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Background: Gastrointestinal dysfunction is a common complication of medical nutrition therapy in critically ill patients. Whether prone positioning leads to a deterioration in gastrointestinal function has not been fully clarified. Thus, we aimed to analyze the influence of prone positioning on the tolerance of medical nutrition therapy. Methods: We conducted a retrospective analysis of 102 SARS-CoV-2 infected patients with venovenous extracorporeal membrane oxygenation support (VV ECMO). Gastric residual volume (GRV) was used to assess the tolerance of enteral nutrition. Results: Nutritional data were collected for 2344 days. Undernutrition was observed in 40.8%, with a significantly higher incidence on days in prone position (48.4% versus 38.6%, p < 0.001). On days in supine position, significantly more calories were administered enterally than on days in prone position (p < 0.001). The mean GRV/24 h was 111.1 mL on days in supine position and 187.3 mL on days in prone position (p < 0.001). Prone positioning was associated with higher rates of GRV of ≥500 mL/24 h independent of age, disease severity at ECMO start, ECMO runtime and ICU length of stay (adjusted hazard ratio: 4.06; 95%CI: 3.0–5.5; p < 0.001). Conclusions: Prone position was associated with lower tolerance of enteral nutrition, as indicated by an increased GRV. As a result, reduced enteral nutritional support was administered. [ABSTRACT FROM AUTHOR]

Although extracorporeal membrane ventilation offers the possibility for low-frequency ventilation, protocols commonly used in patients with acute respiratory distress syndrome (ARDS) and treated with extracorporeal membrane oxygenation (ECMO) vary largely. Whether strict adherence to low-frequency ventilation offers benefit on important outcome measures is poorly understood. Background/Objectives: This pilot clinical study investigated the efficacy of low-frequency ventilation on ventilator-free days (VFDs) in patients suffering from ARDS who were treated with ECMO therapy. Methods: In this single-center randomized controlled trial, 44 (70% male) successive ARDS patients treated with ECMO (aged 56 ± 12 years, SAPS III 64 (SD ± 14)) were randomly assigned 1:1 to the control group (conventional ventilation) or the treatment group (low-frequency ventilation during first 72 h on ECMO: respiratory rate 4–5/min; PEEP 14–16 cm H2O; plateau pressure 23–25 cm H2O, tidal volume: <4 mL/kg). The primary endpoint was VFDs at day 28 after starting ECMO treatment. The major secondary endpoint was ICU mortality, 28-day mortality and 90-day mortality. Results: Twenty-three (52%) patients were successfully weaned from ECMO and were discharged from the intensive care unit (ICU). Twelve patients in the treatment group and five patients in the control group showed more than one VFD at day 28 of ECMO treatment. VFDs were 3.0 (SD ± 5.5) days in the control group and 5.4 (SD ± 6) days in the treatment group (p = 0.117). Until day 28 of ECMO initiation, patients in the treatment group could be successfully weaned off of the ventilator more often (OR of 0.164 of 0 VFDs at day 28 after ECMO start; 95% CI 0.036–0.758; p = 0.021). ICU mortality did not differ significantly (36% in treatment group and 59% in control group; p = 0.227). Conclusions: Low-frequency ventilation is comparable to conventional protective ventilation in patients with ARDS who have been treated with ECMO. However, low-frequency ventilation may support weaning from invasive mechanical ventilation in patients suffering from ARDS and treated with ECMO therapy. [ABSTRACT FROM AUTHOR]

