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1.
Pediatr Cardiol ; 34(2): 390-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22872019

RESUMO

Although parvovirus B19 (PVB19) currently is the most common cause of viral myocarditis, limited pediatric data exist. Whereas other viruses infect cardiomyocytes, PVB19 targets coronary endothelium, leading to myocardial ischemia and dysfunction. A retrospective review investigated patients with polymerase chain reaction (PCR)-verified PVB19 myocarditis at Texas Children's Hospital and Arkansas Children's Hospital (January 2005 to August 2008). The primary end points of the study were transplant-free survival and circulatory collapse (death, mechanical support, or transplantation). For the 19 patients identified (age, 6 months to 15 years), the most common presenting symptoms were respiratory and gastrointestinal. At admission, all the patients demonstrated ventricular dysfunction requiring inotropic support (median ejection fraction, 24 %; median left ventricle end-diastolic diameter [LVEDD] z-score, 4.6). Whereas T-wave abnormalities were common, ST elevation was evident in five patients (two died and three required transplantation). Serum B-type natrietic peptide was elevated in all 12 patients tested (range, 348-8,058 pg/ml), and troponin I was high in 7 of 9 patients (range, 0.04-14.5 ng/ml). Of the 15 patients with circulatory collapse, nine received mechanical support, eight underwent successful transplantation, and five died. Only six patients (32 %) experienced transplant-free survival, and five patients had full recovery of function at discharge. In the transplant-free survival group, ST changes on presenting electrocardiography were less likely (p = 0.03), and the admission LVEDD z-score tended to be lower (3.3 vs 5.6; p = 0.08). In children, PVB19 myocarditis causes significant mortality and morbidity. Although mechanical intervention can support patients in the initial stage of decompensated heart failure, patients with PVB19 myocarditis often demonstrate persistent dysfunction requiring medical therapy and transplantation.


Assuntos
DNA Viral/análise , Miocardite/epidemiologia , Infecções por Parvoviridae/epidemiologia , Parvovirus B19 Humano/genética , Adolescente , Arkansas/epidemiologia , Criança , Pré-Escolar , Eletrocardiografia , Feminino , Seguimentos , Coração/virologia , Humanos , Lactente , Masculino , Morbidade/tendências , Miocardite/diagnóstico , Miocardite/virologia , Miocárdio/patologia , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/virologia , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Texas/epidemiologia
2.
Pediatr Crit Care Med ; 13(1): 47-52, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21516054

RESUMO

OBJECTIVES: To describe the experience with extracorporeal membrane oxygenation support for intractable primary arrhythmias in newborns and infants. DESIGN: Retrospective study. SETTING: A tertiary care pediatric hospital. PATIENTS: Patients younger than 1 yr supported with extracorporeal membrane oxygenation for primary cardiac arrhythmias were identified from the institutional extracorporeal membrane oxygenation registry. INTERVENTIONS: Extracorporeal membrane oxygenation support. MEASUREMENTS AND MAIN RESULTS: Clinical characteristics and outcomes were investigated for patients with primary cardiac arrhythmia supported with extracorporeal membrane oxygenation. Outcomes investigated were time from initiation of extracorporeal membrane oxygenation support to arrhythmia control, duration of extracorporeal membrane oxygenation support, and results of interventions performed while supported with extracorporeal membrane oxygenation. We summarized the independent categorical and continuous variables using frequencies, percentages, and medians and ranges, respectively. Extracorporeal membrane oxygenation support was used in nine patients for rescue therapy for primary tachyarrhythmia and bradycardia. The primary arrhythmias were: focal atrial tachycardia (n = 2); reentrant supraventricular tachycardia (n = 3); junctional ectopic tachycardia (n = 2); and congenital complete atrioventricular block (n = 2) patients. Seven patients presented with severe hemodynamic compromise, with six patients requiring extracorporeal cardiopulmonary resuscitation. All patients required extracorporeal membrane oxygenation within 24 hrs of initial presentation. Balloon atrial septostomy was performed in three patients and ablation was performed in two patients. Sinus rhythm was achieved in all reentrant supraventricular tachycardia and rate control was established in both patients with focal atrial tachycardia and in one patient with junctional ectopic tachycardia while using extracorporeal membrane oxygenation support. All patients survived to hospital discharge, and median follow-up for the cohort was 5 yrs. There was one late death; all survivors had good overall and neurologic outcomes. CONCLUSIONS: The requirement of extracorporeal membrane oxygenation support in newborns and infants with intractable arrhythmia is rare. Extracorporeal membrane oxygenation support does potentially carry morbidity; however, to prevent arrhythmia-related mortality, extracorporeal membrane oxygenation support and/or extracorporeal cardiopulmonary resuscitation should be considered in the management of hemodynamically unstable primary arrhythmias as an emergent lifesaving procedure.


