ABSTRACT
Refractory hypoxemia during veno-venous (V-V) extracorporeal membrane oxygenation (ECMO) may require an additional cannula (VV-V ECMO) to improve oxygenation. This intervention includes risk of recirculation and other various adverse events (AEs) such as injury to the lung, cannula malpositioning, bleeding, circuit or cannula thrombosis requiring intervention (i.e., clot), or cerebral injury. During the study period, 23 of 142 V-V ECMO patients were converted to VV-V utilizing two separate cannulas for bi-caval drainage with an additional upper extremity cannula placed for return. Of those, 21 had COVID-19. In the first 24 h after conversion, ECMO flow rates were higher (5.96 vs 5.24 L/min, p = .002) with no significant change in pump speed (3764 vs 3630 revolutions per minute [RPMs], p = .42). Arterial oxygenation (PaO2) increased (87 vs 64 mmHg, p < .0001) with comparable pre-oxygenator venous saturation (61 vs 53.3, p = .12). By day 5, flows were similar to pre-conversion values at lower pump speed but with improved PaO2. Unadjusted survival was similar in those converted to VV-V ECMO compared to V-V ECMO alone (70% [16/23] vs 66.4% [79/119], p = .77). In a mixed effect regression model, any incidence of AEs, demonstrated a negative impact on PaO2 in the first 48 h but not at day 5. VV-V ECMO improved oxygenation with increasing flows without a significant difference in AEs or pump speed. AEs transiently impacted oxygenation. VV-V ECMO is effective and feasible strategy for refractory hypoxemia on VV-ECMO allowing for higher flow rate and unchanged pump speed.
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The co-occurrence of microplastics (MPs) with potentially toxic metals in the environment stresses the need to address their physicochemical interactions and the potential ecological and human health implications. Here, we investigated the reaction of aqueous U with agricultural soil and high-density polyethylene (HDPE) through the integration of batch experiments, microscopy, and spectroscopy. The aqueous initial concentration of U (100 µM) decreased between 98.6 and 99.2 % at pH 5 and between 86.2 and 98.9 % at pH 7.5 following the first half hour of reaction with 10 g of soil. In similar experimental conditions but with added HDPE, aqueous U decreased between 98.6 and 99.7 % at pH 5 and between 76.1 and 95.2 % at pH 7.5, suggesting that HDPE modified the accumulation of U in soil as a function of pH. Uranium-bearing precipitates on the cracked surface of HDPE were identified by SEM/EDS after two weeks of agitation in water at both pH 5 and 7.5. Accumulation of U on the near-surface region of reacted HDPE was confirmed by XPS. Our findings suggest that the precipitation of U was facilitated by the weathering of the surface of HDPE. These results provide insights about surface-mediated reactions of aqueous metals with MPs, contributing relevant information about the mobility of metals and MPs at co-contaminated agricultural sites.
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PURPOSE OF STUDY: The COVID-19 pandemic has led to a significant increase in the use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) as a bridge to transplantation versus recovery. Unlike other etiologies of acute respiratory distress syndrome (ARDS), utilization of V-V ECMO in COVID-19 has been associated with longer duration of ECMO support requirements. Our team sought to evaluate outcomes associated with prolonged duration of ECMO support in this patient population. METHODS: Single-center retrospective review of patients who were placed on ECMO due to COVID-19 associated ARDS. Specifically examining outcomes-transplant free survival, mortality and discharge rates-of patients requiring V-V ECMO support for greater than 50 days. RESULTS: The median age of the cohort was 48 years and 13 patients (72%) were males. The median duration of ECMO support was 84 days (IQR 55-106). 11 patients (61%) had right ventricular dysfunction and 13 patients (72%) had pneumothoraces. There was a 33% percent (n = 6) mortality rate within cohort. One patient continues to require ECMO support at time of abstract submission. 11 patients (61%) patients were discharged, of which 3 patients required a lung transplant. SUMMARY: Prolonged V-V ECMO can be associated with comparable outcomes to conventional V-V ECMO runs that are relatively shorter in duration. With availability of device and staffing, prolonged ECMO runs can potentially be justified in a highly selected patient population.
