Dynamic Cortical Connectivity During Propofol Sedation in Glioma Patients.

BACKGROUND: The behavioral manifestations and neurophysiological responses to sedation can assist in understanding brain function after neurological damage, and can be described by cortical functional connectivity. Glioma patients may experience neurological deficits that are not clinically detectable before sedation. We hypothesized that patients with gliomas exhibit distinct cortical connectivity patterns compared to non-neurosurgical patients during sedation. METHODS: This is a secondary analysis of a previously published prospective observational study. Patients scheduled for resection of supratentorial glioma (n=21) or a non-neurosurgical procedure (n=21) under general anesthesia were included in this study. Frontal electroencephalography (EEG) signals were recorded at different sedation levels as assessed by the Observer Assessment of Alertness/Sedation (OAA/S) score. Kernel principal component analysis and k-means clustering were used to determine possible temporal dynamics from the weighted phase lag index characteristics. RESULTS: Ten EEG connectivity states were identified by clustering (76% consistency), each with unique properties. At OAA/S 3, the median (Q1, Q3) occurrence rates of state 6 (glioma group, 0.110 [0.083, 0.155] vs. control group, 0.070 [0.030, 0.110]; P=0.008) and state 7 (glioma group, 0.105 [0.083, 0.148] vs. control group: 0.065 [0.038, 0.090]; P=0.001), which are dominated by beta connectivity, were significantly different between the 2 groups, reflecting differential conversion of the beta band between the left and right brain regions. In addition, the temporal dynamics of the brain's functional connectivity was also reflected in the transition relationships between metastable states. CONCLUSIONS: There were differences in EEG functional connectivity, which is dynamic, between the glioma and nonglioma groups during sedation.

Anesthesia on Clinical Outcomes in an Extended Time Window During Endovascular Stroke Therapy: Exploratory Analysis of the ANGEL-ACT Registry.

OBJECTIVE: Data on the impact of different anesthesia methods on clinical outcomes in patients with acute ischemic stroke undergoing endovascular therapy (EVT) in extended windows are limited. This study compared clinical outcomes in patients with stroke having general anesthesia (GA), conscious sedation (CS), or local anesthesia (LA) during EVT in extended (>6 h) time windows. METHODS: We conducted an exploratory analysis of data from the ANGEL-ACT registry. The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Secondary outcomes included the proportions of patients with mRS scores of 0 to 1, 0 to 2, and 0 to 3, and safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH, or mortality within 90 days. Multivariate analyses, inverse probability of treatment weighting, and coarsened exact matching were used to adjust for indication bias. RESULTS: A total of 646 patients were included in the analysis (GA,280; CS, 103; LA, 263). Patients having LA during EVT were more likely to have a favorable mRS score (adjusted odds ratio [aOR]: 1.75; 95% CI: 1.28 to 2.40) and a lower incidence of symptomatic ICH (aOR: 0.33; 95% CI: 0.14 to 0.76) than those having GA group. Similarly, CS was associated with greater odds of favorable 90-day mRS scores compared with GA (aOR: 1.69; 95% CI: 1.11 to 2.56). Posterior circulation stroke was overrepresented in the GA group (29.6%) and may be a reason for the worse outcomes in the GA group. CONCLUSIONS: Patients who received LA or CS had better neurological outcomes than those who received GA within extended time windows in a real-world setting.

General anesthesia versus nongeneral anesthesia during endovascular therapy for acute ischemic stroke: A systematic review and meta-analysis.

OBJECTIVE: This study compares the safety and efficacy of general anesthesia (GA) and nongeneral anesthesia (non-GA) on functional outcomes in patients receiving endovascular therapy for ischemic stroke. METHODS: All available studies on the anesthetic management of patients with acute ischemic stroke in PubMed, the Cochrane Central Register of Controlled Trials, and Embase were included. We also compared the clinical outcomes in the studies with subgroup analyses of the occlusion site (anterior vs. posterior circulation) and preretriever group versus retriever group. Functional independence, mortality, successful recanalization, hemodynamic instability, intracerebral hemorrhage, and respiratory complications were considered primary or secondary outcomes. RESULTS: A total of 24,606 patients in 60 studies were included. GA had a lower risk of 90-day functional independence (OR = 0.67, 95% CI 0.58 to 0.77), higher risk of 90-day mortality (OR = 1.29; 95% CI 1.15 to 1.45), and successful reperfusion (OR = 1.18; 95% CI 1.94 to 6.82). However, there were no differences in functional independence and mortality between GA and non-GA at 90 days after the procedure. CONCLUSION: The study shows poorer results in the GA group, which may be due to the inclusion of nonrandomized studies. However, analysis of the RCTs suggested that the outcomes do not differ between the two groups (GA vs. non-GA). Thus, general anesthesia is as safe as nongeneral anesthesia under standardized management.

