Determining mass accretion and jet mass-loss rates in post-asymptotic giant branch binary systems

Aims. In this study, we determine the morphology and mass-loss rate of jets emanating from the companion in post-asymptotic giant branch (post-AGB) binary stars with a circumbinary disk. In doing so, we also determine the mass accretion rates on to the companion and investigate the source feeding the circum-companion accretion disk. Methods. We perform a spatio-kinematic modelling of the jet of two well-sampled post-AGB binaries, BD+46442 and IRAS19135+3937, by fitting the orbital phased time series of H-alpha spectra. Once the jet geometry, velocity and scaled density structure are computed, we carry out radiative transfer modelling of the jet for the first four Balmer lines to determine the jet densities, thus allowing us to compute the jet mass-loss rates and mass accretion rates. Results. The spatio-kinematic model of the jet reproduces the observed absorption feature in the H-alpha lines. In both objects, the jets have an inner region with extremely low density. Using our radiative transfer model, we find the full three-dimensional density structure of both jets. From these results, we can compute mass-loss rates of the jets, which are of the order of 10^-7 - 10^-5 M_sol/yr. We estimate mass accretion rates onto the companion of 10^-6 - 10^-4 M_sol/yr. Conclusions. Based on the mass accretion rates found for these two objects, we conclude that the circumbinary disk is most likely the source feeding the circum-companion accretion disk. This is in agreement with the observed depletion patterns in post-AGB binaries. The high accretion rates from the circumbinary disk imply that the lifetime of the disk will be short. Mass-transfer from the post-AGB star cannot be excluded in these systems, but it is unlikely to provide a sufficient mass-transfer rate to sustain the observed jet mass-loss rates.Comment: 16 pages, 13 figures, accepted for publication in A&

The structure of jets launched from post-AGB binary systems

We focus on post-asymptotic giant branch (post-AGB) binaries and study the interaction between the different components of these complex systems. These components comprise the post-AGB primary, a main sequence secondary, a circumbinary disk, as well as a fast bipolar outflow (jet) launched by the companion. We obtained well-sampled time series of high resolution optical spectra over the last decade and these spectra provide the basis of our study. The jet is detected in absorption, at superior conjunction, when the line of sight towards the primary goes through the bipolar cone. Our spectral time series scan the jets during orbital motion. Our spatio-kinematic model is constrained by these dynamical spectra. We complement this with a radiative-transfer model in which the Balmer series are used to derive total mass-loss rates in the jets. The jets are found to be wide and display an angle-dependent density structure with a dense and slower outer region near the jet cone and a fast inner part along the jet symmetry axes. The deprojected outflow velocities confirm that the companions are main sequence companions. The total mass-loss rates are large (10^{-8} and 10^{-5}\,solar mass per year), from which we can infer that the mass-accretion rates onto the companion star must be high as well. The circumbinary disk is likely the main source for the accretion disk around the companion. All systems with full disks that start near the sublimation radius show jets, whereas for systems with evolved transition disks, this lowers to a detection rate of 50%. Objects without an infrared excess do not show jets. We conclude that jet creation in post-AGB binaries is a mainstream process. The interaction between the circumbinary disks and the central binary provide the needed accretion flow, but the presence of a circumbinary disk does not seem to be the only prerequisite to launch a jet.Comment: 17 pages, 12 figures, accepted by Astronomy and Astrophysic

Variations in end-of-life care practices in older critically ill patients with COVID-19 in Europe

