Incidence of acute kidney injury after noncardiac surgery in patients receiving intraoperative dexmedetomidine: a retrospective study.

Background: Postoperative acute kidney injury (AKI) is a common complication and is associated with increased hospital length of stay and 30 day all-cause mortality. Unfortunately, we have neither a defined strategy to prevent AKI nor an effective treatment. In vitro, animal, and human studies have suggested that dexmedetomidine may have a renoprotective effect. We conducted a retrospective cohort study to evaluate if intraoperative dexmedetomidine was associated with a reduced incidence of AKI. Methods: We collected data from 6625 patients who underwent major non-cardiothoracic cancer surgery. Before and after propensity score matching, we compared the incidence of postoperative AKI in patients who received intraoperative dexmedetomidine and those who did not. AKI was defined according to the Kidney Disease Improving Global Outcomes (creatinine alone values) criteria and calculated for postoperative Days 1, 2, and 3. Results: Twenty per cent (n=1301) of the patients received dexmedetomidine. The mean [standard deviation] administered dose was 78 [49.4] mcg. Patients treated with dexmedetomidine were matched to those who did not receive the drug. Patients receiving dexmedetomidine had a longer anaesthesia duration than the non-dexmedetomidine group. The incidence of AKI was not significantly different between the groups (dexmedetomidine 8% vs no dexmedetomidine 7%; P=0.333). The 30 day rates of infection, cardiovascular complications, or reoperation attributable to bleeding were higher in patients treated with dexmedetomidine. The 30 day mortality rate was not statistically different between the groups. Conclusions: The administration of dexmedetomidine during major non-cardiothoracic cancer surgery is not associated with a reduction in AKI within 72 h after surgery.

Long-latency gamma modulation after median nerve stimulation delineates the central sulcus and contrasts the states of consciousness.

OBJECTIVE: To evaluate the functional use of sub-band modulations in somatosensory evoked potentials (SSEPs) to discriminate between the primary somatosensory (S1) and motor (M1) areas and contrast the states of consciousness. METHODS: During routine intraoperative cortical mapping, SSEPs were recorded with electrocorticography (ECoG) grids from the sensorimotor cortex of eight patients in the anesthetized and awake states. We conducted a time-frequency analysis on the SSEP trace to extract the spectral modulations in each state and visualize their spatial topography. RESULTS: We observed late gamma modulation (60-250 Hz) in all subjects approximately 50 ms after stimulation onset, extending up to 250 ms in each state. The late gamma activity enhancement was predominant in S1 in the awake state, where it discriminated S1 from M1 at a higher accuracy (92 %) than in the anesthetized state (accuracy = 70 %). CONCLUSIONS: These results showed that sensorimotor mapping does not need to rely on only SSEP phase reversal. The long latency gamma modulation can serve as a biomarker for primary sensorimotor localization and monitor the level of consciousness in neurosurgical practice. SIGNIFICANCE: While the intraoperative assessment of SSEP phase reversal with ECoG is widely employed to delineate the central sulcus, the median nerve stimulation-induced spatio-spectral patterns can distinctly localize it and distinguish between conscious states.

Development and implementation of an institutional enhanced recovery program data process.

Background: With increasing implementation of enhanced recovery programs (ERPs) in clinical practice, standardised data collection and reporting have become critical in addressing the heterogeneity of metrics used for reporting outcomes. Opportunities exist to leverage electronic health record (EHR) systems to collect, analyse, and disseminate ERP data. Objectives: (i) To consolidate relevant ERP variables into a singular data universe; (ii) To create an accessible and intuitive query tool for rapid data retrieval. Method: We reviewed nine established individual team databases to identify common variables to create one standard ERP data dictionary. To address data automation, we used a third-party business intelligence tool to map identified variables within the EHR system, consolidating variables into a single ERP universe. To determine efficacy, we compared times for four experienced research coordinators to use manual, five-universe, and ERP Universe processes to retrieve ERP data for 10 randomly selected surgery patients. Results: The total times to process data variables for all 10 patients for the manual, five universe, and ERP Universe processes were 510, 111, and 76 min, respectively. Shifting from the five-universe or manual process to the ERP Universe resulted in decreases in time of 32% and 85%, respectively. Conclusion: The ERP Universe improves time spent collecting, analysing, and reporting ERP elements without increasing operational costs or interrupting workflow. Implications: Manual data abstraction places significant burden on resources. The creation of a singular instrument dedicated to ERP data abstraction greatly increases the efficiency in which clinicians and supporting staff can query adherence to an ERP protocol.

