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1.
J Vasc Surg Cases Innov Tech ; 10(1): 101380, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38226318

RESUMO

Chronic radiation-induced arterial injury is generally predictable by known tumor types and anatomic location. We present the first case of radiation-induced chronic aortic occlusion associated with a small pelvis secondary to the treatment of childhood Ewing sarcoma. The patient presented with profound claudication and accelerated atherosclerosis obliterans of the aortoiliac system and failed endovascular treatment. Successful aortic reconstruction was performed. This case highlights the long-term effects of chemoradiation to the aortoiliac segment and pelvic bones in a child, and the technical challenges of vascular reconstruction in an underdeveloped irradiated pelvis.

2.
J Vasc Surg Cases Innov Tech ; 9(4): 101349, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38106349

RESUMO

Few descriptions of using the femoral vein as an arterial replacement exist in the pediatric surgical literature. A 3-year-old child sustained a gunshot wound to the right subclavian artery, which resulted in ischemia to the upper extremity. The left femoral vein was harvested and used to reconstruct the subclavian artery. This report highlights a rare case of subclavian artery reconstruction using a femoral vein conduit in a young child after a penetrating injury.

3.
J Surg Res ; 228: 271-280, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29907222

RESUMO

BACKGROUND: Addition of en bloc segmental venous reconstruction (VR) to pancreaticoduodenectomy (PD) for venous involvement of pancreatic tumors increases the complexity of the operation and may increase complications. The long-term mesenteric venous patency rate and oncologic outcome has not been well defined. METHODS: Our prospective database was reviewed to assess 90-day postoperative outcomes for patients who underwent PD or PD + VR (September 2004-June 2016). Two independent observers reviewed CT scans to determine long-term vein patency. In patients with pancreatic ductal adenocarcinoma, the impact of VR on 5-year overall survival was assessed using multivariate Cox proportional hazards regression. Student's t-test was used to evaluate continuous variables and the chi-square test for categorical variables. RESULTS: Three hundred ninety-three patients underwent PD (51 PD + VR). Patients undergoing PD + VR had longer operations (561 ± 119 versus 433 ± 89 min, P < 0.00001) and greater blood loss (768 ± 812 versus 327 ± 423 cc, P < 0.00001). There was no difference in 90-day mortality, overall postoperative complication rates, complication severity grades, reoperation, readmission, or length of stay. 26.7% experienced venous thrombosis. Most thromboses occurred in the first year after surgery, but we also observed late thrombosis in 1 patient after 89-month follow-up. Among 135 patients with pancreatic ductal adenocarcinoma, survival was significantly longer in the PD-alone group (31.3 months [95% confidence interval: 22.9-40.0] versus 17.0 [95% confidence interval: 13.0-19.1], plog-rank = 0.013). CONCLUSIONS: PD + VR does not increase short-term morbidity, but venous thrombosis is frequent and can occur long after surgery. Survival is inferior when VR is required especially in the absence of neoadjuvant chemotherapy.


Assuntos
Carcinoma Ductal Pancreático/cirurgia , Veias Mesentéricas/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Procedimentos de Cirurgia Plástica/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Trombose Venosa/epidemiologia , Idoso , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Carcinoma Ductal Pancreático/mortalidade , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Pancreaticoduodenectomia/métodos , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/métodos , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Grau de Desobstrução Vascular , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
5.
J Vasc Surg ; 66(4): 1175-1183.e1, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28756045