Effect of intraoperative muscle relaxation reversal on the success rate of motor evoked potential recording in patients undergoing spinal surgery: a randomized controlled trial.

BACKGROUND: Partial neuromuscular blockade (NMB) has been applied for some surgeries to reduce bleeding and prevent patient movement for spinal surgery. Sugammadex selectively binds to rocuronium in the plasma and consequently lowers the rocuronium concentration at the neuromuscular junction. In this study, we aimed to observe whether the success rate of transcranial motor-evoked potential (TceMEP) can be increased by sugammadex compared with partial NMB during spinal surgery. METHODS: Patients who underwent elective spinal surgery with TceMEP monitoring were randomly assigned to the sugammadex group and control group. Rocuronium was continuously infused to maintain the train of four counts (TOFc) = 2. The sugammadex group discontinued rocuronium infusion at the time of TceMEP monitoring and was infused with 2 mg/kg sugammadex; the control group was infused with the same dose of saline. RESULTS: A total of 171 patients were included. The success rate of TceMEP monitoring in the sugammadex group was significantly higher than that in the control group. TceMEP amplitudes were greater in the sugammadex group than in the control group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. The latencies of upper extremity TceMEPs monitoring showed no difference between groups. TOF ratios were greater in the sugammadex group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. There were no adverse effects caused by sugammadex. CONCLUSIONS: Sugammadex can improve the success rate of motor-evoked potential monitoring compared with moderate neuromuscular blockade induced by continuous infusion of rocuronium in spinal surgery. TRIAL REGISTRATION: The study was registered on clinicaltrials.gov.cn on 29/10/2020 (trial registration number: NCT04608682).

Association of Admission Glucose and Outcomes After Endovascular Treatment for Acute Stroke: Data From the ANGEL-ACT Registry.

BACKGROUND: The association between admission glucose levels and clinical outcomes after stroke has not been effectively elucidated. This study assessed the association among admission glucose levels, admission hyperglycemia, diabetes mellitus, and 90-day neurological outcomes in patients with acute ischemic stroke undergoing endovascular therapy. METHODS: The ANGEL-ACT registry enrolled adults with acute ischemic stroke undergoing endovascular therapy between 2017 and 2019 in China and patients with available admission glucose data were included. Restricted cubic spline regression was used to determine the knots of blood glucose levels. Binary or ordinal logistic regression models were used to examine the impact of different admission glucose levels on neurological outcomes and 90-day mortality. RESULTS: In total, 1684 participants with available admission glucose concentrations were evaluated. The admission glucose level was divided into 4 levels according to the restricted cubic spline curves: level 1 (<5.3 mmol/L), level 2 (5.3 to 7.0 mmol/L), level 3 (7.0 to 11.6 mmol/L), and level 4 (≥11.6 mmol/L). Level 4 admission glucose was associated with a decreased incidence of a modified Rankin scale score of 0 to 2 (hazard ratio, 0.59; 95% CI, 0.40-0.87) and an increased risk of mortality (hazard ratio, 1.74; 95% CI, 1.06-2.85). Levels 3 and 4, hyperglycemia, and diabetes mellitus independently predicted symptomatic intracranial hemorrhage (sICH). Admission glucose levels showed J-shaped relationships with sICH. CONCLUSIONS: Higher admission glucose levels (≥11.6 mmol/L) were associated with a decreased likelihood of a modified Rankin scale score of 0 to 2 and an increased risk of mortality and sICH.

Effect of driving pressure on early postoperative lung gas distribution in supratentorial craniotomy: a randomized controlled trial.

