with 4234 individuals were included in the final review. Of these, 1613 individuals (38.1%) had paraplegia, whereas 1658 (39.2%) had tetraplegia. A total of 1831 participants (43.2%) had complete TSCI, whereas 1024 (24.2%) had incomplete TSCI. The most common etiology of TSCI with 1545 people (36.5%) was motor vehicle accidents. The youngest mean age at the time of injury was 5.92 ± 4.92 years, whereas the oldest was 14.6 ± 2.8 years. Patient Health Questionnaire-9 was the most common psychological assessment used in 9 studies (50.0%). Various risk factors, including pain in 4 studies (22.2%), reduced sleep quality, reduced functional independence, illicit drug use, incomplete injury, hospitalization, reduced quality of life, and duration of injury in 2 (11.1%) studies, each, were associated with elevated anxiety and depression. CONCLUSIONS: Different biopsychosocial risk factors contribute to elevated rates of anxiety and depression among individuals with pediatric-onset TSCI. Individuals at risk of developing anxiety and depression should be identified, and targeted support should be provided. Future large-scale studies with long-term follow-up are required to validate and extend these findings.

Vacuum-assisted scalp repositioning: a novel temporizing approach to acute sinking skin flap syndrome. Illustrative cases.

BACKGROUND: This report describes the use of a novel approach to address acute sinking skin flap syndrome (SSFS), a postcraniectomy complication arising from brain dysfunction beneath the skull defect. The authors present a case series of two patients, emphasizing the prospective application of an external plaster cast in tandem with a vacuum-assisted closure (VAC) device (wound VAC) to promptly reposition the scalp and relieve brain compression. OBSERVATIONS: Following intervention, one patient showed immediate neurological improvement, with complete resolution of symptoms within hours. Conversely, the second patient developed nonconvulsive status epilepticus. Computed tomography scans postintervention validated the successful scalp repositioning and mass effect resolution in both instances. This temporary approach proved successful in one patient with moderate symptoms, serving as a bridge to cranioplasty. LESSONS: The integration of an external plaster cast and wound VAC offers a cost-effective and prompt solution for patients with acute SSFS pending cranioplasty. Appropriate patient selection and heightened caution for those with severe symptoms should be exercised.

The anatomy of the four streams of the prefrontal cortex. Preliminary evidence from a population based high definition tractography study.

The model of the four streams of the prefrontal cortex proposes 4 streams of information: motor through Brodmann area (BA) 8, emotion through BA 9, memory through BA 10, and emotional-related sensory through BA 11. Although there is a surge of functional data supporting these 4 streams within the PFC, the structural connectivity underlying these neural networks has not been fully clarified. Here we perform population-based high-definition tractography using an averaged template generated from data of 1,065 human healthy subjects acquired from the Human Connectome Project to further elucidate the structural organization of these regions. We report the structural connectivity of BA 8 with BA 6, BA 9 with the insula, BA 10 with the hippocampus, BA 11 with the temporal pole, and BA 11 with the amygdala. The 4 streams of the prefrontal cortex are subserved by a structural neural network encompassing fibers of the anterior part of the superior longitudinal fasciculus-I and II, corona radiata, cingulum, frontal aslant tract, and uncinate fasciculus. The identified neural network of the four streams of the PFC will allow the comprehensive analysis of these networks in normal and pathological brain function.

Awake craniotomy during pregnancy: A systematic review of the published literature.

Neurosurgical pathologies in pregnancy pose significant complications for the patient and fetus, and physiological stressors during anesthesia and surgery may lead to maternal and fetal complications. Awake craniotomy (AC) can preserve neurological functions while reducing exposure to anesthetic medications. We reviewed the literature investigating AC during pregnancy. PubMed, Scopus, and Web of Science databases were searched from the inception to February 7th, 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Studies in English investigating AC in pregnant patients were included in the final analysis. Nine studies composed of nine pregnant patients and ten fetuses (one twin-gestating patient) were included. Glioma was the most common pathology reported in six (66.7%) patients. The frontal lobe was the most involved region (4 cases, 44.4%), followed by the frontoparietal region (2 cases, 22.2%). The awake-awake-awake approach was the most common protocol in seven (77.8%) studies. The shortest operation time was two hours, whereas the longest one was eight hours and 29 min. The mean gestational age at diagnosis was 13.6 ± 6.5 (2-22) and 19.6 ± 6.9 (9-30) weeks at craniotomy. Seven (77.8%) studies employed intraoperative fetal heart rate monitoring. None of the AC procedures was converted to general anesthesia. Ten healthy babies were delivered from patients who underwent AC. In experienced hands, AC for resection of cranial lesions of eloquent areas in pregnant patients is safe and feasible and does not alter the pregnancy outcome.

