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1.
Pediatr Cardiol ; 42(8): 1826-1833, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34244822

RESUMO

Patients with congenital heart disease (CHD) that have surgical repair with cardiopulmonary bypass (CPB) reflect a unique population with multiple pulmonary and systemic factors that may contribute to increased alveolar dead space and low cardiac output syndrome. This study aimed to assess and compare changes in the alveolar dead space fraction (AVDSf) in the immediate postoperative period with outcomes in children with CHD who underwent repair on CPB. A single-center retrospective review study of critically ill children with CHD, younger than 18 years of age admitted to the Pediatric Intensive Care Unit (PICU) after undergoing surgical repair on CPB and received invasive mechanical ventilation for at least 24 h. One hundred and two patients were included in the study. Over the first 24 h, mean AVDSf was significantly higher in patients who had longer hospital length of stay (LOS) (> 21 days) p = 0.02, and longer duration of invasive mechanical ventilation (DMV) (> 170 h) p = 0.01. Cross-sectional analyses at 23-24 h revealed that AVDSf > 0.25 predicts mortality and DMV (p = 0.03 and P = 0.02 respectively); however, it did not predict prolonged hospital LOS. For every 0.1 increase in the AVDSf, the odds of mortality, DMV, and hospital LOS increased by 4.9 [95% CI = 1.45-16.60, p = 0.002], 2.06 [95% CI = 1.14-3.71, p = 0.01], and 1.43[95% CI = 0.84-2.45, p = 0.184], respectively. The area under the ROC curve at 23-24 h for AVDSf was 0.868 to predict mortality as an outcome. AVDSf > 0.25 at 23-24 h postoperatively was an independent predictor of mortality with sensitivity and specificity of 83% and 80%, respectively and was superior to other commonly used surrogates of cardiac output. In the immediate postoperative period of pediatric patients with CHD, high AVDSf is associated with longer hospital length of stay and duration of invasive mechanical ventilation. Increased AVDSf values at 23-24 h postoperatively is associated with mortality in patients with CHD exposed to CPB.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Ponte Cardiopulmonar , Criança , Estudos Transversais , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Tempo de Internação , Período Pós-Operatório , Respiração Artificial , Estudos Retrospectivos
2.
Pediatr Emerg Care ; 36(4): e229-e232, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32195981

RESUMO

Shortness of breath and wheezing are common presenting signs for children in the emergency department. In adolescence, it is often due to asthma or lower respiratory tract infections. We present a rare pediatric case of an adolescent with biphasic stridor and progressive exercise-induced shortness of breath who was found to have severe idiopathic subglottic stenosis.


Assuntos
Dispneia/etiologia , Laringoestenose/diagnóstico , Obstrução das Vias Respiratórias/diagnóstico , Anti-Inflamatórios/uso terapêutico , Criança , Dispneia/tratamento farmacológico , Serviço Hospitalar de Emergência , Exercício Físico , Humanos , Laringoestenose/complicações , Laringoestenose/tratamento farmacológico , Masculino , Radiografia , Sons Respiratórios , Espirometria , Resultado do Tratamento
3.
Environ Manage ; 66(3): 407-418, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32556388

RESUMO

Planning for sea level rise (SLR) is a complex process that involves scientific uncertainty and local and regional political tradeoffs. As part of a 6-year transdisciplinary research project in the northern Gulf of Mexico, we conducted focus groups with coastal stakeholders (natural resource managers, community planners, and environmental communicators) to gain a better understanding of their planning and adaptation activities for SLR. This paper reports on participants' perceptions about adaptation and their current adaptation activities and strategies. While stakeholders were concerned about SLR and thought adaptation had challenges, they still shared optimism and a commitment to planning. The findings identify different types of SLR adaptation initiatives in which participants were involved as well as types of perceived barriers to adaptation planning, and major recommended strategies to address them. The paper concludes with a discussion of findings, connections to related SLR adaptation literature, practical implications for coastal resiliency, and directions for future research.


