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1.
Proc Natl Acad Sci U S A ; 120(6): e2214205120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36724258

RESUMO

Tissue flow during morphogenesis is commonly driven by local constriction of cell cortices, which is caused by the activation of actomyosin contractility. This can lead to long-range flows due to tissue viscosity. However, in the absence of cell-intrinsic polarized forces or polarity in forces external to the tissue, these flows must be symmetric and centered around the region of contraction. Polarized tissue flows have been previously demonstrated to arise from the coupling of such contractile flows to points of increased friction or adhesion to external structures. However, we show with experiments and modeling that the onset of polarized tissue flow in early Drosophila morphogenesis occurs independent of adhesion and is instead driven by a geometric coupling of apical actomyosin contractility to tissue curvature. Particularly, the onset of polarized flow is driven by a mismatch between the position of apical myosin activation and the position of peak curvature at the posterior pole of the embryo. Our work demonstrates how genetic and geometric information inherited from the mother interact to create polarized flow during embryo morphogenesis.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Actomiosina/metabolismo , Proteínas de Drosophila/metabolismo , Miosinas/metabolismo , Morfogênese/fisiologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero
2.
Phys Rev Lett ; 130(5): 058202, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800465

RESUMO

Biological cells can actively tune their intracellular architecture according to their overall shape. Here we explore the rheological implication of such coupling in a minimal model of a dense cellular material where each cell exerts an active mechanical stress along its axis of elongation. Increasing the active stress amplitude leads to several transitions. An initially hexagonal crystal motif is first destabilized into a solid with anisotropic cells whose shear modulus eventually vanishes at a first critical activity. Increasing activity beyond this first critical value, we find a re-entrant transition to a regime with finite hexatic order and finite shear modulus, in which cells arrange according to a rhombile pattern with periodically arranged rosette structures. The shear modulus vanishes again at a third threshold beyond which spontaneous tissue flows and topological defects of the nematic cell shape field arise. Flow and stress fields around the defects agree with active nematic theory, with either contractile or extensile signs, as also observed in several epithelial tissue experiments.


Assuntos
Forma Celular , Estresse Mecânico , Reologia
3.
Pediatr Crit Care Med ; 24(9): 775-781, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37260321

RESUMO

OBJECTIVES: Report on the use of two statewide Medical Operations Coordination Centers (MOCCs) to manage a rapid surge in pediatric acute and critical care patient needs. DESIGN: Brief report. SETTING: The states of Washington and Oregon during the pediatric respiratory surge in November 2022/December 2022 which overwhelmed existing pediatric acute and critical care hospital capacity. PATIENTS: Pediatric patients requiring hospitalization in Washington and Oregon. INTERVENTIONS: Adaptations to the use of two existing statewide MOCCs to provide pediatric patient load balancing through surveillance, modifications of existing referral agreements, coordinated expansion of resources, activation of regional crisis standards of care, and integration of pediatric critical care physicians from Harborview Medical Center as subject matter experts (SMEs). MEASUREMENTS AND MAIN RESULTS: The Washington and Oregon MOCCs managed 183 pediatric requests from hospitals unable to transfer pediatric patients between November 1, 2022, and December 14, 2022. Sixteen percent of requests were for children younger than 3 months and 37% were for children between 3 months and 1 year; most had acute viral respiratory disease. Requests for children older than 13 years old were primarily intentional drug ingestions. Fifty-eight percent were for critically ill children and 17% originated from critical access hospitals. Washington's SMEs were utilized in nearly a quarter of cases with the disposition changing in 38% of these. CONCLUSIONS: Washington and Oregon statewide MOCCs have leveraged centralized coordination to effectively load balance a surge in pediatric patients which has overwhelmed existing pediatric hospital resources. Centralized coordination and surveillance informed pediatric hospitals and policy makers of unmet clinical needs and facilitated rapid expansion of clinical capacity and modifications to referral processes. Integration of pediatric SMEs enabled efficient triage of these resources. MOCCs provide an adaptable centralized resource for addressing surge and have been effective in managing overwhelmed pediatric hospital resources in Washington and Oregon.


