Association of Psoas Muscle Mass at Intensive Care Unit Admission With Physical Function and Post-discharge Destination in Survivors of Critical Illness.

OBJECTIVE: Survivors of critical illness may have physical impairments, known as post-intensive care syndrome (PICS). Early screening for the risk of PICS is recommended to prevent PICS. Skeletal muscle mass is a clinically important indicator associated with various outcomes. This study aimed to examine the association of psoas muscle mass at intensive care unit (ICU) admission with the destination and physical function at hospital discharge. METHODS: In this single-center retrospective cohort study, we reviewed the medical records of adult patients who had required emergency ICU admission and who had been intubated and mechanically ventilated. Psoas major muscle was measured as an indicator of skeletal muscle mass from abdominal computed tomography images at ICU admission. Physical function was assessed using the functional status score for the ICU and ICU mobility scale at hospital discharge. Multinomial logistic and multivariable linear regression were used to analyze the associations of the psoas muscle mass with the discharge destination and physical function at discharge. RESULTS: We enrolled 124 patients (79 men and 45 women) with a median (interquartile range) age of 72.0 (62.0-80.0) years; 39 (31.5%) were discharged to home, 50 (40.3%) were transferred to rehabilitation wards, and 35 (28.2%) were transferred to long-term care settings. The psoas muscle area and volume were 16.9 (11.3-20.6) cm2 and 228.3 (180.2-282.0) cm3 in home discharge patients, 17.5 (11.5-21.5) cm2 and 248.4 (162.0-311.4) cm3 in rehabilitation ward patients, and 15.9 (10.3-19.5) cm2 and 184.0 (137.0-251.1) cm3 in long-term care patients. The areas and volumes of the psoas muscle were not significantly different in the three groups. Furthermore, psoas muscle mass was not significantly associated with the discharge destination and physical function. CONCLUSIONS: Discharge destination and physical function at hospital discharge were not significantly associated with psoas muscle mass at ICU admission.

External Validation of Updated Prediction Models for Neurological Outcomes at 90 Days in Patients With Out-of-Hospital Cardiac Arrest.

BACKGROUND: Few prediction models for individuals with early-stage out-of-hospital cardiac arrest (OHCA) have undergone external validation. This study aimed to externally validate updated prediction models for OHCA outcomes using a large nationwide dataset. METHODS AND RESULTS: We performed a secondary analysis of the JAAM-OHCA (Comprehensive Registry of In-Hospital Intensive Care for Out-of-Hospital Cardiac Arrest Survival and the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest) registry. Previously developed prediction models for patients with cardiac arrest who achieved the return of spontaneous circulation were updated. External validation was conducted using data from 56 institutions from the JAAM-OHCA registry. The primary outcome was a dichotomized 90-day cerebral performance category score. Two models were updated using the derivation set (n=3337). Model 1 included patient demographics, prehospital information, and the initial rhythm upon hospital admission; Model 2 included information obtained in the hospital immediately after the return of spontaneous circulation. In the validation set (n=4250), Models 1 and 2 exhibited a C-statistic of 0.945 (95% CI, 0.935-0.955) and 0.958 (95% CI, 0.951-0.960), respectively. Both models were well-calibrated to the observed outcomes. The decision curve analysis showed that Model 2 demonstrated higher net benefits at all risk thresholds than Model 1. A web-based calculator was developed to estimate the probability of poor outcomes (https://pcas-prediction.shinyapps.io/90d_lasso/). CONCLUSIONS: The updated models offer valuable information to medical professionals in the prediction of long-term neurological outcomes for patients with OHCA, potentially playing a vital role in clinical decision-making processes.

Non-linear association between the time required to reaching temperature targets and the neurological outcome in patients undergoing targeted temperature management after out-of-hospital cardiac arrest: Observational multicentre cohort study.