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OBJECTIVE: Obese patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory failure (ARDS) often require prolonged intubation. However, data are sparse regarding optimal tracheostomy timing in obese adults with COVID-19 requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). This study retrospectively describes the course of obese patients with COVID-19 who underwent tracheostomy on VV-ECMO between March 2020 and December 2022. METHODS: There were 62 participants with a median age of 43 (interquartile range [IQR] 33 to 53) years and a median body mass index of 42 (IQR 34 to 50) kg/m2 who received VV-ECMO for COVID-19-associated ARDS. Of those, 42 underwent tracheostomy on VV-ECMO, and 50% (n = 21) of the 42 patients underwent early (within 14 days of initiated ventilatory support) tracheostomy. RESULTS: Among patients who received tracheostomies, the combined respiratory tract and lung parenchymal bleeding rate was 29% (n = 12), but only 7% required surgical intervention for bleeding from the tracheostomy site (n = 3). The hospital length of stay (LOS) was 42 (IQR 36 to 57) days, and mortality rate was 38% (n = 16). Tracheostomy timing was not associated with differences in respiratory tract bleeding, mechanical ventilatory support duration, VV-ECMO support duration, intensive care unit LOS, hospital LOS, mortality, or survival probability. CONCLUSIONS: Although an individualized and holistic approach to clinical decision making continues to be necessary, the findings of this study suggest that early tracheostomy may be performed safely in obese patients with COVID-19 on VV-ECMO.
Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Adult , Humans , Middle Aged , COVID-19/complications , COVID-19/epidemiology , Tracheostomy , Retrospective Studies , Respiratory Distress Syndrome/therapyABSTRACT
Negative pressure pulmonary edema (NPPE) may result in respiratory failure refractory to conventional management strategies. Venovenous extracorporeal membrane oxygenation (VV ECMO) can serve as a rescue therapy in cases of severe respiratory failure. Rapid initiation of VV ECMO can decrease morbidity and mortality while facilitating early liberation from mechanical ventilation and promoting early rehabilitation. We describe the successful utilization of VV ECMO as rescue therapy for severe NPPE-induced hypoxic respiratory failure and peri-arrest state in the postanesthesia care unit (PACU) in a patient with postextubation airway obstruction after undergoing patellar tendon repair.
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The magnetic properties of permalloy-based trilayers of the form Py0.8Cu0.2/Py0.4Cu0.6/Py/IrMn were studied as the spacer layer undergoes a paramagnetic to ferromagnetic phase transition. We find the coupling between the free Py0.8Cu0.2 layer and the exchange bias pinned Py to be strongly temperature-dependent: there is negligible coupling above the Curie temperature of the Py0.4Cu0.6 spacer layer, strong ferromagnetic coupling below that temperature, and a tunable coupling between these extremes. Polarized neutron reflectometry was used to measure the depth profile of the magnetic order in the system, allowing us to correlate the order parameter with the coupling strength. The thickness dependence shows that these are interface effects with an inverse relationship to thickness, and that there is a magnetic proximity effect that enhances the Curie temperature of the spacer layer with characteristic length scale of about 7 nm. As a demonstration of potential functionality of such a system, the structure is shown to spontaneously flip from the antiparallel to parallel magnetic configuration once the spacer layer has developed long-range magnetic order.