Gender concordance and publication productivity within Neurosurgical Focus: a 10-year review (2013-2022).

OBJECTIVE: The "leaky academic pipeline" describes how female representation in leadership positions has remained stagnant despite an increase in the number of female trainees. Female mentorship to female mentees, and female role models at higher academic positions have been shown to positively influence academic productivity. To the authors' knowledge, the impact of female editorial board representation on authorship trends in neurosurgical journals remains undescribed. This study aimed to analyze trends in the representation of female topic editors and its impact on female authorship within Neurosurgical Focus over a 10-year period. METHODS: Publicly available data were collected from the journal's website, inclusive from January 2013 to December 2022. The articles were grouped into technical and nontechnical themes based on their relevance to specific technical details regarding surgical techniques. Female gender-concordant publications were defined as publications having a female first author (or co-first author) and a female senior author. Linear regression analysis determined trends in publishing. Odds ratios and 95% CIs were calculated using logistic regression analysis. Pearson correlation and cross-correlation analyses were used to examine each pairwise comparison of time series. The statistical significance of associations was evaluated using t-tests and chi-square and Fisher's exact tests. RESULTS: The number of female topic editors and gender-concordant authors increased over time (p < 0.05). Women accounted for ≥ 50% of the topic editors on nontechnical themes relevant to education and gender diversity. Having a female senior author was associated with higher publication productivity for original research and review articles among female authors (OR 13.73, 95% CI 1.75-394.31; p < 0.05). Female authors had higher odds of publishing editorials with a female topic editor (OR 3.81, 95% CI 1.37-11.02; p < 0.01). Publications with female first and senior authors were significantly more likely to have female topic editors (OR 4.05, 95% CI 1.38-12.92; p < 0.01). A positive association was observed between female senior authors and female topic editors at lag -8, with a correlation coefficient of 0.19 (p = 0.03). CONCLUSIONS: Female attending-to-female trainee mentorship and female representation among editorial boards play a crucial role in enhancing academic productivity among women. Efforts to sustain academic productivity during the early-career period would presumably help increase female representation in neurosurgery.

Frailty indices in patients undergoing surgical resection of brain metastases: a systematic review.

Brain metastases are a relatively common occurrence in patients with primary malignancies, with an incidence ranging from 9 to 17%. Their prevalence has increased due to treatment advancements that have led to improved survival in cancer patients. Frailty has demonstrated the ability to outperform greater patient age in surgical decision-making by predicting postoperative adverse events that include mortality, extended length of hospital stay, non-routine discharge disposition, and postoperative complications. Although predictive models based on frailty have been increasingly utilized in literature, their generalizability remains questionable due to inadequacies in model development and validation. Our systematic review describes development and validation cohorts of frailty indices used in patients undergoing surgical resection of brain metastases and serves as a guide to their incorporation in the outpatient clinical setting. A systematic review of literature was performed using PubMed and Google Scholar. Articles that reported outcomes using frailty indices in patients undergoing surgical resection of brain metastases were included. The Newcastle Ottawa Scale (NOS) was used to assess for risk of bias across individual studies. Studies with NOS > 5 were considered high quality. We identified 238 articles through our search strategy. After a title and abstract screen, followed by a full text review, 9 articles met criteria for inclusion. The 5- and 11-factor modified frailty indices were most frequently utilized (n = 4). Five studies utilized single-hospital databases, and four utilized nationwide databases. Six studies were considered high-quality based on the NOS. Although frailty indices have demonstrated the ability to predict outcomes in patients undergoing surgical resection of brain metastases, further validation of these indices is necessary prior to their incorporation in clinical practice.