Assuntos
Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/terapia , Oxigenação por Membrana Extracorpórea/métodos , Bloqueio Cardíaco/congênito , Arritmias Cardíacas/mortalidade , Reanimação Cardiopulmonar/métodos , Estudos de Coortes , Estado Terminal/mortalidade , Estado Terminal/terapia , Feminino , Seguimentos , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/mortalidade , Bloqueio Cardíaco/terapia , Mortalidade Hospitalar , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
3.
J Heart Lung Transplant ; 24(6): 645-51, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15949722

RESUMO

BACKGROUND: Transplant coronary artery disease (TCAD) limits survival in heart transplant recipients; however, its incidence in children is unknown. The purpose of this study was to determine the angiographic incidence of TCAD, potential risk factors, and outcomes in a large pediatric cohort. METHODS: From January 1993 to December 1, a total of 1,222 children, aged newborn to 17 years, underwent primary cardiac transplantation at 20 institutions. A total of 2,049 coronary angiograms were performed in 751 patients. All angiograms were graded for coronary disease and results were submitted to the Pediatric Heart Transplant Study database. We analyzed time-related freedom from graded severity and events from coronary disease, and we examined risk factors. RESULTS: The incidence of angiographic abnormalities at 1, 3, and 5 years was 2%, 9%, and 17%, respectively; however, moderate-to-severe disease occurred in only 6% at 5 years, compared with 15% in the adult transplant database (p <0.0001). The major risk factors were older recipient and donor age. Two or more episodes of rejection in the 1st year correlated with coronary disease (p = 0.05). Overall freedom from graft loss caused by primary TCAD was 99%, 96%, and 91% at 1, 5, and 9 years after heart transplantation, respectively. Death or graft loss occurred within 2 years of diagnosis in patients with severe disease; 24% of patients with any coronary disease died within 2 years. CONCLUSIONS: The incidence of TCAD in children is smaller than the incidence in adults, but increases with age. Graft loss is infrequent in children; however, severe coronary disease correlates with poor prognosis.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Transplante de Coração/efeitos adversos , Adolescente , Criança , Pré-Escolar , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Seguimentos , Sobrevivência de Enxerto , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Resultado do Tratamento
4.
ASAIO J ; 51(5): 670-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16322739

RESUMO

A 14-year-old boy with repaired transposition of the great arteries and ventricular septal defect presented with atrial flutter and severe congestive heart failure. Despite successful cardioversion and optimal medical therapy, the patient deteriorated and was supported with extracorporeal membrane oxygenation (ECMO). Two days after initiating ECMO support, we implanted the DeBakey VAD Child ventricular assist device (MicroMed Technology, Inc., Houston, TX) under the Humanitarian Device Exemption program. Later, he was able to pursue normal daily activities including physical rehabilitation and ambulation in the hospital. After 56 days, he underwent a successful cardiac transplantation. After 3 months, he had good cardiac function and no evidence of rejection. The DeBakey VAD Child device is a valuable option for cardiac support as a bridge to transplantation.