BACKGROUND: Previous studies reported regional differences in end-of-life care (EoLC) for critically ill patients in Europe. OBJECTIVES: The purpose of this post-hoc analysis of the prospective multi-centre COVIP study was to investigate variations in EoLC practices among older patients in intensive care units during the coronavirus disease 2019 pandemic. METHODS: A total of 3105 critically ill patients aged 70 years and older were enrolled in this study (Central Europe: n = 1573; Northern Europe: n = 821; Southern Europe: n = 711). Generalised estimation equations were used to calculate adjusted odds ratios (aOR) to population averages. Data were adjusted for patient-specific variables (demographic, disease-specific) and health economic data (GDP, health expenditure per capita). The primary outcome was any treatment limitation, and 90-day-mortality was a secondary outcome. RESULTS: The frequency of the primary endpoint (treatment limitation) was highest in Northern Europe (48%), intermediate in Central Europe (39%), and lowest in Southern Europe (24%). The likelihood for treatment limitations was lower in Southern than in Central Europe (aOR 0.39; 95%CI 0.21-0.73; p = 0.004), even after multivariable adjustment, whereas no statistically significant differences were observed between Northern and Central Europe (aOR 0.57; 95%CI 0.27-1.22; p = 0.15). After multivariable adjustment, no statistically relevant mortality differences were found between Northern and Central Europe (aOR 1.29; 95%CI 0.80-2.09; p = 0.30) or between Southern and Central Europe (aOR 1.07; 95%CI 0.66-1.73; p = 0.78). CONCLUSION: This study shows a north-to-south gradient in rates of treatment limitation in Europe, highlighting the heterogeneity of EoLC practices across countries. However, mortality rates were not affected by these results. This article is protected by copyright. All rights reserved.publishersversionepub_ahead_of_prin

The association of the Activities of Daily Living and the outcome of old intensive care patients suffering from COVID-19

Open Access funding enabled and organized by Projekt DEAL. This study was endorsed by the ESICM. Free support for running the electronic database and was granted from the dep. of Epidemiology, University of Aarhus, Denmark. Bruno et al. Annals of Intensive Care (2022) 12:26 Page 10 of 11 The support of the study in France by a grant from Fondation Assistance Publique-Hôpitaux de Paris pour la recherche is greatly appreciated. In Norway, the study was supported by a grant from the Health Region West. In addition, the study was supported by a grant from the European Open Science Cloud (EOSC). EOSCsecretariat.eu has received funding from the European Union’s Horizon Programme call H2020-INFRAEOSC-05-2018-2019, grant agreement number 831644. This work was supported by the Collaborative Research Center SFB 1116 (German Research Foundation, DFG) and by the Forschungskommission of the Medical Faculty of the Heinrich-Heine-University Düsseldorf and No. 2020–21 to RRB for a Clinician Scientist Track. No (industry) sponsorship has been received for this investigator-initiated study.PURPOSE: Critically ill old intensive care unit (ICU) patients suffering from Sars-CoV-2 disease (COVID-19) are at increased risk for adverse outcomes. This post hoc analysis investigates the association of the Activities of Daily Living (ADL) with the outcome in this vulnerable patient group. METHODS: The COVIP study is a prospective international observational study that recruited ICU patients ≥ 70 years admitted with COVID-19 (NCT04321265). Several parameters including ADL (ADL; 0 = disability, 6 = no disability), Clinical Frailty Scale (CFS), SOFA score, intensive care treatment, ICU- and 3-month survival were recorded. A mixed-effects Weibull proportional hazard regression analyses for 3-month mortality adjusted for multiple confounders. RESULTS: This pre-specified analysis included 2359 patients with a documented ADL and CFS. Most patients evidenced independence in their daily living before hospital admission (80% with ADL = 6). Patients with no frailty and no disability showed the lowest, patients with frailty (CFS ≥ 5) and disability (ADL < 6) the highest 3-month mortality (52 vs. 78%, p < 0.001). ADL was independently associated with 3-month mortality (ADL as a continuous variable: aHR 0.88 (95% CI 0.82-0.94, p < 0.001). Being "disable" resulted in a significant increased risk for 3-month mortality (aHR 1.53 (95% CI 1.19-1.97, p 0.001) even after adjustment for multiple confounders. CONCLUSION: Baseline Activities of Daily Living (ADL) on admission provides additional information for outcome prediction, although most critically ill old intensive care patients suffering from COVID-19 had no restriction in their ADL prior to ICU admission. Combining frailty and disability identifies a subgroup with particularly high mortality. TRIAL REGISTRATION NUMBER: NCT04321265.publishersversionpublishe

A retrospective cohort study comparing differences in 30-day mortality among critically ill patients aged ≥ 70 years treated in European tax-based healthcare systems (THS) versus social health insurance systems.

