Rapid mortality in captive bush dogs (Speothos venaticus) caused by influenza A of avian origin (H5N1) at a wildlife collection in the United Kingdom.

Europe has suffered unprecedented epizootics of high pathogenicity avian influenza (HPAI) clade 2.3.4.4b H5N1 since Autumn 2021. As well as impacting upon commercial and wild avian species, the virus has also infected mammalian species more than ever observed previously. Mammalian species involved in spill over events have primarily been scavenging terrestrial carnivores and farmed mammalian species although marine mammals have also been affected. Alongside reports of detections of mammalian species found dead through different surveillance schemes, several mass mortality events have been reported in farmed and wild animals. In November 2022, an unusual mortality event was reported in captive bush dogs (Speothos venaticus) with clade 2.3.4.4b H5N1 HPAIV of avian origin being the causative agent. The event involved an enclosure of 15 bush dogs, 10 of which succumbed during a nine-day period with some dogs exhibiting neurological disease. Ingestion of infected meat is proposed as the most likely infection route.

Measuring concordance and discordance between selected individual characteristics and corresponding neighborhood-level social determinants of health.

Background: Individuals reside within communities influenced by various social determinants impacting health, which may harmonize or conflict at individual and neighborhood levels. While some experience concordant circumstances, discordance is prevalent, yet poorly understood due to the lack of a universally accepted method for quantifying it. This paper proposes a methodology to address this gap. Methods: We propose a systematic approach to operationalize concordance and discordance between individual and neighborhood social determinants, using household income (HHI) (continuous) and race/ethnicity (categorical) as examples for individual social determinants. We demonstrated our method with a small dataset that combines self-reported individual data with geocoded neighborhood level. We anticipate that the risk profiles created by either self-reported individual data or neighborhood-level data alone will differ from patterns demonstrated by typologies based on concordance and discordance. Results: In our cohort, it was revealed that 20% of patients experienced discordance between their HHIs and neighborhood characteristics. Additionally, 38% reside in racially/ethnically concordant neighborhoods, 23% in discordant ones, and 39% in neutral ones. Conclusion: Our study introduces an innovative approach to defining and quantifying the notions of concordance and discordance in individual attributes concerning neighborhood-level social determinants. It equips researchers with a valuable tool to conduct more comprehensive investigations into the intricate interplay between individuals and their environments. Ultimately, this methodology facilitates a more accurate modeling of the true impacts of social determinants on health, contributing to a deeper understanding of this complex relationship.

The Association of Racial Residential Segregation and Survival After Out-of-Hospital Cardiac Arrest in the United States.

Background: Residential segregation has been identified as drivers of disparities in health outcomes, but further work is needed to understand this association with clinical outcomes for out-of-hospital cardiac arrest (OHCA). We utilized Cardiac Arrest Registry to Enhance Survival (CARES) dataset to examine if there are differences in survival to discharge and survival with good neurological outcome, as well as likelihood of bystander CPR, using validated measures of racial, ethnic, and economic segregation. Methods: We conducted a retrospective observational study using data from the Cardiac Arrest Registry to Enhance Survival (CARES) dataset to examine associations among adult OHCA patients. The primary predictor was the Index of Concentration at the Extremes (ICE), a validated measure that includes race, ethnicity, and income across three measures at the census tract level. The primary outcomes were survival to discharge and survival with good neurological status. A multivariable modified Poisson regression modeling approach with random effects at the EMS agency and hospital level was utilized. Results: We identified 626,264 OHCA patients during the study period. The mean age was 62 years old (SD 17.2 years), and 35.7% (n =223,839) of the patients were female. In multivariable models, we observed an increased likelihood of survival to discharge and survival with good neurological outcome for those patients residing in predominately White population census tracts and higher income census tracts as compared to lower income Black and Hispanic/Latinx population census tracts (RR 1.24, CI 1.20-1.28) and a 32% increased likelihood of receiving bystander CPR in higher income census tracts as compared to reference (RR 1.32, CI 1.30-1.34). Conclusions: In this study examining the association of measures of residential segregation and OHCA outcomes, there was an increased likelihood of survival to discharge, survival with good neurological status, and likelihood of receiving B-CPR for those patients residing in predominately White population and higher income census tracts when compared to predominately Black and/or Hispanic Latinx populations and lower income census tracts. This research suggests that areas impacted by residential and economic segregation are important targets for both public policy interventions as well as addressing disparities in care across the chain of survival for OHCA.