BACKGROUND: Neurosurgical patients represent a high-risk population for postoperative pulmonary complications (PPCs). A lower intraoperative driving pressure (DP) is related to a reduction in postoperative pulmonary complications. We hypothesized that driving pressure-guided ventilation during supratentorial craniotomy might lead to a more homogeneous gas distribution in the lung postoperatively. METHODS: This was a randomized trial conducted between June 2020 and July 2021 at Beijing Tiantan Hospital. Fifty-three patients undergoing supratentorial craniotomy were randomly divided into the titration group or control group at a ratio of 1 to 1. The control group received 5 cmH2O PEEP, and the titration group received individualized PEEP targeting the lowest DP. The primary outcome was the global inhomogeneity index (GI) immediately after extubation obtained by electrical impedance tomography (EIT). The secondary outcomes were lung ultrasonography scores (LUSs), respiratory system compliance, the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2) and PPCs within 3 days postoperatively. RESULTS: Fifty-one patients were included in the analysis. The median (IQR [range]) DP in the titration group versus the control group was 10 (9-12 [7-13]) cmH2O vs. 11 (10-12 [7-13]) cmH2O, respectively (P = 0.040). The GI tract did not differ between groups immediately after extubation (P = 0.080). The LUSS was significantly lower in the titration group than in the control group immediately after tracheal extubation (1 [0-3] vs. 3 [1-6], P = 0.045). The compliance in the titration group was higher than that in the control group at 1 h after intubation (48 [42-54] vs. 41 [37-46] ml·cmH2O-1, P = 0.011) and at the end of surgery (46 [42-51] vs. 41 [37-44] ml·cmH2O-1, P = 0.029). The PaO2/FiO2 ratio was not significantly different between groups in terms of the ventilation protocol (P = 0.117). At the 3-day follow-up, no postoperative pulmonary complications occurred in either group. CONCLUSIONS: Driving pressure-guided ventilation during supratentorial craniotomy did not contribute to postoperative homogeneous aeration, but it may lead to improved respiratory compliance and lower lung ultrasonography scores. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT04421976.

Early stellate ganglion block for improvement of postoperative cerebral blood flow velocity after aneurysmal subarachnoid hemorrhage: results of a pilot randomized controlled trial.

OBJECTIVE: Stellate ganglion block (SGB) is a commonly used sympathetic nerve block technique that may have benefits for patients with aneurysmal subarachnoid hemorrhage (aSAH) in the early stage. Cerebral vasospasm (CVS), one of the most common complications of aSAH, is accompanied by an abnormal increase in cerebral blood flow velocity (CBFV) and neurological dysfunction. In this pilot study the authors sought to determine the feasibility of early SGB for CVS in aSAH patients by observing the incidence of symptomatic CVS. METHODS: Prior to receiving surgical treatment, patients with aSAH were randomly assigned to the SGB group or the non-SGB group. The primary outcome was the incidence of symptomatic CVS within 14 ± 2 days after the onset of aSAH. As a higher CBFV is often associated with CVS and a poor prognosis, the mean CBFV of the middle cerebral artery was observed immediately after surgery and on postoperative days 1, 2, 3, 5, and 7. Other secondary outcomes included transcranial Doppler (TCD)/CTA-type CVS, delayed cerebral ischemia during hospitalization, new cerebral infarction within 3 months, adverse events (AEs), and clinical prognosis. RESULTS: Symptomatic CVS occurred in 40% of patients in the non-SGB group and in 20% in the SGB group (RR 0.50, 95% CI 0.22-1.16). Continuous TCD sonography revealed that the postoperative mean CBFV was lower in the SGB group than in the non-SGB group (F = 3.608, p = 0.02). In addition, the percentages of patients with CVS evaluated by TCD (TCD-CVS) and total new infarctions within 3 months were also significantly lower than those in patients with CVS (TCD-CVS 36.7% vs 70%, RR 0.52, 95% CI 0.31-0.89, and total new infarctions 26.7% vs 53.3%, RR 0.50, 95% CI 0.25-0.99). In terms of AEs and mortality, there were no significant differences between the two groups. CONCLUSIONS: This pilot study demonstrated for the first time, to the authors' knowledge, that early SGB is feasible and has the potential to reduce the risk of CVS and improve the prognosis of aSAH. This method may be a new treatment for patients with aSAH that may have more advantages than traditional therapeutic drugs and is worth further study. Clinical trial registration no.: NCT04691271 (ClinicalTrials.gov).