In Europe, tax-based healthcare systems (THS) and social health insurance systems (SHI) coexist. We examined differences in 30-day mortality among critically ill patients aged ≥ 70 years treated in intensive care units in a THS or SHI. Retrospective cohort study. 2406 (THS n = 886; SHI n = 1520) critically ill ≥ 70 years patients in 129 ICUs. Generalized estimation equations with robust standard errors were chosen to create population average adjusted odds ratios (aOR). Data were adjusted for patient-specific variables, organ support and health economic data. The primary outcome was 30-day-mortality. Numerical differences between SHI and THS in SOFA scores (6 ± 3 vs. 5 ± 3; p = 0.002) were observed, but clinical frailty scores were similar (> 4; 17% vs. 14%; p = 0.09). Higher rates of renal replacement therapy (18% vs. 11%; p < 0.001) were found in SHI (aOR 0.61 95%CI 0.40-0.92; p = 0.02). No differences regarding intubation rates (68% vs. 70%; p = 0.33), vasopressor use (67% vs. 67%; p = 0.90) and 30-day-mortality rates (47% vs. 50%; p = 0.16) were found. Mortality remained similar between both systems after multivariable adjustment and sensitivity analyses. The retrospective character of this study. Baseline risk and mortality rates were similar between SHI and THS. The type of health care system does not appear to have played a role in the intensive care treatment of critically ill patients ≥ 70 years with COVID-19 in Europe

Lactate is associated with mortality in very old intensive care patients suffering from COVID-19: results from an international observational study of 2860 patients.

PURPOSE Lactate is an established prognosticator in critical care. However, there still is insufficient evidence about its role in predicting outcome in COVID-19. This is of particular concern in older patients who have been mostly affected during the initial surge in 2020. METHODS This prospective international observation study (The COVIP study) recruited patients aged 70 years or older (ClinicalTrials.gov ID: NCT04321265) admitted to an intensive care unit (ICU) with COVID-19 disease from March 2020 to February 2021. In addition to serial lactate values (arterial blood gas analysis), we recorded several parameters, including SOFA score, ICU procedures, limitation of care, ICU- and 3-month mortality. A lactate concentration ≥ 2.0 mmol/L on the day of ICU admission (baseline) was defined as abnormal. The primary outcome was ICU-mortality. The secondary outcomes 30-day and 3-month mortality. RESULTS In total, data from 2860 patients were analyzed. In most patients (68%), serum lactate was lower than 2 mmol/L. Elevated baseline serum lactate was associated with significantly higher ICU- and 3-month mortality (53% vs. 43%, and 71% vs. 57%, respectively, p < 0.001). In the multivariable analysis, the maximum lactate concentration on day 1 was independently associated with ICU mortality (aOR 1.06 95% CI 1.02-1.11; p = 0.007), 30-day mortality (aOR 1.07 95% CI 1.02-1.13; p = 0.005) and 3-month mortality (aOR 1.15 95% CI 1.08-1.24; p < 0.001) after adjustment for age, gender, SOFA score, and frailty. In 826 patients with baseline lactate ≥ 2 mmol/L sufficient data to calculate the difference between maximal levels on days 1 and 2 (∆ serum lactate) were available. A decreasing lactate concentration over time was inversely associated with ICU mortality after multivariate adjustment for SOFA score, age, Clinical Frailty Scale, and gender (aOR 0.60 95% CI 0.42-0.85; p = 0.004). CONCLUSION In critically ill old intensive care patients suffering from COVID-19, lactate and its kinetics are valuable tools for outcome prediction. TRIAL REGISTRATION NUMBER NCT04321265

Association of chronic heart failure with mortality in old intensive care patients suffering from Covid-19