Patient Factors Associated With Prolonged Length of Stay After Traumatic Brain Injury.

Background For traumatic brain injury (TBI) survivors, recovery can lead to significant time spent in the inpatient/rehabilitation settings. Hospital length of stay (LOS) after TBI is a crucial metric of resource utilization and treatment costs. Risk factors for prolonged LOS (PLOS) after TBI require further characterization. Methodology We conducted a retrospective analysis of patients with diagnosed TBI at an urban trauma center. PLOS was defined as the 95th percentile of the LOS of the cohort. Patients with and without PLOS were compared using clinical/injury factors. Analyses included descriptive statistics, non-parametric analyses, and multivariable logistic regression for PLOS status. Results The threshold for PLOS was >24 days. In the cohort of 1,343 patients, 77 had PLOS. PLOS was significantly associated with longer mean intensive care unit (ICU) stays (16.4 vs. 1.5 days), higher mean injury severity scores (18.6 vs. 13.8), lower mean Glasgow coma scale scores (11.3 vs. 13.7) and greater mean complication burden (0.7 vs. 0.1). PLOS patients were more likely to have moderate/severe TBI, Medicaid insurance, and were less likely to be discharged home. In the regression model, PLOS was associated with ICU stay, inpatient disposition, ventilator use, unplanned intubation, and inpatient alcohol withdrawal. Conclusions TBI patients with PLOS were more likely to have severe injuries, in-hospital complications, and Medicaid insurance. PLOS was predicted by ICU stay, intubation, alcohol withdrawal, and disposition to inpatient/post-acute care facilities. Efforts to reduce in-hospital complications and expedite discharge may reduce LOS and accompanying costs. Further validation of these results is needed from larger multicenter studies.

Stage B Heart Failure Is Ubiquitous in Emergency Patients with Asymptomatic Hypertension.

Introduction: Hypertension is the leading risk factor for morbidity and mortality throughout the world and is pervasive in United States emergency departments (ED). This study documents the point prevalence of subclinical heart disease in emergency patients with asymptomatic hypertension. Method: This was a prospective observational study of ED patients with asymptomatic hypertension conducted at two urban academic EDs that belong to an eight-hospital healthcare organization in New York. Adult (≥18 years of age) English- or Spanish-speaking patients who had an initial blood pressure (BP) ≥160/100 millimeters of mercury (mmHg) and second BP ≥140/90 mm Hg, and pending discharge, were invited to participate in the study. We excluded patients with congestive heart failure, renal insufficiency, and atrial fibrillation, or who were pregnant, a prisoner, cognitively unable to provide informed consent, or experiencing symptoms of hypertension. We assessed echocardiographic evidence of subclinical heart disease (left ventricular hypertrophy, and diastolic and systolic dysfunction). Results: A total of 53 patients were included in the study; a majority were young (mean 49.5 years old, [SD 14-52]), self-identified as Black or Other (n = 39; 73.5%), and female (n = 30; 56.6%). Mean initial blood pressure was 172/100 mm Hg, and 24 patients (45.3%) self-reported a history of hypertension. Fifty patients completed an echocardiogram. All (100%) had evidence of subclinical heart disease, with 41 (77.4%) displaying left ventricular hypertrophy and 31 (58.5%) diastolic dysfunction. There was a significant relationship between diastolic dysfunction and female gender [x2 (1, n = 53) = 3.98; P = 0.046]; Black or other race [x2 (3, n = 53) = 9.138; P = 0.03] and Hispanic or other ethnicity [x2 (2, n = 53) = 8.03; P = 0.02]. Less than one third of patients demonstrated systolic dysfunction on echocardiogram, and this was more likely to occur in patients with diabetes mellitus [x2 (1, n = 51) = 4.84; P = 0.02]. Conclusion: There is a high probability that Black, Hispanic, and female patients with asymptomatic hypertension are on the continuum for developing overt heart failure. Emergency clinicians should provide individualized care that considers their unique health needs, cultural backgrounds, and social determinants of health.