Assuntos
Mudança Climática , Elevação do Nível do Mar , Golfo do México , Humanos , Percepção , Áreas Alagadas
4.
Pediatr Emerg Care ; 32(5): 326-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26221787

RESUMO

An 8-day-old presented in extremis and was subsequently diagnosed with an anomalous left coronary artery from the pulmonary artery. Symptomatic presentation at her young age and atypical echocardiogram findings make this case unique and suggest that demonstration of retrograde coronary flow is unnecessary in symptomatic presentation.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/cirurgia , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Recém-Nascido
5.
Ethiop Med J ; Suppl 2: 27-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25546907

RESUMO

BACKGROUND: In the world emergencies occur everywhere, and each day they consume ressources regardless of whether there are systems capable of achieving good outcomes. Low-income countries suffer the most highest rates of every category of injury--from traffic and the highest rates of acute complications of communicable diseases including tuberculosis, malaria and HIV. OBJECTIVE: To describe the development of pediatrics emergency medicine at Tikur Anbesa Specialized Hospital METHODS: A twinning partnership model was used in developing a pediatric emergency medicine training program helps in development of pediatrics emergency system. RESULTS: Strengthening the capacity of Addis Ababa University (AAU), Tikur Anbessa Hospital (TASH) to provide pediatric emergency medical services through improved organization of the pediatrics emergency department and strengthening of continuing education opportunities for faculty and staff capacity building by this improving quality of care in pediatrics patients in the country. CONCLUSION: The Addis Ababa University, University of Wiscosin and People to People partners intend to continue working together to strengthening and developing effetive systems to deliver quality pediatrics emergency medicine care troughout all regions of Ethiopia.


Assuntos
Medicina de Emergência/métodos , Medicina de Emergência/organização & administração , Hospitais Especializados , Pediatria/métodos , Pediatria/organização & administração , Etiópia , Humanos , Desenvolvimento de Programas
6.
Teach Learn Med ; 25(3): 249-57, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23848333

RESUMO

BACKGROUND: No standardized educational curriculum exists for pediatric sedation practitioners. We sought to describe the curriculum and implementation of a pediatric sedation provider course and assess learner satisfaction with the course curriculum. DESCRIPTION: The course content was determined by formulating a needs assessment using published sedation guidelines, reports of sedation related adverse events, and a survey of sedation practitioners. Students provided feedback regarding satisfaction with the course immediately following the course and 6 months later. EVALUATION: The course consisted of 5 didactic lectures, 1 small-group session, 6 simulation scenarios, a course syllabus, and a written examination. The course was conducted over 1 day at 3 different locations. Sixty-nine students completed the course and were uniformly satisfied with the course curriculum. CONCLUSIONS: A standardized pediatric sedation provider course was developed for sedation practitioners and consisted of a series of lectures and simulation scenarios. Overall satisfaction with the course was positive.


Assuntos
Competência Clínica , Sedação Consciente/normas , Educação Médica Continuada/organização & administração , Pediatria/educação , Currículo , Avaliação Educacional , Retroalimentação , Feminino , Humanos , Masculino , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde
7.
J Appl Physiol (1985) ; 135(1): 94-108, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199780