Funding: This study was endorsed by the ESICM. Free support for running the electronic database was granted from the Department of Epidemiology, Aarhus University, Denmark. The support of the study in France by a grant from ‘Fondation Assistance Publique-Hôpitaux de Paris pour la recherche’ is greatly appreciated. In Norway, the study was supported by a grant from the Health Region West. In addition, the study was supported by a grant from the European Open Science Cloud (EOSC). EOSCsecretariat.eu has received funding from the European Union’s Horizon 2020 Framework Programme called H2020-INFRAEOSC-05-2018-2019, Grant Agreement Number 831644. This work was supported by the Forschungskommission of the Medical Faculty of the Heinrich Heine University Düsseldorf, No. 2018-32 to G.W. and No. 2020-21 to R.R.B. for a Clinician Scientist Track. Open access funding was enabled and organized by Projekt DEAL. No (industry) sponsorship has been received for this investigator-initiated study.AIMS: Chronic heart failure (CHF) is a major risk factor for mortality in coronavirus disease 2019 (COVID-19). This prospective international multicentre study investigates the role of pre-existing CHF on clinical outcomes of critically ill old (≥70 years) intensive care patients with COVID-19. METHODS AND RESULTS: Patients with pre-existing CHF were subclassified as having ischaemic or non-ischaemic cardiac disease; patients with a documented ejection fraction (EF) were subclassified according to heart failure EF: reduced (HFrEF, n = 132), mild (HFmrEF, n = 91), or preserved (HFpEF, n = 103). Associations of heart failure characteristics with the 30 day mortality were analysed in univariate and multivariate logistic regression analyses. Pre-existing CHF was reported in 566 of 3917 patients (14%). Patients with CHF were older, frailer, and had significantly higher SOFA scores on admission. CHF patients showed significantly higher crude 30 day mortality [60% vs. 48%, P < 0.001; odds ratio 1.87, 95% confidence interval (CI) 1.5-2.3] and 3 month mortality (69% vs. 56%, P < 0.001). After multivariate adjustment for confounders (SOFA, age, sex, and frailty), no independent association of CHF with mortality remained [adjusted odds ratio (aOR) 1.2, 95% CI 0.5-1.5; P = 0.137]. More patients suffered from pre-existing ischaemic than from non-ischaemic disease [233 vs. 328 patients (n = 5 unknown aetiology)]. There were no differences in baseline characteristics between ischaemic and non-ischaemic disease or between HFrEF, HFmrEF, and HFpEF. Crude 30 day mortality was significantly higher in HFrEF compared with HFpEF (64% vs. 48%, P = 0.042). EF as a continuous variable was not independently associated with 30 day mortality (aOR 0.98, 95% CI 0.9-1.0; P = 0.128). CONCLUSIONS: In critically ill older COVID-19 patients, pre-existing CHF was not independently associated with 30 day mortality. TRIAL REGISTRATION NUMBER: NCT04321265.publishersversionepub_ahead_of_prin

Sex-specific treatment characteristics and 30-day mortality outcomes of critically ill COVID-19 patients over 70 years of age-results from the prospective COVIP study.

PURPOSE Older critically ill patients with COVID-19 have been the most vulnerable during the ongoing pandemic, with men being more prone to hospitalization and severe disease than women. We aimed to explore sex-specific differences in treatment and outcome after intensive care unit (ICU) admission in this cohort. METHODS We performed a sex-specific analysis in critically ill patients ≥ 70 yr of age with COVID-19 who were included in the international prospective multicenter COVIP study. All patients were analyzed for ICU admission and treatment characteristics. We performed a multilevel adjusted regression analysis to elucidate associations of sex with 30-day mortality. RESULTS A total of 3,159 patients (69.8% male, 30.2% female; median age, 75 yr) were included. Male patients were significantly fitter than female patients as determined by the Clinical Frailty Scale (fit, 67% vs 54%; vulnerable, 14% vs 19%; frail, 19% vs 27%; P < 0.001). Male patients more often underwent tracheostomy (20% vs 14%; odds ratio [OR], 1.57; P < 0.001), vasopressor therapy (69% vs 62%; OR, 1.25; P = 0.02), and renal replacement therapy (17% vs 11%; OR, 1.96; P < 0.001). There was no difference in mechanical ventilation, life-sustaining treatment limitations, and crude 30-day mortality (50% male vs 49% female; OR, 1.11; P = 0.19), which remained true after adjustment for disease severity, frailty, age and treatment limitations (OR, 1.17; 95% confidence interval, 0.94 to 1.45; P = 0.16). CONCLUSION In this analysis of sex-specific treatment characteristics and 30-day mortality outcomes of critically ill patients with COVID-19 ≥ 70 yr of age, we found more tracheostomy and renal replacement therapy in male vs female patients, but no significant association of patient sex with 30-day mortality. STUDY REGISTRATION www. CLINICALTRIALS gov (NCT04321265); registered 25 March 2020)