Assuntos
Oxigenação por Membrana Extracorpórea/instrumentação , Transplante de Coração , Coração Auxiliar , Implantação de Prótese , Adolescente , Flutter Atrial/terapia , Desenho de Equipamento , Oxigenação por Membrana Extracorpórea/métodos , Seguimentos , Insuficiência Cardíaca/terapia , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
5.
J Heart Lung Transplant ; 22(7): 770-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12873545

RESUMO

BACKGROUND: Since 1990, extracorporeal membrane oxygenation (ECMO) has been used as a bridge to cardiac transplantation in 47 patients. METHODS: A review of the ECMO database, approved by the Arkansas Children's Hospital institutional review board, forms the basis of this report. We made statistical comparison using Fisher's exact probability testing. The ECMO circuitry was a roller occlusion pump with computer-assisted perfusion system technology. RESULTS: Thirty-two (68%) patients underwent transcatheter septostomy for cardiac decompression. Diagnosis at presentation was either congenital heart disease (CHD, n = 15) or cardiomyopathy (n = 32). Ages ranged from 1 day to 22 years old (median, 18 months old), and weight ranged from 2.9 to 100 kg (median, 10 kg). The average duration of support was 242 hours (range, 22-1078 hours). Overall long-term survival was 47%, with 16 (34%) patients successfully bridged to cardiac transplantation (of which 9 [56%] survived) and 13 (28%) successfully weaned from ECMO. Patients undergoing ECMO after cardiotomy had 31% survival. Survival was improved significantly (p < 0.02) in patients with cardiomyopathy (59%) vs those with CHD (20%). Patients with cardiomyopathy underwent 8 transplantations with 7 survivors (88%), whereas in the CHD group, there were 8 transplantations with only 2 survivors (25%), p < 0.05. Sub-analysis of the cardiomyopathy group revealed that patients with acute cardiomyopathy in association with documented viral illness had a 75% chance of being weaned from ECMO without undergoing transplantation. Complications during ECMO occurred in 45% of survivors and were more frequent in non-survivors. Infectious complications were most frequent, followed by neurologic complications, technical ECMO problems, and renal insufficiency. CONCLUSIONS: Patients with cardiomyopathy has a better prognosis than did those with CHD when using ECMO as a bridge to transplantation or survival. Complications are significant and increase with the duration of support. Extracorporeal membrane oxygenation for salvage and subsequent transplantation in this high-risk group of patients requires critical review. Alternative support options must be developed in the pediatric population that will allow improved outcomes, comparable with outcomes achieved in the adult population.


Assuntos
Oxigenação por Membrana Extracorpórea , Transplante de Coração , Adolescente , Adulto , Arkansas , Cardiomiopatias/mortalidade , Cardiomiopatias/cirurgia , Criança , Proteção da Criança , Pré-Escolar , Feminino , Seguimentos , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Ventrículos do Coração/anormalidades , Ventrículos do Coração/transplante , Humanos , Lactente , Bem-Estar do Lactente , Recém-Nascido , Masculino , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento , Listas de Espera
6.
Ann Thorac Surg ; 96(5): 1727-33, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23998407

RESUMO

BACKGROUND: Cerebrovascular events (CVEs) are common among children supported with the Berlin EXCOR (Berlin Heart GmbH, Berlin, Germany) ventricular assist device (VAD). Given the high incidence of CVEs associated with this device, we sought to describe our institutional experience in incrementally reducing CVEs in children supported with the Berlin EXCOR VAD. METHODS: We collected pertinent data on 39 consecutive patients who underwent Berlin EXCOR VAD implantation at a single center. Frequency of CVEs was described in risk per implantation, per day, and in reference to the time of therapeutic anticoagulation. Risk factors were analyzed for association with CVEs. RESULTS: Of the initial 39 Berlin EXCOR VAD implantations, 16 CVEs occurred in 12 patients. The incidence of CVEs decreased with institutional experience per patient (R(2) = 0.6909, p = 0.007) and per patient-day (R(2) = 0.8051, p = 0.002). CVEs occurred more frequently before therapeutic anticoagulation targets were achieved (4.1%/day) compared with after therapeutic anticoagulation targets were achieved (0.9%/day; p = 0.044). CONCLUSIONS: Incidence of CVEs decreased with institutional experience. The risk of CVE is highest in the immediate postoperative period before therapeutic anticoagulation is achieved. Further studies are warranted in pediatric patients supported with the Berlin EXCOR VAD to confirm our findings in a larger cohort.