RESUMO

Ninety-million Americans suffer metabolic syndrome (MetSyn), increasing the risk of diabetes and poor brain outcomes, including neuropathology linked to lower cerebral blood flow (CBF), predominantly in anterior regions. We tested the hypothesis that total and regional CBF is lower in MetSyn more so in the anterior brain and explored three potential mechanisms. Thirty-four controls (25 ± 5 yr) and 19 MetSyn (30 ± 9 yr), with no history of cardiovascular disease/medications, underwent four-dimensional flow magnetic resonance imaging (MRI) to quantify macrovascular CBF, whereas arterial spin labeling quantified brain perfusion in a subset (n = 38/53). Contributions of cyclooxygenase (COX; n = 14), nitric oxide synthase (NOS, n = 17), or endothelin receptor A signaling (n = 13) were tested with indomethacin, NG-monomethyl-L-arginine (L-NMMA), and Ambrisentan, respectively. Total CBF was 20 ± 16% lower in MetSyn (725 ± 116 vs. 582 ± 119 mL/min, P < 0.001). Anterior and posterior brain regions were 17 ± 18% and 30 ± 24% lower in MetSyn; reductions were not different between regions (P = 0.112). Global perfusion was 16 ± 14% lower in MetSyn (44 ± 7 vs. 36 ± 5 mL/100 g/min, P = 0.002) and regionally in frontal, occipital, parietal, and temporal lobes (range 15-22%). The decrease in CBF with L-NMMA (P = 0.004) was not different between groups (P = 0.244, n = 14, 3), and Ambrisentan had no effect on either group (P = 0.165, n = 9, 4). Interestingly, indomethacin reduced CBF more in Controls in the anterior brain (P = 0.041), but CBF decrease in posterior was not different between groups (P = 0.151, n = 8, 6). These data indicate that adults with MetSyn exhibit substantially reduced brain perfusion without regional differences. Moreover, this reduction is not due to loss of NOS or gain of ET-1 signaling but rather a loss of COX vasodilation.NEW & NOTEWORTHY We tested the impact of insulin resistance (IR) on resting cerebral blood flow (CBF) in adults with metabolic syndrome (MetSyn). Using MRI and research pharmaceuticals to study the role of NOS, ET-1, or COX signaling, we found that adults with MetSyn exhibit substantially lower CBF that is not explained by changes in NOS or ET-1 signaling. Interestingly, adults with MetSyn show a loss of COX-mediated vasodilation in the anterior but not posterior circulation.


Assuntos
Síndrome Metabólica , Humanos , Adulto Jovem , ômega-N-Metilarginina , Indometacina , Circulação Cerebrovascular/fisiologia
8.
WMJ ; 121(3): 194-200, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36301645

RESUMO

BACKGROUND: We perceived changes in the frequency of and reasons for admissions to Wisconsin pediatric intensive care units (PICU) during the advent of the COVID-19 pandemic, and we hypothesized that the rates of total, scheduled, and respiratory viral admissions were lower during the first calendar year of the pandemic than would have been predicted by historical admission data. Such findings would reflect important changes in PICU utilization paradigms during the pandemic. There are no descriptions of PICU admission changes in a single American state during the pandemic. METHODS: We compared all Wisconsin PICU admissions during the COVID-19 pandemic in 2020 (the study epoch) to admissions in seasonally matched, growth-adjusted "no-COVID-19" projections generated by time series analysis of all Wisconsin PICU admissions in the previous 5 years (the control epoch). RESULTS: We identified 27,425 PICU admissions with 294,577 associated diagnoses in the study and control epochs. Total admissions were 60 ± 9 week-1 in the study epoch versus 103 ± 4 projected (RR 0.63; 95% CI, 0.59-0.68; P < 0.001). Scheduled admissions were 17 ± 6 week-1 in the study epoch versus 28 ± 3 projected (RR 0.61; 95% CI, 0.55-0.67; P < 0.001). Respiratory viral admissions were 8 ± 5 week-1 in the study epoch versus 19 ± 9 projected (RR 0.40; 95% CI, 0.33-0.48; P < 0.001). Some admission categories experienced dramatic declines (c, respiratory/ear, nose, throat), while others experienced less decline (eg, injury/poisoning/adverse effects) or no significant change (eg, diabetic ketoacidosis). Except cases of COVID-19, no category had significantly increased weekly admissions. There were 104 admissions associated with COVID-19 diagnoses in 2020, 4.3% of the study epoch admissions. CONCLUSIONS: We describe PICU admission changes in the first calendar year of COVID-19, informing health care staffing and service planning, as well as decisions regarding strategies to combat the evolving pandemic.