Purpose: We evaluated associations between outcomes and time to achieving temperature targets during targeted temperature management of out-of-hospital cardiac arrest. Methods: Using Comprehensive Registry of Intensive Care for out-of-hospital cardiac arrest Survival (CRITICAL) study, we enrolled all patients transported to participating hospitals from 1 July 2012 through 31 December 2017 aged ≥ 18 years with out-of-hospital cardiac arrest of cardiac aetiology and who received targeted temperature management in Osaka, Japan. Primary outcome was Cerebral Performance Category scale of 1 or 2 one month after cardiac arrest, designated as "one-month favourable neurological outcome". Non-linear multivariable logistic regression analyses assessed the primary outcome based on time to reaching temperature targets. In patients subdivided into quintiles based on time to achieving temperature targets, multivariable logistic regression calculated adjusted odds ratios and 95% confidence intervals. Results: We analysed 473 patients. In non-linear multivariable logistic regression analysis, p value for non-linearity was < 0.01. In the first quintile (< 26.7 minutes), second quintile (26.8-89.9 minutes), third quintile (90.0-175.1 minutes), fourth quintile (175.2-352.1 minutes), and fifth quintile (≥ 352.2 minutes), one-month favourable neurological outcome was 32.6% (31/95), 40.0% (36/90), 53.5% (53/99), 57.4% (54/94), and 37.9% (36/95), respectively. Adjusted odds ratios with 95% confidence intervals for one-month favourable neurological outcome in the first, second, third, and fifth quintiles compared with the fourth quintile were 0.38 (0.20 to 0.72), 0.43 (0.23 to 0.81), 0.77 (0.41 to 1.44), and 0.46 (0.25 to 0.87), respectively. Conclusion: Non-linear multivariable logistic regression analysis could clearly describe the association between neurological outcome in patients with out-of-hospital cardiac arrest and the time from the introduction of targeted temperature management to reaching the temperature targets.

In-hospital extracorporeal cardiopulmonary resuscitation for patients with out-of-hospital cardiac arrest: an analysis by time-dependent propensity score matching using a nationwide database in Japan.

BACKGROUND: Extracorporeal cardiopulmonary resuscitation (ECPR) has been proposed as a rescue therapy for patients with refractory cardiac arrest. This study aimed to evaluate the association between ECPR and clinical outcomes among patients with out-of-hospital cardiac arrest (OHCA) using risk-set matching with a time-dependent propensity score. METHODS: This was a secondary analysis of the JAAM-OHCA registry data, a nationwide multicenter prospective study of patients with OHCA, from June 2014 and December 2019, that included adults (≥ 18 years) with OHCA. Initial cardiac rhythm was classified as shockable and non-shockable. Patients who received ECPR were sequentially matched with the control, within the same time (minutes) based on time-dependent propensity scores calculated from potential confounders. The odds ratios with 95% confidence intervals (CI) for 30-day survival and 30-day favorable neurological outcomes were estimated for ECPR cases using a conditional logistic model. RESULTS: Of 57,754 patients in the JAAM-OHCA registry, we selected 1826 patients with an initial shockable rhythm (treated with ECPR, n = 913 and control, n = 913) and a cohort of 740 patients with an initial non-shockable rhythm (treated with ECPR, n = 370 and control, n = 370). In these matched cohorts, the odds ratio for 30-day survival in the ECPR group was 1.76 [95%CI 1.38-2.25] for shockable rhythm and 5.37 [95%CI 2.53-11.43] for non-shockable rhythm, compared to controls. For favorable neurological outcomes, the odds ratio in the ECPR group was 1.11 [95%CI 0.82-1.49] for shockable rhythm and 4.25 [95%CI 1.43-12.63] for non-shockable rhythm, compared to controls. CONCLUSION: ECPR was associated with increased 30-day survival in patients with OHCA with initial shockable and even non-shockable rhythms. Further research is warranted to investigate the reproducibility of the results and who is the best candidate for ECPR.

Recent Progress on Genetically Modified Animal Models for Membrane Skeletal Proteins: The 4.1 and MPP Families.

