渡瀬 博子

BACKGROUND: The video laryngoscope (VL) has been widely used for intubation in the emergency department (ED). However, their effectiveness remains controversial, particularly among airway management performed by residents in the ED. METHODS: We aimed to examine whether the use of VL, compared to a direct laryngoscope (DL), was associated with higher first-attempt intubation success among intubations performed by residents in the ED. This is a secondary analysis of the data from a prospective, observational, multicentre study of 15 Japanese EDs from April 2012 through March 2020. We included all adult patients who underwent intubation with VL or DL by residents (postgraduate years ≤5) in the ED. The outcome measures were first-pass success and intubation-related adverse events (overall, major, and minor adverse events). To determine the association of VL use with each of the outcomes, we constructed logistic regression models with generalized estimating equations to account for patients clustering within the ED, adjusting for patient demographics, primary indications, intubation difficulty, and intubation methods. RESULTS: Of 5,261 eligible patients who underwent an initial intubation attempt by residents, 1,858 (35%) patients were attempted with VL. Intubations performed with VL had a non-significantly higher first-pass success rate than those with DL (77% vs. 64%; unadjusted odds ratio (OR)=1.20; 95% CI=0.87-1.65; P=0.27). This association was significant after adjustment for potential confounders (adjusted OR, 1.33; 95% CI, 1.06-1.67; P=0.01). As for adverse events, the use of VL was associated with a lower rate of any (adjusted OR=0.67; 95% CI=0.51-0.86; P=0.002) and minor (adjusted OR=0.69; 95% CI=0.55-0.87; P=0.002) adverse events. CONCLUSION: The use of VL was associated with a higher first-attempt success rate and a lower rate of any adverse events compared to that with DL among intubations performed by residents in the EDs.

BACKGROUND AND PURPOSE: Atherosclerosis is a very complex process influenced by various systemic and local factors. Therefore, in patients with bilateral carotid plaques (BCPs), there may be differences in carotid plaque vulnerability between the sides. We aimed to investigate the differences in BCP characteristics in patients with BCPs using magnetic resonance vessel wall imaging (MR-VWI). METHODS: Participants with BCPs were selected for subanalysis from a multicentre study of Chinese Atherosclerosis Risk Evaluation II. We measured carotid plaque burden, identified each plaque component and measured their volume or area bilaterally on MR-VWI. Paired comparisons of the burden and components of BCPs were performed. RESULTS: In all, 540 patients with BCPs were eligible for analysis. Compared with the right carotid artery (CA), larger mean lumen area (p<0.001), larger mean wall area (p=0.025), larger mean total vessel area (p<0.001) and smaller normalised wall index (p=0.006) were found in the left CA. Regarding plaque components, only the prevalence of lipid-rich necrotic core (LRNC) in the left CA was higher (p=0.026). For patients with a vulnerable plaque component coexisting on both sides, only the intraplaque haemorrhage (IPH) volume (p=0.011) was significantly greater in the left CA than in the right CA. CONCLUSIONS: There were asymmetries in plaque growth and evolution between BCPs. The left carotid plaques were more likely to have larger plaque burden, higher prevalence of LRNC and greater IPH volume, which may contribute to the lateralisation of ischaemic stroke in the cerebral hemispheres.

Recent studies report that the rate of recurrent stroke is highest in the stages immediately following cerebral infarction and decreases over time in patients with atherosclerotic carotid stenosis. The purpose of this study was to identify temporal differences in early stage carotid plaque components from acute cerebrovascular ischemic events using carotid MRI. Carotid plaque images were obtained on 3 T MRI from 128 patients enrolled in MR-CAS. Among the 128 subjects, 53 were symptomatic and 75 asymptomatic. The symptomatic patients were classified into three groups based on interval from onset of symptoms to the date of the carotid MRI (Group <14 days; 15-30 days; and > 30 days). The volume of each plaque component was identified and quantified from MR images. The presence of juxtaluminal loose matrix/inflammation (LM/I) was identified as a possible indicator of inflammation on the luminal side. Plaque components were compared between groups using the Wilcoxon rank-sum or the Chi-square test. Patient characteristics and carotid plaque morphology were similar among all four groups. The median volume of LM/I in Group >30 days was significantly lower than in other groups (0 mm3 vs 12.3 mm3 and 18.1 mm3; p = 0.003). In addition, the prevalence of juxtaluminal LM/I decreased over time (ptrend = 0.002). There were no statistically significant differences in other plaque components between the symptomatic groups. The volume of LM/I was significantly smaller in Group >30 days and prevalence of juxtaluminal LM/I in the atherosclerotic carotid plaque was high in the early stages after events. This suggests that carotid plaques undergo rapid evolution after an acute cerebrovascular ischemic event.

BACKGROUND: Airway obstruction is a relatively rare but critical condition that requires urgent intervention in the emergency department (ED). The present study aimed to investigate the association of airway obstruction with first-pass success and intubation-related adverse events in the ED. METHODS: We analyzed data from two prospective multicenter observational studies of ED airway management. We included adults (aged ≥18 years) who underwent tracheal intubation for non-trauma indications from 2012 through 2021 (113-month period). Outcome measures were first-pass success and intubation-related adverse events. We constructed a multivariable logistic regression model adjusting for age, sex, modified LEMON score (without airway obstruction), intubation methods, intubation devices, bougie use, intubator's specialty, and ED visit year with accounting for patients clustering within the ED. RESULTS: Of 7,349 eligible patients, 272 (4%) underwent tracheal intubation for airway obstruction. Overall, 74% of patients had first-pass success and 16% had intubation-related adverse events. The airway obstruction group had a lower first-pass success rate (63% vs. 74%; unadjusted odds ratio [OR], 0.63; 95% CI, 0.49-0.80), compared to the non-airway obstruction group. This association remained significant in the multivariable analysis (adjusted OR 0.60, 95%CI 0.46-0.80). The airway obstruction group also had a significantly higher risk of adverse events (28% vs. 16%; unadjusted OR, 1.93; 95% CI, 1.48-2.56, adjusted OR, 1.70; 95% CI, 1.27-2.29). In the sensitivity analysis using multiple imputation, the results remained consistent with the main results: the airway obstruction group had a significantly lower first-pass success rate (adjusted OR, 0.60; 95% CI, 0.48-0.76). CONCLUSION: Based on these multicenter prospective data, airway obstruction was associated with a significantly lower first-pass success rate and a higher intubation-related adverse event rate in the ED.

[This corrects the article DOI: 10.3389/fmed.2023.1199750.].

This cohort study examines the association between the number of physician postgraduate years and intubation outcomes among patients undergoing airway management in the emergency department.

STUDY OBJECTIVES: Studies have shown that multiple intubation attempts are associated with a higher risk of intubation-related adverse events. However, little is known about the relationship in children in the emergency department (ED). METHODS: This is an analysis of the data from 2 prospective, observational, multicenter registries of emergency airway management. The data were collected from consecutive patients who underwent emergency airway management in 19 EDs across Japan from March 2010 to November 2017. We included children 18 years or younger who underwent tracheal intubation in the ED. The primary exposure was the number of intubation attempts (1 vs ≥2). The primary outcome was an adverse event during or immediately after the intubation. RESULTS: A total of 439 children were eligible for the analysis. Of 279 children with first-pass success, 24 children (9%) had an adverse event. By contrast, of 160 children with ≥2 intubation attempts, 50 children patients (31%) had an adverse event. In the unadjusted model, multiple intubation attempts were significantly associated with a higher rate of adverse events (unadjusted odds ratio, 4.83; 95% confidence interval, 2.57-9.06; P < 0.001). This association remained significant after adjusting for 7 potential confounders and patient clustering within the hospital (adjusted odds ratio, 4.49; 95% confidence interval, 2.36-8.53; P < 0.001). Similar associations were found across different age groups and among children without cardiac arrest (all, P < 0.05). CONCLUSIONS: In this analysis of large prospective multicenter data, multiple intubation attempts were associated with a significantly higher rate of intubation-related adverse events in children in the ED.