Assuntos
COVID-19 , Criança , Humanos , COVID-19/epidemiologia , Pandemias , Admissão do Paciente , Wisconsin/epidemiologia , Unidades de Terapia Intensiva Pediátrica , Cuidados Críticos , Estudos Retrospectivos
9.
Respir Care ; 65(10): 1464-1469, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31992665

RESUMO

BACKGROUND: High-flow nasal cannula (HFNC) is commonly used to provide respiratory support to pediatric patients with respiratory failure. Although the use of bronchodilators via HFNC has been described, the feasibility and safety of aerosolized bronchodilator delivery via HFNC are controversial. In this study, we sought to evaluate whether the HFNC system can be used to deliver nebulized bronchodilators at lower gas flow of 2-4 L/min, increase patient comfort, and minimize respiratory therapist (RT) bedside time when compared to traditional interfaces. METHODS: A retrospective chart review of all pediatric subjects who were admitted to the pediatric ICU in a tertiary care children's hospital and required nebulized bronchodilators between December 2017 and June 2018. RESULTS: A total of 205 nebulizations were administered to 28 children; 31% of nebulized bronchodilators were given using a nebulization system integrated into the HFNC. Nebulized treatments resulted in an average increase in heart rate of 9.98 (95% CI 3.72-16.2) beats/min when HFNC was used and 0.64 (95% CI -1.65 to 2.93) beats/min when traditional interfaces were used, a difference of 9.34 (95% CI 2.30-16.4) beats/min (P < .001). RT bedside time was significantly longer for HFNC nebulized treatments (P = .031). Subjective level of comfort was not statically different when nebulized bronchodilators were delivered via HFNC or via traditional interfaces. Length of pediatric ICU stay was not statistically different between subjects who received some aerosol nebulized bronchodilators via HFNC versus those who received all bronchodilators through traditional interfaces (P = .11). CONCLUSIONS: Aerosol bronchodilator delivery using HFNC is feasible at low gas flow (ie, 2-4 L/min). However, the use of HFNC did not improve subjects' comfort, and it increased RT bedside time. Further prospective randomized studies are needed to determine the efficacy and efficiency of aerosol therapy delivered through HFNC and potential patient-oriented outcomes.


Assuntos
Cânula , Síndrome do Desconforto Respiratório , Aerossóis , Broncodilatadores , Criança , Estudos de Viabilidade , Humanos , Nebulizadores e Vaporizadores , Oxigenoterapia , Estudos Retrospectivos
10.
Sci Total Environ ; 648: 1002-1017, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30340249

RESUMO

Climate change such as altered frequency and intensity of storm surge from tropical cyclones can cause saltwater intrusion into coastal aquifers. In this study, a reference SEAWAT model and a diagnostic SEAWAT model are developed to simulate the temporal variation of surficial aquifer total dissolved solids (TDS) concentrations after the occurrence of a storm surge for exploration of the effects of storm surge on the extent of saltwater intrusion into the surficial aquifer in coastal east-central Florida (USA). It is indicated from the simulation results that: (1) rapid infiltration and diffusion of overtopping saltwater resulting from storm surge could cause a significant and rapid increase of TDS concentrations in the surficial aquifer right after the occurrence of storm surge; (2) rapid infiltration of freshwater from rainfall could reduce surficial aquifer TDS concentrations beginning from the second year after the occurrence of storm surge in that the infiltrated rainwater could generate an effective hydraulic barrier to impede further inland migration of saltwater and provide a downgradient freshwater discharge for saltwater dilution and flushing counteracting the effects of storm surge on the extent of saltwater intrusion; and (3) infiltrated rainwater might take approximately eight years to dilute and flush the overwhelming majority of infiltrated saltwater back out to the surrounding waterbodies, i.e., the coastal lagoons and the Atlantic Ocean.

