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Human beings are predisposed to identifying false patterns in statistical noise, a likely survival advantage during our evolutionary development. Moreover, humans seem to prefer "positive" results over "negative" ones. These two cognitive features lay a framework for premature adoption of falsely positive studies. Added to this predisposition is the tendency of journals to "overbid" for exciting or newsworthy manuscripts, incentives in both the academic and publishing industries that value change over truth and scientific rigour, and a growing dependence on complex statistical techniques that some reviewers do not understand. The purpose of this article is to describe the underlying causes of premature adoption and provide recommendations that may improve the quality of published science.
RéSUMé: Les êtres humains ont tendance à identifier de fausses corrélations dans le bruit de fond statistique, ce qui nous a probablement conféré un avantage en matière de survie au cours de notre développement évolutionnaire. De plus, l'être humain semble préférer les résultats « positifs ¼ aux résultats « négatifs ¼. Ces deux caractéristiques cognitives posent un cadre expliquant l'adoption hâtive d'études faussement positives. À cette prédisposition s'ajoutent la tendance des revues à « surenchérir ¼ pour les manuscrits prometteurs ou notables, les incitatifs tant dans les milieux académiques qu'éditoriaux, qui préfèrent le changement à la vérité et à la rigueur scientifique, et une dépendance croissante à l'égard de techniques statistiques complexes que certains réviseurs ne comprennent pas. L'objectif de cet article est de décrire les causes sous-jacentes d'adoption prématurée de nouveautés et de proposer des recommandations afin d'améliorer la qualité de la science publiée.
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Anestesia , Editoração , HumanosRESUMO
BACKGROUND: Arteriovenous fistulae (AVF) are the preferred access for hemodialysis, however, there continues to be limited data guiding the surgical management of primary dialysis access creation in elderly end-stage renal disease patients. METHODS: This is an 8-year retrospective institutional study evaluating the operative and clinical characteristics of patients 70 years or above who underwent primary, first-ever, AVF or arteriovenous graft (AVG) creation. RESULTS: There was no overall significant difference in AVF and AVG primary (P = 0.127) and secondary (P = 0.870) patency. AVG had higher graft loss secondary to infection (P = 0.0002) and thrombosis (P = 0.0213). Survival was less than 50% at 2 years for AVF and AVG patients. An equal number of AVF and AVG patients who died had functional access at the time of death (P = 1.0000) with more AVG patients using their graft (initiating dialysis) before death (P = 0.0118). CONCLUSIONS: Elderly patient patency rates for AVF and AVG are satisfactory and support surgical access creation; however, overall 2-year survival is low. An equal number of AVF and AVG patients died with functioning surgical access, however, more AVG patients initiated dialysis and successfully used their access. Accordingly, special consideration needs to be given with regard to estimated timing until dialysis and predicted patient longevity. Delaying access creation until dialysis is needed and proceeding with AVG creation appears to be justified.
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Derivação Arteriovenosa Cirúrgica , Diálise Renal , Insuficiência Renal Crônica/terapia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/instrumentação , Derivação Arteriovenosa Cirúrgica/mortalidade , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Infecções Relacionadas à Prótese/microbiologia , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/mortalidade , Estudos Retrospectivos , Fatores de Risco , Stents/efeitos adversos , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
BACKGROUND: Despite almost 2 decades of experience with cadaveric vein, there remains a paucity of available data regarding the role of cadaveric vein in hemodialysis, specifically with regard to outcomes and patency. Observations from our own experience have suggested that cadaveric vein grafts (CVGs) provide good outcomes, particularly in patients with recurrent access failure. Accordingly, this study aims to comparatively examine patency, access-related outcomes, and survival in patients undergoing placement of arteriovenous fistulae (AVF), polytetrafluorethylene (PTFE) grafts, and CVGs. METHODS: This is a single institution 11-year retrospective case series evaluating the outcomes of 210 patients who underwent creation of AVF, PTFE grafts, and CVGs for hemodialysis access. Patients in the AVF (n = 70) and arteriovenous graft (AVG; n = 70) groups were matched to the CVG (n = 70) group by age, gender, and access location. Postoperative end points for all groups included primary and assisted patency, cause of access abandonment, and survival. RESULTS: Patients were matched for age (P = 0.8707), gender (P = 0.6958), and access location and no significant differences existed between groups. AVF showed superior primary patency at 30 days, 1 year (64.3%, P < 0.0001) and 2 years (54.3%, P = 0.0091) in comparison to both AVG and CVG. AVG had reduced patency at 30 days (84.3%, P = 0.0009), 1 year (50.0%, P < 0.0001), and 2 years (32.9%, P = 0.0001) in comparison to AVF and CVG groups. Overall, AVF had the highest patency at all-time points followed, respectively by CVG and AVG. No significant difference existed between AVF and CVG groups with regard to secondary patency at 30 days (98.6% vs. 97.1%, P = 1.0000), 1 year (81.4% vs. 78.6%, P = 0.6749), and 2 years (68.6% vs. 51.4%, P = 0.0573). AVG patients had decreased survival (years) after access creation in comparison to AVF and CVG groups (P = 0.0003). CONCLUSIONS: Our findings lend further support to the use of cadaveric vein for hemodialysis access surgery. As demonstrated through this comparative study, CVGs are capable of providing favorable results with regard to patency, access longevity, and patient survival. These current outcomes indicate that cadaveric vein is a sustainable alternative to PTFE for hemodialysis access surgery and should be accordingly considered for difficult access patients.