The protein 4.1 and membrane palmitoylated protein (MPP) families were originally found as components in the erythrocyte membrane skeletal protein complex, which helps maintain the stability of erythrocyte membranes by linking intramembranous proteins and meshwork structures composed of actin and spectrin under the membranes. Recently, it has been recognized that cells and tissues ubiquitously use this membrane skeletal system. Various intramembranous proteins, including adhesion molecules, ion channels, and receptors, have been shown to interact with the 4.1 and MPP families, regulating cellular and tissue dynamics by binding to intracellular signal transduction proteins. In this review, we focus on our previous studies regarding genetically modified animal models, especially on 4.1G, MPP6, and MPP2, to describe their functional roles in the peripheral nervous system, the central nervous system, the testis, and bone formation. As the membrane skeletal proteins are located at sites that receive signals from outside the cell and transduce signals inside the cell, it is necessary to elucidate their molecular interrelationships, which may broaden the understanding of cell and tissue functions.

Outcome assessment for out-of-hospital cardiac arrest patients in Singapore and Japan with initial shockable rhythm.

BACKGROUND: Singapore and Osaka in Japan have comparable population sizes and prehospital management; however, the frequency of ECPR differs greatly for out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythm. Given this disparity, we hypothesized that the outcomes among the OHCA patients with initial shockable rhythm in Singapore were different from those in Osaka. The aim of this study was to evaluate the outcomes of OHCA patients with initial shockable rhythm in Singapore compared to the expected outcomes derived from Osaka data using machine learning-based prediction models. METHODS: This was a secondary analysis of two OHCA databases: the Singapore PAROS database (SG-PAROS) and the Osaka-CRITICAL database from Osaka, Japan. This study included adult (18-74 years) OHCA patients with initial shockable rhythm. A machine learning-based prediction model was derived and validated using data from the Osaka-CRITICAL database (derivation data 2012-2017, validation data 2018-2019), and applied to the SG-PAROS database (2010-2016 data), to predict the risk-adjusted probability of favorable neurological outcomes. The observed and expected outcomes were compared using the observed-expected ratio (OE ratio) with 95% confidence intervals (CI). RESULTS: From the SG-PAROS database, 1,789 patients were included in the analysis. For OHCA patients who achieved return of spontaneous circulation (ROSC) on hospital arrival, the observed favorable neurological outcome was at the same level as expected (OE ratio: 0.905 [95%CI: 0.784-1.036]). On the other hand, for those who had continued cardiac arrest on hospital arrival, the outcomes were lower than expected (shockable rhythm on hospital arrival, OE ratio: 0.369 [95%CI: 0.258-0.499], and nonshockable rhythm, OE ratio: 0.137 [95%CI: 0.065-0.235]). CONCLUSION: This observational study found that the outcomes for patients with initial shockable rhythm but who did not obtain ROSC on hospital arrival in Singapore were lower than expected from Osaka. We hypothesize this is mainly due to differences in the use of ECPR.

Intra-Aortic Balloon Pump among Shockable Out-of-Hospital Cardiac Arrest Patients: A Propensity-Weighted Analysis in a Multicenter, Nationwide Observational Study in Japan (The JAAM-OHCA Registry).

BACKGROUND: The effectiveness of IABP for shockable out-of-hospital cardiac arrest (OHCA) has not been extensively investigated. This study aimed to investigate whether the use of an intra-aortic balloon pump (IABP) for non-traumatic shockable OHCA patients was associated with favorable neurological outcomes. METHODS: From the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry, a nationwide multicenter prospective registry, we enrolled adult patients with non-traumatic and shockable OHCA for whom resuscitation was attempted, and who were transported to participating hospitals between 2014 and 2019. The primary outcome was 1-month survival with favorable neurological outcomes after OHCA. After adopting the propensity score (PS) inverse probability of weighting (IPW), we evaluated the association between IABP and favorable neurological outcomes. RESULTS: Of 57,754 patients in the database, we included a total of 2738 adult non-traumatic shockable patients. In the original cohort, the primary outcome was lower in the IABP group (OR with 95% confidence intervals (CIs)), 0.57 (0.48-0.68), whereas, in the IPW cohort, it was not different between patients with and without IABP (OR, 1.18; 95% CI, 0.91-1.53). CONCLUSION: In adult patients with non-traumatic shockable OHCA, IABP use was not associated with 1-month survival with favorable neurological outcomes.

