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Laryngoscopy for tracheal intubation has been developed for many decades. Among various conventional laryngoscopes, videolaryngoscopes (VLs) have been applied in different patient populations, including difficult airways. The safety and effectiveness of VLs have been repeatedly studied in both normal and difficult airways. The superiority of VLs then has been observed and is advocated as the standard of care. In contrast to laryngoscopy, the development of video-assisted intubating stylet (VS, also named as styletubation) was noticed two decades ago. Since then, sporadic clinical experiences of use have appeared in the literature. In this review article, we presented our vast use experiences of the styletubation (more than 55,000 patients since 2016). We found this technique to be swift (the time to intubate from 3 s to 10 s), smooth (first-attempt success rate: 100%), safe (no airway complications), and easy (high subjective satisfaction and fast learning curve for the novice trainees) in both normal and difficult airway scenarios. We, therefore, propose that the styletubation technique can be feasibly applied as universal routine use for tracheal intubation. [ABSTRACT FROM AUTHOR]

Spin- and angle-resolved photoemission spectroscopy ("spin-ARPES") is a powerful technique for probing the spin degree-of-freedom in materials with nontrivial topology, magnetism, and strong correlations. Spin-ARPES faces severe experimental challenges compared to conventional ARPES attributed to the dramatically lower efficiency of its detection mechanism, making it crucial for instrumentation developments that improve the overall performance of the technique. In this paper, we demonstrate the functionality of our spin-ARPES setup based on time-of-flight spectroscopy and introduce our recent development of an electrostatic deflector mode to map out spin-resolved band structures without sample rotation. We demonstrate the functionality by presenting the spin-resolved spectra of the topological insulator Bi2Te3 and describe in detail the spectrum calibrations based on numerical simulations. By implementing the deflector mode, we minimize the need for sample rotation during measurements, hence improving the overall efficiency of experiments on small or inhomogeneous samples. [ABSTRACT FROM AUTHOR]

Background: In this study, we compare the clinical characteristics, intraoperative management, and postoperative outcomes of patients with acute type A aortic dissection (ATAAD) between two academic medical hospitals in the United States and China.Methods: From January 2011 to December 2017, 641 and 150 patients from Nanjing Drum Tower Hospital (NDTH) and Massachusetts General Hospital (MGH) were enrolled. Patient demographics, clinical features, surgical techniques, and postoperative outcomes were compared.Results: The annual number of patients presenting with ATAAD at MGH remained relatively stable, while the number at NDTH increased significantly over the study period. The average age was 51 years at NDTH and 61 years at MGH (P < .001). The percentage of patients with known hypertension at the two centers was similar. The time interval from onset of symptoms to diagnosis was significantly longer at NDTH than MGH (11 vs 3.5 hours; P < .001). Associated complications at presentation were more common at NDTH than MGH. More than 90% of patients (91% NDTH and 92% MGH) underwent surgery. The postoperative stroke rate was higher at MGH (12% vs 4%; P < .001); however, the 30-day mortality rate was lower (7% vs 16%; P = .006).Conclusions: There was a significant increase in the number of ATAAD at NDTH during the study period while the number at MGH remained stable. Hypertension was a common major risk factor; however, the onset of ATAAD at NDTH was nearly one decade earlier than MGH. Chinese patients tended to have more complicated preoperative pathophysiology at presentation and underwent more extensive surgical repair. [ABSTRACT FROM AUTHOR]

Background: Migration of physicians has been a cause for global concern. In China, reforms of the higher education and healthcare systems have led to a shortage of postgraduate training positions relative to the number of medical graduates. Medical graduates opt for non-clinical roles or move abroad to pursue further training and practice opportunities. The impact of this physician migration is not known. This study quantifies where Chinese migrant physicians to the U.S. were educated, where they went to practice, and how these trends have changed over time. Methods: We combined data on physician characteristics from the 2008 and 2017 American Medical Association Physician Masterfiles with demographic information from the Educational Commission for Foreign Medical Graduates. Using a repeated cross-sectional approach, we reviewed the available data, including citizenship at entry to medical school, medical school attended, practice specialty, and practice location. Results: The number of Chinese-educated physicians (CEPs) to the United States (US) has increased over the past 10 years, from 3,878 in 2008 to 5,355 in 2017 (+38.1%). The majority held Chinese citizenship at entry to medical school (98.4% vs 97.1%) with the remainder being citizens of other East Asian nations. Of the Chinese citizens identified in 2008, 913 (19.3%) attended medical school outside of China; in 2017, 376 (6.7%) attended medical school outside of China, representing a decrease of 58.8%. Overall, in 2017, four Chinese medical schools provided 32.1% of all Chinese-educated physicians in the US. Over 50% of the CEPs were practicing in Internal Medicine, Anatomic/ Clinical Pathology, Anesthesiology, Family Medicine or Neurology. Compared with all IMGs, CEPs are more likely to be Anatomic/ Clinical Pathologists and Anesthesiologists. CEPs were concentrated in several states, including New York, California and Massachusetts. In 2017, a lower proportion of CEPs in the US healthcare workforce were in residency training, compared to 2008 (13.2% vs 22.8%). Conclusions: Unlike trends from some other South Asian countries, the number of CEPs in the US has increased over the past 10 years. Migration trends may vary depending on citizenship and country of medical school training. The majority of Chinese-educated graduates come to the US from relatively few medical schools. Fewer CEPs currently in residency training might indicate lower success rates in securing GME training in the US. [ABSTRACT FROM AUTHOR]