Brain relaxation using desflurane anesthesia and total intravenous anesthesia in patients undergoing craniotomy for supratentorial tumors: a randomized controlled study.

BACKGROUND: Satisfactory brain relaxation is essential in neurosurgery. Desflurane anesthesia and propofol-based total intravenous anesthesia (TIVA) have different effects on cerebral hemodynamics, potentially contributing to discrepant brain relaxation. The purpose of this study was to compare the effects of desflurane and TIVA on brain relaxation in patients undergoing craniotomy for supratentorial tumors. METHODS: In this randomized, controlled study, we enrolled patients aged 18-60 years, with ASA I-III, who were scheduled to undergo elective craniotomy for supratentorial tumors. Patients were randomly assigned in a 1:1 ratio to receive desflurane anesthesia or TIVA. The primary outcome was the proportion of satisfactory brain relaxation. Secondary outcomes included emergence and extubation times, recovery of cognitive function and postoperative complications. RESULTS: Of 369 patients who were assessed for eligibility, 111 were randomized and 110 were included in the modified intention-to-treat analysis (55 in the desflurane group and 55 in the TIVA group). The proportion of satisfactory brain relaxation was similar between the two groups: 69% in the desflurane group and 73% in the TIVA group (RR: 0.950, 95% CI: 0.748-1.207; P = 0.675). Patients assigned to the desflurane group had shorter emergence (10 [8-13] min vs. 13 [10-20] min, P < 0.001) and extubation times (13 [10-18] min vs. 17 [13-23] min, P < 0.001), and better recovery of cognitive function at 15 min after extubation (16 [0-24] vs. 0 [0-20], P = 0.003), but experienced increased postoperative nausea and vomiting (PONV) (16 [29%] vs. 6 [11%] P = 0.017) and tachycardia (22 [40%] vs. 9 [16%], P = 0.006) during recovery. CONCLUSIONS: Desflurane anesthesia and TIVA provide similar brain relaxation in patients without intracranial hypertension undergoing elective craniotomy. Desflurane accelerates the recovery from anesthesia but is associated with increased PONV and tachycardia during the recovery period. TRIAL REGISTRATION: Clinicaltrial.gov (NCT04691128). Date of registration: December 31, 2020.

Effect of Sugammadex During Transcranial Electrical Motor Evoked Potentials Monitoring in Spinal Surgery: A Randomized Controlled Trial.

INTRODUCTION: Neuromuscular blockade suppresses transcranial electrical motor evoked potential (TceMEP) amplitude and is usually avoided during TceMEP monitoring. In this randomized controlled trial, we investigated whether rocuronium-induced suppression of TceMEP amplitude could be reversed by sugammadex in patients undergoing spine surgery. METHODS: Seventy-six patients undergoing spinal surgery were randomly allocated into sugammadex and control groups. In the sugammadex group, a rocuronium infusion was titrated to maintain moderate neuromuscular blockade (2 twitches on train-of-four) until dural opening when the rocuronium infusion was discontinued and 2 mg/kg sugammadex administered. In the control group, no neuromuscular blockade was administered after induction of anesthesia. The primary outcome was a comparison between sugammadex and control groups of mean TceMEP amplitudes in the abductor pollicis brevis muscles of both upper extremities 5 minutes after dural. Secondary outcomes included TceMEP amplitudes at 10, 20, 30, and 60 minutes after dural opening. RESULTS: Sixty-six patients were included in the analysis. TceMEP amplitudes were significantly greater in the sugammadex group (629 µV, interquartile range: 987 µV) than in the control group (502 µV, interquartile range: 577 µV; P =0.033) at 5 minutes after dural opening. TceMEP amplitudes were also greater in the sugammadex group at 10 minutes ( P =0.0010), 20 minutes ( P =0.003), 30 minutes ( P =0.001), and 60 minutes ( P =0.003) after dural opening. CONCLUSIONS: Moderate neuromuscular blockade induced by continuous infusion of rocuronium was effectively reversed by sugammadex. This suggests that sugammadex could be used to enhance TceMEP waveform monitoring during spine surgery requiring muscle relaxation.

General Anesthesia Versus Nongeneral Anesthesia for Patients With Acute Posterior Circulation Stroke Undergoing Endovascular Therapy: A Systematic Review and Meta-analysis.