Ultrasound stimulation of the vagal nerve improves acute septic encephalopathy in mice.

Septic encephalopathy (SE) is characterized by symptoms such as coma, delirium, and cognitive dysfunction, and effective therapeutic interventions for SE remain elusive. In this study, we aimed to investigate the potential alleviating effects of vagal nerve stimulation (VNS) on SE-associated signs. To evaluate our hypothesis, we utilized a mouse model of SE induced by intraperitoneal injection of lipopolysaccharide (0.3 mg per mouse) and administered noninvasive, high-frequency ultrasound VNS. To assess the efficacy of ultrasound VNS, we measured inflammation-related molecules, including the α7 nicotinic acetylcholine receptor (α7nAChR) expression in peritoneal macrophages and plasma interleukin 1ß (IL-1ß) levels. Consistent with our hypothesis, SE mice exhibited reduced α7nAChR expression in macrophages and elevated IL-1ß levels in the blood. Remarkably, VNS in SE mice restored α7nAChR expression and IL-1ß levels to those observed in control mice. Furthermore, we evaluated the effects of VNS on survival rate, body temperature, and locomotor activity. SE mice subjected to VNS demonstrated a modest, yet significant, improvement in survival rate, recovery from hypothermia, and increased locomotor activity. To investigate the impact on the brain, we examined the hippocampus of SE mice. In control mice, VNS increased the expression of c-fos, a marker of neuronal electrical excitability, in the hippocampus. In SE mice, VNS led to the restoration of aberrant firing patterns in hippocampal neurons. Additionally, proteomic analysis of hippocampal tissue in SE mice revealed abnormal increases in two proteins, tissue factor (TF) and acyl-CoA dehydrogenase family member 9 (ACAD9), which returned to control levels following VNS. Collectively, our findings support the value of exploring the beneficial effects of ultrasound VNS on SE.

Diagnostic test accuracy of life-threatening electrocardiographic findings (ST-elevation myocardial infarction equivalents) for acute coronary syndrome after out-of-hospital cardiac arrest without ST-segment elevation.

AIM: Life-threatening electrocardiographic (ECG) findings aid in the diagnosis of acute coronary syndrome (ACS), which has not been well-evaluated in patients with out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate the diagnostic test accuracy (DTA) of ST-elevation myocardial infarction (STEMI) equivalents following the return of spontaneous circulation (ROSC) in patients with OHCA to identify patients with ACS. METHODS: Using the database of the Comprehensive Registry of In-Hospital Intensive Care for OHCA Survival study from 2012 to 2017, patients aged ≥18 years with non-traumatic OHCA and ventricular fibrillation or pulseless ventricular tachycardia on the arrival of emergency medical service personnel or arrival at the emergency department, who achieved ROSC, were included. Patients without ST-segment elevation or complete left bundle branch block on ECG and those who did not undergo ECG or coronary angiography, were excluded from the study. We evaluated the DTA of STEMI equivalents for the diagnosis of ACS: isolated T-wave inversion, ST-segment depression, Wellens' signs, and ST-segment elevation in lead aVR. RESULTS: Isolated T-wave inversion and Wellens' signs had high specificity for ACS with 0.95 (95% confidence interval [CI], 0.87-0.99) and 0.92 (95% CI, 0.82-0.97), respectively, but their positive likelihood ratios were low, with a wide range of 95% CI: 1.89 (95% CI, 0.51-7.02) and 0.81 (95% CI, 0.25-2.68), respectively. CONCLUSION: The DTA of STEMI equivalents for the diagnosis of ACS was low among patients with OHCA. Further investigation considering the measurement timing of the ECG after ROSC is required.

External validation of the TiPS65 score for predicting good neurological outcomes in patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation.