Association between Estrogen Exposure and Idiopathic Subglottic Stenosis.

OBJECTIVE: Idiopathic subglottic stenosis (iSGS) is a rare, recurrent, fibroinflammatory disease affecting the larynx and proximal trachea. Given it occurs primarily in adult females, estrogen is speculated to play a central pathophysiological role. This study aimed to evaluate relationships between estrogen exposure, disease progression, and recurrence. METHODS: North American Airway Collaborative (NoAAC) data of adults with iSGS obstructive airway lesions, who underwent index endoscopic airway dilation, were used to identify associations between estrogen exposure, disease characteristics, and time to recurrence (TTR), and interventions were analyzed using Kruskal-Wallis test and Pearson coefficient. Cox proportional hazards regression models compared hazard ratios by estrogen exposure. Kaplan-Meier curves were plotted for TTR based on menopausal status. RESULTS: In all, 533 females had complete estrogen data (33% premenopausal, 17% perimenopausal, 50% postmenopausal). Median estrogen exposure was 28 years. Overall, there was no dose-response relationship between estrogen exposure and disease recurrence. Premenopausal patients had significantly shorter time from symptom manifestation to diagnosis (1.17 vs. 1.42 years perimenopausal vs. 2.08 years postmenopausal, p < 0.001), shorter time from diagnosis to index endoscopic airway dilation (1.90 vs. 2.50 vs. 3.76 years, p = 0.005), and higher number of procedures (1.73 vs. 1.20 vs. 1.08 procedures, p < 0.001). CONCLUSIONS: We demonstrate premenopausal patients may have a more aggressive disease variant than their peri- and postmenopausal counterparts. However, it is unclear as to whether this is related to reduced estrogen in the peri- and postmenopausal states or the age-related physiology of wound healing and inflammation, regardless of estrogen. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:825-830, 2024.

"The project did not come to us with a solution": Perspectives of research teams on implementing a study about electronic health record-embedded individualized pain plans for emergency department treatment of vaso-occlusive episodes in adults with sickle cell disease.

BACKGROUND: This study aimed to capture the implementation process of the ALIGN Study, (An individualized Pain Plan with Patient and Provider Access for Emergency Department care of Sickle Cell Disease). ALIGN aimed to embed Individualized Pain Plans in the electronic health record (E-IPP) and provide access to the plan for both adult patients with sickle cell disease (SCD) and emergency department providers when a person with SCD comes to the emergency department in vaso-occlusive crises. METHODS: Semi-structured interviews were conducted with research teams from the 8 participating sites from the ALIGN study. Seventeen participants (principal investigators and study coordinators) shared their perspectives about the implementation of ALIGN in their sites. Data were analyzed in three phases using open coding steps adapted from grounded theory and qualitative content analysis. RESULTS: A total of seven overarching themes were identified: (1) the E-IPP structure (location and upkeep) and collaboration with the informatics team, (2) the role of ED champion, (3) the role of research coordinators, (4) research team communication, and communication between research team and clinical team, (5) challenges with the study protocol, (6) provider feedback: addressing over-utilizers, patient mistrust, and the positive feedback about the intervention, and (7) COVID-19 and its effects on study implementation. CONCLUSIONS: Findings from this study contribute to learning how to implement E-IPPs for adult patients with SCD in ED. The study findings highlight the importance of early engagement with different team members, a champion from the emergency department, study coordinators with different skills and enhancement of communication and trust among team members. Further recommendations are outlined for hospitals aiming to implement E-IPP for patients with SCD in ED.

The competition between anthropogenic aerosol and greenhouse gas climate forcing is revealed by North Pacific water-mass changes.