Unsupervised machine learning can delineate central sulcus by using the spatiotemporal characteristic of somatosensory evoked potentials.

Objective.Somatosensory evoked potentials (SSEPs) recorded with electrocorticography (ECoG) for central sulcus (CS) identification is a widely accepted procedure in routine intraoperative neurophysiological monitoring. Clinical practices test the short-latency SSEPs for the phase reversal over strip electrodes. However, assessments based on waveform morphology are susceptible to variations in interpretations due to the hand area's localized nature and usually require multiple electrode placements or electrode relocation. We investigated the feasibility of unsupervised delineation of the CS by using the spatiotemporal patterns of the SSEP captured with the ECoG grid.Approach. Intraoperatively, SSEPs were recorded from eight patients using ECoG grids placed over the sensorimotor cortex. Neurosurgeons blinded to the electrophysiology identified the sensory and motor gyri using neuronavigation based on sulcal anatomy. We quantified the most discriminatory time points in SSEPs temporal profile between the primary motor (M1) and somatosensory (S1) cortex using the Fisher discrimination criterion. We visualized the amplitude gradient of the SSEP over a 2D heat map to provide visual feedback for the delineation of the CS based on electrophysiology. Subsequently, we employed spectral clustering using the entire the SSEP waveform without selecting any time points and grouped ECoG channels in an unsupervised fashion.Main results.Consistently in all patients, two different time points provided almost equal discrimination between anterior and posterior channels, which vividly outlined the CS when we viewed the SSEP amplitude distribution as a spatial 2D heat map. The first discriminative time point was in proximity to the conventionally favored ∼20 ms peak (N20), and the second time point was slightly later than the markedly high ∼30 ms peak (P30). Still, the location of these time points varied noticeably across subjects. Unsupervised clustering approach separated the anterior and posterior channels with an accuracy of 96.3% based on the time derivative of the SSEP trace without the need for a subject-specific time point selection. In contrast, the raw trace resulted in an accuracy of 88.0%.Significance. We show that the unsupervised clustering of the SSEP trace assessed with subdural electrode grids can delineate the CS automatically with high precision, and the constructed heat maps can localize the motor cortex. We anticipate that the spatiotemporal patterns of SSEP fused with machine learning can serve as a useful tool to assist in surgical planning.

Impact of anesthesia and analgesia techniques on glioblastoma progression. A narrative review.

Glioblastoma (GBM) is an aggressive malignant CNS tumor with a median survival of 15 months after diagnosis. Standard therapy for GBM includes surgical resection, radiation, and temozolomide. Recently, anesthetics and analgesics have received attention for their potential involvement in mediating tumor growth. This narrative review investigated whether various members of the 2 aforementioned classes of drugs have a definitive impact on GBM progression by summarizing pertinent in vitro, in vivo, and clinical studies. Recent publications regarding general anesthetics have been inconsistent, showing that they can be pro-tumoral or antitumoral depending on the experimental context. The local anesthetic lidocaine has shown consistent antitumoral effects in vitro. Clinical studies looking at anesthetics have not concluded that their use improves patient outcomes. In vitro and in vivo studies looking at opioid involvement in GBM have demonstrated inconsistent findings regarding whether these drugs are pro-tumoral or antitumoral. Nonsteroidal anti-inflammatory drugs, and specifically COX-2 inhibitors, have shown inconsistent findings across multiple studies looking at whether they are beneficial in halting GBM progression. Until multiple repeatable studies show that anesthetics and analgesics can suppress GBM growth, there is no strong evidence to recommend changes in the anesthetic care of these patients.

Power Modulations of ECoG Alpha/Beta and Gamma Bands Correlate With Time-Derivative of Force During Hand Grasp.