There is continued controversy regarding the optimal anesthetic technique for endovascular therapy in patients with acute posterior circulation ischemic stroke. To compare the clinical outcomes general anesthesia (GA) and non-GA, we performed a systematic review and meta-analysis of randomized controlled trials and observational studies focused on the anesthetic management for endovascular therapy in patients with acute posterior circulation stroke, without language restriction. In addition, we compared clinical outcomes among the studies with different non-GA types (conscious sedation or local anesthesia). Outcome variables were functional independence, excellent outcomes, favorable outcomes, mortality, successful recanalization, hemodynamic instability, intracerebral hemorrhage, and respiratory or vascular complications. Eight studies including 1777 patients were identified. Although GA was associated with a lower odds of functional independence at 90 days (odds ratio [OR]: 0.55; 95% confidence interval [CI] 0.38 to 0.81; P =0.009), substantial heterogeneity was noted ( I2 =65%). Subgroup analysis showed that GA was associated with higher odds of mortality than conscious sedation (OR: 1.83; 95% CI, 1.30 to 2.57; I2 =0%), but there was no difference between GA and local anesthesia ( I2 =0%). Interestingly, subgroup analysis did not identify a relationship between functional independence and GA compared with local anesthesia (OR: 0.90; 95% CI, 0.64 to 1.25; P =0.919; I2 =0%). This meta-analysis demonstrates that GA is associated with worse outcomes in patients with acute posterior circulation stroke undergoing endovascular therapy based on current studies.

General Anesthesia vs Conscious Sedation for Endovascular Treatment in Patients With Posterior Circulation Acute Ischemic Stroke: An Exploratory Randomized Clinical Trial.

Importance: No definitive conclusion can be made on the best choice of anesthesia for people with acute posterior circulation stroke during endovascular treatment. Only a few observational studies have focused on this topic in recent years, and they have differing conclusions. Objective: To examine whether conscious sedation (CS) is a feasible alternative to general anesthesia (GA) during endovascular treatment in patients with acute posterior circulation stroke. Design, Setting, and Participants: A randomized parallel-group exploratory trial with blinded end point evaluation (Choice of Anesthesia for Endovascular Treatment of Acute Ischemic Stroke [CANVAS II]) enrolled adult patients from March 2018 to June 2021 at 2 comprehensive care hospitals in China. Patients with acute posterior circulation stroke were enrolled, randomized, and monitored for 3 months. Of 210 patients admitted with acute ischemic posterior circulation stroke, 93 were recruited and 87 were included in the intention-to-treat (ITT) analysis after exclusions, 43 were assigned to GA and 44 to CS. All analyses were unadjusted or adjusted with the ITT principle. Interventions: Participants were randomly assigned to CS or GA in a 1:1 ratio. Main Outcomes and Measures: The primary end point was functional independence at 90 days evaluated with the modified Rankin Scale (mRS). Results: A total of 87 participants were included in the ITT study (mean [SD] age, 62 [12] years; 16 [18.4%] female and 71 [81.6%] male). Of these, 43 were in the GA group and 44 in the CS group. The overall baseline median (IQR) National Institute of Health Stroke Scale (NIHSS) score was 15 (12-17). In the CS group, 13 people (29.5%) were ultimately transferred to GA. The CS group had a higher incidence of functional independence; however, no significant difference was found between the 2 groups (48.8% vs 54.5%; risk ratio, 0.89; 95% CI, 0.58-1.38; adjusted odds ratio [OR], 0.91; 95% CI, 0.37-2.22). However, GA performed better in successful reperfusion (mTICI 2b-3) under ITT analysis (95.3% vs 77.3%; adjusted OR, 5.86; 95% CI, 1.16-29.53). Conclusion and Relevance: The findings in this study suggest that CS was not better than GA for the primary outcome of functional recovery and was perhaps worse for the secondary outcome of successful reperfusion. Trial Registration: ClinicalTrials.gov Identifier: NCT03317535.

Effect of early stellate ganglion block in cerebral vasospasm after aneurysmal subarachnoid hemorrhage (BLOCK-CVS): study protocol for a randomized controlled trial.