Assuntos
Hospitalização , Hospitais Pediátricos , Criança , Humanos , Estados Unidos , Adolescente , Triagem , Washington , Encaminhamento e Consulta , Capacidade de Resposta ante Emergências
4.
Proc Natl Acad Sci U S A ; 117(24): 13541-13551, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32467168

RESUMO

Within developing embryos, tissues flow and reorganize dramatically on timescales as short as minutes. This includes epithelial tissues, which often narrow and elongate in convergent extension movements due to anisotropies in external forces or in internal cell-generated forces. However, the mechanisms that allow or prevent tissue reorganization, especially in the presence of strongly anisotropic forces, remain unclear. We study this question in the converging and extending Drosophila germband epithelium, which displays planar-polarized myosin II and experiences anisotropic forces from neighboring tissues. We show that, in contrast to isotropic tissues, cell shape alone is not sufficient to predict the onset of rapid cell rearrangement. From theoretical considerations and vertex model simulations, we predict that in anisotropic tissues, two experimentally accessible metrics of cell patterns-the cell shape index and a cell alignment index-are required to determine whether an anisotropic tissue is in a solid-like or fluid-like state. We show that changes in cell shape and alignment over time in the Drosophila germband predict the onset of rapid cell rearrangement in both wild-type and snail twist mutant embryos, where our theoretical prediction is further improved when we also account for cell packing disorder. These findings suggest that convergent extension is associated with a transition to more fluid-like tissue behavior, which may help accommodate tissue-shape changes during rapid developmental events.


Assuntos
Forma Celular , Drosophila/crescimento & desenvolvimento , Animais , Anisotropia , Drosophila/citologia , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Epitélio/metabolismo , Miosina Tipo II/genética , Miosina Tipo II/metabolismo
5.
Soft Matter ; 18(13): 2672-2683, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35311835

RESUMO

Phase separation can drive spatial organization of multicomponent mixtures. For instance in developing animal embryos, effective phase separation descriptions have been used to account for the spatial organization of different tissue types. Similarly, separation of different tissue types is also observed in stem cell aggregates, where the emergence of a polar organization can mimic early embryonic axis formation. Here, we describe such aggregates as deformable two-phase fluid droplets, which are suspended in a fluid environment (third phase). Using hybrid finite-volume Lattice-Boltzmann simulations, we numerically explore the out-of-equilibrium routes that can lead to the polar equilibrium state of such a droplet. We focus on the interplay between spinodal decomposition and advection with hydrodynamic flows driven by interface tensions, which we characterize by a Peclet number Pe. Consistent with previous work, for large Pe the coarsening process is generally accelerated. However, for intermediate Pe we observe long-lived, strongly elongated droplets, where both phases form an alternating stripe pattern. We show that these "croissant" states are close to mechanical equilibrium and coarsen only slowly through diffusive fluxes in an Ostwald-ripening-like process. Finally, we show that a surface tension asymmetry between both droplet phases leads to transient, rotationally symmetric states whose resolution leads to flows reminiscent of Marangoni flows. Our work highlights the importance of advection for the phase separation process in finite, deformable systems.

6.
Soft Matter ; 18(29): 5410-5425, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35822259

RESUMO

Disordered spring networks are a useful paradigm to examine macroscopic mechanical properties of amorphous materials. Here, we study the elastic behavior of under-constrained spring networks, i.e. networks with more degrees of freedom than springs. While such networks are usually floppy, they can be rigidified by applying external strain. Recently, an analytical formalism has been developed to predict the scaling behavior of the elastic network properties close to this rigidity transition. Here we numerically show that these predictions apply to many different classes of spring networks, including phantom triangular, Delaunay, Voronoi, and honeycomb networks. The analytical predictions further imply that the shear modulus G scales linearly with isotropic stress T close to the rigidity transition. However, this seems to be at odds with recent numerical studies suggesting an exponent between G and T that is smaller than one for some network classes. Using increased numerical precision and shear stabilization, we demonstrate here that close to the transition a linear scaling, G ∼ T, holds independent of the network class. Finally, we show that our results are not or only weakly affected by finite-size effects, depending on the network class.