BACKGROUND AND PURPOSE: Two-dimensional high-resolution multicontrast magnetic resonance imaging (2D-MC MRI) is currently the most reliable and reproducible noninvasive carotid vessel wall imaging technique. However, the long scan time required for 2D-MC MRI restricts its practical clinical application. Alternatively, 3-dimensional motion-sensitized driven-equilibrium prepared rapid gradient echo (3D-MERGE) vessel wall MRI can provide high isotropic resolution with extensive coverage in two minutes. In this study, we sought to prove that 3D-MERGE alone can serve as a screening tool to identify advanced carotid lesions. METHODS: Two hundred twenty-seven subjects suspected of recent ischemic stroke or transient ischemic attack were imaged using 2D-MC MRI with an imaging time of 30 minutes, then with 3D-MERGE with an imaging time of 2 minutes, on 3T-MRI scanners. Two experienced reviewers interpreted plaque components using 2D-MC MRI as the reference standard and categorized plaques using a modified American Heart Association lesion classification for MRI. Plaques of American Heart Association type IV and above were classified as advanced. Arteries of American Heart Association types I to II and III were categorized as normal or with early lesions, respectively. One radiologist independently reviewed only 3D-MERGE and labeled the plaques as advanced if they had a wall thickness of >2 mm with high or low signal intensity compared with the adjacent sternocleidomastoid muscle. Sensitivity, specificity, and accuracy for 3D-MERGE were calculated. RESULTS: Four hundred forty-nine arteries from 227 participants (mean age 61.2 years old, 64% male) were included in the analysis. Sensitivity, specificity, and accuracy for identification of advanced lesions on 3D-MERGE were 95.0% (95% CI, 91.8-97.2), 86.9% (95% CI, 81.4-92.0), 93.8% (95% CI, 91.1-95.8), respectively. CONCLUSIONS: 3D-MERGE can accurately identify advanced carotid atherosclerotic plaques in patients suspected of stroke or transient ischemic attack. It has a more extensive coverage and higher sensitivity and specificity for advanced plaque detection with a much shorter acquisition time than 2D-MC MRI. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02017756.

BACKGROUND: While the older population accounts for an increasing proportion of emergency department (ED), little is known about intubation-related adverse events in this high-risk population. We sought to determine whether advanced age is associated with a higher risk of intubation-related adverse events in the ED. METHODS: This is an analysis of data from a prospective, 15-centre, observational study-the second Japanese Emergency Airway Network (JEAN-2) study. The current analysis included adult (aged ≥18 years) patients who underwent intubation in the ED between 2012 and 2018. The primary exposure was age (18-39, 40-64, 65-74, 75-84 and ≥85 years). The primary outcome was overall intubation-related adverse events during or immediately after an intubation. Adverse events were further categorised into major (hypotension, hypoxaemia, oesophageal intubation, cardiac arrest, dysrhythmia and death) and minor (endobronchial intubation, oesophageal intubation with early recognition, dental/lip trauma, airway trauma and regurgitation) adverse events. We constructed multivariable logistic regression models adjusting for seven potential confounders with generalised estimating equations that account for patients clustering within the ED. RESULTS: Among 9714 patients eligible for the analysis, 15% were aged ≥85 years, and 16% had adverse events. In the unadjusted models, advanced age was not significantly associated with the risk of overall adverse events. In the adjusted models, the association was significant (adjusted OR 1.41 in age ≥85 years (95% CI, 1.09 to 1.81) compared with age 18-39 years). Specifically, older patients had a significantly higher risk of major adverse events (adjusted OR in age ≥85 years 2.65 (95% CI, 1.78 to 3.94)), which was driven by the association of advanced age with an increased risk of hypotension (adjusted OR in ≥85 years, 5.69 (95% CI, 3.13 to 10.37)). By contrast, advanced age was not associated with minor adverse events. CONCLUSION: Based on the data from a prospective multicentre study, advanced age was associated with higher risks of major adverse events.

PURPOSE: To develop and evaluate a domain adaptive and fully automated review workflow (lesion assessment through tracklet evaluation, LATTE) for assessment of atherosclerotic disease in 3D carotid MR vessel wall imaging (MR VWI). METHODS: VWI of 279 subjects with carotid atherosclerosis were used to develop LATTE, mainly convolutional neural network (CNN)-based domain adaptive lesion classification after image quality assessment and artery of interest localization. Heterogeneity in test sets from various sites usually causes inferior CNN performance. With our novel unsupervised domain adaptation (DA), LATTE was designed to accurately classify arteries into normal arteries and early and advanced lesions without additional annotations on new datasets. VWI of 271 subjects from four datasets (eight sites) with slightly different imaging parameters/signal patterns were collected to assess the effectiveness of DA of LATTE using the area under the receiver operating characteristic curve (AUC) on all lesions and advanced lesions before and after DA. RESULTS: LATTE had good performance with advanced/all lesion classification, with the AUC of >0.88/0.83, significant improvements from >0.82/0.80 if without DA. CONCLUSIONS: LATTE can locate target arteries and distinguish carotid atherosclerotic lesions with consistently improved performance with DA on new datasets. It may be useful for carotid atherosclerosis detection and assessment on various clinical sites.

Background An artificial intelligence vessel segmentation tool, Fully Automated and Robust Analysis Technique for Popliteal Artery Evaluation (FRAPPE), was used to analyze a large databank of popliteal arteries imaged through the OAI (Osteoarthritis Initiative) to study the impact of atherosclerosis risk factors on vessel dimensions and characterize remodeling patterns. Methods and Results Magnetic resonance images from 4668 subjects contributing 9189 popliteal arteries were analyzed using FRAPPE. Age ranged from 45 to 79 years (median, 61), and 58% were women. Mean lumen diameter, mean outer wall diameter, and mean wall thickness (MWT) were measured per artery. Their median values were 5.8 mm (interquartile range, 5.2-6.5 mm), 7.3 mm (interquartile range, 6.7-8.1 mm), and 0.78 mm (interquartile range, 0.73-0.84 mm) respectively. MWT was associated with multiple cardiovascular risk factors, with age (4.2% increase in MWT per 10-year increase in age; 95% CI, 3.9%-4.5%) and sex (8.6% higher MWT in men than women; 95% CI, 7.7%-9.3%) being predominant. On average, lumen and outer wall diameters increased with increasing MWT until the thickness was 0.92 mm for men and 0.84 mm for women. After this point, lumen diameter decreased steadily, more rapidly in men than women (-7.9% versus -6.1% per 25% increase in MWT; P<0.001), with little change in outer wall diameter. Conclusions FRAPPE has enabled the analysis of the large OAI knee magnetic resonance imaging data set, successfully showing that popliteal atherosclerosis is predominantly associated with age and sex. The average vessel remodeling pattern consisted of an early phase of compensatory enlargement, followed by a negative remodeling, which is more pronounced in men.

OBJECTIVE: To evaluate the association of CT/CT angiography (CTA) findings and clinical characteristics with subsequent vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH). METHODS-: Consecutive presentation CTA head exams in patients with aSAH between January 2005 and June 2015 were retrospectively evaluated for intracranial arterial calcification, undulation and non-calcified stenosis. Additional variables including modified Fisher Scale (mFS), Glasgow Coma Scale (GCS) and neurological exam status were reviewed. Associations of CTA findings with the incidence of angiographic vasospasm were assessed with multivariate logistic regression models using the least absolute shrinkage and selection operator machine-learning algorithm. Model performance was summarized using c-index with bootstrap optimism-adjustment. RESULTS: Intracranial arterial calcification, seen in 51.7% of 195 total patients, was protective against vasospasm (OR-0.6; 95% CI-0.52-0.67; p = 0.009), while arterial undulation (24%) was associated with subsequent vasospasm (OR-2.6; 95% CI-1.3-5.1; p = 0.007). Non-calcified intracranial arterial stenosis (5%) was associated with subsequent vasospasm, (OR-4.7; 95% CI-1.0-22.8; p = 0.054). Least absolute shrinkage and selection operator selected all three CTA findings as predictors in a multivariate model for vasospasm in addition to clinical factors, which demonstrated superior predictive performance (c-index-0.74; 95% CI-0.69-0.82) compared to a model based on mFS and clinical factors only (c-index-0.66; 95% CI-0.57-0.75; p = 0.010 for the difference). CONCLUSION: Presentation CTA findings combined with clinical factors may better predict the development of vasospasm in patients with aSAH compared to current prognostic models alone. ADVANCES IN KNOWLEDGE: The combination of initial CT/CTA and clinical findings better predict development of vasospasm after aSAH. This can lead to better markers for use in future clinical trials to develop vasospasm preventative treatments and potentially provide better targets for early aggressive treatment.

BACKGROUND: There is still room for improvement in the modified LEMON (look, evaluate, Mallampati, obstruction, neck mobility) criteria for difficult airway prediction and no prediction tool for first-pass success in the emergency department (ED). OBJECTIVE: We applied modern machine learning approaches to predict difficult airways and first-pass success. METHODS: In a multicenter prospective study that enrolled consecutive patients who underwent tracheal intubation in 13 EDs, we developed 7 machine learning models (eg, random forest model) using routinely collected data (eg, demographics, initial airway assessment). The outcomes were difficult airway and first-pass success. Model performance was evaluated using c-statistics, calibration slopes, and association measures (eg, sensitivity) in the test set (randomly selected 20% of the data). Their performance was compared with the modified LEMON criteria for difficult airway success and a logistic regression model for first-pass success. RESULTS: Of 10,741 patients who underwent intubation, 543 patients (5.1%) had a difficult airway, and 7690 patients (71.6%) had first-pass success. In predicting a difficult airway, machine learning models-except for k-point nearest neighbor and multilayer perceptron-had higher discrimination ability than the modified LEMON criteria (all, P≤.001). For example, the ensemble method had the highest c-statistic (0.74 vs 0.62 with the modified LEMON criteria; P<.001). Machine learning models-except k-point nearest neighbor and random forest models-had higher discrimination ability for first-pass success. In particular, the ensemble model had the highest c-statistic (0.81 vs 0.76 with the reference regression; P<.001). CONCLUSIONS: Machine learning models demonstrated greater ability for predicting difficult airway and first-pass success in the ED.