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Physical therapy (PT) utilization in patients requiring mechanical circulatory support (MCS) and extracorporeal membrane oxygenation (ECMO) has been reported; however, little is known about intensive rehabilitation and associated outcomes in patients requiring extended complex MCS and/or ECMO support.Authors sought to explore safety, feasibility and outcomes associated with active rehabilitation in patients requiring prolonged advanced MCS/ECMO support.Single-center retrospective series evaluated functional, clinical, and longitudinal outcomes of sample of eight critically ill, adult (≥18 years of age) patients who underwent a intensive rehabilitation while receiving prolonged MCS/ECMO through advanced configurations including: venovenous (VV-ECMO), venoarterial (VA-ECMO), oxygenator with right ventricular assist device (Oxy-RVAD) and right ventricular assist device (RVAD).406 sessions were conducted; 246 during provision of advanced MCS/ECMO support.Incidence of major adverse events-accidental decannulation, migration of cannulas, circuit failure, hemorrhage, major flow limitations, and major hemodynamic instability-was 1.2 events per 100 sessions. None of reported major adverse events impeded longitudinal ability to participate in PT. Increased time to PT initiation was associated with a statistically significant increase in intensive care unit (ICU) length-of-stay (ß1 1.93, CI 0.55-3.30) and reduced ambulatory distance during last session on MCS/ECMO (ß1 -47.64, CI - 93.93, -1.66). All patients survived to hospital discharge and 12 months from sentinel hospitalization. Amongst those patients discharged to an inpatient rehabilitation center (n = 4), all were discharged home within 3 months.Findings support the safety and feasibility of active rehabilitational PT in patients requiring extended durations of advanced MCS/ECMO support. Moreover, it highlights potentially associated benefits of this degree of intensive rehabilitation for these unique patients. Further investigation is needed to identify associations with longitudinal clinical outcomes, as well as predictors of success in this population.
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Amidst the pandemic, geographical boundaries presented challenges to those in need of higher levels of care from referral centers. Authors sought to evaluate potential predictors of treatment success; assess our transport and remote cannulation process; and identify transport associated complications.Retrospective series of critically ill adults with COVID-19 transferred by our Extracorporeal Membrane Oxygenation (ECMO) team 24 March 2020 through 8 June 2021. Descriptive statistics and associated interquartile ranges (IQR) were used to summarize the data.Sixty-three patients with COVID associated acute respiratory distress syndrome (ARDS) requiring ECMO support were admitted to our ECMO center. Mean age was 44 years old (SD 12; IQR 36-56). 59% (n = 37) of patients were male. Average body mass index was 39.7 (SD 11.3; IQR 31-48.5). Majority of patients (77.8%; n = 35) had severe ARDS. Predictors of treatment success were not observed.Transport distances ranged from 2.2 to 236 miles (median 22.5 miles; IQR 8.3-79); round trip times from 18 to 476 min (median 83 min; IQR 44-194). No transport associated complications occurred. Median duration of ECMO support was 17 days (IQR 9.5-34.5). Length of stay in the Intensive Care Unit (median 36 days; IQR 17-49) and hospital (median 39 days; IQR 25-57) varied. Amongst those discharged, 60% survived.
Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Adult , Humans , Male , Female , COVID-19/therapy , Pandemics , Retrospective Studies , Respiratory Distress Syndrome/therapyABSTRACT
OBJECTIVE: Investigate the effects of scheduling task complexity on human performance for novice schedulers creating spaceflight timelines. BACKGROUND: Future astronauts will be expected to self-schedule, yet will not be experts in creating timelines that meet the complex constraints inherent to spaceflight operations. METHOD: Conducted a within-subjects experiment to evaluate scheduling task performance in terms of scheduling efficiency, effectiveness, workload, and situation awareness while manipulating scheduling task complexity according to the number of constraints and type of constraints. RESULTS: Each participant (n = 15) completed a set of scheduling problems. Results showed main effects of the number of constraints and type of constraint on efficiency, effectiveness, and workload. Significant interactions were observed in situation awareness and workload for certain types of constraints. Results also suggest that a lower number of constraints may be manageable by novice schedulers when compared to scheduling activities without constraints. CONCLUSION: Results suggest that novice schedulers' performance decreases with a high number of constraints, and future scheduling aids may need to target a specific type of constraint. APPLICATION: Knowledge on the effect of scheduling task complexity will help design scheduling systems that will enable self-scheduling for future astronauts. It will also inform other domains that conduct complex scheduling, such as nursing and manufacturing.