11.
Sci Total Environ ; 630: 211-221, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29477820

RESUMO

Saltwater intrusion (SWI) into root zone in low-lying coastal areas can affect the survival and spatial distribution of various vegetation species by altering plant communities and the wildlife habitats they support. In this study, a baseline model was developed based on FEMWATER to simulate the monthly variation of root zone salinity of a geo-typical area located at the Cape Canaveral Barrier Island Complex (CCBIC) of coastal east-central Florida (USA) in 2010. Based on the developed and calibrated baseline model, three diagnostic FEMWATER models were developed to predict the extent of SWI into root zone by modifying the boundary values representing the rising sea level based on various sea-level rise (SLR) scenarios projected for 2080. The simulation results indicated that the extent of SWI would be insignificant if SLR is either low (23.4cm) or intermediate (59.0cm), but would be significant if SLR is high (119.5cm) in that infiltration/diffusion of overtopping seawater in coastal low-lying areas can greatly increase root zone salinity level, since the sand dunes may fail to prevent the landward migration of seawater because the waves of the rising sea level can reach and pass over the crest under high (119.5cm) SLR scenario.


Assuntos
Mudança Climática , Ecossistema , Monitoramento Ambiental , Água do Mar/análise , Simulação por Computador , Conservação dos Recursos Naturais/métodos , Florida , Previsões , Salinidade , Áreas Alagadas
12.
PLoS One ; 13(10): e0205176, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30312304

RESUMO

Two distinct microtidal estuarine systems were assessed to advance the understanding of the coastal dynamics of sea level rise in salt marshes. A coupled hydrodynamic-marsh model (Hydro-MEM) was applied to both a marine-dominated (Grand Bay, Mississippi) and a mixed fluvial/marine (Weeks Bay, Alabama) system to compute marsh productivity, marsh migration, and potential tidal inundation from the year 2000 to 2100 under four sea level rise scenarios. Characteristics of the estuaries such as geometry, sediment availability, and topography, were compared to understand their role in the dynamic response to sea level rise. The results show that the low sea level rise scenario (20 cm) approximately doubled high-productivity marsh coverage in the marine-dominated estuary by the year 2100 due to an equilibrium between the rates of sea level rise and marsh platform accretion. Under intermediate-low sea level rise (50 cm), high-productivity marsh coverage in the year 2100 increased (doubled in the marine-dominated estuary and a seven-fold increase in the mixed estuary) by expanding into higher lands followed by the creation of interior ponds. The results also indicate that marine-dominated estuaries are vulnerable to collapse as a result of low, relatively uniform topography and lack of sediment sources, whereas mixed estuaries are able to expand due to higher elevations and sediment inputs. The results from the higher sea level rise scenarios (the intermediate-high (120 cm) and high (200 cm)) showed expansion of the bays along with marsh migration to higher land, producing a five-fold increase in wetland coverage for the mixed estuary and virtually no net change for the marine-dominated estuary. Additionally, hurricane storm surge simulations showed that under higher sea level rise scenarios, the marine-dominated estuary demonstrated weaker peak stage attenuation indicating that the marsh's ability to dissipate storm surge is sensitive to productivity changes and bay expansion / marsh loss.


Assuntos
Mudança Climática , Áreas Alagadas , Alabama , Baías , Biomassa , Simulação por Computador , Conservação dos Recursos Naturais , Tempestades Ciclônicas , Estuários , Sedimentos Geológicos , Golfo do México , Hidrodinâmica , Mississippi , Modelos Teóricos , Lagoas
13.
Front Pediatr ; 6: 49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29616202