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Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Prótese Vascular , Politetrafluoretileno , Diálise Renal , Insuficiência Renal Crônica/terapia , Idoso , Cadáver , Criopreservação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Critical care transport medicine (CCTM) teams are playing an increasing role in the care of patients in cardiogenic shock requiring mechanical circulatory support devices. Hence, it is important that CCTM providers are familiar with the pathophysiology of cardiogenic shock, the role of mechanical circulatory support, and the management of these devices in the transport environment. The intra-aortic balloon pump is a widely used and accessible cardiac support device capable of increasing cardiac output and reducing work on the left ventricle through diastolic augmentation and counterpulsation. This article reviews essential CCTM-based considerations for patients supported by intra-aortic balloon pump, including indications for placement, mechanics and physiology, potential issues during transport, and associated complications.
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Importance: Understanding how social policies shape health is a national priority, especially in the context of the COVID-19 pandemic. Objective: To understand the association between politically motivated changes to Nebraska's Supplemental Nutrition Assistance Program (SNAP) policy and public health measures during the COVID-19 pandemic. Design, Setting, and Participants: This cross-sectional study used synthetic control methods to estimate the association of Nebraska's decision to reject emergency allotments for the SNAP with food security and hospital capacity indicators. A counterfactual for Nebraska was created by weighting data from the rest of the US. State-level changes in Nebraska between March 2020 and March 2021 were included. Data were acquired from the Census Bureau's Household Pulse Survey on individual food security and mental health indicators and from the US Centers for Disease Control and Prevention on hospital-level capacity indicators. Data analysis occurred between October 2022 and June 2023. Intervention: The rejection of additional SNAP funds for low-income households in Nebraska from August to November 2020. Main Outcomes and Measures: Food insecurity and inpatient bed use indicators (ie, inpatient beds filled, inpatient beds filled by patients with COVID-19, and inpatients with COVID-19). Results: The survey data of 1â¯591â¯006 respondents from May 2020 to November 2020 was analyzed, and 24â¯869 (1.56%) lived in Nebraska. Nebraska's population was composed of proportionally more White individuals (mean [SD], 88.70% [0.29%] vs 78.28% [0.26%]; P < .001), fewer individuals who made more than $200â¯000 in 2019 (4.20% [0.45%] vs 5.22% [0.12%]; P < .001), and more households sized 1 to 3 (63.41% [2.29%] vs 61.13% [1.10%); P = .03) compared with other states. Nebraska's rejection of additional funding for SNAP recipients was associated with increases in food insecurity (raw mean [SD] difference 1.61% [1.30%]; relative difference, 19.63%; P = .02), percentage of inpatient beds filled by patients with COVID-19 (raw mean [SD] difference, 0.19% [1.55%]; relative difference, 3.90%; P = .02), and percentage of inpatient beds filled (raw mean [SD] difference, 2.35% [1.82%]; relative difference, 4.10%; P = .02). Conclusions and Relevance: In this cross-sectional study, the association between social policy, food security, health, and public health resources was examined, and the rejection of emergency allotments in Nebraska was associated with increased food insecurity. Additionally, this intervention was associated with an increased rate of hospitalizations for COVID-19 and non-COVID-19 causes.
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COVID-19 , Assistência Alimentar , Humanos , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Hospitalização , Hospitais , Segurança AlimentarRESUMO
Introduction: Oxidative phosphorylation is an essential feature of Animalian life. Multiple adaptations have developed to protect against hypoxia, including hypoxia-inducible-factors (HIFs). The major role of HIFs may be in protecting against oxidative stress, not the preservation of high-energy phosphates. The precise mechanism(s) of HIF protection is not completely understood. Materials and Methods: To better understand the role of hypoxia-inducible-factor-1, we exposed heart/myocardium cells (H9c2) to both normoxia and hypoxia, as well as cobalt chloride (prolyl hydroxylase inhibitor), echniomycin (HIF inhibitor), A2P (anti-oxidant), and small interfering RNA to beclin-1. We measured cell viability, intracellular calcium and adenosine triphosphate, NADP/NADPH ratios, total intracellular reactive oxidative species levels, and markers of oxidative and antioxidant levels measured. Results: Hypoxia (1%) leads to increased intracellular Ca2+ levels, and this response was inhibited by A2P and echinomycin (ECM). Exposure of H9c2 cells to hypoxia also led to an increase in both mRNA and protein expression for Cav 1.2 and Cav 1.3. Exposure of H9c2 cells to hypoxia led to a decrease in intracellular ATP levels and a sharp reduction in total ROS, SOD, and CAT levels. The impact of hypoxia on ROS was reversed with HIF-1 inhibition through ECM. Exposure of H9c2 cells to hypoxia led to an increase in Hif1a, VEGF and EPO protein expression, as well as a decrease in mitochondrial DNA. Both A2P and ECM attenuated this response to varying degrees. Conclusion: Hypoxia leads to increased intracellular Ca2+, and inhibition of HIF-1 attenuates the increase in intracellular Ca2+ that occurs with hypoxia. HIF-1 expression leads to decreased adenosine triphosphate levels, but the role of HIF-1 on the production of reactive oxidative species remains uncertain. Anti-oxidants decrease HIF-1 expression in the setting of hypoxia and attenuate the increase in Ca2+ that occurs during hypoxia (with no effect during normoxia). Beclin-1 appears to drive autophagy in the setting of hypoxia (through ATG5) but not in normoxia. Additionally, Beclin-1 is a powerful driver of reactive oxidative species production and plays a role in ATP production. HIF-1 inhibition does not affect autophagy in the setting of hypoxia, suggesting that there are other drivers of autophagy that impact beclin-1.