INTRODUCTION: Stellate ganglion block has been reported to expand cerebral vessels and alleviate vasospasm after aneurysmal subarachnoid hemorrhage. However, the causal relationship between early stellate ganglion block and cerebral vasospasm prevention has not yet been established. The purpose of this study was to explore the effectiveness and safety of early stellate ganglion block as a preventive treatment for cerebral vasospasm and delayed cerebral ischemia. METHODS/DESIGN: This is a single-center, prospective, randomized, controlled, blinded endpoint assessment superiority trial. A total of 228 patients will be randomized within 48 h of aneurysmal subarachnoid hemorrhage onset in a 1:1 ratio into two groups, one group receiving an additional e-SGB and the other group receiving only a camouflaging action before anesthesia induction in the operating room. The primary outcome is the incidence of symptomatic vasospasm within 14 days after aSAH. Further safety and efficacy parameters include the incidence of radiographic vasospasm, new cerebral infarction, postoperative delirium, and complications up to 90 days after surgery; postoperative cerebral hemodynamics; Mini-Mental State Examination score; modified Rankin scale score; and all-cause mortality up to 90 days after surgery. DISCUSSION: This is a randomized controlled trial to explore the effectiveness and safety of early stellate ganglion block as a preventive treatment to reduce cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage. If the results are positive, it may provide a new direction for the prevention and treatment of cerebral vasospasm and delayed cerebral ischemia. TRIAL REGISTRATION: The study was registered on Clincaltrials.gov on December 13, 2020 (NCT04691271).

Factors associated with artificial airway retention after skull base chordoma resection: A retrospective cohort study.

Background: Chordoma is a malignant bone and soft tissue tumor derived from embryonic notochord remnants, and skull base chordoma accounts for ~1/3 of all chordoma cases. Skull base chordoma is closely related to the brainstem and cranial nerves and has a high recurrence rate. The purpose of this study was to investigate the influence of the timing of tracheal extubation on perioperative pulmonary complications. We also aimed to explore predictors of postoperative artificial airway (AA) retention in patients with skull base chordoma. Methods: This was a single-center, retrospective cohort study. The study population included all skull base chordoma patients undergoing surgical treatment between January 2019 and December 2021 at Beijing Tiantan Hospital. The primary outcome was the incidence of postoperative pulmonary complications. Several patient characteristics were evaluated for potential associations with AA retention. Results: A total of 310 patients with skull base chordoma were enrolled. The frequency of AA retention after surgery for skull base chordoma was 30.97%. The incidence of postoperative pulmonary complications was much lower in those without AA retention (3.74 vs. 39.58%, P < 0.001). Factors with the highest point estimates for the odds of AA retention included body mass index, cranial nerve involvement, maximum tumor diameter, operative method, hemorrhage volume, operative duration and intraoperative mechanical ventilation duration. Conclusions: In this retrospective cohort study, most of the factors associated with postoperative airway retention were closely related to the patient's tumor characteristics. These data demonstrate that respiratory management in patients with skull base chordoma remains an ongoing concern.

Effect of intraoperative muscle relaxation reversal on the success rate of motor-evoked potential recording in patients undergoing spinal surgery: study protocol for a randomised controlled trial.

INTRODUCTION: Transcranial motor-evoked potentials (TceMEPs) is conventionally performed without neuromuscular blockade (NMB) because of its potential interference with neuromuscular junction and signal interpretation. Sugammadex is the first highly selective antagonist that binds to rocuronium and can rapidly and effectively reverse NMB. This study aims to evaluate the success rate of intraoperative muscle relax reversal by sugammadex on intraoperative TceMEP recording. METHODS AND ANALYSIS: We will conduct a single-centre randomised controlled study. In total, 162 patients undergoing thoracic or lumbar spinal surgery will be randomly divided into the sugammadex group or control group at a ratio of 1:1. Total intravenous anaesthesia by propofol and remifentanil will be performed in both groups. In the sugammadex group, patients will receive continuous infusion of rocuronium to produce a blockade maintained for at least two twitches in train-of-four, rocuronium infusion will be discontinued and 2 mg/kg sugammadex will be given while performing TceMEPs monitoring. In the control group, rocuronium infusion will be discontinued and the same volume of saline will be infused while performing TceMEPs monitoring. The primary aim of this study is to evaluate the success rate of TceMEPs recording between two groups. ETHICS AND DISSEMINATION: The approval for the study was certificated by the Ethical Committee of Beijing Tiantan Hospital, Capital Medical University on, 16 July 2021 (KY2021-082-02). The study was registered on clincaltrials.gov on 25 October 2020. Our study might guide neuromuscular blockade plans in TceMEPs monitoring undergoing spinal surgery. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conference. TRIAL REGISTRATION NUMBER: NCT04608682.