BACKGROUND AND PURPOSE: While extracranial carotid artery stenosis is more common among Caucasians and intracranial artery stenosis is more common among Asians, the differences in atherosclerotic plaque characteristics have not yet been extensively examined. We sought to investigate plaque location and characteristics within extracranial carotid and intracranial arteries in symptomatic Caucasians and Chinese using vessel wall MRI. METHODS: Subjects with recent anterior circulation ischaemic stroke were recruited and imaged at two sites in the USA and China using similar protocols. Both extracranial carotid and intracranial arteries were reviewed to determine plaque location and characteristics. RESULTS: The prevalence of extracranial carotid plaque in Caucasians and Chinese was 73.1% and 49.1%, respectively (p=0.055). Prevalence of intracranial plaque was 38.5% and 69.1% in Caucasians and Chinese, respectively (p=0.02). Furthermore, 42% of Caucasians and 16% of Chinese had high-risk plaque (HRP) features (intraplaque haemorrhage, luminal surface disruption) in the extracranial carotid artery (p=0.03). The prevalence of HRP features in intracranial arteries was not significantly different between the two cohorts (4% vs 11%; p=0.42). CONCLUSIONS: Differences in the location and characteristics of cerebrovascular atherosclerosis were identified by vessel wall MRI in US Caucasian and Chinese subjects with recent anterior circulation ischaemic stroke. Extracranial carotid plaques with HRP features were more common in Caucasians. Intracranial plaques were more common in Chinese subjects, but no significant difference between the two cohorts in intracranial HRP prevalence was found. Larger studies using vessel wall imaging to investigate racial differences in cerebrovascular disease may inform underlying mechanisms of HRP development and may ultimately help guide appropriate therapy.

OBJECTIVE: To determine the bilaterally asymmetrical associations between extracranial carotid artery atherosclerosis and ipsilateral middle cerebral artery (MCA) stenosis in symptomatic patients using magnetic resonance vessel wall imaging. Approach and Results: Patients with symptomatic carotid artery atherosclerosis were recruited from the Chinese Atherosclerosis Risk Evaluation, a multicenter study. All subjects underwent intracranial magnetic resonance angiography and extracranial carotid artery magnetic resonance imaging. Severe stenosis (stenosis ≥50%) of MCA, carotid moderate-to-severe stenosis (stenosis ≥50%), plaque compositions, and high-risk plaque on symptomatic side were evaluated in all subjects. Associations between ipsilateral MCA stenosis and extracranial carotid plaque features were evaluated. A total of 363 patients (mean age: 61.2±10.4 years old; 254 males) were included. In the left symptomatic cerebrovascular group (n=186), carotid moderate-to-severe stenosis (odds ratio [OR], 3.00 [95% CI, 1.03-8.79]; P=0.045), intraplaque hemorrhage (OR, 3.68 [95% CI, 1.21-11.19]; P=0.021), fibrous cap rupture (OR, 5.70 [95% CI, 1.60-20.31]; P=0.007), and high-risk plaque (OR, 2.95 [95% CI, 1.19-7.35]; P=0.020) were significantly associated with ipsilateral severe MCA stenosis, after adjusting for confounding factors. In the right symptomatic cerebrovascular group (n=177), severe MCA stenosis was significantly associated with ipsilateral carotid moderate-to-severe stenosis (OR, 3.98 [95% CI, 1.54-10.32]; P=0.004) but not with other extracranial carotid plaque features (all P>0.05), after adjusting for confounding factors. CONCLUSIONS: In the symptomatic arteries, vulnerable plaque features are independently associated with ipsilateral severe MCA stenosis on the left side, but this association is not found on the right side, indicating the associations of atherosclerotic disease between intracranial and extracranial carotid arteries are asymmetrical.

PURPOSE: To develop a fully automated vessel wall (VW) analysis workflow (fully automated and robust analysis technique for popliteal artery evaluation, FRAPPE) on the popliteal artery in standardized knee MR images. METHODS: Popliteal artery locations were detected from each MR slice by a deep neural network model and connected into a 3D artery centerline. Vessel wall regions around the centerline were then segmented using another neural network model for segmentation in polar coordinate system. Contours from vessel wall segmentations were used for vascular feature calculation, such as mean wall thickness and wall area. A transfer learning and active learning framework was applied in training the localization and segmentation neural network models to maintain accuracy while reducing manual annotations. This new popliteal artery analysis technique (FRAPPE) was validated against manual segmentation qualitatively and quantitatively in a series of 225 cases from the Osteoarthritis Initiative (OAI) dataset. RESULTS: FRAPPE demonstrated high accuracy and robustness in locating popliteal arteries, segmenting artery walls, and quantifying arterial features. Qualitative evaluations showed 1.2% of slices had noticeable major errors, including segmenting the wrong target and irregular vessel wall contours. The mean Dice similarity coefficient with manual segmentation was 0.79, which is comparable to inter-rater variations. Repeatability evaluations show most of the vascular features have good to excellent repeatability from repeated scans of same subjects, with intra-class coefficient ranging from 0.80 to 0.98. CONCLUSION: This technique can be used in large population-based studies, such as OAI, to efficiently assess the burden of atherosclerosis from routine MR knee scans.

BACKGROUND AND PURPOSE: To investigate differences in the characteristics of carotid atherosclerotic plaques of symptomatic subjects in northern and southern China using MRI. METHODS: Sixty-three subjects in northern China (mean age: 59.1±8.6 years, 45 men) and 56 subjects in southern China (mean age: 60.4±8.6 years, 38 men) were included. All subjects underwent carotid artery multicontrast vessel wall MRI. Plaque morphology, calcification, lipid-rich necrotic core, intraplaque haemorrhage, luminal surface disruption and high-risk plaque were measured and identified. All plaque characteristics were compared between subjects in northern and southern China using Mann-Whitney U test or χ2 test. RESULTS: Compared with subjects in southern China, those in northern China had significantly greater areas for lumen (57.7±14.9 mm2 vs 50.4±18.3 mm2, p=0.009), wall (38.4±13.1 mm2 vs 31.9±11.7 mm2, p<0.001) and total vessel (96.1±20.2 mm2 vs 82.4±22.7 mm2, p=0.001) and mean wall thickness (1.25±0.43 mm vs 1.13±0.40 mm, p=0.019). χ2 analysis showed that subjects in northern China tended to have a higher prevalence of intraplaque haemorrhage (14.3% vs 5.4%, p=0.106) and high-risk plaque (20.6% vs 10.7%, p=0.140) than those in southern China, although these differences were not statistically significant (all p>0.05). CONCLUSION: Subjects in northern China have significantly larger vessel size and may have a higher prevalence of vulnerable plaques than those in southern China. Our findings provide additional perspective to optimise the management of cerebrovascular disease in individuals in different regions in China. TRIAL REGISTRATION NUMBER: NCT02017756.