Modeled water-mass changes in the North Pacific thermocline, both in the subsurface and at the surface, reveal the impact of the competition between anthropogenic aerosols (AAs) and greenhouse gases (GHGs) over the past 6 decades. The AA effect overwhelms the GHG effect during 1950-1985 in driving salinity changes on density surfaces, while after 1985 the GHG effect dominates. These subsurface water-mass changes are traced back to changes at the surface, of which ~70% stems from the migration of density surface outcrops, equatorward due to regional cooling by AAs and subsequent poleward due to warming by GHGs. Ocean subduction connects these surface outcrop changes to the main thermocline. Both observations and models reveal this transition in climate forcing around 1985 and highlight the important role of AA climate forcing on our oceans' water masses.

Association of Racial Residential Segregation With Long-Term Outcomes and Readmissions After Out-of-Hospital Cardiac Arrest Among Medicare Beneficiaries.

Background The national impact of racial residential segregation on out-of-hospital cardiac arrest outcomes after initial resuscitation remains poorly understood. We sought to characterize the association between measures of racial and economic residential segregation at the ZIP code level and long-term survival and readmissions after out-of-hospital cardiac arrest among Medicare beneficiaries. Methods and Results In this retrospective cohort study, using Medicare claims data, our primary predictor was the index of concentration at the extremes, a measure of racial and economic segregation. The primary outcomes were death up to 3 years and readmissions. We estimated hazard ratios (HRs) across all 3 types of index of concentration at the extremes measures for each outcome while adjusting for beneficiary demographics, treating hospital characteristics, and index hospital procedures. In fully adjusted models for long-term survival, we found a decreased hazard of death and risk of readmission for beneficiaries residing in the more segregated White communities  and higher-income ZIP codes compared with the more segregated Black communities and lower-income ZIP codes across all 3 indices of concentration at the extremes measures (race: HR, 0.87 [95% CI, 0.81-0.93]; income: HR, 0.75 [95% CI, 0.69-0.78]; and race+income: HR, 0.77 [95% CI, 0.72-0.82]). Conclusions We found a decreased hazard of death and risk for readmission for those residing in the more segregated White communities  and higher-income ZIP codes compared with the more segregated Black communities and lower-income ZIP codes when using validated measures of racial and economic segregation. Although causal pathways and mechanisms remain unclear, disparities in outcomes after out-of-hospital cardiac arrest are associated with the structural components of race and wealth and persist up to 3 years after discharge.

Designing a Road Map for Action to Address Bias and Racism Within a Large Academic Medical Center.

ABSTRACT: The convergence of the COVID-19 pandemic, the Black Lives Matter Movement, and the public anguish and outrage resulting from the murder of George Floyd in 2020 intensified the commitment of many health care institutions to pursue racial and social justice and achieve health equity. The authors describe the Road Map for Action to Address Racism, which was developed to unify and systematize antiracism efforts across the Mount Sinai Health System. A 51-member Task Force to Address Racism, comprising faculty, staff, students, alumni, health system leaders, and trustees, developed recommendations to achieve the goal of becoming an antiracist and equitable health care and learning institution by intentionally addressing all forms of racism and promoting greater diversity, inclusion, and equity for its workforce and community. Grounded in the principles of Collective Impact, the Task Force developed a set of 11 key strategies to effect systemwide change. The strategies affected all aspects of the organization: business systems and financial operations, delivery of care, workforce development and training, leadership development, medical education, and community engagement. The authors describe Road Map implementation, currently in process, including the appointment of strategy leaders, evolution of a governance structure integrating stakeholders from across the health system, development of an evaluation framework, communication and engagement efforts, and process measures and progress to date. Lessons learned include the importance of recognizing the work of dismantling racism as integral to, not apart from, the institution's day-to-day work, and the need for specialized expertise and a significant investment of time to coordinate Road Map implementation. Going forward, rigorous assessment of quantitative and qualitative outcomes and a commitment to sharing successes and challenges will be critical to eradicating systems that have perpetuated inequities in the biomedical sciences and medicine and in the delivery of health care.

Emergency Physician Observations and Attitudes on Law Enforcement Activities in the Emergency Department.