Assuntos
Coração Auxiliar/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Criança , Pré-Escolar , Humanos , Incidência , Desenho de Prótese , Estudos Retrospectivos , Acidente Vascular Cerebral/prevenção & controle
7.
Science ; 335(6064): 53-9, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22116030

RESUMO

Several states and countries have adopted targets for deep reductions in greenhouse gas emissions by 2050, but there has been little physically realistic modeling of the energy and economic transformations required. We analyzed the infrastructure and technology path required to meet California's goal of an 80% reduction below 1990 levels, using detailed modeling of infrastructure stocks, resource constraints, and electricity system operability. We found that technically feasible levels of energy efficiency and decarbonized energy supply alone are not sufficient; widespread electrification of transportation and other sectors is required. Decarbonized electricity would become the dominant form of energy supply, posing challenges and opportunities for economic growth and climate policy. This transformation demands technologies that are not yet commercialized, as well as coordination of investment, technology development, and infrastructure deployment.

8.
J Am Coll Cardiol ; 70(4): 495-503, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28669447
10.
J Heart Lung Transplant ; 30(7): 755-60, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21419658

RESUMO

BACKGROUND: The survival benefit of heart transplantation in adult heart failure is greatest for the sickest patients and negligible for patients not requiring inotropic or mechanical support. We hypothesized a similar survival benefit of heart transplantation for childhood cardiomyopathies with heart failure. METHODS: A merged data set of children registered in both the Pediatric Cardiomyopathy Registry and the Pediatric Heart Transplant Study was used to assess differences in mortality before and after transplant in patients with different levels of heart failure severity. Severity was scored 2 if mechanical ventilatory or circulatory support was required, 1 if intravenous inotropes were required, or 0 if no support was required. RESULTS: For 332 eligible children, 12-month mortality after listing was 9% for those with a severity score of 0 (n = 105), 16% with a score of 1 (n = 118), and 26% with a score of 2 (n = 109; p = 0.002) with a 3%, 8%, and 20% mortality with severity scores at listing of 0, 1, and 2, respectively, occurring before transplant. Patients listed with a score of 0 frequently deteriorated: 50% received an allograft or died before transplant with severity scores of 1 or 2. The risk of deterioration increased with previous surgery (relative risk, 3.84; p = 0.03) in the short-term and with lower left ventricular mass z-score at time of presentation (relative risk, 1.74; p = 0.003) in the longer-term. CONCLUSION: Pediatric cardiomyopathy patients who require high levels of support receive a survival benefit from heart transplantation that is not shared by patients not requiring intravenous inotropic or mechanical support.


Assuntos
Cardiomiopatias/mortalidade , Insuficiência Cardíaca/complicações , Transplante de Coração , Índice de Gravidade de Doença , Listas de Espera/mortalidade , Circulação Assistida , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Criança , Pré-Escolar , Progressão da Doença , Feminino , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Transplante de Coração/mortalidade , Humanos , Masculino , Estudos Prospectivos , Respiração Artificial , Risco , Taxa de Sobrevida , Resultado do Tratamento
11.
J Thorac Cardiovasc Surg ; 139(1): 170-3, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20106363