OBJECTIVE: Carotid bifurcation geometry has been believed to be a risk factor for the initiation of atherosclerosis because of its influence on hemodynamics. However, the relationships between carotid bifurcation geometry and plaque vulnerability are not fully understood. This study aimed to determine the association between carotid bifurcation geometry and plaque vulnerability using magnetic resonance vessel wall imaging. Approach and Results: A total of 501 carotid arteries with nonstenotic atherosclerosis were included from the cross-sectional, multicenter CARE II study (Chinese Atherosclerosis Risk Evaluation). Four standardized carotid bifurcation geometric parameters (bifurcation angle, internal carotid artery planarity, luminal expansion FlareA, and tortuosity Tort2D) were derived from time-of-flight magnetic resonance angiography. Presence of vulnerable plaque, which was characterized by intraplaque hemorrhage, large lipid-rich necrotic core, or disrupted luminal surface, was determined based on multicontrast carotid magnetic resonance vessel wall images. Vulnerable plaques (N=43) were found to occur at more distal locations (ie, near the level of flow divider) than stable plaques (N=458). Multivariable logistic regression showed that the luminal expansion FlareA (odds ratio, 0.45 [95% CI, 0.25-0.81]; P=0.008) was associated with plaque vulnerability after adjustment for age, sex, maximum wall thickness, plaque location, and other geometric parameters. CONCLUSIONS: Smaller luminal expansion at carotid bifurcation is associated with vulnerable plaque. The finding needs to be verified with longitudinal studies and the underlying mechanism should be further explored with hemodynamics measurement in the future.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

OBJECTIVES: To investigate the differences in characteristics of carotid plaques between patients Xining at high altitude and Jinan at sea level using magnetic resonance (MR) imaging. METHODS: Subjects were recruited from a cross-sectional, observational, multicenter imaging study of CARE-II study. Forty-nine (mean age 63.3 ± 12.0 years, 33 males) and 51 (mean age 64.5 ± 12.0 years, 34 males) patients were recruited from a site located in a high altitude region and a site located near sea level, respectively. All patients underwent multicontrast MR vessel wall imaging for carotid arteries on 3.0 T MR scanner. The carotid plaques features were compared between 2 patient groups. RESULTS: Compared with patients at sea level, those at high altitude had significantly greater lumen area (58.5 ± 17.8 mm2 versus 50.0 ± 19.6 mm2, P = .008), smaller maximum normalized wall index (48.6% ± 14.2% versus 57.8% ± 16.3%, P = .002), and smaller percentage volume of calcium (0.9% versus 5.6%, P < .001) in the symptomatic carotid artery. After adjustment for clinical risk factors including age, sex, systolic blood pressure, LDL-C, and statin use, these differences in plaque morphology and composition remained statistically significant. After further adjustment for normalized wall index as a measure of plaque burden, percentage volume of calcification was still significantly smaller in patients at high altitude area than that in patients at sea level area (P = .047). CONCLUSION: Symptomatic subjects from a high altitude area have lower plaque burden and less calcification in the carotid artery compared to those from an area near sea level.

Background and Purpose- High-resolution magnetic resonance imaging is capable of characterizing carotid atherosclerotic plaque morphology and composition. Most reported carotid plaque imaging techniques are 2-dimensional (2D) based with limited longitudinal coverage of ≈30 mm, which may be insufficient for complete visualization of extracranial carotid atheroma. A 3D black-blood imaging technique, motion-sensitized driven equilibrium prepared rapid gradient echo technique (3D-MERGE) can provide larger coverage. We sought to use 3D-MERGE to investigate carotid atherosclerosis plaque distribution and to analyze their correlation with clinical information and stroke risk factors. Methods- From 5 hospitals in China, 97 subjects suspected of recent stroke or transient ischemic attack were imaged with 3D-MERGE within 2 weeks of symptoms using 3T magnetic resonance imaging. Images were analyzed by 2 reviewers. Plaque length was calculated and categorized as plaques within, partially outside, or completely outside of typical 2D magnetic resonance imaging coverage. Associations between plaque features and clinical information, stroke risk factors were assessed. Results- Ninety-seven subjects with 194 carotid arteries (70 men and 27 women, mean age 60 years) were analyzed. Of the 136 plaques identified, 68 (50%) were within, 46 (33.8%) were partially outside, and 22 (16.2%) were completely outside of 2D magnetic resonance imaging coverage. Total plaque length was significantly positively associated with male sex (P<0.001), hypertension (P=0.011), and history of smoking (P<0.001). Hypertensive subjects were more likely to have at least one plaque completely outside the 2D magnetic resonance imaging coverage than nonhypertensive subjects (P=0.007). Conclusions- The 3D-MERGE allows for the identification of substantially more carotid plaques than 2D black-blood techniques. The extent and distribution of plaque, identified by the larger coverage afforded by 3D-MERGE, were found to correlate significantly with male sex and risk factors that are common among patients with stroke, including hypertension and history of cigarette smoking.

AIM: It remains unclear whether physicians should change intubation approaches after the failed first attempt. We aimed to determine the rescue intervention approaches associated with a higher success rate at the second attempt in the emergency department (ED). METHODS: We analyzed the data from a prospective, multicenter, observational study - the second Japanese Emergency Airway Network Study. The current analysis included all patients who underwent emergency intubation from February 2012 through November 2017. We defined a rescue intubation attempt as a second intubation attempt with any change in intubation approaches (i.e., change in methods, devices, or intubators) from the failed first attempt. The outcome measure was second-attempt success. RESULTS: Of 2,710 patients with a failed first attempt, 43% underwent a second intubation attempt with changes in intubation approach (i.e., rescue intubation). Rescue intubation attempts were associated with a higher second-attempt success rate compared to non-rescue intubation attempts (adjusted odds ratio [OR], 1.78; 95% confidence interval [CI], 1.50-2.12). The rescue intubation approaches associated with a higher second-attempt success were changes from non-rapid sequence intubation (RSI) to RSI (adjusted OR, 2.04; 95% CI, 1.12-3.75), from non-emergency medicine (EM) residents to EM residents (adjusted OR, 2.02; 95% CI, 1.44-2.82), and from non-EM attending physicians to EM attending physicians (adjusted OR, 2.82; 95% CI, 2.14-3.71). CONCLUSIONS: In this large multicenter study, rescue interventions were associated with a higher second-attempt success rate. The data also support the use of RSI and backup by EM residents or EM attending physicians to improve the airway management performance after a failed attempt in the ED.

To determine whether ketamine use for tracheal intubation, compared to other sedative use, is associated with a lower risk of post-intubation hypotension in hemodynamically-unstable patients in the emergency department (ED), we analyzed the data of a prospective, multicenter, observational study-the second Japanese Emergency Airway Network (JEAN-2) Study-from February 2012 through November 2017. The current analysis included adult non-cardiac-arrest ED patients with a pre-intubation shock index of ≥0.9. The primary exposure was ketamine use as a sedative for intubation, with midazolam or propofol use as the reference. The primary outcome was post-intubation hypotension. A total of 977 patients was included in the current analysis. Overall, 24% of patients developed post-intubation hypotension. The ketamine group had a lower risk of post-intubation hypotension compared to the reference group (15% vs 29%, unadjusted odds ratio [OR] 0.45 [95% CI 0.31-0.66] p < 0.001). This association remained significant in the multivariable analysis (adjusted OR 0.43 [95% CI 0.28-0.64] p < 0.001). Likewise, in the propensity-score matching analysis, the patients with ketamine use also had a significantly lower risk of post-intubation hypotension (OR 0.47 [95% CI, 0.31-0.71] P < 0.001). Our observations support ketamine use as a safe sedative agent for intubation in hemodynamically-unstable patients in the ED.

Correct stratification of ischemic stroke risk allows for the proper treatment of carotid atherosclerotic disease. We seek to differentiate plaque types based on stenosis level and plaque morphology. The Chinese Atherosclerosis Risk Evaluation (CARE-II) study is a cross-sectional, observational, multicenter study to assess carotid atherosclerotic plaques in symptomatic subjects using vessel wall magnetic resonance imaging. Plaque morphology and presence of plaque components were reviewed using multi-contrast magnetic resonance imaging. The carotid arteries were divided into four groups based on stenosis level and plaque components. Out of 1072 ischemic stroke subjects, 452 ipsilateral side carotid arteries were included. Significant stenosis (SS) (≥50% stenosis) with high-risk plaque (HRP) features was present in 37 arteries (8.2%), SS(+)/HRP(-) in 29 arteries (6.4%), SS(-)/HRP(+) in 57 arteries (12.6%), and SS(-)/HRP(-) in 329 arteries (72.8%). The prevalence of SS(-)/HRP(+) arteries in this cohort was substantial and had greater wall thickness than the SS(+)/HRP(-) group. These arteries may be misclassified for carotid revascularization by current guidelines based on the degree of luminal stenosis only. These findings have implications for further studies to assess stroke risk using vessel wall imaging.

Emergency airway management is one of the vital resuscitative procedures undertaken in the emergency department (ED). Despite its clinical and research importance in the care of critically ill and injured patients, earlier studies have documented suboptimal intubation performance and high adverse event rates with a wide variation across the EDs. The optimal emergency airway management strategies remain to be established and their dissemination to the entire nation is a challenging task. This article reviews the current published works on emergency airway management with a focus on the use of airway management algorithms as well as the importance of first-pass success and systematic use of rescue intubation strategies. Additionally, the review summarizes the current evidence for each of the important airway management processes, such as assessment of the difficult airway, preparation (e.g., positioning and oxygenation), intubation methods (e.g., rapid sequence intubation), medications (e.g., premedications, sedatives, and neuromuscular blockades), devices (e.g., direct and video laryngoscopy and supraglottic devises), and rescue intubation strategies (e.g., airway adjuncts and rescue intubators), as well as the airway management in distinct patient populations (i.e., trauma, cardiac arrest, and pediatric patients). Well-designed, rigorously conducted, multicenter studies that prospectively and comprehensively characterize emergency airway management should provide clinicians with important opportunities for improving the quality and safety of airway management practice. Such data will not only advance research into the determination of optimal airway management strategies but also facilitate the development of clinical guidelines, which will, in turn, improve the outcomes of critically ill and injured patients in the ED.