INTRODUCTION: Law enforcement officers (LEO) interact with patients and clinicians in the emergency department (ED) for many reasons. There is no current consensus on what should comprise, or how to best enact, guidelines that ideally balance LEO activities in the service of public safety with patient health, autonomy, and privacy. The purpose of this study was to explore how a national sample of emergency physicians (EP) perceives activities of LEOs during the delivery of emergency medical care. METHODS: Members of the Emergency Medicine Practice Research Network (EMPRN) were recruited via an email-delivered, anonymous survey that elicited experiences, perceptions, and knowledge of policies that guide interactions with LEOs in the ED. The survey included multiple-choice items, which we analyzed descriptively, and open-ended questions, which we analyzed using qualitative content analysis. RESULTS: Of 765 EPs in the EMPRN, 141 (18.4%) completed the survey. Respondents represented diverse locations and years in practice. A total of 113 (82%) respondents were White, and 114 (81%) were male. Over a third reported LEO presence in the ED on a daily basis. A majority (62%) perceived LEO presence as helpful for clinicians and clinical practice. When asked about the factors deemed highly important in allowing LEOs to access patients during care, 75% reported patients' potential as a threat to public safety. A small minority of respondents (12%) considered the patients' consent or preference to interact with LEOs. While 86% of EPs felt that information-gathering by LEO was appropriate in the ED setting, only 13% were aware of policy to guide these decisions. Perceived barriers to implementation of policy in this area included: issues of enforcement; leadership; education; operational challenges; and potential negative consequences. CONCLUSION: Future research is warranted to explore how policies and practices that guide intersections between emergency medical care and law enforcement impact patients, clinicians, and the communities that health systems serve.

Consensus guidelines for diagnosis and management of anemia in epidermolysis bullosa.

BACKGROUND: Anemia is a common complication of severe forms of epidermolysis bullosa (EB). To date, there are no guidelines outlining best clinical practices to manage anemia in the EB population. The objective of this manuscript is to present the first consensus guidelines for the diagnosis and management of anemia in EB. RESULTS: Due to the lack of high-quality evidence, a consensus methodology was followed. An initial survey exploring patient preferences, concerns and symptoms related to anemia was sent to EB patients and their family members. A second survey was distributed to EB experts and focused on screening, diagnosis, monitoring and management of anemia in the different types of EB. Information from these surveys was collated and used by the panel to generate 26 consensus statements. Consensus statements were sent to healthcare providers that care for EB patients through EB-Clinet. Statements that received more than 70% approval (completely agree/agree) were adopted. CONCLUSIONS: The end result was a series of 6 recommendations which include 20 statements that will help guide management of anemia in EB patients. In patients with moderate to severe forms of EB, the minimum desirable level of Hb is 100 g/L. Treatment should be individualized. Dietary measures should be offered as part of management of anemia in all EB patients, oral iron supplementation should be used for mild anemia; while iron infusion is reserved for moderate to severe anemia, if Hb levels of > 80-100 g/L (8-10 g/dL) and symptomatic; and transfusion should be administered if Hb is < 80 g/L (8 g/dL) in adults and < 60 g/L (6 g/dL) in children.

Features of tumor-microenvironment images predict targeted therapy survival benefit in patients with EGFR-mutant lung cancer.

Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) are effective for many patients with lung cancer with EGFR mutations. However, not all patients are responsive to EGFR TKIs, including even those harboring EGFR-sensitizing mutations. In this study, we quantified the cells and cellular interaction features of the tumor microenvironment (TME) using routine H&E-stained biopsy sections. These TME features were used to develop a prediction model for survival benefit from EGFR TKI therapy in patients with lung adenocarcinoma and EGFR-sensitizing mutations in the Lung Cancer Mutation Consortium 1 (LCMC1) and validated in an independent LCMC2 cohort. In the validation data set, EGFR TKI treatment prolonged survival in the predicted-to-benefit group but not in the predicted-not-to-benefit group. Among patients treated with EGFR TKIs, the predicted-to-benefit group had prolonged survival outcomes compared with the predicted not-to-benefit group. The EGFR TKI survival benefit positively correlated with tumor-tumor interaction image features and negatively correlated with tumor-stroma interaction. Moreover, the tumor-stroma interaction was associated with higher activation of the hepatocyte growth factor/MET-mediated PI3K/AKT signaling pathway and epithelial-mesenchymal transition process, supporting the hypothesis of fibroblast-involved resistance to EGFR TKI treatment.