RESUMO

Pediatric critical care is an important component of reducing morbidity and mortality globally. Currently, pediatric critical care in low middle-income countries (LMICs) remains in its infancy in most hospitals. The majority of hospitals lack designated intensive care units, healthcare staff trained to care for critically ill children, adequate numbers of staff, and rapid access to necessary medications, supplies and equipment. In addition, most LMICs lack pediatric critical care training programs for healthcare providers or certification procedures to accredit healthcare providers working in their pediatric intensive care units (PICU) and high dependency areas. PICU can improve the quality of pediatric care in general and, if properly organized, can effectively treat the severe complications of high burden diseases, such as diarrhea, severe malaria, and respiratory distress using low-cost interventions. Setting up a PICU in a LMIC setting requires planning, specific resources, and most importantly investment in the nursing and permanent medical staff. A thoughtful approach to developing pediatric critical care services in LMICs starts with fundamental building blocks: training healthcare professionals in skills and knowledge, selecting resource appropriate effective equipment, and having supportive leadership to provide an enabling environment for appropriate care. If these fundamentals can be built on in a sustainable manner, an appropriate critical care service will be established with the potential to significantly decrease pediatric morbidity and mortality in the context of public health goals as we reach toward the sustainable development goals.

14.
Expert Rev Respir Med ; 11(12): 945-953, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28994337

RESUMO

INTRODUCTION: High flow nasal cannula (HFNC) is increasingly used in pediatric patients suffering from respiratory failure. In some disease processes, patients may also benefit from aerosol therapy. Therefore, the use of HFNC to deliver aerosolized medications is a convenient and attractive option. Areas covered: This review aims to appraise available evidence concerning the efficiency of aerosol nebulized therapy delivery using HFNC in pediatric patients. Expert commentary: Delivery of aerosol particles is a very complex process and depends on the use of oxygen vs. heliox, nebulizer type and position within the HFNC circuit, patient's breathing effort and pattern, and more importantly cannula size and flow rates. Current in vitro evidence suggests the amount of aerosol delivery is likely to be very low at high flows. Clinical studies are limited in pediatric patients and given the limited clinical data, it is not possible to make recommendations for or against aerosol delivery through HFNC for pediatric patients.


Assuntos
Hélio/uso terapêutico , Nebulizadores e Vaporizadores , Oxigenoterapia/métodos , Oxigênio/uso terapêutico , Insuficiência Respiratória/terapia , Administração por Inalação , Aerossóis , Cânula , Criança , Humanos , Respiração
15.
Am J Trop Med Hyg ; 97(5): 1285-1288, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28820680

RESUMO

The authors describe a multiinstitutional collaborative project to address a gap in global health training by creating a free online platform to share a curriculum for performing procedures in resource-limited settings. This curriculum called PEARLS (Procedural Education for Adaptation to Resource-Limited Settings) consists of peer-reviewed instructional and demonstration videos describing modifications for performing common pediatric procedures in resource-limited settings. Adaptations range from the creation of a low-cost spacer for inhaled medications to a suction chamber for continued evacuation of a chest tube. By describing the collaborative process, we provide a model for educators in other fields to collate and disseminate procedural modifications adapted for their own specialty and location, ideally expanding this crowd-sourced curriculum to reach a wide audience of trainees and providers in global health.


Assuntos
Currículo , Educação em Saúde , Internet , Comportamento Cooperativo , Crowdsourcing , Saúde Global , Recursos em Saúde , Humanos
16.
Sustain Sci ; 11(4): 711-731, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30174740