AIM: Methylxanthines are no longer recommended for emergency department (ED) patients with acute asthma according to international guidelines. We aimed to describe the current methylxanthine use for acute asthma and to determine factors related to its use in the ED. METHODS: We undertook a multicenter retrospective study in 23 EDs across Japan. From each participating hospital, we randomly identified 60 ED patients aged 18-54 years with acute asthma from 2009 through 2011. We examined the associations of ED and patient characteristics with methylxanthine use by constructing a multivariable logistic regression model adjusting for a predefined set of ED- and patient-level factors. RESULTS: Among 1,380 patients, methylxanthines were used for 79 patients (5.7%, 95% confidence interval [CI], 4.6-7.0%). The proportion of methylxanthine treatment varied substantially among EDs, ranging from 0% to 26.1%. In the multivariable analysis, the number of annual ED patients with acute asthma (odds ratio [OR] per 100 increase in annual asthma patients, 0.12; 95% CI, 0.04-0.34; P < 0.001) and having a protocol for asthma treatment (OR 2.91; 95% CI, 1.06-8.00; P = 0.04) at the ED level, and systemic corticosteroid use (OR 6.39; 95% CI, 3.34-12.22; P < 0.001) at the patient level were associated with likelihood of methylxanthine use. CONCLUSIONS: In this multicenter study, approximately 6% of ED patients with acute asthma were treated with methylxanthines, with a wide variation across EDs. The number of annual ED patients with acute asthma was significantly associated with a lower likelihood of methylxanthine use, whereas having an ED asthma treatment protocol and systemic corticosteroid use in the ED were associated with a higher likelihood of methylxanthine treatment.

Objective- Diabetes mellitus is associated with high-risk atherosclerotic plaques. This study aimed to compare characteristics of carotid atherosclerotic plaques in symptomatic Chinese diabetic and nondiabetic patients using vessel wall magnetic resonance imaging. Approach and Results- Patients with cerebral ischemic symptoms in the anterior circulation and carotid atherosclerotic plaque determined by ultrasound were recruited from a cross-sectional, observational, multicenter study of CARE-II (Chinese Atherosclerosis Risk Evaluation). All patients underwent magnetic resonance imaging for carotid arteries. The morphological and compositional characteristics of carotid plaques were compared between diabetic and nondiabetic patients using linear (continuous variables) and logistic regression (binary variables). In a total of 584 recruited patients, 182 (31.2%) had diabetes mellitus. From the univariate analysis, diabetic patients had significantly greater mean wall area (33.7 versus 31.1 mm2; P=0.002), maximum wall thickness (3.2 versus 2.8 mm; P<0.001), and mean normalized wall index (43.8% versus 41.0%; P<0.001) and had significantly higher prevalence of calcification (51.6% versus 36.6%; P=0.001), lipid-rich necrotic core (77.5% versus 58.5%; P<0.001), and high-risk plaque (29.7% versus 19.9%; P=0.011) than nondiabetic patients. After adjusting for clinical characteristics, the differences in presence of calcification ( P=0.018) and lipid-rich necrotic core ( P=0.001) remained statistically significant. Conclusions- Symptomatic Chinese diabetic patients are more likely to have carotid plaques with calcification and lipid-rich necrotic core than nondiabetic patients, suggesting that diabetic patients may develop more severe atherosclerotic disease that should be accounted for in their clinical management.

Atherosclerotic cardiovascular disease remains a worldwide epidemic and one of the leading causes of death nowadays. Vessel wall imaging can be used to understand the development and progression of atherosclerosis, but it is rarely done because of the high cost. We recently identified the Osteoarthritis Initiative, a large prospective cohort study of knee osteoarthritis, which might serve as a valuable source for atherosclerosis research with its serial knee magnetic resonance imaging data. We have found that these images are suitable for vessel wall image analysis of the lower extremity arteries. Here, we will introduce the Osteoarthritis Initiative data set and explain why it could be used for cardiovascular research purposes. Also, we will briefly comment on peripheral artery atherosclerosis as it is covered in the Osteoarthritis Initiative image data set and review the use of vessel wall imaging for studying atherosclerosis. We think data mining of imaging studies, not originally designed on cardiovascular research, can not only maximize the value of the imaging data set but also boost our understanding of atherosclerosis.

OBJECTIVE: The objective is to establish interscan, inter- and intra-rater reproducibility of a multicontrast three-dimensional contrast-enhanced intracranial vessel wall (IVW) MRI protocol with 0.6 mm acquired (0.3 mm interpolated) isotropic resolution in the detection of intracranial atherosclerosis. METHODS: Subjects with established intracranial atherosclerosis were prospectively recruited and underwent two contrast-enhanced three-dimensional IVW scans within a 2-week period. Four raters with varying degrees of vessel wall imaging interpretation experience, through an iterative training process developed guidelines for plaque identification with no, possible and definite plaque categories. Using these guidelines, the raters reviewed the cases in pairs (consensus rating), while blinded to the interpretations of the other pair, clinical reports and patient history. The rater pairs reviewed 19 segments per patient for the presence and location of atherosclerotic plaques. Inter-scan, inter rater and intra rater reproducibility were assessed. RESULTS: 19 subjects were scanned twice, with 361 total segments reviewed and 304-324 evaluable segments analyzed in the different reproducibility assessments. Overall inter-rater agreement for possible and definite plaque was 88.9 % [κ = 0.73; 95% confidence interval (CI) (0.62-0.81)], inter-scan/intra-rater agreement was 82.1 % [κ = 0.58; 95% CI (0.48-0.70)] and inter-scan/inter-rater agreement of 84.5% [κ = 0.64; 95% CI (0.51 - 0.76)]. CONCLUSION: Contrast-enhanced IVW imaging, with the utilization of detailed plaque definition guidelines for image review, can be a reproducible technique for the evaluation of intracranial atherosclerosis. ADVANCES IN KNOWLEDGE: This work is the first to establish reproducibility of IVW for plaque identification with and without contrast. Reproducibility using contrast is important as most IVW applications rely on lesion enhancement.

OBJECTIVE:: Identification of aneurysms at risk for rupture is important and challenging. We sought to evaluate if intracranial vessel wall (IVW) imaging characteristics of unruptured aneurysms correlate with clinical risk factors for rupture. METHODS:: Patients with unruptured intracranial aneurysms were prospectively recruited and underwent a multi contrast 3D IVW protocol between April 6, 2016 and August 29, 2017. Two independent raters, blinded to aneurysm vulnerability, evaluated each aneurysm for wall enhancement, extent of enhancement in terms of the numbers of quadrants enhancing circumferentially, intensity of enhancement, and qualitative wall thinning. PHASES score was calculated for each aneurysm. Univariate logistic regression analysis was used to compare IVW characteristics between aneurysms at higher clinical risk for rupture (PHASES score > 3) and lower clinical risk for rupture (PHASES score ≤ 3). RESULTS:: 45 patients with 65 unruptured aneurysms were analyzed; 38 aneurysms with PHASES score > 3 (58%) and 27 aneurysms with PHASES score ≤ 3 (42%). Aneurysms with PHASES score > 3 were more likely to demonstrate enhancement (42.1% vs 14.8%, p = 0.022), greater extent of enhancement (mean: 2.9 vs 2.2 quadrants, p = 0.063), and wall thinning (9.2% vs 0%, p = 0.044). Inter-reader agreement was moderate-to-good for the presence (κ = 0.64), extent (κ = 0.64), and intensity of enhancement (κ = 0.60) but relatively low for wall thinning (κ = 0.25). CONCLUSION:: Aneurysms at higher risk of rupture by PHASES score are more likely to demonstrate wall enhancement, more diffuse enhancement, and wall thinning on IVW. ADVANCES IN KNOWLEDGE:: This study prospectively compares IVW-detected wall enhancement and thinning between unruptured aneurysms stratified into high and low risk groups by clinical scores (PHASES) of vulnerability.