RESUMO

OBJECTIVE: Early postoperative hyperlactatemia is seen in some children after surgical repair of secundum atrial septal defect despite apparently normal cardiac output. The objective of the study was to investigate the intraoperative risk factors for hyperlactatemia in patients undergoing atrial septal defect repair. METHODS AND RESULTS: A retrospective review of 68 consecutive patients who underwent isolated atrial septal defect repair at Arkansas Children's Hospital between January 2001 and March 2006 was performed. Perioperative factors in the high lactate group (lactate >3 mmol/L, n = 26) were compared with those in the low lactate group (n = 42). Early hyperlactatemia was seen in 38% of the cohort. The high lactate group showed significantly lower weight-indexed cardiopulmonary bypass flow rate (101 + or - 6.5 mL/kg(-1)/min(-1) vs 131 + or - 6.0 mL/kg(-1)/min(-1), P = .0013), oxygen delivery during cardiopulmonary bypass (mean 12.7 + or - 0. 7 mL/kg(-1)/min(-1) vs 17.0 + or - 1 mL/kg(-1)/min(-1), P = .0009), and higher postoperative glucose (191 + or - 8.6 mg/dL vs 151 + or - 5.4 mg/dL, P = .003) compared with the LL group. Multivariate logistic regression analysis showed that weight-indexed cardiopulmonary bypass flow rate (P = .007) and average mean arterial blood pressure during cardiopulmonary bypass (P = .009) were independent risk factors for postoperative hyperlactatemia. Cardiopulmonary bypass flow rate less than 100 mL/kg(-1)/min(-1) was associated with an odds ratio of 7.67 (95% confidence interval, 1.28-45.86; P = .026) for postoperative hyperlactatemia. CONCLUSION: Lower weight-indexed cardiopulmonary bypass flow rate is an independent risk factor for early postoperative hyperlactatemia in children after atrial septal defect repair.


Assuntos
Ponte Cardiopulmonar , Comunicação Interatrial/cirurgia , Lactatos/sangue , Adolescente , Anestesia Geral , Criança , Pré-Escolar , Humanos , Lactente , Complicações Intraoperatórias , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco
12.
J Am Coll Cardiol ; 54(2): 160-5, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19573734

RESUMO

OBJECTIVES: We sought to evaluate the outcomes and identify risk factors for mortality after heart transplantation (HT) for congenital heart disease (CHD) in infants, children, and adults. BACKGROUND: CHD is considered a risk factor for mortality after HT, yet this unique group of patients represents a spectrum of complexity. METHODS: There were 488 patients transplanted for CHD from the combined Pediatric Heart Transplant Study (1993 to 2002, n = 367) and the Cardiac Transplant Registry Database (1990 to 2002, n = 121) who were analyzed. RESULTS: The median age at HT was 12.4 years. Primary diagnosis included single ventricle (36%), d-transposition of the great arteries (12%), right ventricular outflow tract lesions (10%), l-transposition of the great arteries (8%), ventricular/atrial septal defects (8%), left ventricular outflow obstruction (8%), and other (18%). Ninety-three percent of patients had at least 1 operation before HT. Survival at 3 months post-HT was significantly worse in CHD patients versus children with cardiomyopathy, but not adults with cardiomyopathy (86%, 94%, and 91%, respectively). There was no difference in conditional 3-month survival among the 3 groups. Five-year survival was 80%. Risk factors for early mortality were older recipient age, older donors with longer ischemic times, and pre-HT Fontan operations. Predicted survival in Fontan patients was lower (77% and 70% at 1 and 5 years) versus non-Fontan patients (88% and 81% at 1 and 5 years). Risk factors for constant phase mortality included younger recipient age, higher transpulmonary gradient, cytomegalovirus mismatch at HT, and earlier classical Glenn operation. CONCLUSIONS: Patients undergoing transplantation for CHD have a good late survival if they survive the early post-operative period. Risk factors for reduced survival are older age at transplant and a previous Fontan operation.


Assuntos
Angiografia Coronária/métodos , Ecocardiografia/métodos , Cardiopatias Congênitas/mortalidade , Transplante de Coração/métodos , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Procedimentos Cirúrgicos Cardíacos/métodos , Criança , Pré-Escolar , Seguimentos , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
13.
Environ Sci Technol ; 42(10): 3501-7, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18546680