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Importance: Administrative records indicate that more than half of the 80 million Medicaid enrollees identify as belonging to a racial and ethnic minority group. Despite this, disparities within the Medicaid program remain understudied. For example, we know of no studies examining racial differences in Medicaid spending, a potential measure of how equitably state resources are allocated. Objectives: To examine whether and to what extent there are differences in health care spending and utilization between Black and White enrollees in Medicaid. Design Setting and Participants: This cross-sectional study used calendar year 2016 administrative data from 3 state Medicaid programs and included 1 966 689 Black and White Medicaid enrollees. Analyses were performed between January 28, 2021, and October 18, 2021. Exposures: Self-reported race. Main Outcomes and Measures: Rates and racial differences in health care spending and utilization (including Healthcare Effectiveness Data and Information Set [HEDIS] access measures). Results: Of 1 966 689 Medicaid adults and children (mean [SD] age, 20.3 [17.1] years; 1 119 136 [56.9%] female), 867 183 (44.1%) self-identified as non-Hispanic Black and 1 099 506 (55.9%) self-identified as non-Hispanic White. Results were adjusted for age, sex, Medicaid eligibility category, zip code, health status, and usual source of care. On average, annual spending on Black adult (19 years or older) Medicaid enrollees was $317 (95% CI, $259-$375) lower than White enrollees, a 6% difference. Among children (18 years or younger), annual spending on Black enrollees was $256 (14%) lower (95% CI, $222-$290). Adult Black enrollees also had 19.3 (95% CI, 16.78-21.84), or 4%, fewer primary care encounters per 100 enrollees per year compared with White enrollees. Among children, the differences in primary care utilization were larger: Black enrollees had 90.1 (95% CI, 88.2-91.8) fewer primary care encounters per 100 enrollees per year compared with White enrollees, a 23% difference. Black enrollees had lower utilization of most other services, including high-value prescription drugs, but higher emergency department use and rates of HEDIS preventive screenings. Conclusions and Relevance: In this cross-sectional study of US Medicaid enrollees in 3 states, Black enrollees generated lower spending and used fewer services, including primary care and recommended care for acute and chronic conditions, but had substantially higher emergency department use. While Black enrollees had higher rates of HEDIS preventive screenings, ensuring equitable access to all services in Medicaid must remain a national priority.
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Etnicidade , Medicaid , Adulto , Criança , Estudos Transversais , Feminino , Gastos em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Grupos Minoritários , Estados Unidos , Adulto JovemRESUMO
INTRODUCTION: Cryopreserved vein allografts (cadaveric vein) have emerged as an option for arteriovenous graft reconstruction; however, indications for their use in hemodialysis access remains to be clearly defined. Observations from our own experience have suggested that cadaveric vein grafts (CVGs) provide good outcomes, particularly in patients with a history of infection, recurrent access failure and advanced age. METHODS: This is a 10-year retrospective study. Primary outcomes were (1) to identify characteristics specific to this patient population and (2) to better define indications for use of cadaveric vein in hemodialysis access creation. RESULTS: Indications for creation of CVGs included patient history of either active or recent infection (41.5%), recurrent access failure (43.4%) or surgeon preference secondary to patients' advanced age (9.4%). Observed primary patency rates were 84.9% (30 days), 22.6% (1 year) and 16.0% (2 years). Secondary patency was 93.4% (30 days), 66.0% (1 year) and 52.8% (2 years). Patient death was the highest cause of graft abandonment (52.9%) followed by thrombosis (19.1%), infection (11.7%) and rupture (11.7%). CVG patency at the time of patient death was 83.7%. CONCLUSIONS: The rates of both primary and secondary patency in CVGs are highly comparable to the reported patency rates of polytetrafluoroethylene (PTFE) grafts and allow for lifelong maintenance of dialysis access. Our observed outcome suggests that CVGs should be considered for patients needing vascular access in the presence of infection. CVGs may likewise be viable alternatives to PTFE grafts in the elderly and patients with limited access options.