It is well-known that motor cortical oscillatory components are modulated in their amplitude during voluntary and imagined movements. These patterns have been used to develop brain-machine interfaces (BMI) which focused mostly on movement kinematics. In contrast, there have been only a few studies on the relation between brain oscillatory activity and the control of force, in particular, grasping force, which is of primary importance for common daily activities. In this study, we recorded intraoperative high-density electrocorticography (ECoG) from the sensorimotor cortex of four patients while they executed a voluntary isometric hand grasp following verbal instruction. The grasp was held for 2 to 3 s before being instructed to relax. We studied the power modulations of neural oscillations during the whole time-course of the grasp (onset, hold, and offset phases). Phasic event-related desynchronization (ERD) in the low-frequency band (LFB) from 8 to 32 Hz and event-related synchronization (ERS) in the high-frequency band (HFB) from 60 to 200 Hz were observed at grasp onset and offset. However, during the grasp holding period, the magnitude of LFB-ERD and HFB-ERS decreased near or at the baseline level. Overall, LFB-ERD and HFB-ERS show phasic characteristics related to the changes of grasp force (onset/offset) in all four patients. More precisely, the fluctuations of HFB-ERS primarily, and of LFB-ERD to a lesser extent, correlated with the time-course of the first time-derivative of force (yank), rather than with force itself. To the best of our knowledge, this is the first study that establishes such a correlation. These results have fundamental implications for the decoding of grasp in brain oscillatory activity-based neuroprosthetics.

Implementation of an Enhanced Recovery After Spine Surgery program at a large cancer center: a preliminary analysis.

This study describes the implementation of a multimodal, multidisciplinary, evidence-based ERAS program in oncologic spine surgery, identifies and measures several relevant postoperative recovery outcomes, and demonstrates the feasibility and potential benefit of the program in improving analgesia and decreasing opioid consumption. The study underscores the importance of defining and capturing meaningful, patient-specific, and patient-reported outcomes, and constant evaluation and monitoring of a group's compliance with the program. The study represents the steppingstone for evaluation and improvement of a young ERAS program for spine surgery and serves as a roadmap for further initiatives and larger-scale studies.

Scalp blocks for brain tumor craniotomies: A retrospective survival analysis of a propensity match cohort of patients.

To test the association between the use of scalp blocks for malignant brain tumor craniotomy and survival. This is a retrospective study conducted in a tertiary academic center. Demographic, intraoperative and survival data from 808 adult patients with malignant brain tumors was included in the analysis. Patients were divided in those who received an Intraoperative use of scalp block or not. The progression free survival (PFS) and overall survival (OS) rates were compared in patients who had and had not scalp blocks. Kaplan-Meier method was used for time-to-event analysis including recurrence free survival and overall survival. Multivariate analyses before and after propensity score matching were conducted to test the association between different covariates including scalp blocks with PFS and OS. Five hundred and ninety (73%) of the patients had a scalp block. Before PSM, patients with a scalp block were more likely to have an ASA physical status of 3-4, recurrent tumors and receive adjuvant radiation. Patients with scalp block showed no significant reduction in intraoperative opioids. After adjusting for significant covariates, the administration of a scalp block was not associated with an increase in PFS (HR, 95%CI = 0.98, 0.8-1.2, p = 0.892) or OS (HR, 95%CI = 1.02, 0.82-1.26, p = 0.847) survival. This retrospective study suggests that the use of scalp blocks during brain tumor surgery is not associated with patients' longer survival.

Association between intravenous acetaminophen and reduction in intraoperative opioid consumption during transsphenoidal surgery for pituitary tumors.

BACKGROUND AND AIMS: Pain during and after transsphenoidal surgeries originates from stimulation of branches of the trigeminal cranial nerve that supply the inner aspect of the nose cavity and dura mater. Thereby, patients undergoing transsphenoidal surgery may require moderate-to-large amounts of analgesics including opioids. Intravenous acetaminophen provides analgesia and reduces opioid consumption for a wide variety of surgeries. We hypothesized that the use of intravenous acetaminophen is associated with a reduction in intraoperative opioid consumption and provides significant analgesia during and after transsphenoidal surgery. MATERIAL AND METHODS: This retrospective study included 413 patients who underwent transsphenoidal surgery for pituitary adenomas. The primary outcome of this study was intraoperative opioid consumption. Secondary outcomes included pain intensity, Richmond Agitation Sedation Scale scores, and nausea and vomiting upon arrival to postoperative anesthesia care unit. Patients were divided into two groups based on the intraoperative acetaminophen use. A prospensity score matching analysis was used to balance for important variables between the two groups of treatment. Regression models were fitted after matching the covariates. A P < 0.05 was considered statistically significant. RESULTS: After matching, 126 patients were included in each group of treatment. Patients in the acetaminophen group required significantly less amount (a decrease by 14.9%) of opioids during surgery than those in the non-acetaminophen group. Postoperative pain, postoperative nausea and vomiting, and sedation scores were not significantly different between patients who received intravenous acetaminophen and those who did not. CONCLUSION: Intravenous acetaminophen is associated with a reduction in intraoperative opioids during transsphenoidal pituitary surgery.

Association Between Perioperative Hyperglycemia and Survival in Patients With Glioblastoma.