An Applied Anatomic Guide to Anterior Temporal Lobectomy and Amygdalohippocampectomy: Laboratory Cranial and White Matter Dissections to Inform Surgical Practice.

BACKGROUND AND OBJECTIVES: Anterior temporal lobectomy and amygdalohippocampectomy is a challenging procedure because of the deep surgical trajectory and complex regional neurovascular anatomy. A thorough knowledge of the involved anatomic structures is crucial for a safe and effective procedure. Our objective is to explore the white matter pathways in or around the operative corridor and to illuminate the 3-dimensional relationships of the pertinent operative parenchymal and skull base anatomy, aiming to inform and simplify surgical practice. METHODS: Four normal, adult, cadaveric, formalin-fixed cerebral hemispheres (2 left and 2 right) treated with the Klinger's technique and 2 formalin-fixed and colored-latex-injected cadaveric heads (4 sides) were used. Focused white matter and cadaveric dissections were used to study the relevant anatomy implicated during an anterior temporal lobectomy. Four illustrative cases were also included. Digital photographs from every dissection step were obtained. RESULTS: Major white matter pathways that are inevitably traversed during the approach are the inferior longitudinal fasciculus, uncinate fasciculus, and inferior arm of the cingulum. Tracts that can be potentially injured, should the dissection plane tilt inadvertently superiorly or posteriorly, are the inferior fronto-occipital fasciculus, Meyer's loop, superior longitudinal fasciculus/arcuate fasciculus complex, and basal ganglia. Consistent cranial and parenchymal landmarks that can act as a roadmap during the procedure are recorded and paired with their intraoperative equivalent to provide a thorough, yet simple, stepwise guide for the surgeon. CONCLUSION: White matter dissections, cadaveric cranial dissections, and intraoperative images are put together to provide a simplified stepwise surgical manual for anterior temporal lobectomy. Laboratory investigations that focus on the intricate 3-dimensional relationships of the pertinent operative anatomy from the surgeon's eye may enrich anatomic knowledge and push surgical boundaries, to minimize complication rates and ultimately improve patient outcomes.

Failure to rescue as a patient safety indicator for neurosurgical patients: are we there yet? A systematic review.

Failure to rescue (FTR) is a standardized patient safety indicator (PSI-04) developed by the Agency for Healthcare Research and Quality (AHRQ) to assess the ability of a healthcare team to prevent mortality following a major complication. However, FTR rates vary and are impacted by non-modifiable individual patient characteristics such as baseline frailty. This raises concerns regarding the validity of FTR as an objective quality metric, as not all patients have the same baseline frailty level, or physiological reserve, to recover from major complications. Literature from other surgical specialties has identified flaws in FTR and called for risk-adjusted metrics. Currently, knowledge of factors influencing FTR and its subsequent implementation in neurosurgical patients are limited. The present review assesses trends in FTR utilization to assess how FTR performs as an objective neurosurgery quality metric. This review then proposes how FTR may be best modified to optimize use in neurosurgical patients. A PubMed search was performed to identify articles published until August 9, 2023. Studies that reported FTR as an outcome in patients undergoing neurosurgical procedures were included. A qualitative assessment was performed using the Newcastle Ottawa Scale (NOS). The initial search revealed 1232 citations. After a title and abstract screen, followed by a full text screen, 12 studies met criteria for inclusion. These articles measured FTR across a total of 764,349 patients undergoing neurosurgical procedures. Five studies analyzed FTR with regard to hospital characteristics, and three studies utilized patient characteristics to predict FTR. All studies were considered high quality based on the NOS. Modifications in criteria to measure FTR are necessary since FTR depends on patient characteristics like frailty. This would allow for the incorporation of risk-adjusted FTR metrics that would aid in clinical decision making in neurosurgical patients.

Preoperative frailty and 30-day mortality after resection of brain metastases: a multicenter surgical registry analysis of 11,038 patients.