Subject(s)
Space Flight , Workload , Humans , Task Performance and AnalysisABSTRACT
Extracorporeal membrane oxygenation is emerging as a vital resource for survival of patients with acute respiratory distress syndrome related to COVID-19. Although recent research provides much insight into the advantages of extracorporeal membrane oxygenation in this patient population, little has been published on its use in pregnancy. This case study describes the use of venovenous extracorporeal membrane oxygenation in a young pregnant woman with acute respiratory distress syndrome due to COVID-19. It illustrates the benefits of a multidisciplinary approach to this treatment modality, allowing time for a fetus to become viable while preserving the life of the mother. In this case, the mother was able to return home after receiving this therapy and resume normal activities of daily living independently.
Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Activities of Daily Living , COVID-19/therapy , Female , Humans , Pregnancy , Respiratory Distress Syndrome/therapyABSTRACT
We provide statistical measures and additional analyses showing that our original analyses were sound. We use a generalized linear mixed model to account for program-to-program differences with program as a random effect without stratifying with tier and found the GRE-P (Graduate Record Examination physics test) effect is not different from our previous findings, thereby alleviating concern of collider bias. Variance inflation factors for each variable were low, showing that multicollinearity was not a concern. We show that range restriction is not an issue for GRE-P or GRE-V (GRE verbal), and only a minor issue for GRE-Q (GRE quantitative). Last, we use statistical measures of model quality to show that our published models are better than or equivalent to several alternates.
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This study aims to understand the effectiveness of typical admissions criteria in identifying students who will complete the Physics Ph.D. Multivariate statistical analysis of roughly one in eight physics Ph.D. students from 2000 to 2010 indicates that the traditional admissions metrics of undergraduate grade point average (GPA) and the Graduate Record Examination (GRE) Quantitative, Verbal, and Physics Subject Tests do not predict completion as effectively admissions committees presume. Significant associations with completion were found for undergraduate GPA in all models and for GRE Quantitative in two of four studied models; GRE Physics and GRE Verbal were not significant in any model. It is notable that completion changed by less than 10% for U.S. physics major test takers scoring in the 10th versus 90th percentile on the Quantitative test. Aside from these limitations in predicting Ph.D. completion overall, overreliance on GRE scores in admissions processes also selects against underrepresented groups.
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Pregnancy in the presence of serious illness and treatment can create a moral and ethical struggle. There is little literature to provide an ethical framework for decision making when women become pregnant while receiving aggressive care for any serious illness. The family and care team often have moral distress as they provide support and are integrally involved in decision making. A case study is presented to describe a complicated patient scenario and how all involved can develop emotional, moral, and ethical struggles as care is delivered. In clinical cases where nurses feel that their own ethical and moral frameworks are either in conflict with patient, family, or health care provider decisions, or feel that patient and family wishes conflict with one another or the health care system, emotions and distress rise to the surface. In these situations, nurses can advocate for standard practice and to use an ethical framework for decision making, such as the 4-box method, to help decrease moral and ethical struggles as technology continues to advance in health care.