7.
Eur Phys J E Soft Matter ; 45(1): 4, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35038043

RESUMO

Vertex models describe biological tissues as tilings of polygons. In standard vertex models, the tissue dynamics result from a balance between isotropic stresses, which are associated with the bulk of the cells, and tensions associated with cell-cell interfaces. However, in this framework it is less obvious how to describe anisotropic stresses arising from the bulk of cells. In epithelia, such bulk anisotropic stresses could arise for instance through medial myosin fluctuations. Two recent publications-Tlili et al. (Proc Natl Acad Sci USA 116(51):25430-25439, 2019) and Comelles et al. (eLife 10:e57730, 2021)-have proposed different schemes to implement bulk anisotropic stresses in vertex models. Here we show that while both schemes transform in the same way under affine deformations, they lead to significantly different tissue dynamics. Our results are consistent with the interpretation that the Tilli et al. scheme describes bulk stresses that are uniform within each cell, while the Comelles et al. scheme corresponds to non-uniform bulk stresses. Finally, we wondered whether a standard vertex model can be fully expressed in terms of bulk cellular stresses alone. We find that, in general, neither scheme can mimic the vertex forces created by cell-cell interface tensions.


Assuntos
Modelos Biológicos , Anisotropia , Epitélio
8.
Proc Natl Acad Sci U S A ; 116(14): 6560-6568, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30894489

RESUMO

We present an approach to understand geometric-incompatibility-induced rigidity in underconstrained materials, including subisostatic 2D spring networks and 2D and 3D vertex models for dense biological tissues. We show that in all these models a geometric criterion, represented by a minimal length [Formula: see text], determines the onset of prestresses and rigidity. This allows us to predict not only the correct scalings for the elastic material properties, but also the precise magnitudes for bulk modulus and shear modulus discontinuities at the rigidity transition as well as the magnitude of the Poynting effect. We also predict from first principles that the ratio of the excess shear modulus to the shear stress should be inversely proportional to the critical strain with a prefactor of 3. We propose that this factor of 3 is a general hallmark of geometrically induced rigidity in underconstrained materials and could be used to distinguish this effect from nonlinear mechanics of single components in experiments. Finally, our results may lay important foundations for ways to estimate [Formula: see text] from measurements of local geometric structure and thus help develop methods to characterize large-scale mechanical properties from imaging data.

9.
J Nurs Care Qual ; 36(2): 112-116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33259469

RESUMO

BACKGROUND: The COVID-19 pandemic resulted in the need for hospitals to plan for a potential "surge" of COVID-19 patients. PROBLEM: Prior to the onset of the COVID-19 pandemic, our hospital adult acute care capacity ranged 90% to 100%, and a potential hospital surge was projected for Oregon that would exceed existing capacity. APPROACH: A multidisciplinary team with stakeholders from nursing leadership, nursing units, nurse-led case management, and physicians from hospital medicine was convened to explore the conversion of an ambulatory surgical center to overflow patient acute care capacity. OUTCOMES: A protocol was rapidly created and implemented, ultimately transferring 12 patients to an ambulatory surgery unit. CONCLUSIONS: This project highlighted the ability for stakeholders and innovators to work together in an interprofessional, multidisciplinary way to rapidly create an overflow unit. While this innovation was designed to address COVID-19, the lessons learned can be applied to any other emerging infectious disease or acute care capacity crisis.