RESUMO

River deltas all over the world are sinking beneath sea-level rise, causing significant threats to natural and social systems. This is due to the combined effects of anthropogenic changes to sediment supply and river flow, subsidence, and sea-level rise, posing an immediate threat to the 500-1,000 million residents, many in megacities that live on deltaic coasts. The Mississippi River Deltaic Plain (MRDP) provides examples for many of the functions and feedbacks, regarding how human river management has impacted source-sink processes in coastal deltaic basins, resulting in human settlements more at risk to coastal storms. The survival of human settlement on the MRDP is arguably coupled to a shifting mass balance between a deltaic landscape occupied by either land built by the Mississippi River or water occupied by the Gulf of Mexico. We developed an approach to compare 50 % L:W isopleths (L:W is ratio of land to water) across the Atchafalaya and Terrebonne Basins to test landscape behavior over the last six decades to measure delta instability in coastal deltaic basins as a function of reduced sediment supply from river flooding. The Atchafalaya Basin, with continued sediment delivery, compared to Terrebonne Basin, with reduced river inputs, allow us to test assumptions of how coastal deltaic basins respond to river management over the last 75 years by analyzing landward migration rate of 50 % L:W isopleths between 1932 and 2010. The average landward migration for Terrebonne Basin was nearly 17,000 m (17 km) compared to only 22 m in Atchafalaya Basin over the last 78 years (p < 0.001), resulting in migration rates of 218 m/year (0.22 km/year) and <0.5 m/year, respectively. In addition, freshwater vegetation expanded in Atchafalaya Basin since 1949 compared to migration of intermediate and brackish marshes landward in the Terrebonne Basin. Changes in salt marsh vegetation patterns were very distinct in these two basins with gain of 25 % in the Terrebonne Basin compared to 90 % decrease in the Atchafalaya Basin since 1949. These shifts in vegetation types as L:W ratio decreases with reduced sediment input and increase in salinity also coincide with an increase in wind fetch in Terrebonne Bay. In the upper Terrebonne Bay, where the largest landward migration of the 50 % L:W ratio isopleth occurred, we estimate that the wave power has increased by 50-100 % from 1932 to 2010, as the bathymetric and topographic conditions changed, and increase in maximum storm-surge height also increased owing to the landward migration of the L:W ratio isopleth. We argue that this balance of land relative to water in this delta provides a much clearer understanding of increased flood risk from tropical cyclones rather than just estimates of areal land loss. We describe how coastal deltaic basins of the MRDP can be used as experimental landscapes to provide insights into how varying degrees of sediment delivery to coastal deltaic floodplains change flooding risks of a sinking delta using landward migrations of 50 % L:W isopleths. The nonlinear response of migrating L:W isopleths as wind fetch increases is a critical feedback effect that should influence human river-management decisions in deltaic coast. Changes in land area alone do not capture how corresponding landscape degradation and increased water area can lead to exponential increase in flood risk to human populations in low-lying coastal regions. Reduced land formation in coastal deltaic basins (measured by changes in the land:water ratio) can contribute significantly to increasing flood risks by removing the negative feedback of wetlands on wave and storm-surge that occur during extreme weather events. Increased flood risks will promote population migration as human risks associated with living in a deltaic landscape increase, as land is submerged and coastal inundation threats rise. These system linkages in dynamic deltaic coasts define a balance of river management and human settlement dependent on a certain level of land area within coastal deltaic basins (L).

17.
Earths Future ; 4(4): 110-121, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27819012

RESUMO

A mixing model derived from first principles describes the bulk density (BD) of intertidal wetland sediments as a function of loss on ignition (LOI). The model assumes that the bulk volume of sediment equates to the sum of self-packing volumes of organic and mineral components or BD = 1/[LOI/k1 + (1-LOI)/k2], where k1 and k2 are the self-packing densities of the pure organic and inorganic components, respectively. The model explained 78% of the variability in total BD when fitted to 5075 measurements drawn from 33 wetlands distributed around the conterminous United States. The values of k1 and k2 were estimated to be 0.085 ± 0.0007 g cm-3 and 1.99 ± 0.028 g cm-3, respectively. Based on the fitted organic density (k1) and constrained by primary production, the model suggests that the maximum steady state accretion arising from the sequestration of refractory organic matter is ≤ 0.3 cm yr-1. Thus, tidal peatlands are unlikely to indefinitely survive a higher rate of sea-level rise in the absence of a significant source of mineral sediment. Application of k2 to a mineral sediment load typical of East and eastern Gulf Coast estuaries gives a vertical accretion rate from inorganic sediment of 0.2 cm yr-1. Total steady state accretion is the sum of the parts and therefore should not be greater than 0.5 cm yr-1 under the assumptions of the model. Accretion rates could deviate from this value depending on variation in plant productivity, root:shoot ratio, suspended sediment concentration, sediment-capture efficiency, and episodic events.