Background: Acute type A aortic dissection (aTAAD) is a lethal disease and age is an important risk factor for outcomes. This retrospective study was to analyze the impact of age stratification in aTAAD, and to provide clues for surgeons when they make choices of therapy strategies.Methods: From January 2011 to December 2019, 1092 aTAAD patients from Nanjing Drum Tower Hospital received surgical therapy. Patients were divided into 7 groups according to every ten-year interval (20-80 s). The differences between the groups were analyzed in terms of the baseline preoperative conditions, surgical methods and postoperative outcomes of patients of different age groups. During a median follow-up term of 17 months, the survival rates were compared among 7 groups through Kaplan-Meier analysis.Results: The median age was 52.0 years old in whole cohort. The multiple comorbidities were more common in old age groups (60 s, 70 s, 80 s), while the 20 s group patients had the highest proportion of Marfan syndrome (28.1%). Preoperative hypotension was highest in 80 s (16.7%, P = 0.038). Young age groups (20-60 s) had a higher rate of root replacement and total arch replacement, which led to a longer duration of operation and hypothermic circulation arrest. The overall mortality was 14.1%, the tendency of mortality was increased with age except 20 s group (33.3% in 80 s, P = 0.016). The postoperative morbidity of gastrointestinal bleeding and bowel ischemia were 16.7% and 11.1% in 80 s group.Conclusions: Age is a major impact factor for aTAAD surgery. Old patients presented more comorbidities before surgery, the mortality and complications rate were significantly higher even with less invasive and conservative surgical therapy. But the favorable long-term survival indicated that the simple or less extensive arch repair is the preferred surgery for patients over 70 years old. [ABSTRACT FROM AUTHOR]

• Ketamine is an anesthetic drug with dissociative properties. • Ketamine induces highly structured oscillations that may be used to monitor drug-induced altered arousal. • Surface electroencephalogram oscillations are unlikely to underly ketamine-induced dissociation. Ketamine is an anesthetic drug associated with dissociation. Decreased electroencephalogram alpha (8–13 Hz) and low-beta (13–20 Hz) oscillation power have been associated with ketamine-induced dissociation. We aimed to characterize surface electroencephalogram signatures that may serve as biomarkers for dissociation. We analyzed data from a single-site, open-label, high-density surface electroencephalogram study of ketamine anesthesia (2 mg/kg, n = 15). We assessed dissociation longitudinally using the Clinician Administered Dissociation States Scale (CADSS) and administered midazolam to attenuate dissociation and enable causal inference. We analyzed electroencephalogram power and global coherence with multitaper spectral methods. Mixed effects models were used to assess whether power and global coherence signatures of ketamine could be developed into dissociation-specific biomarkers. Compared to baseline, ketamine unresponsiveness was associated with increased frontal power between 0.5 to 9.3 Hz, 12.2 to 16.6 Hz, and 24.4 to 50 Hz. As subjects transitioned into a responsive but dissociated state (mean CADSS ± SD, 22.1 ± 17), there was a decrease in power between 0.5 to 10.3 Hz and 11.7 to 50 Hz. Midazolam reduced dissociation scores (14.3 ± 11.6), decreased power between 4.4 to 11.7 Hz and increased power between 14.2 to 50 Hz. Our mixed-effects model demonstrated a quadratic relationship between time and CADSS scores. When models (frontal power, occipital power, global coherence) were reanalyzed with midazolam and electroencephalogram features as covariates, only midazolam was retained. Ketamine is associated with structured electroencephalogram power and global coherence signatures that may enable principled anesthetic state but not dissociation monitoring. A neurophysiological biomarker for dissociation may lead to a better understanding of neuropsychiatric disorders. [ABSTRACT FROM AUTHOR]