Cocaethylene cardiotoxicity in emergency department patients with acute drug overdose.

OBJECTIVES: Cocaine use results in over 500,000 emergency department (ED) visits annually across the United States and ethanol co-ingestion is reported in 34% of these. Commingling cocaine with ethanol results in the metabolite cocaethylene (CE), which is metabolically active for longer than cocaine alone. Current literature on the cardiotoxicity of CE compared to cocaine alone is limited and lacks consensus. This study aims to fill this gap in the literature and examine cardiovascular events in cocaine use as confirmed by urine toxicology versus CE exposure. METHODS: This was a secondary data analysis of a prospective cohort study of adult patients with acute drug overdose at two urban tertiary care hospital EDs over 4 years. Patients with positive urinary cocaine metabolites were analyzed, and outcomes were compared between patients with overdose and confirmed presence of cocaine on urine toxicology (cocaine group) and patients with cocaine and ethanol use (CE group). The primary outcome was cardiac arrest. Secondary outcomes included myocardial injury and hyperlactatemia. Data were analyzed using multivariable regression models. RESULTS: We enrolled a total of 199 patients (150 cocaine, 49 CE). Rates of cardiac arrest were significantly higher in the CE group compared to cocaine (6.1% vs. 0.67%, p = 0.048). Cocaine was significantly associated with myocardial injury compared to CE exposure (mean initial troponin 0.01 ng/ml vs. 0.16 ng/ml, p = 0.021), while hyperlactatemia was associated with CE exposure (mean initial lactate 4.1 mmol/L vs. 2.9 mmol/L, p = 0.038). CONCLUSIONS: When compared to cocaine exposure alone, CE exposure in ED patients with acute drug overdose was significantly associated with higher occurrence of cardiac arrest, higher mean lactate concentrations, and lower occurrence of myocardial injury.

A Quality Framework to Address Racial and Ethnic Disparities in Emergency Department Care.

The emergency department serves as a vital source of health care for residents in the United States, including as a safety net. However, patients from minoritized racial and ethnic groups have historically experienced disproportionate barriers to accessing health care services and lower quality of services than White patients. Quality measures and their application to quality improvement initiatives represent a critical opportunity to incentivize health care systems to advance health equity and reduce health disparities. Currently, there are no nationally recognized quality measures that track the quality of emergency care delivery by race and ethnicity and no published frameworks to guide the development and prioritization of quality measures to reduce health disparities in emergency care. To address these gaps, the American College of Emergency Physicians (ACEP) convened a working group of experts in quality measurement, health disparities, and health equity to develop guidance on establishing quality measures to address racial and ethnic disparities in the provision of emergency care. Based on iterative discussion over 3 working group meetings, we present a summary of existing emergency medicine quality measures that should be adapted to track racial and ethnic disparities, as well as a framework for developing new measures that focus on disparities in access to emergency care, care delivery, and transitions of care.

Missed Opportunities for HIV and Hepatitis C Screening Among Emergency Department Patients With Untreated Opioid Use Disorder.