Background/Objectives: Septic shock is a severe condition with high mortality necessitating precise prognostic tools for improved patient outcomes. This study aimed to evaluate the collective predictive value of the Simplified Acute Physiology Score 3 (SAPS-3) and lactate measurements (initial, peak, last, and clearance rates within the first 24 h) in patients with septic shock. Specifically, it sought to determine how these markers enhance predictive accuracy for 28-day mortality beyond SAPS-3 alone. Methods: This retrospective cohort study analyzed data from 66 septic shock patients at two ICUs of Vienna General Hospital (2017–2019). SAPS-3 and lactate levels (initial, peak, last measurement within 24 h, and 24 h clearance) were obtained from electronic health records. Logistic regression models were constructed to identify predictors of 28-day mortality, and receiver operating characteristic (ROC) curves assessed predictive accuracy. Results: Among 66 patients, 36 (55%) died within 28 days. SAPS-3 scores significantly differed between survivors and non-survivors (76 vs. 85 points; p = 0.016). First, last, and peak lactate were significantly higher in non-survivors compared to survivors (all p < 0.001). The combination of SAPS-3 and first lactate produced the highest predictive accuracy (AUC = 80.6%). However, 24 h lactate clearance was not predictive of mortality. Conclusions: Integrating SAPS-3 with lactate measurements, particularly first lactate, improves predictive accuracy for 28-day mortality in septic shock patients. First lactate serves as an early, robust prognostic marker, providing crucial information for clinical decision-making and care prioritization. Further large-scale studies are needed to refine these predictive tools and validate their efficacy in guiding treatment strategies. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study sought to evaluate the efficacy of various lactate measurements within the first 24 h post-intensive care unit (ICU) admission for predicting 30-day mortality in cardiogenic shock patients. It compared initial lactate levels, 24 h levels, peak levels, and 24 h clearance, alongside the Simplified Acute Physiology Score 3 (SAPS3) score, to enhance early treatment decision-making. Methods: A retrospective analysis of 64 patients assessed the prognostic performance of lactate levels and SAPS3 scores using logistic regression and AUROC calculations. Results: Of the baseline parameters, only the SAPS3 score predicted survival independently. The lactate level after 24 h (LL) was the most accurate predictor of mortality, outperforming initial levels, peak levels, and 24 h-clearance, and showing a significant AUROC. LL greater than 3.1 mmol/L accurately predicted mortality with high specificity and moderate sensitivity. Conclusions: Among lactate measurements for predicting 30-day mortality in cardiogenic shock, the 24 h lactate level was the most effective one, suggesting its superiority for early prognostication over initial or peak levels and lactate clearance. [ABSTRACT FROM AUTHOR]

Background: Prolonged critical illness is often accompanied by an impairment of adrenal function, which has been frequently related to conditions complicating patient management. The presumed connection between hypoxia and the pathogenesis of this critical-illness-related corticosteroid insufficiency (CIRCI) might play an important role in patients with severe acute respiratory distress syndrome (ARDS). Since extracorporeal membrane oxygenation (ECMO) is frequently used in ARDS, but data on CIRCI during this condition are scarce, this study reports the behaviour of adrenal function parameters during oxygenation support with veno-venous (vv)ECMO in coronavirus disease 2019 (COVID-19) ARDS. Methods: A total of 11 patients undergoing vvECMO due to COVID-19 ARDS at the Medical University of Vienna, who received no concurrent corticosteroid therapy, were retrospectively included in this study. We analysed the concentrations of cortisol, aldosterone, and angiotensin (Ang) metabolites (Ang I-IV, Ang 1-7, and Ang 1-5) in serum via liquid chromatography/tandem mass spectrometry before, after 1 day, 1 week, and 2 weeks during vvECMO support and conducted correlation analyses between cortisol and parameters of disease severity. Results: Cortisol concentrations appeared to be lowest after initiation of ECMO and progressively increased throughout the study period. Higher concentrations were related to disease severity and correlated markedly with interleukin-6, procalcitonin, pH, base excess, and albumin during the first day of ECMO. Fair correlations during the first day could be observed with calcium, duration of critical illness, and ECMO gas flow. Angiotensin metabolite concentrations were available in a subset of patients and indicated a more homogenous aldosterone response to plasma renin activity after 1 week of ECMO support. Conclusion: Oxygenation support through vvECMO may lead to a partial recovery of adrenal function over time. In homogenous patient collectives, this novel approach might help to further determine the importance of adrenal stress response in ECMO and the influence of oxygenation support on CIRCI. [ABSTRACT FROM AUTHOR]

The United States is in a housing affordability crisis, with nearly half of all renter households spending more than 30% of their incomes on rent and utilities each month. This traditional measure of housing affordability may understate the hardships renter households face because it does not consider the array of expenses households have. Whereas housing policy has relied on percentage-of-income measures to indicate whether housing is affordable, researchers over the last three decades have called for a residual income approach that uses spending estimates to calculate what a household can actually afford. This article examines the extent of the affordability crisis by comparing standard cost burden rates for working-age renter households with residual-income cost burdens. Using the Economic Policy Institute's Family Budget Calculator and the 2018 American Community Survey, we estimate the number of renter households that do not have enough income to afford a comfortable standard of living after paying rent and utilities. We investigate several policy levers, finding that a combined policy that addresses both housing and transportation affordability would have the largest impact on reducing residual-income cost burdens. [ABSTRACT FROM AUTHOR]