Assuntos
COVID-19/epidemiologia , COVID-19/terapia , Planejamento Hospitalar/organização & administração , Inovação Organizacional , Equipe de Assistência ao Paciente/organização & administração , Humanos , Oregon/epidemiologia
10.
Proc Natl Acad Sci U S A ; 114(48): 12663-12668, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29138312

RESUMO

Collective cell migration is a highly regulated process involved in wound healing, cancer metastasis, and morphogenesis. Mechanical interactions among cells provide an important regulatory mechanism to coordinate such collective motion. Using a self-propelled Voronoi (SPV) model that links cell mechanics to cell shape and cell motility, we formulate a generalized mechanical inference method to obtain the spatiotemporal distribution of cellular stresses from measured traction forces in motile tissues and show that such traction-based stresses match those calculated from instantaneous cell shapes. We additionally use stress information to characterize the rheological properties of the tissue. We identify a motility-induced swim stress that adds to the interaction stress to determine the global contractility or extensibility of epithelia. We further show that the temporal correlation of the interaction shear stress determines an effective viscosity of the tissue that diverges at the liquid-solid transition, suggesting the possibility of extracting rheological information directly from traction data.


Assuntos
Movimento Celular/fisiologia , Forma Celular/fisiologia , Células Epiteliais/fisiologia , Modelos Biológicos , Animais , Fenômenos Biomecânicos , Células Epiteliais/citologia , Humanos , Morfogênese/fisiologia , Transição de Fase , Reologia , Estresse Mecânico , Viscosidade , Cicatrização/fisiologia
11.
Semin Cell Dev Biol ; 67: 161-169, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27496334

RESUMO

In multi-cellular organisms, morphogenesis translates processes at the cellular scale into tissue deformation at the scale of organs and organisms. To understand how biochemical signaling regulates tissue form and function, we must understand the mechanical forces that shape cells and tissues. Recent progress in developing mechanical models for tissues has led to quantitative predictions for how cell shape changes and polarized cell motility generate forces and collective behavior on the tissue scale. In particular, much insight has been gained by thinking about biological tissues as physical materials composed of cells. Here we review these advances and discuss how they might help shape future experiments in developmental biology.


Assuntos
Citoesqueleto/metabolismo , Drosophila melanogaster/metabolismo , Células Epiteliais/metabolismo , Mecanotransdução Celular , Morfogênese/fisiologia , Peixe-Zebra/metabolismo , Animais , Fenômenos Biomecânicos , Comunicação Celular , Divisão Celular , Movimento Celular , Forma Celular , Citoesqueleto/ultraestrutura , Drosophila melanogaster/crescimento & desenvolvimento , Embrião não Mamífero , Células Epiteliais/citologia , Modelos Biológicos , Estresse Mecânico , Asas de Animais/citologia , Asas de Animais/metabolismo , Peixe-Zebra/crescimento & desenvolvimento
12.
Anesthesiology ; 130(4): 530-540, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30601218