OBJECTIVE: We assessed the frequency of emergency department (ED) HIV and hepatitis C (HCV) screening in a high-risk cohort of ED patients with untreated opioid use disorder (OUD). METHODS: This analysis used data from a prospective, observational study of English-speaking adults with untreated OUD enrolled from April 2017 to December 2018 in 4 urban, academic EDs. Two cohorts were defined for this analysis by self-reported negative/unknown status for HIV (cohort 1) and HCV (cohort 2). Sites featured structured screening programs throughout the entire enrollment period for HIV and during at least part of the enrollment period for HCV. We calculated the proportion tested for HIV and HCV during the study enrollment ED visit. RESULTS: Among 394 evaluated ED patients, 328 of 394 (83.2%) were not tested for HIV or HCV and 244 of 393 (62.1%) lacked a usual medical care provider. In cohort 1, 375 reported negative or unknown HIV status; 59/375 (15.7%) overall and 33/218 (15.1%) of those reporting recent injection drug use were tested for HIV. In cohort 2, 231 reported negative of unknown HCV status; 22/231 (9.5%) overall and 9/98 (9.2%) of those reporting recent injection drug use were tested for HCV. The proportion tested by the ED ranged from 3% to 25% for HIV and 4% to 32% for HCV across study sites. CONCLUSIONS: Emergency department HIV and HCV screening remains infrequent among patients with untreated OUD, including those who inject drugs, even in EDs committed to screening. Targeted HIV/HCV screening should be considered as an adjunct strategy until the ideal of universal screening is more fully achieved.

The Deep Ocean's Carbon Exhaust.

The deep ocean releases large amounts of old, pre-industrial carbon dioxide (CO2) to the atmosphere through upwelling in the Southern Ocean, which counters the marine carbon uptake occurring elsewhere. This Southern Ocean CO2 release is relevant to the global climate because its changes could alter atmospheric CO2 levels on long time scales, and also affects the present-day potential of the Southern Ocean to take up anthropogenic CO2. Here, year-round profiling float measurements show that this CO2 release arises from a zonal band of upwelling waters between the Subantarctic Front and wintertime sea-ice edge. This band of high CO2 subsurface water coincides with the outcropping of the 27.8 kg m-3 isoneutral density surface that characterizes Indo-Pacific Deep Water (IPDW). It has a potential partial pressure of CO2 exceeding current atmospheric CO2 levels (∆PCO2) by 175 ± 32 µatm. Ship-based measurements reveal that IPDW exhibits a distinct ∆PCO2 maximum in the ocean, which is set by remineralization of organic carbon and originates from the northern Pacific and Indian Ocean basins. Below this IPDW layer, the carbon content increases downwards, whereas ∆PCO2 decreases. Most of this vertical ∆PCO2 decline results from decreasing temperatures and increasing alkalinity due to an increased fraction of calcium carbonate dissolution. These two factors limit the CO2 outgassing from the high-carbon content deep waters on more southerly surface outcrops. Our results imply that the response of Southern Ocean CO2 fluxes to possible future changes in upwelling are sensitive to the subsurface carbon chemistry set by the vertical remineralization and dissolution profiles.

Survival After Out-of-Hospital Cardiac Arrest: The Role of Racial Residential Segregation.

Racial and racialized economic residential segregation has been empirically associated with outcomes across multiple health conditions but not yet explored in relation to out-of-hospital cardiac arrest (OHCA). We sought to examine if measures of racial and economic residential segregation are associated with differences in survival to discharge after OHCA for Black and White Medicare beneficiaries. Utilizing age-eligible Medicare fee-for-service claims data from 2013 to 2015, we identified OHCA claims and determined survival to discharge. The primary predictor, residential segregation, was calculated using the index of concentration at the extremes (ICE) for the beneficiary residential ZIP code. Multilevel modified Poisson regression models were used to determine the association of OHCA outcomes and ZIP code level ICE measures. In total, 194,263 OHCA cases were identified among beneficiaries residing in 75% of US ZIP codes. Black beneficiaries exhibited 12.1% survival to discharge, compared with 12.5% of White beneficiaries. In fully adjusted models of the three ICE measures accounting for differences in treating hospital characteristics, there was as high as a 28% (RR 1.28, CI 1.23-1.26) higher relative likelihood of survival to discharge in the most segregated White ZIP codes (Q5) as compared to the most segregated Black ZIP codes (Q1). Racial residential segregation is independently associated with disparities in OHCA outcomes; among Medicare beneficiaries who generated a claim after suffering an OHCA, ICE measures of racial segregation are associated with a lower likelihood of survival to discharge for those living in the most segregated Black and lower income quintiles compared to higher quintiles.