Construction of absorbing boundary conditions (ABCs) for nonlocal models is generally challenging, primarily due to the fact that nonlocal operators are commonly associated with volume constrained boundary conditions. Moreover, application of Fourier and Laplace transforms, which are essential for the majority of available methods for ABCs, to nonlocal models is complicated. In this paper, we propose a simple method to construct accurate ABCs for peridynamic scalar wave‐type problems in viscous media. The proposed ABCs are constructed in the time and space domains and are of Dirichlet type. Consequently, their implementation is relatively simple, since no derivatives of the wave field are required. The proposed ABCs are derived at the continuum level, from a semi‐analytical solution of the exterior domain using harmonic exponential basis functions in space and time (plane‐wave modes). The numerical implementation is done using a meshfree collocation approach employed within a boundary layer adjacent to the interior domain boundary. The modes satisfy the peridynamic numerical dispersion relation, resulting in a compatible solution of the interior region (near‐field) with that of the exterior region (far‐field). The accuracy and stability of the proposed ABCs are demonstrated with several numerical examples in two‐dimensional unbounded domains. [ABSTRACT FROM AUTHOR]

Drawing on the nationally representative Census Bureau Household Pulse Survey (N = 443,375), this study examined how pre-pandemic and pandemic-induced vulnerabilities shaped racial inequalities in housing insecurity from August to December 2020. Theorizing the pandemic as a “systemic shock,” this article helps explain how racial inequalities are reproduced both as legacies of long-standing disparities and through widespread, societal moments of disruption. Our results indicated that Black, Hispanic, and Asian households were all significantly more likely to fall behind on housing payments than white households. We found that preexisting racial inequities, including in educational attainment, household income, and homeownership rates, largely explained racial disparities in housing insecurity during COVID-19. However, the pandemic also induced new pathways to racial inequalities. Black and Hispanic households were more likely to lose income and when they lost income, they faced a greater likelihood of experiencing housing insecurity. We conclude by highlighting the importance of theorizing disruptive systemic shocks to understand racial inequalities and discuss findings of both disparities faced by Black and Hispanic households, as well as underrecognized housing insecurity among Asian Americans. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) and its alloys are promising materials for temporary bone implants due to their mechanical properties and biocompatibility. The most challenging aspect of Mg-based implants involves adapting the degradation rate to the human body, which requires extensive in vitro and in vivo testing. Given that in vivo tests are significantly more labour-intensive than in vitro and ethics prohibit direct experiments on animals or humans, attempts are commonly undertaken to infer conclusions on in vivo degradation behavior from in vitro experiments. However, there is a wide gap between these tests, and in vitro testing is often a poor predictor of in vivo outcomes. In the development of biodegradable Mg-based implants, considerable efforts are being made to reduce the overall time and cost of in vitro and in vivo testing. Finding a suitable alternative to predict the degradation of Mg alloys, however, remains challenging. We present computational modelling as a possible alternative to bridge the gap between in vitro and in vivo testing, thus reducing overall cost, duration and number of experiments. However, traditional modelling approaches for complex biodegradable systems are still rather time-consuming and require a clear definition of the relations between input parameters and the model result. In this study, Kriging surrogate models based on the peridynamic in vitro degradation model were developed to simulate the degradation behavior for two main alloys, Mg-5Gd and Mg-10Gd, for both in vitro and in vivo cases. Using Kriging surrogate models, the simulation parameters were calibrated to the volume loss data from in vitro and in vivo experiments. In vivo degradation of magnesium has one order of magnitude higher apparent diffusion coefficients than in vitro degradation, thus yielding the higher volume loss observed in vivo than in vitro. On the basis of the diffusivity of the Mg 2 +  ions modeled under in vitro degradation, Kriging surrogate models were able to simulate the in vivo degradation behavior of Mg-xGd with a ratio between 0.46 and 0.5, indicating that the surrogate-modelling approach is able to bridge the gap between in vitro and in vivo degradation rates for Mg-xGd implants. [ABSTRACT FROM AUTHOR]