RESUMO

We update a previously presented Linear Programming (LP) methodology for estimating state level costs for reducing CO2 emissions from existing coal-fired power plants by cofiring switchgrass, a biomass energy crop, and coal. This paper presents national level results of applying the methodology to the entire portion of the United States in which switchgrass could be grown without irrigation. We present incremental switchgrass and coal cofiring carbon cost of mitigation curves along with a presentation of regionally specific cofiring economics and policy issues. The results show that cofiring 189 million dry short tons of switchgrass with coal in the existing U.S. coal-fired electricity generation fleet can mitigate approximately 256 million short tons of carbon-dioxide (CO2) per year, representing a 9% reduction of 2005 electricity sector CO2 emissions. Total marginal costs, including capital, labor, feedstock, and transportation, range from $20 to $86/ton CO2 mitigated,with average costs ranging from $20 to $45/ton. If some existing power plants upgrade to boilers designed for combusting switchgrass, an additional 54 million tons of switchgrass can be cofired. In this case, total marginal costs range from $26 to $100/ton CO2 mitigated, with average costs ranging from $20 to $60/ton. Costs for states east of the Mississippi River are largely unaffected by boiler replacement; Atlantic seaboard states represent the lowest cofiring cost of carbon mitigation. The central plains states west of the Mississippi River are most affected by the boiler replacement option and, in general, go from one of the lowest cofiring cost of carbon mitigation regions to the highest. We explain the variation in transportation expenses and highlight regional cost of mitigation variations as transportation overwhelms other cofiring costs.


Assuntos
Carbono , Carvão Mineral , Poaceae , Centrais Elétricas , Modelos Teóricos
14.
Environ Sci Technol ; 41(19): 6657-62, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17969677

RESUMO

This paper presents a linear programming (LP) methodology for estimating the cost of reducing a state's coal-fired power plant carbon dioxide emissions by cofiring switchgrass and coal. LP modeling allows interplay between regionally specific switchgrass production forecasts, coal plant locations, and individual coal plant historic performance data to determine an allocation of switchgrass minimizing cost or maximizing carbon reduction. The LP methodology is applied to two states, Pennsylvania (PA) and Iowa (IA), and results are presented with a discussion of modeling assumptions, techniques, and carbon mitigation policy implications. The LP methodology estimates that, in PA, 4.9 million tons of CO2/year could be mitigated at an average cost of less than $34/ton of CO2 and that, in IA, 7 million tons of CO2/year could be mitigated at an average Cost of Mitigation of $27/ton of CO2. Because the factors determining the cofiring costs vary so much between the two states, results suggest that cofiring costs will also vary considerably between different U.S. regions. A national level analysis could suggest a lowest-cost cofiring region. This paper presents techniques and assumptions that can simplify biomass energy policy analysis with little effect on analysis conclusions.


Assuntos
Poluição do Ar/prevenção & controle , Dióxido de Carbono/economia , Carvão Mineral/economia , Fontes Geradoras de Energia , Panicum/economia , Centrais Elétricas/economia , Poluentes Atmosféricos/economia , Poluição do Ar/economia , Custos e Análise de Custo , Iowa , Modelos Econômicos , Pennsylvania
15.
J Heart Lung Transplant ; 26(2): 108-13, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17258142

RESUMO

BACKGROUND: Renal insufficiency (RI) is a known complication in heart transplant recipients. We sought to determine the prevalence and risk factors for RI in pediatric heart transplant recipients over a long-term follow-up period. METHODS: The study cohort included 77 pediatric heart transplant recipients (35 girls, 18 African Americans) who had a minimum follow-up of 1 year. Data were obtained from pre-transplant evaluations and at 1, 6 and 12 months post-transplant and annually thereafter. Factors evaluated for their influence on renal function included duration of listing, age at transplant, gender, race, cardiac diagnosis, use of assist devices, inotropic support, rejection episodes and use of calcineurin inhibitors. RESULTS: The median age at transplant was 2 years, with a median follow-up duration of 5.1 years. RI was prevalent in 33% pre-transplant, and in 17%, 21% and 25.9% at 1, 3 and 5 years post-transplant, respectively. Two patients developed end-stage renal disease requiring long-term dialysis, with 1 eventually receiving a renal transplant. Significant risk factors for RI were African-American race (p = 0.04), younger age at transplant (p = 0.007), duration of listing (p < 0.0001) and calcineurin inhibitor level (p = 0.003). RI at 6 months post-transplant predicted chronic kidney disease at 5 years (odds ratio = 9). CONCLUSIONS: The prevalence of RI increased during a median follow-up of 5 years in this pediatric heart transplant cohort. African-American race, younger age at transplant, longer duration of listing, high level of calcineurin inhibitors and RI at 6 months were important determinants of RI. These patients should be followed-up carefully with early referral to a pediatric nephrologist if they develop chronic kidney disease.