BACKGROUND: Several studies have examined the association between hyperglycemia in the first 10 to 12 weeks following surgery and postoperative survival in glioblastoma multiforme (GBM) patients. We hypothesize that episodes of hyperglycemia before, during and/or following surgery for primary GBM are independent predictors of disease progression and mortality. MATERIALS AND METHODS: A total of 162 adult patients were included in the analysis. All patients received adjuvant temozolamide. The progression free survival (PFS) and overall survival (OS) rates at 1 and 5 years were analyzed using different glycemic cutoff values. Multivariate analyses were conducted to test the association between preoperative, intraoperative and postoperative hyperglycemia with PFS and OS. RESULTS: Kaplan-Meier curves revealed a trend toward increased PFS and OS with lower glucose concentrations with the exception of glucose concentrations >180 mg/dL in the intraoperative/postoperative day 0 time period. Univariate analysis of blood glucose levels did not demonstrate a statistically significant effect on PFS in any time period, however hyperglycemia was statistically significant for OS in the preoperative time period. Although, multivariate analysis showed no statistically significant association with hyperglycemia on PFS, a statistically significant decrease in OS was seen for plasma glucose concentrations >112 mg/dL (P=0.01) and >180 mg/dL (P=0.01) in the preoperative period. There was a decreasing effect on OS with blood glucose concentrations greater than the median in multiple time periods (P=0.02). CONCLUSIONS: Preoperative hyperglycemia is associated with poor OS after GBM surgery.

Spinal Laser Interstitial Thermal Therapy: A Novel Alternative to Surgery for Metastatic Epidural Spinal Cord Compression.

BACKGROUND: Although surgery followed by radiation effectively treats metastatic epidural compression, the ideal surgical approach should enable fast recovery and rapid institution of radiation and systemic therapy directed at the primary tumor. OBJECTIVE: To assess spinal laser interstitial thermotherapy (SLITT) as an alternative to surgery monitored in real time by thermal magnetic resonance (MR) images. METHODS: Patients referred for spinal metastasis without motor deficits underwent MR-guided SLITT, followed by stereotactic radiosurgery. Clinical and radiological data were gathered prospectively, according to routine practice. RESULTS: MR imaging-guided SLITT was performed on 19 patients with metastatic epidural compression. No procedures were discontinued because of technical difficulties, and no permanent neurological injuries occurred. The median follow-up duration was 28 weeks (range 10-64 weeks). Systemic therapy was not interrupted to perform the procedures. The mean preoperative visual analog scale scores of 4.72 (SD ± 0.67) decreased to 2.56 (SD ± 0.71, P = .043) at 1 month and remained improved from baseline at 3.25 (SD ± 0.75, P = .021) 3 months after the procedure. The preoperative mean EQ-5D index for quality of life was 0.67 (SD ± 0.07) and remained without significant change at 1 month 0.79 (SD ± 0.06, P = .317) and improved at 3 months 0.83 (SD ± 0.06, P = .04) after SLITT. Follow-up MR imaging after 2 months revealed significant decompression of the neural component in 16 patients. However, 3 patients showed progression at follow-up, 1 was treated with surgical decompression and stabilization and 2 were treated with repeated SLITT. CONCLUSION: MR-guided SLITT can be both a feasible and safe alternative to separation surgery in carefully selected cases of spinal metastatic tumor epidural compression. ABBREVIATIONS: cEBRT, conventional external beam radiation therapyESCC, epidural spinal cord compressionSLITT, spinal laser interstitial thermotherapySSRS, stereotactic spinal radiosurgeryVAS, visual analog scale.

Enhanced recovery after surgery for oncological craniotomies.

Enhanced recovery after surgery (ERAS) initiatives in the fields of gastrointestinal and pelvic surgery have contributed to improved postoperative functional status for patients and decreased length of stay. A similar comprehensive protocol is lacking for patients undergoing craniotomy for tumor resection. A literature search was performed using PubMed. These references were reviewed with a preference for recent high quality studies. Cohort and retrospective studies were also included if higher levels of evidence were lacking. A literature search was conducted for scalp blocks and minimally invasive craniotomies. Papers were scored using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria for evidence level and recommendation grade. Seventeen ERAS items were reviewed and recommendations made. The current body of evidence is insufficient to create a standardized protocol for craniotomy and tumor resection. However, this initial review of the literature supports pursuing future research initiatives that explore modalities to improve functional recovery and decrease length of stay in craniotomy patients.