Subject(s)
Critical Illness/psychology , Decision Making/ethics , Adult , Advance Care Planning , Critical Illness/therapy , Emotions , Female , Humans , PregnancyABSTRACT
Abstract: Ferromagnetic alloy materials with designed composition depth profiles provide an efficient route for the control of magnetism at the nanometer length scale. In this regard, cobalt-chromium and cobalt-ruthenium alloys constitute powerful model systems. They exhibit easy-to-tune magnetic properties such as saturation magnetization MS and Curie temperature TC while preserving their crystalline structure over a wide composition range. In order to demonstrate this materials design potential, we have grown a series of graded Co1-xCrx and Co1-wRuw (1010) epitaxial thin films, with x and w following predefined concentration profiles. Structural analysis measurements verify the epitaxial nature and crystallographic quality of our entire sample sets, which were designed to exhibit in-plane c-axis orientation and thus a magnetic in-plane easy axis to achieve suppression of magnetostatic domain generation. Temperature and field-dependent magnetic depth profiles have been measured by means of polarized neutron reflectometry. In both investigated structures, TC and MS are found to vary as a function of depth in accordance with the predefined compositional depth profiles. Our Co1-wRuw sample structures, which exhibit very steep material gradients, allow us to determine the localization limit for compositionally graded materials, which we find to be of the order of 1 nm. The Co1-xCrx systems show the expected U-shaped TC and MS depth profiles, for which these specific samples were designed. The corresponding temperature dependent magnetization profile is then utilized to control the coupling along the film depth, which even allows for a sharp onset of decoupling of top and bottom sample parts at elevated temperatures.
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In this article, I draw from recent developments in the anthropological literatures on kinship and care to complicate and extend analyses of Chinese queer NGOs and AIDS activism. By highlighting the practical, moral, and political dimensions of daily life and work within Chinese queer NGOs, I argue that they constitute what I call "alternative families of care" by serving as important sources of material and emotional support and care for queer men, including increasing numbers of HIV-positive men who have sex with men, in a social climate that is still largely unsupportive and hostile toward both queerness and people living with HIV/AIDS. I also show how HIV/AIDS prevention and care are additionally regarded by many Chinese queer activists as an important political strategy for demonstrating the responsibility of queer men in the face of the AIDS crisis, achieving greater recognition from the government and society, and eventually attaining increased rights, including same-sex marriage.
Subject(s)
Acquired Immunodeficiency Syndrome/prevention & control , Caregivers/psychology , Homosexuality, Male/psychology , Love , Organizations , Acquired Immunodeficiency Syndrome/psychology , Anthropology, Cultural , China , HIV Infections/prevention & control , HIV Infections/psychology , HIV Infections/therapy , Human Rights , Humans , Male , Marriage , Politics , Sexual and Gender Minorities , Social StigmaABSTRACT
Drawing on 17 months of ethnographic fieldwork (2007-2011), this article critically examines the consequences of two global health initiatives (GHIs), the Global Fund and the Gates Foundation, on NGOs engaged in HIV/AIDS prevention and treatment among gay men in northwest China. I argue that a short-term surge in funding provided by GHIs between 2008 and 2010 exacerbated preexisting conflicts between NGOs by promoting a neoliberal process in which the state outsourced public health services to civil society organizations, deliberately encouraging a climate of competition among NGOs. I also show how GHIs encouraged the bureaucratization and medicalization of one grassroots gay NGO, channeling its activities away from broader political and social objectives and compelling the group to develop a narrower and more entrepreneurial emphasis on HIV testing and treatment. This article contributes to a deeper ethnographic understanding of the complex and perhaps unintended consequences of GHIs.
Subject(s)
Global Health/ethnology , HIV Infections/ethnology , Homosexuality, Male/ethnology , Organizations , Adult , China/ethnology , Health Personnel , Humans , MaleABSTRACT
A combination of experiments and numerical modeling was used to study the spatial evolution of the ferromagnetic phase transition in a thin film engineered to have a smooth gradient in exchange strength. Mean-field simulations predict, and experiments confirm, that a 100 nm Ni_{x}Cu_{1-x} alloy film with Ni concentration that varies by 9% as a function of depth behaves predominantly as if composed of a continuum of uncoupled ferromagnetic layers with continuously varying Curie temperatures. A mobile boundary separating ordered and disordered regions emerges as the temperature is increased. We demonstrate continuous control of the boundary position with temperature, and reversible control of the magnetization on both sides of the boundary with the magnetic field.