Awake craniotomy for auditory brainstem implant in patients with neurofibromatosis type 2: Four case reports.

BACKGROUND: The auditory brainstem implant (ABI) is a significant treatment to restore hearing sensations for neurofibromatosis type 2 (NF2) patients. However, there is no ideal method in assisting the placement of ABIs. In this case series, intraoperative cochlear nucleus mapping was performed in awake craniotomy to help guide the placement of the electrode array. CASE SUMMARY: We applied the asleep-awake-asleep technique for awake craniotomy and hearing test via the retrosigmoid approach for acoustic neuroma resections and ABIs, using mechanical ventilation with a laryngeal mask during the asleep phases, utilizing a ropivacaine-based regional anesthesia, and sevoflurane combined with propofol/remifentanil as the sedative/analgesic agents in four NF2 patients. ABI electrode arrays were placed in the awake phase with successful intraoperative hearing tests in three patients. There was one uncooperative patient whose awake hearing test needed to be aborted. In all cases, tumor resection and ABI were performed safely. Satisfactory electrode effectiveness was achieved in awake ABI placement. CONCLUSION: This case series suggests that awake craniotomy with an intraoperative hearing test for ABI placement is safe and well tolerated. Awake craniotomy is beneficial for improving the accuracy of ABI electrode placement and meanwhile reduces non-auditory side effects.

Perioperative massive cerebral stroke in thoracic patients: Report of three cases.

BACKGROUND: Perioperative stroke is a rare but devastating complication. The risk factors for massive cerebral stroke in surgical patients include older age, male sex, prior cerebrovascular disease, hypertension, renal failure, smoking, diabetes mellitus, and atrial fibrillation. CASE SUMMARY: We describe two cases of perioperative massive cerebral stroke following thoracic surgery and one case following bronchoscopy. Neurologic symptoms, including changes in mental status and hemiplegia, occurred within 10 h after surgery in the three patients. All three patients died after the surgery. CONCLUSION: Perioperative massive cerebral stroke may be more likely to occur in thoracic surgical patients if there are pre-existing factors including previous stroke, hypotension, and hypoxemia. Sufficient pain control after surgery and timely neurology consultation and management are helpful for the diagnosis and control of stroke in high-risk patients.

Changes in Neuroanesthesia Practice During the Early Stages of the COVID-19 Pandemic: Experiences From a Single Center in China.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by a novel coronavirus, is highly contagious. Global medical systems have been heavily impacted by the COVID-19 pandemic. Although the majority of patients with intracranial disease require time-sensitive surgery, how to conduct neurosurgery and prevent and control nosocomial infection during a pandemic is challenging. MATERIALS AND METHODS: We retrospectively reviewed the clinical data of patients undergoing neurosurgical and neurointerventional procedures at Beijing Tiantan Hospital, China during the early stages of the COVID-19 pandemic between January 21 and July 31, 2020. A 3-level system of COVID-19 risk was established based on medical conditions, epidemiologic, and symptom inquiry and the results of triage. A transitional unit was established for patients in whom COVID-19 had not been ruled out on admission to hospital. RESULTS: A total of 4025 patients underwent neurosurgery during the study period, including 768 emergent and 3257 nonemergent procedures. Of these patients, 3722 were low-risk for COVID-19, 303 were moderate-risk, and none were high-risk. In addition, 1419 patients underwent neurointerventional procedures, including 114 emergent and 1305 nonemergent interventions, of which 1339 were low-risk patients, 80 were moderate-risk and none were high-risk. A total of 895 patients (neurosurgical and neurointerventional) were admitted to the transitional unit. Forty-five patients were diagnosed with COVID-19 and transferred to the COVID-19 designated hospital. There were no cases of COVID-19 nosocomial infections among surgical patients or health care workers. CONCLUSION: On the basis of our single-center experience, developing a full screening protocol for COVID-19, establishing a risk level, and using a transitional unit for those with unknown COVID-19 status are effective measures to provide a safe environment for patients and health care workers.