AIM: To compare the tracheal intubation performance between video laryngoscopy (VL) and direct laryngoscopy (DL) in patients with cardiac arrest in the ED. METHODS: This is an analysis of the data from a prospective, multicentre study of 15 EDs in Japan. We included consecutive adult patients with cardiac arrest who underwent intubation with VL or DL from 2012 through 2016. The primary outcome was first-attempt success. The secondary outcomes were glottic visualisation assessed with Cormack grade (1 vs. 2-4) and occurrence of oesophageal intubation. To examine the between-device difference in outcome risks, we analysed the whole data and 1:1 propensity score matched data. RESULTS: Among 9694 patients who underwent intubation in the EDs, 3360 cardiac arrests (35%) were included in the analysis (90% were non-traumatic cardiac arrests). The first-attempt success rate was higher in the VL group compared to those in the DL (78% vs 70%; unadjusted OR 1.61 [95%CI 1.26-2.06] P < 0.001). This association remained significant after adjusting for six potential confounders and within-ED clustering (adjusted OR 1.33 [95%CI 1.03-1.73] P = 0.03). VL use was also associated with a better glottic visualisation (adjusted OR 3.84 [95%CI 2.81-5.26] P < 0.001) and lower rate of oesophageal intubation (adjusted OR 0.45 [95%CI 0.24-0.85] P = 0.01) compared to DL. These results were consistent in the propensity score matched analysis. CONCLUSIONS: Based on large multicentre prospective data of ED patients with cardiac arrest, the use of VL was associated with a higher first-attempt success rate compared to DL, with a better glottic visualisation and lower oesophageal intubation rate.

BACKGROUND: Studies in the non-emergency department (ED) settings have reported the relationships of post-intubation hypertension with poor patient outcomes. While ED-based studies have examined post-intubation hypotension and its sequelae, little is known about, post-intubation hypertension and its risk factors in the ED settings. In this context, we aimed to identify the incidence of post-intubation hypertension in the ED, and to test the hypothesis that repeated intubation attempts are associated with an increased risk of post-intubation hypertension. METHODS: This study is a secondary analysis of the data from a multicenter prospective observational study of emergency intubations in 15 EDs from 2012 through 2016. The analytic cohort comprised all adult non-cardiac-arrest patients undergoing orotracheal intubation without pre-intubation hypotension. The primary exposure was the repeated intubation attempts, defined as ≥2 laryngoscopic attempts. The outcome was post-intubation hypertension defined as an increase in systolic blood pressure (sBP) of >20% along with a post-intubation sBP of >160 mmHg. To investigate the association of repeated intubation attempts with the risk of post-intubation hypertension, we fit multivariable logistic regression models adjusting for ten potential confounders and patient clustering within the EDs. RESULTS: Of 3,097 patients, the median age was 69 years, 1,977 (64.0%) were men, and 991 (32.0%) underwent repeated intubation attempts. Post-intubation hypertension was observed in 276 (8.9%). In the unadjusted model, the incidence of post-intubation hypertension did not differ between the patients with single intubation attempt and those with repeated attempts (8.5% versus 9.8%, unadjusted P = 0.24). By contrast, after adjusting for potential confounders and patient clustering in the random-effects model, the patients who underwent repeated intubation attempts had a significantly higher risk of post-intubation hypertension (OR, 1.56; 95% CI, 1.11-2.18; adjusted P = 0.01). CONCLUSIONS: We found that 8.9% of patients developed post-intubation hypertension, and that repeated intubation attempts were significantly associated with a significantly higher risk of post-intubation hypertension in the ED.

BACKGROUND: The anesthesia literature has reported that pre-intubation fentanyl use is associated with post-intubation hypotension which is a risk factor of poor post-emergency department (ED) prognosis. However, little is known about the relations between fentanyl use for intubation and post-intubation hypotension in the ED. We aimed to determine whether pretreatment with fentanyl was associated with a higher risk of post-intubation hypotension in the ED. METHODS: We conducted a secondary analysis of data of ED airway management collected from a multicenter prospective study of 14 Japanese EDs from February 2012 through November 2016. We included all adult non-cardiac-arrest patients who underwent rapid sequence intubation for medical indication. Patients were divided into fentanyl and non-fentanyl groups. The primary outcome was post-intubation hypotension (systolic blood pressure ≤90mmHg) in the ED. RESULTS: Of 1263 eligible patients, 466 (37%) patients underwent pretreatment with fentanyl. The fentanyl group had a higher risk of post-intubation hypotension (17% vs. 6%; unadjusted OR, 1.73; 95%CI, 1.01-2.97; P=0.048) compared to the non-fentanyl group. In the multivariable analysis adjusting for age, sex, weight, principal indication, sedatives, intubator's specialty, number of intubation attempts, and patient clustering within EDs, the fentanyl group had a higher risk of post-intubation hypotension (adjusted OR, 1.87; 95%CI, 1.05-3.34; P=0.03) compared to the non-fentanyl group. In the sensitivity analysis using propensity score matching, this association remained significant (OR, 3.17; 95%CI, 1.96-5.14; P<0.01). CONCLUSION: In this prospective multicenter study of ED airway management, pretreatment with fentanyl in rapid sequence intubation was associated with higher risks of post-intubation hypotension.

AIM: The target Geriatric Nutritional Risk Index (GNRI) for patients on chronic maintenance hemodialysis is unclear. We aimed to determine the relationship between the GNRI and independent walking ability in such patients. METHODS: In the present retrospective cohort study, 90 patients receiving chronic maintenance hemodialysis were included. Logistic regression analyses were carried out to evaluate the relationship between the GNRI and independent walking ability. Receiver operating characteristic curve analysis was carried out to determine the cut-off GNRI for predicting independent walking ability. RESULTS: Multivariate logistic regression analysis showed significant differences in age (odds ratio [OR] 0.8, 95% confidence interval [CI] 0.6-0.9), creatinine generation rate percentage (OR 1.1, 95% CI 1.0-1.2), GNRI (OR 1.4, 95% CI 1.1-1.8; P < 0.01) and urea removal rate (OR 0.3, 95% CI 0.1-0.9; P < 0.05). The cut-off GNRI for independent walking ability was 86.7 (area under the curve 0.80, sensitivity 92.1%, specificity 66.7%, positive hit ratio 86.6%, negative hit ratio 78.3%). The factors correlated with survival in the univariate analysis were the GNRI, equilibrated Kt/V, urea removal rate, clear space rate, salt intake amount (P < 0.01), number of days of hospitalization and %creatinine generation rate (P < 0.05). The Cox proportional hazard regression model showed an OR of 0.77 (95% CI 0.32-1.8) at a GNRI <86/GNRI ≥86. In the multivariate survival analysis, we observed no significant differences in any of the factors. CONCLUSIONS: GNRI was correlated with walking ability, which indicated that GNRI might predict future walking ability; also, a GNRI of 87 might be the target for maintaining walking ability. Geriatr Gerontol Int 2018; 18: 1556-1561.

OBJECTIVE: Early atherosclerosis is often undetected due in part to compensatory enlargement of the outer wall, termed positive remodeling. Variations in hemodynamic conditions and clinical factors influence the patterns of remodeling. The carotid artery provides an opportunity to examine these variations because of the unique geometry of the carotid bulb. This study aimed to determine differences in remodeling of the common, internal, and bifurcation segments of the carotid using magnetic resonance imaging. APPROACH AND RESULTS: Carotid arteries of 525 subjects without history of cardiovascular disease were imaged by magnetic resonance imaging. The carotid artery was divided into 3 segments: common carotid artery; bifurcation; and internal carotid artery. Remodeling patterns were characterized using linear regression analysis of lumen and total vessel areas (dependent variables) compared with maximum wall thickness (independent variable) for each segment, adjusted for age, sex, and height. The common carotid artery demonstrated a pattern consistent with positive remodeling, whereas the bifurcation demonstrated negative remodeling. The internal carotid artery demonstrated a mixed pattern of outer wall expansion and lumen constriction. Females and subjects with diabetes mellitus showed more positive remodeling, hypertension was associated with attenuated positive remodeling, and those with hypercholesterolemia showed more negative remodeling. CONCLUSIONS: In this cohort of 55- to 80-year-old individuals without history of cardiovascular disease, the pattern of early carotid artery remodeling was segment specific and appeared to be associated with sex and clinical characteristics. These findings provide the groundwork for longitudinal studies to define local and systemic factors such as hemodynamic and clinical conditions on carotid artery remodeling.

OBJECTIVES: A postprocessing technique termed 3D true-phase polarity recovery with independent phase estimation using three-tier stacks based region growing (3D-TRIPS) was developed, which directly reconstructs phase-sensitive inversion-recovery images without acquisition of phase-reference images. The utility of this technique is demonstrated in myocardial late gadolinium enhancement (LGE) imaging. MATERIALS AND METHODS: A data structure with three tiers of stacks was used for 3D-TRIPS to directly achieve reliable region growing for successful background-phase estimation. Fifteen patients undergoing postgadolinium 3D phase-sensitive inversion recovery (PSIR) cardiac LGE magnetic resonance imaging (MRI) were recruited, and 3D-TRIPS LGE reconstructions were compared with standard PSIR. Objective voxel-by-voxel comparison was performed. Additionally, blinded review by two radiologists compared scar visibility, clinical acceptability, voxel polarity error, or groups and blurring. RESULTS: 3D-TRIPS efficiently reconstructed postcontrast phase-sensitive myocardial LGE images. Objective analysis showed an average 95% voxel-by-voxel agreement between 3D-TRIPS and PSIR images. Blinded radiologist review demonstrated similar image quality between 3D-TRIPS and PSIR reconstruction. CONCLUSION: 3D-TRIPS provided similar image quality to PSIR for phase-sensitive myocardial LGE MRI reconstruction. 3D-TRIPS does not require acquisition of a reference image and can therefore be used to accelerate phase-sensitive LGE imaging.