AIM: Estimating prognosis of patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) is essential for selecting candidates. The TiPS65 score can predict neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) treated with ECPR. We aimed to perform an external validation of this score. METHODS: Data from the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry, a multicentred, nationwide, prospectively registered database, were analysed. All adult patients with OHCA and shockable rhythm and treated with ECPR between January 2018 to December 2019 were included. In the TiPS65 score, age, call-to-hospital arrival time, initial cardiac rhythm at hospital arrival, and initial pH value were used as predictors. The primary outcome was 30-day survival with favourable neurological outcomes (Cerebral Performance Category 1 or 2). Discrimination, using the C-statistic, and predictive performances of each score, such as sensitivity and specificity, were investigated. RESULTS: Of 590 included patients (517 [81.6%] men; median [interquartile range] age, 60 [50-69] years), 64 (10.8%) reported favourable neurological outcomes. The C-statistic of the TiPS65 score was 0.729 (95% confidence interval (CI): 0.672-0.786). When the cut-off of TiPS65 score was set to >1, the sensitivity and specificity were 0.906 (95%CI: 0.807-0.965) and 0.430 (95%CI: 0.387-0.473), respectively; conversely, when the cut-off was set to >3, they were 0.172 (95%CI: 0.089-0.287) and 0.971 (95%CI: 0.953-0.984), respectively. CONCLUSIONS: The TiPS65 score shows reasonable discrimination and predictive performances. This score can be supportive in the decision-making process for the selection of eligible patients for ECPR in clinical settings.

Association between blood urea nitrogen to creatinine ratio and neurologically favourable outcomes in out-of-hospital cardiac arrest in adults: A multicentre cohort study.

BACKGROUND: We aimed to investigate the association between blood urea nitrogen to creatinine ratio (BCR) and survival with favourable neurological outcomes in patients with out-of-hospital cardiac arrest (OHCA). METHODS: This prospective, multicentre, observational study conducted in Osaka, Japan enrolled consecutive OHCA patients transported to 16 participating institutions from 2012 through 2019. We included adult patients with non-traumatic OHCA who achieved a return of spontaneous circulation and whose blood urea nitrogen and creatinine levels on hospital arrival were available. Based on BCR values, they were divided into: 'low BCR' (BCR <10), 'normal BCR' (10 ≤ BCR < 20), 'high BCR' (20 ≤ BCR < 30), and 'very high BCR' (BCR ≥ 30). We evaluated the association between BCR values and neurologically favourable outcomes, defined as cerebral performance category score of 1 or 2 at one month after OHCA. RESULTS: Among 4415 eligible patients, the 'normal BCR' group had the highest favourable neurological outcome [19.4 % (461/2372)], followed by 'high BCR' [12.5 % (141/1127)], 'low BCR' [11.2 % (50/445)], and 'very high BCR' groups [6.6 % (31/471)]. In the multivariable analysis, adjusted odds ratios for 'low BCR', 'high BCR', and 'very high BCR' compared with 'normal BCR' for favourable neurological outcomes were 0.58 [95 % confidence interval (CI 0.37-0.91)], 0.70 (95 % CI 0.49-0.99), and 0.40 (95 % CI 0.21-0.76), respectively. Cubic spline analysis indicated that the association between BCR and favourable neurological outcomes was non-linear (p for non-linearity = 0.003). In subgroup analysis, there was an interaction between the aetiology of arrest and BCR in neurological outcome (p for interaction <0.001); favourable neurological outcome of cardiogenic OHCA patients was lower when the BCR was higher or lower, but not in non-cardiogenic OHCA patients. CONCLUSIONS: Both higher and lower BCR were associated with poor neurological outcomes compared to normal BCR, especially in cardiogenic OHCA patients.

Involvement of membrane palmitoylated protein 2 (MPP2) in the synaptic molecular complex at the mouse cerebellar glomerulus.