Choice of ANaesthesia for EndoVAScular treatment of acute ischaemic stroke at posterior circulation (CANVAS II): protocol for an exploratory randomised controlled study.

INTRODUCTION: Observational and interventional studies indicate that the type of anaesthesia may be associated with the postprocedural neurological function in patients with anterior circulation acute ischaemic stroke undergoing endovascular treatment. Patients with acute posterior circulation ischaemic stroke may experience different physiological changes and result in severe neurological outcome. However, the effect of the type of anaesthesia on postprocedure neurological function remained unclear in this population. METHODS AND ANALYSIS: This is an exploratory randomised controlled trial that will be carried out at Beijing Tiantan Hospital, Capital Medical University. Patients with acute posterior circulation ischaemic stroke and deemed suitable for emergency endovascular recanalisation will be recruited in this trial. Eighty-four patients will be randomised to receive either general anaesthesia or conscious sedation with 1:1 allocation ratio. The primary endpoint is the 90-day modified Rankin Scale. ETHICS AND DISSEMINATION: The study has been reviewed by and approved by Ethics Committee of Beijing Tiantan Hospital of Capital Medical University (KY2017-074-02). If the results are positive, the study will indicate whether the type of anaesthesia affects neurological outcome after endovascular treatment of posterior stroke. The findings of the study will be published in peer-reviewed journals and presented at national or international conferences. TRIAL REGISTRATION NUMBER: NCT03317535.

Preserved individual differences in functional connectivity patterns under dexmedetomidine-induced sedation.

Functional connectivity patterns of the human brain show unique inherent or intrinsic characteristics at rest and when performing a task, similar to a fingerprint. However, whether this unique functional organization is preserved during sedation currently remains unknown. Here, we collected resting-state functional magnetic resonance imaging data from 20 subjects in each of three resting states: wakefulness, sedation, and recovery. We found that functional connectivity patterns could successfully identify individual subjects in any pair of the three resting states. In particular, identification analysis using functional connectivity patterns based on the frontoparietal network showed the highest success rates. Moreover, the overall individual difference in the frontoparietal-based functional connectivity patterns was much larger than that derived from other networks in each resting state. Collectively, our findings indicate that functional connectivity patterns within individual subjects are unique and relatively robust to brain state changes, regardless of dexmedetomidine-induced sedation.

Neuron-targeted caveolin-1 improves neuromuscular function and extends survival in SOD1G93A mice.

Interventions that preserve motor neurons or restore functional motor neuroplasticity may extend longevity in amyotrophic lateral sclerosis (ALS). Delivery of neurotrophins may potentially revive degenerating motor neurons, yet this approach is dependent on the proper subcellular localization of neurotrophin receptor (NTR) to plasmalemmal signaling microdomains, termed membrane/lipid rafts (MLRs). We previously showed that overexpression of synapsin-driven caveolin-1 (Cav-1) (SynCav1) increases MLR localization of NTR [e.g., receptor tyrosine kinase B (TrkB)], promotes hippocampal synaptic and neuroplasticity, and significantly improves learning and memory in aged mice. The present study crossed a SynCav1 transgene-positive (SynCav1+) mouse with the mutant human superoxide dismutase glycine to alanine point mutation at amino acid 93 (hSOD1G93A) mouse model of ALS. When compared with hSOD1G93A, hSOD1G93A/SynCav1+ mice exhibited greater body weight and longer survival as well as better motor function. Microscopic analyses of hSOD1G93A/SynCav1+ spinal cords revealed preserved spinal cord α-motor neurons and preserved mitochondrial morphology. Moreover, hSOD1G93A/SynCav1+ spinal cords contained more MLRs (cholera toxin subunit B positive) and MLR-associated TrkB and Cav-1 protein expression. These findings demonstrate that SynCav1 delays disease progression in a mouse model of ALS, potentially by preserving or restoring NTR expression and localization to MLRs.-Sawada, A., Wang, S., Jian, M., Leem, J., Wackerbarth, J., Egawa, J., Schilling, J. M., Platoshyn, O., Zemljic-Harpf, A., Roth, D. M., Patel, H. H., Patel, P. M., Marsala, M., Head, B. P. Neuron-targeted caveolin-1 improves neuromuscular function and extends survival in SOD1G93A mice.