Assuntos
Transplante de Coração/efeitos adversos , Insuficiência Renal/epidemiologia , Insuficiência Renal/etiologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
16.
Ann Thorac Surg ; 83(2): 680-2, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17258015

RESUMO

Severe tricuspid regurgitation resulting from a flail leaflet is a rare cause of neonatal cyanosis. We report two neonates with profound cyanosis and severe tricuspid regurgitation caused by rupture of the papillary muscle supporting the anterior leaflet, without other structural heart defects. Ductal patency could not be established. Repair of the tricuspid valve was performed by reimplantation of the ruptured papillary muscle head, after initial stabilization using extracorporeal membrane oxygenation. Early recognition and treatment of this otherwise fatal condition can be lifesaving.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cianose/etiologia , Ruptura Cardíaca/complicações , Ruptura Cardíaca/cirurgia , Músculos Papilares , Insuficiência da Valva Tricúspide/complicações , Ecocardiografia , Oxigenação por Membrana Extracorpórea , Ruptura Cardíaca/diagnóstico por imagem , Humanos , Recém-Nascido , Masculino , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/cirurgia , Reimplante , Índice de Gravidade de Doença , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/fisiopatologia , Insuficiência da Valva Tricúspide/cirurgia
17.
Pediatr Cardiol ; 28(1): 34-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17219027

RESUMO

We evaluated the relationship between regional cerebral oxygen saturation (rSO(2)) measured by near-infrared spectroscopy (NIRS) cerebral oximeter with superior vena cava (SVC), inferior vena cava (IVC), right atrium (RA), and pulmonary artery (PA) saturation measured on room air and 100% inspired oxygen administered via a non-rebreather mask (NRB) in children. Twenty nine pediatric post-orthotopic heart transplant patients undergoing an annual myocardial biopsy were studied. We found a statistically significant correlation between rSO(2) and SVC saturations at room air and 100% inspired oxygen concentration via NRB (r = 0.67, p = 0.0002 on room air; r = 0.44, p = 0.02 on NRB), RA saturation (r = 0.56, p = 0.002; r = 0.56, p = 0.002), and PA saturation (r = 0.67, p < 0.001; r = 0.4, p = 0.03). A significant correlation also existed between rSO(2) and measured cardiac index (r = 0.45, p = 0.01) and hemoglobin levels (r = 0.41, p = 0.02). The concordance correlations were fair to moderate. Bias and precision of rSO(2) compared to PA saturations on room air were -0.8 and 13.9%, and they were 2.1 and 15.6% on NRB. A stepwise linear regression analysis showed that rSO(2) saturations were the best predictor of PA saturations on both room air (p = 0.0001) and NRB (p = 0.012). In children with biventricular anatomy, rSO(2) readings do correlate with mixed venous saturation.


Assuntos
Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Oximetria , Consumo de Oxigênio , Adolescente , Fatores Etários , Cateterismo Cardíaco , Criança , Pré-Escolar , Feminino , Transplante de Coração , Humanos , Lactente , Masculino , Período Pós-Operatório , Espectroscopia de Luz Próxima ao Infravermelho , Fatores de Tempo
18.
Environ Sci Technol ; 40(9): 2877-86, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16719086

RESUMO

Discussions of alternative fuel and propulsion technologies for transportation often overlook the infrastructure required to make these options practical and cost-effective. We estimate ethanol production facility locations and use a linear optimization model to consider the economic costs of distributing various ethanol fuel blends to all metropolitan areas in the United States. Fuel options include corn-based E5 (5% ethanol, 95% gasoline) to E16 from corn and switchgrass, as short-term substitutes for petroleum-based fuel. Our estimates of 1-2 cents per L of ethanol blend for downstream rail or truck transportation remain a relatively small fraction of total fuel cost. However, for even the relatively small blends of ethanol modeled, the transportation infrastructure demands would be comparably larger than the current demands of petroleum. Thus if ethanol is to be competitive in the long run, then in addition to process efficiency improvements, more efficient transportation infrastructure will need to be developed, such as pipelines. In addition to these results, national and regional policy challenges on how to pay for and optimize a new fuel and distribution infrastructure in the United States are discussed.