We previously reported that the membrane skeletal protein 4.1G in the peripheral nervous system transports membrane palmitoylated protein 6 (MPP6), which interacts with the synaptic scaffolding protein Lin7 and cell adhesion molecule 4 (CADM4) in Schwann cells that form myelin. In the present study, we investigated the localization of and proteins related to MPP2, a highly homologous family protein of MPP6, in the cerebellum of the mouse central nervous system, in which neurons are well organized. Immunostaining for MPP2 was observed at cerebellar glomeruli (CG) in the granular layer after postnatal day 14. Using the high-resolution Airyscan mode of a confocal laser-scanning microscope, MPP2 was detected as a dot pattern and colocalized with CADM1 and Lin7, recognized as small ring/line patterns, as well as with calcium/calmodulin-dependent serine protein kinase (CASK), NMDA glutamate receptor 1 (GluN1), and M-cadherin, recognized as dot patterns, indicating the localization of MPP2 in the excitatory postsynaptic region and adherens junctions of granule cells. An immunoprecipitation analysis revealed that MPP2 formed a molecular complex with CADM1, CASK, M-cadherin, and Lin7. Furthermore, the Lin7 staining pattern showed small rings surrounding mossy fibers in wild-type CG, while it changed to the dot/spot pattern inside small rings detected with CADM1 staining in MPP2-deficient CG. These results indicate that MPP2 influences the distribution of Lin7 to synaptic cell membranes at postsynaptic regions in granule cells at CG, at which electric signals enter the cerebellum.

Clustering out-of-hospital cardiac arrest patients with non-shockable rhythm by machine learning latent class analysis.

Aim: We aimed to identify subphenotypes among patients with out-of-hospital cardiac arrest (OHCA) with initial non-shockable rhythm by applying machine learning latent class analysis and examining the associations between subphenotypes and neurological outcomes. Methods: This study was a retrospective analysis within a multi-institutional prospective observational cohort study of OHCA patients in Osaka, Japan (the CRITICAL study). The data of adult OHCA patients with medical causes and initial non-shockable rhythm presenting with OHCA between 2012 and 2016 were included in machine learning latent class analysis models, which identified subphenotypes, and patients who presented in 2017 were included in a dataset validating the subphenotypes. We investigated associations between subphenotypes and 30-day neurological outcomes. Results: Among the 12,594 patients in the CRITICAL study database, 4,849 were included in the dataset used to classify subphenotypes (median age: 75 years, 60.2% male), and 1,465 were included in the validation dataset (median age: 76 years, 59.0% male). Latent class analysis identified four subphenotypes. Odds ratios and 95% confidence intervals for a favorable 30-day neurological outcome among patients with these subphenotypes, using group 4 for comparison, were as follows; group 1, 0.01 (0.001-0.046); group 2, 0.097 (0.051-0.171); and group 3, 0.175 (0.073-0.358). Associations between subphenotypes and 30-day neurological outcomes were validated using the validation dataset. Conclusion: We identified four subphenotypes of OHCA patients with initial non-shockable rhythm. These patient subgroups presented with different characteristics associated with 30-day survival and neurological outcomes.

Clinical outcomes among out-of-hospital cardiac arrest patients treated by extracorporeal cardiopulmonary resuscitation: The CRITICAL study in Osaka.

AIM: Extracorporeal cardiopulmonary resuscitation (ECPR) is performed in refractory out-of-hospital cardiac arrest (OHCA) patients, and the eligibility has been conventionally determined based on three criteria (initial cardiac rhythm, time to hospital arrival within 45 minutes, and age <75 years) in Japan. Owing to limited information, this study descriptively determined neurological outcomes after applying the three criteria among OHCA patients who underwent ECPR. METHODS: This study conducted a post-hoc analysis of data from the Comprehensive Registry of Intensive Care for OHCA Survival (CRITICAL) study. This was a multi-institutional prospective observational study of OHCA patients in Osaka Prefecture, Japan. All adult (aged ≥18 years) OHCA patients with internal medical causes treated with ECPR between 1 July 2012 and 31 December 2019 were evaluated. We described one-month neurological favourable outcomes based on the three criteria (initial shockable, time to hospital arrival within 45 minutes, and age <75 years), and we compared them using the chi-square test. RESULTS: Among 18,379 patients screened from the CRITICAL study database, we included 517 OHCA patients treated by ECPR; 311 (60.2%) patients met all three criteria. Favourable neurological outcomes were as follows: patients meeting no or one criterion: 2.3% (1/43), those meeting two criteria: 8% (13/163), and those meeting all criteria: 16.1% (50/311) (P-value = 0.004). CONCLUSIONS: In this study, approximately 60% of patients treated by ECPR met the three criteria (initial shockable, time to hospital arrival within 45 minutes, and age <75 years), and the greater the number of criteria met, the better were the neurological outcomes achieved.