OBJECTIVE: Surgery plays a key role in the management of brain metastases. Stratifying surgical risk and individualizing treatment will help optimize outcomes because there is clinical equipoise between radiation and resection as treatment options for many patients. Here, the authors used a multicenter database to assess the prognostic utility of baseline frailty, calculated with the Risk Analysis Index (RAI), for prediction of mortality within 30 days after surgery for brain metastasis. METHODS: The authors pooled patients who had been surgically treated for brain metastasis from the American College of Surgeons National Surgical Quality Improvement Program database (2012-2020). The authors studied the relationship between preoperative calculated RAI score and 30-day mortality after surgery for brain metastasis by using linear-by-linear proportional trend tests and binary logistic regression. The authors calculated C-statistics (with 95% CIs) in receiver operating characteristic (ROC) curve analysis to assess discriminative accuracy. RESULTS: The authors identified 11,038 patients who underwent brain metastasis resection with a median (interquartile range) age of 62 (54-69) years. The authors categorized patients into four groups on the basis of RAI: robust (RAI 0-20), 8.1% of patients; normal (RAI 21-30), 9.2%; frail (RAI 31-40), 75%; and severely frail (RAI ≥ 41), 8.1%. The authors found a positive correlation between 30-day mortality and frailty. RAI demonstrated superior predictive discrimination for 30-day mortality as compared with the 5-factor modified frailty index (mFI-5) on ROC analysis (C-statistic 0.65, 95% CI 0.65-0.66). CONCLUSIONS: The RAI frailty score accurately estimates 30-day mortality after brain metastasis resection and can be calculated online with an open-access software tool: https://nsgyfrailtyoutcomeslab.shinyapps.io/BrainMetsResection/. Accordingly, RAI can be utilized to measure surgical risk, guide treatment options, and optimize outcomes for patients with brain metastases. RAI has superior discrimination for predicting 30-day mortality compared with mFI-5.

Causes and Predictors of Unplanned Readmission in Patients Undergoing Intracranial Tumor Resection: A Multicenter Analysis of 31,776 Patients.

BACKGROUND: Although unplanned readmission is a postoperative outcome metric associated with significant morbidity and financial burden, precise assessment tools for its prediction have not yet been developed. The Risk Analysis Index (RAI) could potentially be used to help improve the prediction of unplanned readmissions for patients undergoing intracranial tumor resection (ITR). In the present study, we evaluate the predictive accuracy of frailty on 30-day unplanned readmission after ITR using the RAI. METHODS: Data were obtained from the American College of Surgeons National Surgical Quality Improvement Program database. The baseline characteristics, preoperative clinical status, and outcomes were compared between patients with and without unplanned readmission. Frailty was calculated using the RAI. Univariate and multivariate logistic regression analyses were performed to identify independent associations between unplanned readmissions and patient characteristics. RESULTS: The unplanned readmission rate for this cohort (n = 31,776) was 10.8% (n = 3420). Of the 3420 readmitted patients, 958 required unplanned reoperation. Multiple characteristics were significantly different between the 2 groups, including age, body mass index, comorbidities, and RAI groups (P < 0.05). The common causes of unplanned readmission included infection (9.4%), seizures (6%), and pulmonary embolism (4%). The patient characteristics identified as reliable predictors of unplanned readmission included age, body mass index, functional status, diabetes, hypertension, hyponatremia, and the patient's RAI score (P < 0.05). Frail status, hyponatremia, leukocytosis, hypertension, and thrombocytosis were significant predictors of unplanned readmissions. CONCLUSIONS: The RAI is a reliable preoperative frailty index for predicting unplanned readmissions after ITR. Using the RAI could decrease unplanned readmissions by identifying high-risk patients and enabling future implementation of appropriate management guidelines.

Baseline Frailty and Discharge to Advanced Care Facilities in Patients Undergoing Lumbar Interbody Fusion for Lumbar Degenerative Disease: A Multicenter Registry Analysis of 7153 Patient Cases Comparing the Risk Analysis Index to the 5-Factor Modified Frailty Index.