Purpose Pump-driven veno-venous extracorporeal CO.sub.2-removal (ECCO.sub.2-R) increasingly takes root in hypercapnic lung failure to minimize ventilation invasiveness or to avoid intubation. A recently developed device (iLA activve.sup.®, Novalung, Germany) allows effective decarboxylation via a 22 French double lumen cannula. To assess determinants of gas exchange, we prospectively evaluated the performance of ECCO.sub.2-R in ten patients receiving iLA activve.sup.® due to hypercapnic respiratory failure. Methods Sweep gas flow was increased in steps from 1 to 14 L/min at constant blood flow (phase 1). Similarly, blood flow was gradually increased at constant sweep gas flow (phase 2). At each step gas transfer via the membrane as well as arterial blood gas samples were analyzed. Results During phase 1, we observed a significant increase in CO.sub.2 transfer together with a decrease in PaCO.sub.2 levels from a median of 66 mmHg (range 46-85) to 49 (31-65) mmHg from 1 to 14 L/min sweep gas flow (p < 0.0001), while arterial oxygenation deteriorated with high sweep gas flow rates. During phase 2, oxygen transfer significantly increased leading to an increase in PaO.sub.2 from 67 (49-87) at 0.5 L/min to 117 (66-305) mmHg at 2.0 L/min (p < 0.0001). Higher blood flows also significantly enhanced decarboxylation (p < 0.0001). Conclusions Increasing sweep gas flow results in effective CO.sub.2-removal, which can be further reinforced by raising blood flow. The clinically relevant oxygenation effect in this setting could broaden the range of indications of the system and help to set up an individually tailored configuration., Author(s): Alexander Hermann [sup.1], Katharina Riss [sup.1], Peter Schellongowski [sup.1], Andja Bojic [sup.1], Philipp Wohlfarth [sup.1], Oliver Robak [sup.1], Wolfgang R. Sperr [sup.1], Thomas Staudinger [sup.1] Author Affiliations: (1) grid.22937.3d, [...]

Background: Patients receiving extracorporeal membrane oxygenation (ECMO) support are at high risk for malnutrition. There are currently no general nutrition guidelines for coronavirus disease 2019 (COVID-19) patients during ECMO therapy. Methods: We conducted a retrospective analysis of COVID-19 patients requiring venovenous ECMO support at a large tertiary hospital center. Nutrition goals were calculated using 25 kcal/kg body weight (BW)/day. Associations between nutrition support and outcome were evaluated using Kaplan–Meier and multivariable Cox regression analyses. Results: Overall, 102 patients accounted for a total of 2344 nutrition support days during ECMO therapy. On 40.6% of these days, nutrition goals were met. Undernutrition was found in 40.8%. Mean daily calorie delivery was 73.7% of calculated requirements, mean daily protein delivery was 0.7 g/kg BW/d. Mean energy intake of ≥70% of calculated targets was associated with significantly lower ICU mortality independently of age, disease severity at ECMO start and body mass index (adjusted hazard ratio: 0.372, p = 0.007). Conclusions: Patients with a mean energy delivery of ≥70% of calculated targets during ECMO therapy had a better ICU survival compared to patients with unmet energy goals. These results indicate that adequate nutritional support needs to be a major priority in the treatment of COVID-19 patients requiring ECMO support. [ABSTRACT FROM AUTHOR]

Background: Monitoring of blood coagulation is essential in ECMO patients. We investigated the prevalence of lupus anticoagulant (LA) and its association with coagulation testing and hemostaseologic complications in patients treated with ECMO. Methods: This is a retrospective analysis including adult patients who received ECMO at a medical intensive care unit at the Medical University of Vienna. The primary outcome was the prevalence of LA. Secondary outcomes included conditions associated with LA positivity, rates of bleeding and thromboembolic events, as well as the proportions of aPTT and antiXa measurements within the target range. Results: Between 2013 and 2021 193 patients received ECMO, in 62 (32%) of whom LA diagnostics were performed. Twenty-two (35%) patients tested positive. LA positive patients had more frequently received VV ECMO (77.3% vs 34.3%; p = 0.002), were more frequently diagnosed with viral respiratory infections (SARS-CoV2: 45.5% vs 20%; p = 0.041, influenza virus: 22.7% vs 0%; p = 0.003), had a longer ECMO treatment duration (25 vs 10 days; p = 0.011) and a longer ICU stay (48 vs 25 days; p = 0.022), but similar rates of bleeding and thromboembolic events. [ABSTRACT FROM AUTHOR]