Hospitalized older patients who undergo elective cardiac surgery with cardiopulmonary bypass are prone to postoperative delirium. Self‐reported shorter sleep and longer sleep have been associated with impaired cognition. Few data exist to guide us on whether shorter or longer sleep is associated with postoperative delirium in this hospitalized cohort. This was a prospective, single‐site, observational study of hospitalized patients (>60 years) scheduled to undergo elective major cardiac surgery with cardiopulmonary bypass (n = 16). We collected and analysed overnight polysomnography data using the Somté PSG device and assessed for delirium twice a day until postoperative day 3 using the long version of the confusion assessment method and a structured chart review. We also assessed subjective sleep quality using the Pittsburg Sleep Quality Index. The delirium median preoperative hospital stay of 9 [Q1, Q3: 7, 11] days was similar to the non‐delirium preoperative hospital stay of 7 [4, 9] days (p =.154). The incidence of delirium was 45.5% (10/22) in the entire study cohort and 50% (8/16) in the final cohort with clean polysomnography data. The preoperative delirium median total sleep time of 323.8 [Q1, Q3: 280.3, 382.1] min was longer than the non‐delirium median total sleep time of 254.3 [210.9, 278.1] min (p =.046). This was accounted for by a longer delirium median non‐rapid eye movement (REM) stage 2 sleep duration of 282.3 [229.8, 328.8] min compared to the non‐delirium median non‐REM stage 2 sleep duration of 202.5 [174.4, 208.9] min (p =.012). Markov chain modelling confirmed these findings. There were no differences in measures of sleep quality assessed by the Pittsburg Sleep Quality Index. Polysomnography measures of sleep obtained the night preceding surgery in hospitalized older patients scheduled for elective major cardiac surgery with cardiopulmonary bypass are suggestive of an association between longer sleep duration and postoperative delirium. [ABSTRACT FROM AUTHOR]

Background: Ketamine is a dissociative anesthetic with analgesic properties. Ketamine's analgesic properties have been suggested to result from its dissociative properties. To the authors' knowledge, this postulate is unsubstantiated. The authors hypothesize that the dissociative and analgesic properties of ketamine are independent.Methods: The authors conducted a single-site, open-label study of ketamine anesthesia (2 mg/kg) in 15 healthy subjects. Midazolam was administered at a prespecified time point to attenuate dissociation. The authors longitudinally assessed precalibrated cuff pain intensity and quality using Patient-Reported Outcomes Measurement Information System questionnaires, and dissociation, using the Clinician Administered Dissociative States Scale. Mixed effects models were used to assess whether dissociation accounted for the effect of ketamine on pain intensity and quality.Results: The dissociation model demonstrated an inverted U-shaped quadratic relationship between time and dissociation scores. Additive to this effect, midazolam reduced the dissociation adjusted means by 10.3 points (95% CI, 3.4 to 17.1; P = 0.005). The pain intensity model also demonstrated a U-shaped quadratic relationship between time and pain intensity. When the pain intensity model was reanalyzed with dissociation scores as an additional covariate, the dissociation term was not retained in the model, and the other effects were preserved in direction and strength. This result was conserved for nociceptive and neuropathic pain quality.Conclusions: Ketamine's analgesic properties are not exclusively caused by dissociation. Thus, ketamine may be used as a probe to advance our knowledge of dissociation independent neural circuits that encode pain.Editor’s Perspective: [ABSTRACT FROM AUTHOR]