Association between initial body temperature on hospital arrival and neurological outcome among patients with out-of-hospital cardiac arrest: a multicenter cohort study (the CRITICAL study in Osaka, Japan).

BACKGROUND: The association between spontaneous initial body temperature on hospital arrival and neurological outcomes has not been sufficiently studied in patients after out-of-hospital cardiac arrest (OHCA). METHODS: From the prospective database of the Comprehensive Registry of Intensive Care for OHCA Survival (CRITICAL) study in Osaka, Japan, we enrolled all patients with OHCA of medical origin aged > 18 years for whom resuscitation was attempted and who were transported to participating hospitals between 2012 and 2019. We excluded patients who were not witnessed by bystanders and treated by a doctor car or helicopter, which is a car/helicopter with a physician. The patients were categorized into three groups according to their temperature on hospital arrival: ≤35.9 °C, 36.0-36.9 °C (normothermia), and ≥ 37.0 °C. The primary outcome was 1-month survival, with a cerebral performance category of 1 or 2. Multivariable logistic regression analyses were performed to evaluate the association between temperature and outcomes (normothermia was used as the reference). We also assessed this association using cubic spline regression analysis. RESULTS: Of the 18,379 patients in our database, 5014 witnessed adult OHCA patients of medical origin from 16 hospitals were included. When analyzing 3318 patients, OHCA patients with an initial body temperature of ≥37.0 °C upon hospital arrival were associated with decreased favorable neurological outcomes (6.6% [19/286] odds ratio, 0.51; 95% confidence interval, 0.27-0.95) compared to patients with normothermia (16.4% [180/1100]), whereas those with an initial body temperature of ≤35.9 °C were not associated with decreased favorable neurological outcomes (11.1% [214/1932]; odds ratio, 0.78; 95% confidence interval, 0.56-1.07). The cubic regression splines demonstrated that a higher body temperature on arrival was associated with decreased favorable neurological outcomes, and a lower body temperature was not associated with decreased favorable neurological outcomes. CONCLUSIONS: In adult patients with OHCA of medical origin, a higher body temperature on arrival was associated with decreased favorable neurologic outcomes.

Early prognostic impact of serum sodium level among out-of-hospital cardiac arrest patients: a nationwide multicentre observational study in Japan (the JAAM-OHCA registry).

Dysnatremia is an electrolytic disorder commonly associated with mortality in various diseases. However, little is known about dysnatremia in out-of-hospital cardiac arrest (OHCA) cases. Here, we investigated the association between serum sodium level on hospital arrival and neurological outcomes after OHCA. This nationwide hospital-based observational study (The Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry) enrolled patients with OHCA between 2014 and 2017. We included adult patients aged ≥ 18 years with non-traumatic OHCA who achieved return of spontaneous circulation (ROSC) and whose serum sodium level on hospital arrival was available. Based on the serum sodium level, patients were divided into three levels: hyponatremia (Na < 135 mEq/L), normal sodium level (Na ≥ 135 or ≤ 145 mEq/L), and hypernatremia (Na > 145 mEq/L). The primary outcome was 1-month survival with favourable neurological outcomes. Altogether, 34 754 patients with OHCA were documented, and 5160 patients with non-traumatic OHCA and who achieved ROSC were eligible for our analyses. The proportion of favourable neurological outcomes was highest in patients with normal sodium levels at 17.6% (677/3854), followed by patients with hyponatremia at 8.2% (57/696) and patients with hypernatremia at 5.7% (35/610). Moreover, hyponatremia and hypernatremia were associated with a decreased probability of favourable neurological outcomes compared with normal sodium level (vs. hyponatremia, adjusted odds ratio [AOR] 0.97, 95% confidence interval [CI] 0.95-0.99; vs. hypernatremia, AOR 0.96, 95% CI 0.94-0.98). Hypo- and hypernatremia on hospital arrival were associated with a decreased probability of favourable neurological outcomes in patients with non-traumatic OHCA who achieved ROSC.