Obesity is deemed to increase the risk of difficult tracheal intubation. However, there is a dearth of research that examines the relationship of obesity with intubation success and adverse events in the emergency department (ED). We analyzed the data from a prospective, observational, multicenter study-the Japanese Emergency Airway Network (JEAN) 2 study from 2012 through 2016. We included all adults (aged ≥18 years) who underwent tracheal intubation in the ED. Patients were categorized into three groups according to their body mass index (BMI): lean (<25.0 kg/m²), overweight (25.0-29.9 kg/m²), and obesity (≥30.0 kg/m²). Outcomes of interest were intubation success on the first attempt and intubation-related adverse events. Of 6,889 patients who are eligible for the analysis, 5,370 patients (77%) were lean, 1,177 (17%) were overweight, and 342 (4%) were obese. Compared to the lean patients, the intubation success rates were significantly lower in the overweight and obese patients (70.9% in lean, 66.4% in overweight, and 59.3% in obese patients; P<0.001). In the multivariable analysis, compared to the lean patients, overweight (adjusted odds ratio [OR], 0.85; 95%CI, 0.74-0.98) and obese (adjusted OR, 0.62; 95%CI, 0.49-0.79) patients had a significantly lower success rate on the first attempt. Additionally, obesity was significantly associated with a higher risk of adverse events (adjusted OR, 1.62; 95%CI, 1.23-2.13). Based on the data from a multicenter prospectively study, obesity was associated with a lower success rate on the first intubation attempt and a higher risk of adverse event in the ED.

OBJECTIVES: Continuous surveillance of emergency airway management practice is imperative in improving quality of care and patient safety. We aimed to investigate the changes in the practice of emergency airway management and the related outcomes in the emergency departments (EDs) in Japan. METHODS: We conducted an analysis of the data from two prospective, observational, multicentre registries of emergency airway management-the Japanese Emergency Airway Network (JEAN)-1 and -2 Registries from April 2010 through May 2016. RESULTS: We recorded 10,927 ED intubations (capture rate, 96%); 10,875 paediatric and adult patients were eligible for our analysis. The rate of rapid sequence intubation (RSI) use as the initial intubation method significantly increased from 28% in 2010 to 53% in 2016 (Ptrend=0.03). Likewise, the rate of video laryngoscope (VL) use as the first intubation device increased significantly from 2% in 2010 to 40% in 2016 (Ptrend<0.001), with a significant decrease in the rate of direct laryngoscope use from 97% in 2010 to 58% in 2016 (Ptrend<0.001). Concurrent with these changes, the overall first-attempt success rate also increased from 68% in 2010 to 74% in 2016 (Ptrend=0.02). By contrast, the rate of adverse events did not change significantly over time (Ptrend=0.06). CONCLUSION: By using data from two large, multicentre, prospective registries, we characterised the current emergency airway management practice, and identified their changes in Japan. The data demonstrated significant increases in the rate of RSI and VL use on the first attempt and the first-attempt success rate over the 6-year study period.

BACKGROUND: Although airway management with neuromuscular blockade (NMB) alone is discouraged in the emergency department (ED), our previous study demonstrated that many patients were intubated using NMBs alone without sedatives. To refute this practice, we sought to compare the intubation success and adverse event rates between NMBs only and rapid sequence intubation (RSI). METHODS: This is a secondary analysis of the data from a prospective observational study of ED patients in 13 hospitals who underwent emergency airway management from April 2010 to August 2012. The primary outcome was intubation success rate on first attempt. The secondary outcomes were the intubation success rate in ≤2 attempts and the intubation-related adverse event rate. We compared these outcomes between intubation attempts using NMB alone and RSI. We fit multivariable logistic regression models adjusting for potential confounders (age, sex, weight, primary indication for intubation, and training level of intubators). RESULTS: Overall, 852 patients were eligible for this analysis, with 114 (13%) intubated with NMB alone and 738 (87%) with RSI. Between the NMB-alone and RSI groups, no significant differences were observed in the success rate on the first attempt (70 vs. 73%; P = 0.48) or in ≤2 attempts (89 vs. 91%; P = 0.46), or in the adverse event rate (11 vs. 12%; P = 0.58). Similarly, after adjusting for confounders, no significant differences were observed in any of these outcomes (all P > 0.05). CONCLUSIONS: In this analysis of data from a large multicenter study of ED patients, we found no superior effectiveness of intubation with NMB alone when compared to RSI. Our data lend significant support to the concept that intubation with NMB alone should be avoided in the ED.

OBJECTIVES: We sought to compare the characteristics of patients with asthma presenting to the emergency department (ED) during the night-time with those of patients presenting at other times of the day, and to determine whether the time of ED presentation is associated with the risk of hospitalisation. DESIGN AND SETTING: A multicentre chart review study of 23 EDs across Japan. PARTICIPANTS: Patients aged 18-54 years with a history of physician-diagnosed asthma, presented to the ED between January 2009 and December 2011 OUTCOME MEASURES: The outcome of interest was hospitalisation, including admissions to an observation unit, inpatient unit and intensive care unit. RESULTS: Among the 1354 patients (30.1% in the night-time group vs 69.9% in the other time group) included in this study, the median age was 34 years and ∼40% were male. Overall 145 patients (10.7%) were hospitalised. Patients in the night-time group were more likely to have a shorter duration of symptoms (≤3 hours) before ED presentation than those in the other time group (25.9% in night-time vs 13.4% in other times; p<0.001). In contrast, there were no significant differences in respiratory rate, initial peak expiratory flow or ED asthma treatment between the two groups (p>0.05). Similarly, the risk of hospitalisation did not differ between the two groups (11.3% in night-time vs 10.5% in other times; p=0.65). In a multivariable model adjusting for potential confounders, the risk of hospitalisation in the night-time group was not statistically different from the other time group (OR, 1.10; 95% CI 0.74 to 1.61; p=0.63). CONCLUSIONS: This multicentre study in Japan demonstrated no significant difference in the risk of hospitalisations according to the time of ED presentation.

OBJECTIVE: To determine whether the success rate of repeated attempts at tracheal intubation by a single intubator was lower than those by alternate intubators in the emergency department (ED). METHODS: An analysis of data from a multicentre prospective registry (Japanese Emergency Airway Network Registry) of 13 academic and community EDs in Japan between April 2010 and August 2012. We included all adult and paediatric patients who underwent repeated attempts at tracheal intubation in the ED. We compared the intubation success rates at the second and third attempts between attempts at intubation by a single intubator who performed the previous attempts, and the attempts by alternate intubators. RESULTS: We recorded 4094 patients (capture rate, 96%); 1289 patients with repeated attempts at tracheal intubation were eligible for this study. Among these, 871 patients (68%) had a second attempt at intubation by single intubators. At the second attempt, tracheal intubation by a single intubator was associated with a decreased success rate (adjusted odds ratio or AOR, 0.50; 95% CI 0.36 to 0.71), compared with alternate intubators. At the third attempt, intubation by a single intubator was also associated with a decreased success rate (58% vs 70%; unadjusted OR, 0.58; 95% CI 0.38 to 0.89). However, after adjustment for potential confounders, the association lost statistical significance (AOR, 0.89; 95% CI 0.52 to 1.56). CONCLUSIONS: In this large multicentre study of ED patients undergoing tracheal intubation, second attempts at intubation by a single intubator, compared with those by alternate intubators, were independently associated with a decreased success rate.