Background: Intraoperative burst-suppression is associated with postoperative delirium. Whether this association is causal remains unclear. Therefore, the authors investigated whether burst-suppression during cardiopulmonary bypass (CPB) mediates the effects of known delirium risk factors on postoperative delirium.Methods: This was a retrospective cohort observational substudy of the Minimizing ICU [intensive care unit] Neurological Dysfunction with Dexmedetomidine-induced Sleep (MINDDS) trial. The authors analyzed data from patients more than 60 yr old undergoing cardiac surgery (n = 159). Univariate and multivariable regression analyses were performed to assess for associations and enable causal inference. Delirium risk factors were evaluated using the abbreviated Montreal Cognitive Assessment and Patient-Reported Outcomes Measurement Information System questionnaires for applied cognition, physical function, global health, sleep, and pain. The authors also analyzed electroencephalogram data (n = 141).Results: The incidence of delirium in patients with CPB burst-suppression was 25% (15 of 60) compared with 6% (5 of 81) in patients without CPB burst-suppression. In univariate analyses, age (odds ratio, 1.08 [95% CI, 1.03 to 1.14]; P = 0.002), lowest CPB temperature (odds ratio, 0.79 [0.66 to 0.94]; P = 0.010), alpha power (odds ratio, 0.65 [0.54 to 0.80]; P < 0.001), and physical function (odds ratio, 0.95 [0.91 to 0.98]; P = 0.007) were associated with CPB burst-suppression. In separate univariate analyses, age (odds ratio, 1.09 [1.02 to 1.16]; P = 0.009), abbreviated Montreal Cognitive Assessment (odds ratio, 0.80 [0.66 to 0.97]; P = 0.024), alpha power (odds ratio, 0.75 [0.59 to 0.96]; P = 0.025), and CPB burst-suppression (odds ratio, 3.79 [1.5 to 9.6]; P = 0.005) were associated with delirium. However, only physical function (odds ratio, 0.96 [0.91 to 0.99]; P = 0.044), lowest CPB temperature (odds ratio, 0.73 [0.58 to 0.88]; P = 0.003), and electroencephalogram alpha power (odds ratio, 0.61 [0.47 to 0.76]; P < 0.001) were retained as predictors in the burst-suppression multivariable model. Burst-suppression (odds ratio, 4.1 [1.5 to 13.7]; P = 0.012) and age (odds ratio, 1.07 [0.99 to 1.15]; P = 0.090) were retained as predictors in the delirium multivariable model. Delirium was associated with decreased electroencephalogram power from 6.8 to 24.4 Hertz.Conclusions: The inference from the present study is that CPB burst-suppression mediates the effects of physical function, lowest CPB temperature, and electroencephalogram alpha power on delirium. [ABSTRACT FROM AUTHOR]

Highlights • Intraoperative electroencephalogram burst-suppression is associated with post-operative delirium. • Decreased alpha and beta power was evident in the EEG prior to the occurrence of burst-suppression. • Decreased EEG alpha and beta power predicted the later incidence and duration of burst-suppression. Abstract Objective Electroencephalogram burst-suppression during general anesthesia is associated with post-operative delirium (POD). Whether burst-suppression causes POD or merely reflects susceptibility to POD is unclear. We hypothesized decreased intraoperative alpha (8–12 Hz) and beta (13–33 Hz) power prior to the occurrence of burst-suppression in susceptible patients. Methods We analyzed intraoperative electroencephalogram data of cardiac surgical patients undergoing cardiopulmonary bypass (CPB). We detected the incidence and duration of CPB burst-suppression with an automated burst-suppression detection algorithm. We analyzed EEG data with multitaper spectral estimation methods. We assessed associations between patient characteristics and burst-suppression using Binomial and Zero-inflated Poisson Regression Models. Results We found significantly decreased alpha and beta power (7.8–22.95 Hz) in the CPB burst-suppression cohort. The odds ratio for the association between point estimates for alpha and beta power (7.8–22.95 Hz) and the incidence of burst-suppression was 0.88 (95% CI: 0.79–0.98). The incidence rate ratio for the association between point estimates for power between the alpha and beta range and the duration of burst-suppression was 0.89 (95% CI: 0.84–0.93). Conclusion Decreased intra-operative power within the alpha and beta range was associated with susceptibility to burst-suppression during CPB. Significance This dynamic may be used to develop principled neurophysiological-based approaches to aid the preemptive identification and targeted care of POD vulnerable patients. [ABSTRACT FROM AUTHOR]

Understanding anesthetic mechanisms with the goal of producing anesthetic states with limited systemic side effects is a major objective of neuroscience research in anesthesiology. Coherent frontal alpha oscillations have been postulated as a mechanism of sevoflurane general anesthesia. This postulate remains unproven. Therefore, we performed a single-site, randomized, cross-over, high-density electroencephalogram study of sevoflurane and sevoflurane-plus-ketamine general anesthesia in 12 healthy subjects. Data were analyzed with multitaper spectral, global coherence, cross-frequency coupling, and phase-dependent methods. Our results suggest that coherent alpha oscillations are not fundamental for maintaining sevoflurane general anesthesia. Taken together, our results suggest that subanesthetic and general anesthetic sevoflurane brain states emerge from impaired information processing instantiated by a delta-higher frequency phase-amplitude coupling syntax. These results provide fundamental new insights into the neural circuit mechanisms of sevoflurane anesthesia and suggest that anesthetic states may be produced by extracranial perturbations that cause delta-higher frequency phase-amplitude interactions. Chamadia et al. show that a delta-higher frequency phase-amplitude coupling syntax, rather than coherent frontal alpha oscillations, is fundamental to sevoflurane anesthesia. Their conclusion is based on analyzing different EEG measures across different anesthetic states. [ABSTRACT FROM AUTHOR]