Clinical Phenotyping of Out-of-Hospital Cardiac Arrest Patients With Shockable Rhythm　- Machine Learning-Based Unsupervised Cluster Analysis.

BACKGROUND: The hypothesis of this study is that latent class analysis could identify the subphenotypes of out-of-hospital cardiac arrest (OHCA) patients associated with the outcomes and allow us to explore heterogeneity in the effects of extracorporeal cardiopulmonary resuscitation (ECPR).Methods and Results:This study was a retrospective analysis of a multicenter prospective observational study (CRITICAL study) of OHCA patients. It included adult OHCA patients with initial shockable rhythm. Patients from 2012 to 2016 (development dataset) were included in the latent class analysis, and those from 2017 (validation dataset) were included for evaluation. The association between subphenotypes and outcomes was investigated. Further, the heterogeneity of the association between ECPR implementation and outcomes was explored. In the study results, a total of 920 patients were included for latent class analysis. Three subphenotypes (Groups 1, 2, and 3) were identified, mainly characterized by the distribution of partial pressure of O2(PO2), partial pressure of CO2(PCO2) value of blood gas assessment, cardiac rhythm on hospital arrival, and estimated glomerular filtration rate. The 30-day survival outcomes were varied across the groups: 15.7% in Group 1; 30.7% in Group 2; and 85.9% in Group 3. Further, the association between ECPR and 30-day survival outcomes by subphenotype groups in the development dataset was as varied. These results were validated using the validation dataset. CONCLUSIONS: The latent class analysis identified 3 subphenotypes with different survival outcomes and potential heterogeneity in the effects of ECPR.

Prompt Reduction in CRP, IL-6, IFN-γ, IP-10, and MCP-1 and a Relatively Low Basal Ratio of Ferritin/CRP Is Possibly Associated With the Efficacy of Tocilizumab Monotherapy in Severely to Critically Ill Patients With COVID-19.

Background and Aim: Tocilizumab, a humanized anti-IL-6 receptor antibody, has been used to treat severely to critically ill patients with COVID-19. A living systematic review with meta-analysis of recent RCTs indicates that the combination therapy of corticosteroids and tocilizumab produce better outcomes, while previous observational studies suggest that tocilizumab monotherapy is beneficial for substantial numbers of patients. However, what patients could respond to tocilizumab monotherapy remained unknown. Methods: In this retrospective study we evaluated the effects of tocilizumab monotherapy on the clinical characteristics, serum biomediator levels, viral elimination, and specific IgG antibody induction in 13 severely to critically ill patients and compared with those of dexamethasone monotherapy and dexamethasone plus tocilizumab. Results: A single tocilizumab administration led to a rapid improvement in clinical characteristics, inflammatory findings, and oxygen supply in 7 of 11 patients with severe COVID-19, and could recover from mechanical ventilation management (MVM) in 2 patients with critically ill COVID-19. Four patients exhibited rapidly worsening even after tocilizumab administration and required MVM and additional methylprednisolone treatment. Tocilizumab did not delay viral elimination or inhibit IgG production specific for the virus, whereas dexamethasone inhibited IgG induction. A multiplex cytokine array system revealed a significant increase in the serum expression of 54 out of 80 biomediators in patients with COVID-19 compared with that in healthy controls. Compared with those who promptly recovered in response to tocilizumab, patients requiring MVM showed a significantly higher ratio of basal level of ferritin/CRP and a persistent increase in the levels of CRP and specific cytokines and chemokines including IL-6, IFN-γ, IP-10, and MCP-1. The basal high ratio of ferritin/CRP was also associated with clinical deterioration even in patients treated with dexamethasone and tocilizumab. Conclusion: Tocilizumab as monotherapy has substantial beneficial effects in some patients with severe COVID-19, who showed a relatively low level of the ratio of ferritin/CRP and prompt reduction in CRP, IL-6, IFN-γ, IP-10, and MCP-1. The high ratio of ferritin/CRP is associated with rapid worsening of pneumonia. Further evaluation is warranted to clarify whether tocilizumab monotherapy or its combination with corticosteroid is preferred for severely to critically ill patients with COVID-19.