BACKGROUND: Evidence to predict difficult intubation remains scarce in the emergency department (ED) setting. A previously defined clinical decision rule, the modified LEMON criteria, may provide a reliable and reproducible means of identifying difficult intubations. We aimed to prospectively evaluate the external validity of the modified LEMON criteria in the EDs. METHODS: We conducted a 13-center prospective observational study, the second Japanese Emergency Airway Network study. We prospectively collected data on all patients undergoing intubations in the ED from February 2012 through September 2014. The primary outcomes were sensitivity, specificity, and predictive values of the modified LEMON criteria for predicting difficult intubation (≥2 attempts by emergency attending physicians or anesthesiologists). RESULTS: The database recorded a total of 4034 encounters (capture rate, 96%) in the EDs. Of these, 3313 patients (84%) underwent the intubation attempt with a direct laryngoscope and 610 patients (16%) with a video laryngoscope. The proportion of difficult intubation was 5.4% (95% confidence interval [CI], 4.7%-6.2%) in the direct laryngoscope group and 7.4% (95% CI, 5.6%-9.7%) in the video laryngoscope group. The sensitivity was 85.7% (95% CI, 79.3%-90.4%) with direct laryngoscope and 94.9% (95% CI, 83.5%-98.6%) with video laryngoscope. The specificity was 47.6% (95% CI, 47.2%-47.9%) and 40.3% (95% CI, 39.4%-40.6%), respectively. The negative predictive value was 98.2% (95% CI, 97.5%-98.8%) and 99.0% (95% CI, 96.6%-99.7%), respectively. CONCLUSIONS: In this multicenter prospective study, we found a high sensitivity and a negative predictive value of the modified LEMON criteria for predicting difficult intubation. The modified LEMON might assist ED providers in better identifying difficult intubations.

OBJECTIVES: Emergency department (ED) visits for asthma exacerbation reflect a failure of longitudinal asthma management. However, little is known about the characteristics of patients with frequent ED visits (≥2 visits in a 1-year period). We aimed to characterise the adult patients who frequently presented to the ED for asthma exacerbation in Japan. DESIGN: A multicentre chart review study of 23 EDs across Japan. PARTICIPANTS: Adults aged 18-54 years who presented to the ED with asthma exacerbation from 2009 to 2011. OUTCOME MEASURES: Frequency of ED visits for asthma exacerbation in a 1-year period, including the index ED visit. RESULTS: Of the 1002 eligible patients, 218 (22%) had frequent ED visits, accounting for 48% of total ED visits for asthma exacerbation in the 1-year period. Specifically, 12% had 2 ED visits and 10% had ≥3 visits. In these patients, guideline-recommended chronic management was suboptimal. For example, among patients with ≥3 ED visits, only 63% were treated with inhaled corticosteroids and 49% were current smokers. In a multinomial logistic regression model, markers of chronic asthma severity (history of hospitalisation for asthma and use of inhaled corticosteroids) were significantly associated with a higher frequency of ED visits (both p<0.05). CONCLUSIONS: This multicentre study in Japan demonstrated that many patients are frequent ED users for asthma exacerbation. We also found that their asthma control management is suboptimal, most likely contributing to worse chronic severity and more frequent ED visits. Further dissemination and adoption of evidence-based guidelines are required to reduce asthma morbidity in this high-risk population.

AIM: To examine the success rates of emergency department airway management by resident physicians in Japan. METHODS: We conducted an analysis of a multicentre prospective registry (Japanese Emergency Airway Network Registry) of 13 academic and community emergency departments in Japan. We included all patients who underwent emergency intubation performed by postgraduate year 1 to 5 transitional or emergency medicine residents (resident physicians) between April 2010 and August 2012. Outcome measures were success rates by the first intubator, and by rescue intubator, according to the level of training. RESULTS: We recorded 4,094 intubations (capture rate, 96%); 2,800 attempts (2,800/4,094; 68%; 95% confidence interval (CI), 67%-70%) were initially performed by resident physicians. Overall success rate on the first attempt was 63% (1,767/2,789; 95%CI, 61%-64%); the rate improved over the first 3 years of training before reaching a plateau (P trend < 0.001). Success rate by the first intubator was 78% (2,185/2,800; 95%CI, 76%-79%); the rate steadily improved as level of training increased (P trend < 0.001). Of 597 failed intubation attempts by the first intubator, 41% (247/597; 95%CI, 37%-45%) of rescue attempts were performed by resident physicians. Success rate on the first rescue attempt was 76% (187/247; 95%CI, 70%-81%), and success rate by first rescue intubator was 89% (220/247; 95%CI, 85%-93%). These rates on rescue attempts steadily improved as level of training increased (both P trend < 0.001). Intubations were ultimately successful in 2,778 encounters (99.6%). CONCLUSION: In this multicentre study characterizing emergency airway management across Japan, we observed that emergency department intubations were primarily managed by resident physicians with acceptably high success rates overall.

OBJECTIVE: After the Great Eastern Japan Earthquake and tsunami, the World Health Organization cautioned that evacuees at shelters would be at increased risk of infectious disease transmission; however, the frequency that occurred in this population was not known. METHODS: We reviewed medical charts of evacuees who visited medical clinics at 6 shelters from March 19, to April 8, 2011. Excluded were patients who did not reside within the shelters or whose medical records lacked a name or date. We investigated the frequency of and cumulative incidences of acute respiratory infection [ARI], acute gastroenteritis, acute jaundice syndrome, scabies, measles, pertussis, and tetanus. RESULTS: Of 1364 patients who visited 6 shelter clinics, 1167 patients (86.1%) were eligible for the study. The median total number of evacuees was 2545 (interquartile range [IQR], 2277-3009). ARI was the most common infectious disease; the median number of patients with ARI was 168.8 per week per 1000 evacuees (IQR, 64.5-186.1). Acute gastroenteritis was the second most common; the median number of patients was 23.7 per week per 1000 evacuees (IQR, 5.1-24.3). No other infectious diseases were observed. The median cumulative incidence of ARI per 1000 evacuees in each shelter was 13.1 person-days (IQR, 8.5-18.8). The median cumulative incidence of gastroenteritis was 1.6 person-days (IQR, 0.3-3.4). CONCLUSION: After the Great Eastern Japan Earthquake and tsunami, outbreaks of ARI and acute gastroenteritis occurred in evacuation shelters.

AIM: The number of institutions providing Anglo-American model emergency medicine has increased with the rise in its social demand in Japan. The ER Committee of the Japanese Association for Acute Medicine has introduced a residency model for use in Japanese hospitals that have adopted the Anglo-American emergency medicine model. Despite the critical importance of its quality, no studies have examined Japanese emergency medicine residents' level of satisfaction with their training. This study investigated their residency and career satisfaction, and factors associated with satisfaction. METHODS: We developed a cross-sectional, anonymous survey. Data were obtained from 67 Anglo-American model emergency medicine residents in Japan in February 2010. Data were analyzed with factor analysis and multivariable analysis with a logistic regression model. RESULTS: Response rate was 100% (n = 67). Overall, 50.7% and 67.2% of residents reported high residency and career satisfaction, respectively. Factor analysis derived four factors: working conditions; stress reduction; training systems; education. Logistic regression analysis revealed that the training system factor was significantly associated with high residency satisfaction (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.2-8.4) and the stress reduction factor was significantly associated with high career satisfaction (OR, 3.0; 95%CI, 1.2-8.4). A total of 28.8% reported intentions to switch specialties. The intention was not significantly associated with low residency satisfaction (OR, 1.7; 95%CI, 0.6-5.0), but was associated with low career satisfaction (OR, 5.1; 95%CI, 1.6-16.0). CONCLUSION: Improvements in training systems and stress reduction may increase residency and career satisfaction of emergency medicine residents, respectively. This study suggested that high career satisfaction was required to secure future emergency physicians.

BACKGROUND: Although the number of elderly increases disproportionately throughout the industrialised nations and intubation-related cardiovascular compromise is associated with hospital mortality, no emergency medicine literature has reported the direction and magnitude of effect of advanced age on post-intubation hypotension. We seek to determine whether advanced age is associated with an increased rate of hypotension at airway management in emergency departments (EDs). METHODS: We conducted an analysis of a multi-centre prospective observational study of 13 Japanese EDs from April 2010 to March 2012. Inclusion criteria were all adult non-cardiac-arrest patients who underwent emergency intubation. We excluded patients in whom airway management was performed for shock or status asthmaticus as the principal indication. Patients were divided into two groups defined a priori: age ≥ 65 years old (elderly group) and age < 65 years old (younger group). The primary outcome measure was post-intubation hypotension in the ED. RESULTS: During the 24-month period, 4,043 subjects required emergency airway management at 13 EDs. Among these, the database recorded 3,872 intubations (capture rate 96%). Of 1,903 eligible patients, 975 patients were age ≥ 65 years (51%) and 928 patients were age < 65 years (49%). The elderly group had a significantly higher rate of post-intubation hypotension compared with the younger group [3% vs. 1%; unadjusted OR 2.7 (95% CI, 1.3-5.6); P = 0.005]. In a model controlling for potential confounders (sex, principal indication, method, medication used to intubate, multiple intubation attempts), advanced age had an adjusted OR for post-intubation hypotension of 2.6 (95% CI, 1.3-5.6; P = 0.01). CONCLUSIONS: In this large multi-centre study of ED patients who underwent emergent airway management, we found that elderly patients have a significantly higher risk of post-intubation hypotension. These data provide implications for the education and practice of ED airway management that may lead to better clinical outcomes and improved patient safety.