Rationale: Prostaglandin E1 (alprostadil; PGE1), in addition to low-dose unfractionated heparin, increases the biocompatibility of extracorporeal systems and enhances the efficacy of artificial organs without increasing bleeding risk. Objectives: We investigated the safety and efficacy of PGE1 in adults receiving venovenous extracorporeal membrane oxygenation (ECMO). Methods: This study was a randomized, double-blind, placebo-controlled phase II pilot trial at two medical intensive care units at the Medical University of Vienna, Austria. Adults with venovenous ECMO were randomly assigned to receive an intravenous infusion of 5 ng/kg/min PGE1 or placebo (0.9% saline) in addition to standard anticoagulation with unfractionated heparin. Measurements and Main Results: The primary outcome was the rate of transfused packed red blood cells per ECMO day. Secondary outcomes were the incidence of and time to clinically overt bleeding and thromboembolic events. A post hoc subgroup analysis included only patients with coronavirus disease (COVID-19). Between September 2016 and April 2021, of 133 screened patients, 50 patients were randomized, of whom 48 received the assigned study medication (24 per group). The transfusion rate was similar between groups (0.41 vs. 0.39; P = 0.733). PGE1 was associated with fewer thromboembolic events (7 vs. 16; P = 0.020) and longer thromboembolism-free time (hazard ratio [HR], 0.302; P = 0.01), fewer clinically overt bleeding events (2 vs. 11; P = 0.017), and longer bleeding-free time (HR, 0.213; P = 0.047). In patients with COVID-19 (n = 25), the HRs for clinically overt bleeding and thromboembolism were 0.276 (95% confidence interval, 0.035-2.186) and 0.521 (95% confidence interval, 0.149-1.825), respectively. Conclusions: Add-on treatment with PGE1 was safe but did not meet the primary endpoint of reducing the rate of red blood cell transfusions in patients receiving venovenous ECMO. Larger studies need to evaluate the safety and efficacy of additional PGE1 in ECMO. Clinical trial registered with EudraCT (2015-005014-30) and www.clinicaltrials.gov (NCT02895373). [ABSTRACT FROM AUTHOR]

The reactions of carbodiimides with the iron arylborylene complex [Fe=BDur(CO)3(PMe3)] (Dur=2,3,5,6‐Me4C6H) and the iron bis(borylene) complex [Fe{=BDur}{=BN(SiMe3)2}(CO)3] yield a wide variety of temperature‐dependent products, including known FeBNC and novel FeBNB metallacycles, complexes of N‐heterocyclic boracarbene and spiro‐boracarbene ligands and a unique 1,3,2,4‐diazadiborolyl pianostool complex, characterized by NMR spectroscopy and X‐ray crystallography. The product distributions can be rationalized by considering sequences of cycloaddition, metathesis, insertion, and C−H activation pathways mainly governed by sterics. [ABSTRACT FROM AUTHOR]

Acute respiratory failure (ARF) is the main reason for ICU admission following allogeneic hematopoietic stem cell transplantation (HSCT). Extracorporeal CO2 removal (ECCO2R) can be used as an adjunct to mechanical ventilation in patients with severe hypercapnia but has not been assessed in HSCT recipients. Retrospective analysis of all allogeneic HSCT recipients ≥18 years treated with ECCO2R at two HSCT centers. 11 patients (m:f = 4:7, median age: 45 [IQR: 32‐58] years) were analyzed. Acute leukemia was the underlying hematologic malignancy in all patients. The time from HSCT to ICU admission was 37 [8‐79] months, and 9/11 (82%) suffered from chronic graft‐versus‐host disease (GVHD) with lung involvement. Pneumonia was the most frequent reason for ventilatory decompensation (n = 9). ECCO2R was initiated for severe hypercapnia (PaCO2: 96 [84‐115] mm Hg; pH: 7.13 [7.09‐7.27]) despite aggressive mechanical ventilation (invasive, n = 9; non‐invasive, n = 2). ECCO2R effectively resolved blood gas disturbances in all patients, but only 2/11 (18%) could be weaned off ventilatory support, and one (9%) patient survived hospital discharge. Progressive respiratory and multiorgan dysfunction were the main reasons for treatment failure. ECCO2R was technically feasible but resulted in a low survival rate in our cohort. A better understanding of the prognosis of ARF in patients with chronic GVHD and lung involvement is necessary before its use can be reconsidered in this setting. [ABSTRACT FROM AUTHOR]

Reduction of (CAAC)BBr2(NCS) (CAAC=cyclic alkyl(amino)carbene) in the presence of a Lewis base L yields tricoordinate (CAAC)LB(NCS) borylenes which undergo reversible E/Z‐isomerization. The same reduction in the absence of L yields deep blue, bis(CAAC)‐stabilized, boron‐doped, aromatic thiazolothiazoles resulting from the dimerization of dicoordinate (CAAC)B(NCS) borylene intermediates. [ABSTRACT FROM AUTHOR]

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Whereas the reduction of N-heterocyclic carbene (NHC)-stabilised cymantrenyldibromoboranes, (NHC)BBr2Cym, in benzene results in the formation of the corresponding diborenes (NHC)2B2Cym2, a change of solvent to THF yields a borylene analogue of the form (NHC)2BCym, stabilised through a boratafulvene/borafulvenium conformation. [ABSTRACT FROM AUTHOR]

Author(s): Alexander Hermann [sup.1], Thomas Staudinger [sup.1] Author Affiliations: (1) grid.22937.3d, 0000000092598492, Department of Medicine I, Medical University of Vienna, , Vienna, Austria Dear Editor, Du et al. [1] raise [...]