RESUMO

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Electromagnetic interference from monopolar electrosurgery may disrupt implantable cardioverter defibrillators.Current management recommendations by the American Society of Anesthesiologists and Heart Rhythm Society are based on expert clinical opinion since there is a paucity of data regarding the risk of electromagnetic interference to implantable cardioverter defibrillators during surgery. WHAT THIS ARTICLE TELLS US THAT IS NEW: With protocolized electrosurgery dispersive electrode positioning in patients with implantable cardioverter defibrillators, the risk of clinically meaningful electromagnetic interference was 7% in above-the-umbilicus noncardiac surgery and 0% in below-the-umbilicus surgery. In cardiac surgery, clinically meaningful electromagnetic interference with use of an underbody dispersive electrode was 29%.Despite protocolized dispersive electrode positioning, the risk of electromagnetic interference in above-the-umbilicus surgery is high, supporting recommendations to suspend antitachycardia therapy when monopolar electrosurgery is used above the umbilicus.With protocolized dispersive electrode positioning, the risk of electromagnetic interference in below-the-umbilicus surgery is negligible, implying that suspending antitachycardia therapy might be unnecessary in these cases.With an underbody dispersive electrode, the risk of electromagnetic interference in cardiac surgery is high. BACKGROUND: The goal of this study was to determine the occurrence of intraoperative electromagnetic interference from monopolar electrosurgery in patients with an implantable cardioverter defibrillator undergoing surgery. A protocolized approach was used to position the dispersive electrode. METHODS: This was a prospective cohort study including 144 patients with implantable cardioverter defibrillators undergoing surgery between May 2012 and September 2016 at an academic medical center. The primary objectives were to determine the occurrences of electromagnetic interference and clinically meaningful electromagnetic interference (interference that would have resulted in delivery of inappropriate antitachycardia therapy had the antitachycardia therapy not been programmed off) in noncardiac surgeries above the umbilicus, noncardiac surgeries at or below the umbilicus, and cardiac surgeries with the use of an underbody dispersive electrode. RESULTS: The risks of electromagnetic interference and clinically meaningful electromagnetic interference were 14 of 70 (20%) and 5 of 70 (7%) in above-the-umbilicus surgery, 1 of 40 (2.5%) and 0 of 40 (0%) in below-the-umbilicus surgery, and 23 of 34 (68%) and 10 of 34 (29%) in cardiac surgery. Had conservative programming strategies intended to reduce the risk of inappropriate antitachycardia therapy been employed, the occurrence of clinically meaningful electromagnetic interference would have been 2 of 70 (2.9%) in above-the-umbilicus surgery and 3 of 34 (8.8%) in cardiac surgery. CONCLUSIONS: Despite protocolized dispersive electrode positioning, the risks of electromagnetic interference and clinically meaningful electromagnetic interference with surgery above the umbilicus were high, supporting published recommendations to suspend antitachycardia therapy whenever monopolar electrosurgery is used above the umbilicus. For surgery below the umbilicus, these risks were negligible, implying that suspending antitachycardia therapy is likely unnecessary in these patients. For cardiac surgery, the risks of electromagnetic interference and clinically meaningful electromagnetic interference with an underbody dispersive electrode were high. Conservative programming strategies would not have eliminated the risk of clinically meaningful electromagnetic interference in either noncardiac surgery above the umbilicus or cardiac surgery.


Assuntos
Desfibriladores Implantáveis/normas , Eletrodos Implantados/normas , Fenômenos Eletromagnéticos , Eletrocirurgia/normas , Marca-Passo Artificial/normas , Adulto , Idoso , Desfibriladores Implantáveis/efeitos adversos , Eletrodos Implantados/efeitos adversos , Eletrocirurgia/instrumentação , Eletrocirurgia/métodos , Feminino , Cardiopatias/fisiopatologia , Cardiopatias/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial/efeitos adversos
13.
Soft Matter ; 14(17): 3397-3403, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29667689

RESUMO

Vertex models are a popular approach to simulating the mechanical and dynamical properties of dense biological tissues, describing the tissue as a network of polygons. Recently a class of two-dimensional vertex models was shown to exhibit a disordered rigidity transition controlled by the preferred cellular geometry, which was subsequently echoed by experimental findings. An attractive variant of these models uses a Voronoi tessellation to describe the cells, which reduces the number of degrees of freedom as compared the original vertex model. The Voronoi model was also endowed with a non-equilibrium model of cellular motility, leading to rich, glassy behavior. This glassy behavior was suggested to be inextricably linked to an underlying jamming transition. We test this conjecture, exploring the low-effective-temperature limit of the 2D Voronoi model by studying cell trajectories from detailed dynamical simulations in combination with rigidity measurements of energy-minimized disordered cell configurations. We find that the zero-temperature limit of this model has no unjamming transition. We show that this absence of an unjamming transition is intimately linked to the marginality of the model, i.e. the fact that the constraints imposed on cell areas and perimeters precisely balance the number of degrees of freedom in the model. Our work suggests that constraint counting arguments are useful to understand rigidity in a broad class of models of dense biological tissues.