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BACKGROUND: The Society of Thoracic Surgeons (STS) recommends using gait speed as a marker of frailty to identify cardiac surgery patients at risk for adverse outcomes. However, a single marker of frailty may not provide consistently reliable risk information. We evaluated the impact of frailty and gait speed on patient outcomes after elective cardiac surgery. METHODS: This was a prospective study of 167 older (≥65 years) coronary artery bypass grafting (CABG) and/or valve surgery patients. Patients were assessed using Cardiovascular Health Study (CHS) Frailty Index criteria: weight loss, exhaustion, physical activity, gait speed, and grip strength. RESULTS: Frailty was identified in 39 patients (23%) using CHS criteria. Frail patients had longer median intensive care unit stays (54 vs. 28 h, p = 0.003), longer median length of stay (8 vs. 5 days, p < 0.001), and greater likelihood of STS-defined complications (54% vs. 32%, p = 0.011) and discharge to an intermediate-care facility (45% vs. 12%, p < 0.001) but were not different from nonfrail patients on major outcome, operative mortality, or readmissions. After multivariate adjustment, frail and nonfrail patients were similar on perioperative outcomes. Absolute gait speed and slow gait speed using a cutoff were not related to incidence of STS-defined complications or major outcome in multivariate analyses. However, higher body mass index was correlated with slower gait speed (rs = 0.30, p < 0.001). CONCLUSIONS: The CHS index did not identify "frail" patients at increased risk for adverse outcomes. No relationship was found between gait speed and outcome. There is a need for alternative multidimensional measures to assess frailty in cardiac surgical patients. doi: 10.1111/jocs.12699 (J Card Surg 2016;31:187-194).
Subject(s)
Cardiac Surgical Procedures , Elective Surgical Procedures , Frail Elderly , Walking Speed/physiology , Aged , Aged, 80 and over , Body Mass Index , Cardiac Surgical Procedures/adverse effects , Coronary Artery Bypass , Elective Surgical Procedures/adverse effects , Female , Heart Valves/surgery , Humans , Length of Stay/statistics & numerical data , Male , Multivariate Analysis , Postoperative Complications/epidemiology , Prospective Studies , Risk , Treatment OutcomeABSTRACT
PURPOSE: Some variability in recovery and outcomes after cardiac surgery may be influenced by psychosocial aspects not routinely captured. Preliminary evidence suggests patient expectations impact health status, but there is no specific measure of expectations for cardiac surgery. The purpose of this study was to adapt an expectations scale to cardiac surgery and assess the psychometric properties of the scale. METHODS: Before surgery, 93 patients awaiting non-emergent cardiac surgery completed questionnaires, including the adapted Cardiac Surgery Patient Expectations Questionnaire (C-SPEQ). At 1 year after surgery, 68 patients completed questionnaires. RESULTS: Mean C-SPEQ score was 39.4 ± 9.02, and scores were normally distributed (Cronbach's alpha = 0.86). Higher score indicated negative expectations. Higher presurgery C-SPEQ score was correlated with greater depression (r = 0.32, p = 0.01) and perceived stress (r = 0.36, p = 0.003), but not state anxiety (r = 0.18, p = 0.14), at one-year post-surgery. Higher C-SPEQ was associated with longer recovery time (B = 0.14, p = 0.006) and lower physical HRQL after surgery (B = -0.31, p = 0.005). Higher C-SPEQ was not related to greater odds for perioperative complications (OR 1.01, p = 0.68) or readmissions <30 days (OR 1.05, p = 0.31). C-SPEQ score was not related to survival. CONCLUSIONS: Adaptation of an expectations questionnaire to cardiac surgery patients was successful with acceptable reliability and validity. Negative expectations had a detrimental impact on recovery and HRQL following cardiac surgery but were not related to clinical outcomes. Although focus is mainly on improving clinical outcomes, there are opportunities to improve non-clinical aspects of the patient experience. Presurgical education might better prepare patients, reduce negative expectations, and improve psychosocial outcomes after cardiac surgery.