OBJECTIVE: To evaluate the impact of frailty, as measured by the 5-factor modified Frailty Index (mFI-5) and the Risk Analysis Index (RAI), on advanced care facility discharge (FD) in patients who underwent lumbar fusion for lumbar degenerative spine disease. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (2012-2020) was queried for adults (≥18 years) undergoing lumbar fusion for lumbar degenerative disease. Descriptive statistics and univariate crosstabulation were used to assess baseline demographics, preoperative comorbidities, and postoperative outcomes. Receiver operating characteristic curve analysis was used to assess the discriminative threshold of the mFI-5 and RAI on FD within this population. RESULTS: The median patient age in this study cohort (N = 7153) was 56 years and FD occurred in 7.3% of cases. Receiver operating characteristic curve analysis demonstrated that both the mFI-5 and the RAI accurately predicted FD (C-statistics: mFI-5: 0.627; RAI: 0.746). DeLong's test found that the RAI had superior discrimination when compared to the mFI-5 (P < 0.0001). CONCLUSIONS: RAI is a reliable predictor of FD in lumbar degenerative disease patients who underwent lumbar interbody fusion and demonstrated superior discrimination compared to the mFI-5. Identification of patients at risk for FD may facilitate more precise risk stratification to enable better preoperative decision-making and help set more realistic expectations of care.

Frailty predicts hospital acquired infections after brain tumor resection: Analysis of 27,947 patients' data from a prospective multicenter surgical registry.

BACKGROUND: Hospital acquired infections (HAIs) present a significant source of economic burden in the United States. The role of frailty as a predictor of HAIs has not been illustrated among patients undergoing craniotomy for brain tumor resection (BTR). METHODS: The American College of Surgery National Surgical Quality Improvement Program (ACS-NSQIP) database was queried from 2015 to 2019 to identify patients who underwent craniotomy for BTR. Patients were categorized as pre-frail, frail and severely frail using the 5-factor Modified Frailty Index (mFI-5). Demographics, clinical and laboratory parameters, and HAIs were assessed. A multivariate logistic regression model was created to predict the occurrence of HAIs using these variables. RESULTS: A total of 27,947 patients were assessed. 1772 (6.3 %) of these patients developed an HAI after surgery. Severely frail patients were more likely to develop an HAI in comparison to pre-frail patients (OR = 2.48, 95 % CI = 1.65-3.74, p < 0.001 vs. OR = 1.43, 95 % CI = 1.18-1.72, p < 0.001). Ventilator dependence was the strongest predictor of developing an HAI (OR = 2.96, 95 % CI = 1.86-4.71, p < 0.001). CONCLUSION: Baseline frailty, by virtue of its ability to predict HAIs, should be utilized in adopting measures to reduce the incidence of HAIs.

A Predictive Model of Failure to Rescue After Thoracolumbar Fusion.

OBJECTIVE: Although failure to rescue (FTR) has been utilized as a quality-improvement metric in several surgical specialties, its current utilization in spine surgery is limited. Our study aims to identify the patient characteristics that are independent predictors of FTR among thoracolumbar fusion (TLF) patients. METHODS: Patients who underwent TLF were identified using relevant diagnostic and procedural codes from the National Surgical Quality Improvement Program (NSQIP) database from 2011-2020. Frailty was assessed using the risk analysis index (RAI). FTR was defined as death, within 30 days, following a major complication. Univariate and multivariable analyses were used to compare baseline characteristics and early postoperative sequelae across FTR and non-FTR cohorts. Receiver operating characteristic (ROC) curve analysis was used to assess the discriminatory accuracy of the frailty-driven predictive model for FTR. RESULTS: The study cohort (N = 15,749) had a median age of 66 years (interquartile range, 15 years). Increasing frailty, as measured by the RAI, was associated with an increased likelihood of FTR: odds ratio (95% confidence interval [CI]) is RAI 21-25, 1.3 [0.8-2.2]; RAI 26-30, 4.0 [2.4-6.6]; RAI 31-35, 7.0 [3.8-12.7]; RAI 36-40, 10.0 [4.9-20.2]; RAI 41- 45, 21.5 [9.1-50.6]; RAI ≥ 46, 45.8 [14.8-141.5]. The frailty-driven predictive model for FTR demonstrated outstanding discriminatory accuracy (C-statistic = 0.92; CI, 0.89-0.95). CONCLUSION: Baseline frailty, as stratified by type of postoperative complication, predicts FTR with outstanding discriminatory accuracy in TLF patients. This frailty-driven model may inform patients and clinicians of FTR risk following TLF and help guide postoperative care after a major complication.