Assuntos
Modelos Biológicos , Movimento Celular
14.
BMC Cardiovasc Disord ; 18(1): 71, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703158

RESUMO

BACKGROUND: There is a lack of data on anticoagulation requirements during ablation of atrial fibrillation (AF). This study compares different oral anticoagulation (OAC) strategies to evaluate risk of bleeding and thromboembolic complications. METHODS: We conducted a single-centre study in patients undergoing left atrial ablation of AF. Three groups were defined: 1) bridging: interrupted vitamin-K-antagonists (VKA), INR ≤2, and bridging with heparin; 2) VKA: uninterrupted VKA and INR of > 2; 3) DOAC: uninterrupted direct oral anticoagulants. Bleeding complications, thromboembolic events and peri-procedural heparin doses were assessed. RESULTS: In total, 780 patients were documented. At 48 h, major complications were more common in the bridging group compared to uninterrupted VKA and DOAC groups (OR: 3.42, 95% CI: 1.29-9.10 and OR: 3.01, 95% CI: 1.19-7.61), largely driven by differences in major pericardial effusion (OR: 4.86, 95% CI: 1.56-15.99 and OR: 4.466, 95% CI, 1.52-13.67) and major vascular events (OR: 2.92, 95% CI: 0.58-14.67 and OR: 9.72, 95% CI: 1.00-94.43). Uninterrupted VKAs and DOACs resulted in similar odds of major complications (overall OR: 1.14, 95% CI: 0.44-2.92), including cerebrovascular events (OR: 1.21, 95% CI: 0.27-5.45). However, whereas only TIAs were observed in DOAC and bridging groups, strokes also occurred in the VKA group. Rates of minor complications (pericardial effusion, vascular complications, gastrointestinal hemorrhage) and major/minor groin hemorrhage were similar across groups. CONCLUSION: Our dataset illustrates that uninterrupted VKA and DOAC have a better risk-benefit profile than VKA bridging. Bridging was associated with a 4.5× increased risk of complications and should be avoided, if possible.


Assuntos
Anticoagulantes/administração & dosagem , Fibrilação Atrial/cirurgia , Ablação por Cateter , Vitamina K/antagonistas & inibidores , Administração Oral , Idoso , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Esquema de Medicação , Feminino , Alemanha , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Fatores de Tempo , Resultado do Tratamento
15.
BMC Cardiovasc Disord ; 17(1): 135, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28545407

RESUMO

BACKGROUND: Effective treatment of paroxysmal atrial fibrillation (AF) is essential for reducing the risk of stroke and heart failure. Cryoballoon (CB) ablation has been developed as an alternative to the use of radiofrequency (RF) energy for electrical isolation of the pulmonary veins. Herein, we provide long-term data regarding the efficacy of CB ablation in comparison to RF. METHODS: FreezeAF was a randomised non-inferiority study comparing CB ablation with RF ablation for the treatment of patients with drug-refractory paroxysmal AF. Procedural success for the long-term follow-up (30 months) was defined as freedom from AF with an absence of persistent complications. RESULTS: Of the 315 patients that were randomised and received catheter ablation, 292 (92.7%) completed the 30-month follow-up (147 in the RF group and 145 in the CB group). The baseline characteristics of the RF and CB groups were similar. Single-procedure success was achieved by 40% of patients in the RF group and 42% of the CB group (p < 0.001 for non-inferiority). When including re-do procedures in the analysis, the multiple procedure success rate was 72% in the RF group and 76% in the CB group. CONCLUSION: The data provide long-term evidence that CB ablation is non-inferior to RF ablation, with high proportions of patients reporting freedom from AF 30 months after the index procedure. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00774566 ; first registered October 16, 2008; first patient included October 20, 2008.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Criocirurgia , Veias Pulmonares/cirurgia , Irrigação Terapêutica , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Criocirurgia/efeitos adversos , Criocirurgia/instrumentação , Intervalo Livre de Doença , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Veias Pulmonares/fisiopatologia , Recidiva , Irrigação Terapêutica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
16.
Anesth Analg ; 125(2): 477-482, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28504990