Assuntos
Celulose/química , Etanol/química , Biomassa , Fontes Geradoras de Energia , Meio Ambiente , Gasolina , Veículos Automotores , Poaceae , Política Pública , Meios de Transporte , Estados Unidos , Emissões de Veículos
19.
Congenit Heart Dis ; 1(3): 54-62, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-18377548

RESUMO

The Pediatric Heart Transplant Study (PHTS) group was founded in 1991 as a voluntary, collaborative effort dedicated to the advancement of the science and treatment of children following listing for heart transplantation. Since 1993, the PHTS has collected data in an international, prospective, event-driven database that examines risk factors for outcome events following listing for transplantation. The events include transplantation, death, rejection, infection, malignancy, graft vasculopathy, and retransplantation. Over its 12 years of existence, the PHTS has made major contributions to the field of pediatric heart transplantation, especially in the areas of outcome analysis and risk factor assessment for death and other major morbidities after listing and after transplantation. The new challenges facing the PHTS include how to implement the practice of evidence-based medicine in the field of pediatric heart transplantation and how to support ongoing data collection and analysis to provide long-term outcomes as the PHTS subjects enter their second decade after transplantation.


Assuntos
Bases de Dados Factuais , Transplante de Coração/estatística & dados numéricos , Sistema de Registros , Adolescente , Criança , Pré-Escolar , Rejeição de Enxerto , Cardiopatias Congênitas/cirurgia , Transplante de Coração/mortalidade , Humanos , Lactente , Recém-Nascido , Internacionalidade , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Medição de Risco , Taxa de Sobrevida
20.
Pediatrics ; 118(4): e1250-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17015513

RESUMO

A member of the Tennessee state legislature recently proposed a bill that would mandate all newborn infants to undergo pulse oximetry screening for the purpose of identifying those with critical structural heart disease before discharge home. The Tennessee Task Force on Screening Newborn Infants for Critical Congenital Heart Defects was convened on September 29, 2005. This group reviewed the current medical literature on this topic, as well as data obtained from the Tennessee Department of Health, and debated the merits and potential detriments of a statewide screening program. The estimated incidence of critical congenital heart disease is 170 in 100,000 live births, and of those, 60 in 100,000 infants have ductal-dependent left-sided obstructive lesions with the potential of presentation by shock or death if the diagnosis is missed. Of the latter group, the diagnosis is missed in approximately 9 in 100,000 by fetal ultrasound assessment and discharge examination and might be identified by a screening program. Identification of the missed diagnosis in these infants before discharge could spare many of them death or neurologic sequelae. Four major studies using pulse oximetry screening were analyzed, and when data were restricted to critical left-sided obstructive lesions, sensitivity values of 0% to 50% and false-positive rates of between 0.01% and 12% were found in asymptomatic populations. Because of this variability and other considerations, a meaningful cost/benefit analysis could not be performed. It was the consensus of the task force to provide a recommendation to the legislature that mandatory screening not be implemented at this time. In addition, we determined that a very large, prospective, perhaps multistate study is needed to define the sensitivity and false-positive rates of lower-limb pulse oximetry screening in the asymptomatic newborn population and that there needs to be continued partnering between the medical community, parents, and local, state, and national governments in decisions regarding mandated medical care.


Assuntos
Diretrizes para o Planejamento em Saúde , Cardiopatias Congênitas/diagnóstico , Triagem Neonatal/legislação & jurisprudência , Triagem Neonatal/estatística & dados numéricos , Oximetria/estatística & dados numéricos , Comitês Consultivos , Reações Falso-Positivas , Política de Saúde , Cardiopatias Congênitas/epidemiologia , Humanos , Incidência , Recém-Nascido , Formulação de Políticas , Sensibilidade e Especificidade , Tennessee/epidemiologia
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