18.
Water Air Soil Pollut ; 226(3): 68, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25741050

RESUMO

Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean environment indefinitely, decomposing or becoming buried in the sea floor. However, in many cases, they are transported ashore via currents and waves where they pose a concern to coastal recreation activities, the seafood industry and may have negative effects on wildlife. This review summarizes the current state of knowledge on marine tar residue formation, transport, degradation, and distribution. Methods of detection and removal of marine tar residues and their possible ecological effects are discussed, in addition to topics of marine tar research that warrant further investigation. Emphasis is placed on benthic tar residues, with a focus on the remnants of the Deepwater Horizon oil spill in particular, which are still affecting the northern Gulf of Mexico shores years after the leaking submarine well was capped.

19.
Ann Thorac Surg ; 100(6): 2359-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26652536

RESUMO

We present a newborn with heterotaxy features, multiple congenital anomalies, truncus arteriosus with long segment tracheal stenosis, and a left pulmonary artery sling. The patient had complete neonatal repair with slide tracheoplasty and repair of the left pulmonary artery sling with anterior translocation of the pulmonary artery. The truncus was repaired with a transventricular ventricular septal defect closure with a patch and right ventricle to pulmonary artery conduit. Complete repair of complex cardiac neonatal lesions with critical tracheal stenosis is feasible and should be the strategy of choice in these complex patients.


Assuntos
Síndrome de Heterotaxia/cirurgia , Artéria Pulmonar/anormalidades , Estenose Traqueal/cirurgia , Persistência do Tronco Arterial/cirurgia , Síndrome de Heterotaxia/complicações , Síndrome de Heterotaxia/diagnóstico , Humanos , Recém-Nascido , Masculino , Estenose Traqueal/complicações , Estenose Traqueal/diagnóstico , Persistência do Tronco Arterial/complicações , Persistência do Tronco Arterial/diagnóstico
20.
Pediatr Crit Care Med ; 4(2): 206-13, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12749654

RESUMO

OBJECTIVES: To compare survival of pediatric umbilical cord blood and bone marrow transplant recipients requiring admission to a pediatric intensive care unit for mechanical ventilation and to determine the effect of organ dysfunction on outcome. DESIGN: Retrospective chart review. SETTING: Tertiary care referral center for pediatric stem cell transplants. PATIENTS: All children 0-18 yrs old admitted to the pediatric intensive care unit for mechanical ventilation after receiving a stem cell transplant. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data were collected from medical records of 86 patients who received a stem cell transplant and were subsequently admitted to the pediatric intensive care unit for mechanical ventilation. Demographic data were collected at the time of intubation, and physiologic data were collected at 6 hrs and 96 hrs after intubation. The pediatric intensive care unit, hospital, and 2-yr survival rates for umbilical cord blood transplant recipients were 37%, 25%, and 19%, respectively. The survival rates for bone marrow transplant recipients were 47%, 32%, and 21% for the same time periods. Umbilical cord blood and bone marrow transplant recipients with hepatic dysfunction had a significantly worse outcome, as did patients admitted for respiratory failure or sepsis. CONCLUSIONS: Pediatric recipients of an umbilical cord blood transplant who subsequently required mechanical ventilation had lower pediatric intensive care unit and hospital survival rates compared with patients receiving bone marrow transplantation. Survival at 2 yrs for umbilical cord blood transplant and bone marrow transplant patients was similar. Predictors of outcome for all stem cell transplant recipients requiring mechanical ventilation included pediatric intensive care unit diagnosis requiring intubation and hepatic function. Predictors of outcome can be identified shortly after intubation in pediatric stem cell transplant recipients and may aid in therapeutic decision making and family counseling.


Assuntos
Transplante de Medula Óssea , Sangue Fetal/transplante , Mortalidade Hospitalar , Respiração Artificial , Transplante de Células-Tronco , Taxa de Sobrevida , Criança , Pré-Escolar , Feminino , Humanos , Unidades de Terapia Intensiva Pediátrica , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
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