RESUMO

INTRODUCTION: Serious complications are common during the intensive care of postoperative cardiac surgery patients. Some of these complications may be influenced by communication during the process of handover of care from the operating room to the intensive care unit (ICU) team. A structured transfer of care process may reduce the rate of communication errors and perioperative complications. METHODS: We hypothesized that a collaborative, comprehensive, structured handover of care from the intraoperative team to the ICU team would reduce a specific set of postoperative complications. We tested this hypothesis by developing and introducing a comprehensive multidisciplinary transfer of care process. We measured patient outcomes before and after the intervention using a linkage between 2 care databases: an Anesthesia Information Management System and a critical care complication registry database. RESULTS: There were 1127 total postoperative cardiac surgery admissions during the study period, 550 before and 577 after the intervention. There was no statistical difference between overall complications before and after the intervention (P = .154). However, there was a statistically significant reduction in preventable complications after the intervention (P = .023). DISCUSSION: The main finding of this investigation is that the introduction of a collaborative, comprehensive transfer of care process from the operating room to the ICU was associated with patients suffering fewer preventable complications.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiologia/organização & administração , Transferência da Responsabilidade pelo Paciente , Idoso , Anestesiologia , Sistemas Computacionais , Continuidade da Assistência ao Paciente/organização & administração , Cuidados Críticos , Bases de Dados Factuais , Feminino , Humanos , Período Intraoperatório , Masculino , Erros Médicos , Pessoa de Meia-Idade , Salas Cirúrgicas/organização & administração , Admissão do Paciente , Equipe de Assistência ao Paciente , Avaliação de Resultados da Assistência ao Paciente , Período Perioperatório , Complicações Pós-Operatórias/prevenção & controle , Período Pós-Operatório , Sistema de Registros , Estudos Retrospectivos , Software , Recursos Humanos
17.
Anesth Analg ; 125(1): 58-65, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28319519

RESUMO

BACKGROUND: Economic, personnel, and procedural challenges often complicate and interfere with efficient and safe perioperative care of patients with cardiovascular implantable electronic devices (CIEDs). In the context of a process improvement initiative, we created and implemented a comprehensive anesthesiologist-run perioperative CIED service to respond to all routine requests for perioperative CIED consultations at a large academic medical center. This study was designed to determine whether this new care model was associated with improved operating room efficiency, reduced institutional cost, and adequate patient safety. METHODS: We included patients with a CIED and a concurrent cohort of patients with the same eligibility criteria but without a CIED who underwent first-case-of-the-day surgery during the periods between February 1, 2008, and August 17, 2010 (preintervention) and between March 4, 2012, and August 1, 2014 (postintervention). The primary end point was delay in first-case-of-the day start time. We used multiple linear regression to compare delays in start times during the preintervention and postintervention periods and to adjust for potential confounders. A patient safety database was queried for CIED-related complications. Cost analysis was based on labor minutes saved and was calculated using nationally published administrative estimates. RESULTS: A total of 18,148 first-case surgical procedures were performed in 15,100 patients (preintervention period-7293 patients and postintervention period-7807 patients). Of those, 151 (2.1%) patients had a CIED in the preintervention period, and 146 (1.9%) had a CIED in the postintervention period. After adjustment for imbalances in baseline characteristics (age, American Society of Anesthesiologists physical status, and surgical specialty), the difference in mean first-case start delay between the postintervention and preintervention periods in the cohort of patients with a CIED was -16.7 minutes (95% confidence interval [CI], -26.1 to -7.2). The difference in mean delay between the postintervention and preintervention periods in the cohort without a CIED was -4.7 minutes (95% CI, -5.4 to -3.9). There were 3 CIED-related adverse events during the preintervention period and none during the postintervention period. Based on reduction in first-case start delay, the intervention was associated with cost savings (estimated institutional savings $14,102 annually, or $94.06 per CIED patient), with a return on investment ratio of 2.18 over the course of the postintervention period. CONCLUSIONS: Based on our experience, specially trained anesthesiologists can provide efficient and safe perioperative care for patients with CIEDs. Other centers may consider implementing a similar strategy as our specialty adopts the perioperative surgical home model.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Desfibriladores Implantáveis , Avaliação de Processos e Resultados em Cuidados de Saúde , Marca-Passo Artificial , Assistência Perioperatória/métodos , Centros Médicos Acadêmicos , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Cardíacos/economia , Sistema Cardiovascular , Estudos de Coortes , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Salas Cirúrgicas , Segurança do Paciente , Período Perioperatório , Medição de Risco , Fatores de Tempo
18.
Circulation ; 132(14): 1311-9, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26283655

RESUMO

BACKGROUND: There is a lack of data on the comparative efficacy and procedural safety of open irrigated radiofrequency (RF) and cryoballoon catheter (CB) ablation for pulmonary vein isolation in patients with paroxysmal atrial fibrillation. METHODS AND RESULTS: In a prospective, noninferiority study, 315 patients were randomly assigned to RF (n=159) or CB (n=156) ablation. The primary end point was freedom from atrial arrhythmia with absence of persistent complications. Patients were largely comparable between groups with more vascular disease in the RF group (8.2% versus 2.6% for CB; P=0.028). The primary end point at 12 months was achieved by 70.7% with RF and 73.6% with CB (multiple procedure success), including 31 redo procedures in each group (19.5% of RF versus 19.9% of CB; P=0.933). For the intention-to-treat population, noninferiority of CB was revealed for the predefined inferiority margin (risk difference, 0.029; 95% confidence interval, -0.074 to 0.132; P<0.001). Rates at 6 months were 63.1% and 64.1% for the RF and CB groups (single procedure success), and noninferiority was confirmed (risk difference, 0.010; 95% confidence interval, -0.097 to 0.116; P=0.002). Periprocedural complications for the index procedure were more frequent in the CB group (5.0% RF, 12.2% CB; P=0.022) with a significant difference in phrenic nerve palsies (0% RF, 5.8% CB; P=0.002). CONCLUSION: This large, prospective, randomized, controlled study demonstrates noninferiority of CB ablation versus RF ablation for treating patients with paroxysmal atrial fibrillation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00774566.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Criocirurgia/métodos , Veias Pulmonares/cirurgia , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Doenças Cardiovasculares/epidemiologia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Terapia Combinada , Comorbidade , Criocirurgia/efeitos adversos , Criocirurgia/instrumentação , Diabetes Mellitus/epidemiologia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Imageamento Tridimensional , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/epidemiologia , Derrame Pericárdico/etiologia , Nervo Frênico/lesões , Hemorragia Pós-Operatória/induzido quimicamente , Estudos Prospectivos , Medição de Risco , Tamanho da Amostra , Trombofilia/tratamento farmacológico , Trombofilia/etiologia , Resultado do Tratamento
20.
Curr Opin Crit Care ; 22(6): 578-583, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27811560

RESUMO

PURPOSE OF REVIEW: The purpose is to review the current application of extracorporeal life support (ECLS) in trauma patients. In addition, programmatic development is described. RECENT FINDINGS: ECLS use is increasing among trauma patients. Several recent studies among trauma patients report survival rates of 65-79%. Despite the high bleeding risk, extracorporeal membrane oxygenation (ECMO) may be safely implemented in trauma patients based on a strict protocol-driven policy. Early implementation may improve overall outcomes. Alternative anticoagulants and heparin free periods may be well tolerated in trauma patients at high risk of hemorrhage. SUMMARY: ECMO is becoming a more routine option in severely injured trauma patients that develop severe respiratory failure. Well tolerated implementation and program development is possible among regional trauma centers. Although clinical knowledge gaps exist, ECMO is a promising treatment in this high-risk population.


Assuntos
Estado Terminal , Oxigenação por Membrana Extracorpórea/métodos , Insuficiência Respiratória/terapia , Ferimentos e Lesões/complicações , Anticoagulantes/uso terapêutico , Oxigenação por Membrana Extracorpórea/tendências , Heparina/uso terapêutico , Humanos , Insuficiência Respiratória/etiologia , Choque Hemorrágico/terapia , Centros de Traumatologia , Resultado do Tratamento
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