RESUMO

BACKGROUND: Endovascular therapy has been increasingly used for critically injured adults. However, little is known about the epidemiology and outcomes of endovascularly managed arterial injuries in children. We therefore aimed to evaluate recent trends in the endovascular management of pediatric arterial injuries and its association with early survival. METHODS: An 8-year analysis of the National Trauma Databank (2007-2014) was performed to extract all pediatric trauma patients (aged ≤16 years) with arterial injuries. Demographics, clinical data, interventions (endovascular vs open), and outcomes (in-hospital mortality and length of stay) were extracted. Patients undergoing endovascular or open procedures were compared for differences in clinical characteristics using bivariate analysis. Multivariable logistic regression analysis quantified the association between endovascular therapy and survival in the context of other variables predictive of survival on univariate analysis, with α ≤ .05. RESULTS: There were 35,771 pediatric patients available for analysis. Overall, there was a significant increase in the use of endovascular procedures (from 7.8% in 2007 to 12.9% in 2014; P < .001), particularly among blunt trauma patients (5.8% in 2007 to 15.7% in 2014; P < .001). Conversely, a significant decrease was noted for open procedures (P < .001). There was a stepwise increase in the proportion of patients managed endovascularly as the Injury Severity Score (ISS) increased (highest in the ISS spectrum of 31-50). Angioembolization of internal iliac injury and thoracic aortic endograft placement were the two most common endovascular procedures (n = 88 [33.4%] and n = 60 [22.9%], respectively). There were 331 decedents (9.1% vascular injured children), 242 (73.1%) of whom were dead on arrival. After controlling for differences in demographics and clinical data, when outcomes were compared between patients who underwent endovascular and open procedures, there were no significant differences regarding in-hospital mortality (3.0% vs 3.6%; odds ratio, 0.7; 95% confidence interval, 0.1-6.1; P = .778). A logistic regression model identified Glasgow Coma Scale score ≤8, ISS ≥16, positive result of ethanol or drug screen, and systolic blood pressure <90 mm Hg on admission as independent risk factors for death. CONCLUSIONS: The use of endovascular therapy in pediatric vascular arterial trauma has significantly increased, especially among severely injured blunt trauma patients. Despite this successful integration into care, there was no in-hospital survival advantage conferred by endovascular therapy compared with traditional open therapy. Approximately 10% of children with arterial injuries died during initial trauma assessment before therapy could be offered. Glasgow Coma Scale score ≤8, ISS ≥16, positive result of ethanol or drug screen, and systolic blood pressure <90 mm Hg on admission were identified as independent risk factors for death. As children are a population of vulnerable patients, long-term, multicenter studies are required to determine the most appropriate use of and indications for endovascular therapy in pediatric arterial trauma.


Assuntos
Artérias/lesões , Procedimentos Endovasculares/tendências , Padrões de Prática Médica/tendências , Lesões do Sistema Vascular/terapia , Adolescente , Fatores Etários , Amputação Cirúrgica/tendências , Implante de Prótese Vascular/tendências , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Bases de Dados Factuais , Embolização Terapêutica/tendências , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Escala de Coma de Glasgow , Mortalidade Hospitalar , Humanos , Lactente , Escala de Gravidade do Ferimento , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Lesões do Sistema Vascular/diagnóstico , Lesões do Sistema Vascular/mortalidade
6.
J Vasc Surg ; 59(6): 1488-94, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24709440

RESUMO

OBJECTIVE: The objective of this study was to review our 27-year clinical experience with open proximal abdominal aortic aneurysm repairs, with a focus on long-term survival. METHODS: A retrospective cohort study was undertaken of all patients who underwent proximal abdominal aortic aneurysm repair between 1986 and 2013 at a tertiary care referral center. Demographics, operative variables, complications, and 30-day mortality were analyzed. Postoperative acute kidney injury was analyzed by the RIFLE (Risk, Injury, Failure, Loss, End-stage renal disease)/Acute Kidney Injury Network criteria. Long-term survival was assessed through review of electronic medical records and the Social Security Death Index. Associations between demographics and complications were investigated to determine predictors of long-term survival. RESULTS: The study identified 245 patients. Mean age was 71 years (range, 38-92 years); 69% were men, and 88% were white. Aneurysm type was juxtarenal in 127 patients (52%), suprarenal in 68 patients (28%), and type IV thoracoabdominal in 50 patients (20%). In-hospital mortality was 3.3% (eight patients), and 30-day mortality was 2.9% (seven patients). At least one major complication occurred in 64% of the patients, which included the following: acute kidney injury, 60% (persistent acute kidney injury at discharge, however, was 28%, and hemodialysis at discharge was 1.6%); major pulmonary complications, 22%; myocardial infarction, 4%; visceral ischemia, 2%; and paraplegia, 0.5%. Median follow-up was 54 months. Kaplan-Meier survival estimates were 70% at 5 years and 43% at 10 years. Variables associated with poorer survival included congestive heart failure (hazard ratio [HR], 3.5; P < .001), chronic obstructive pulmonary disease (HR, 1.8; P < .002), and increased aneurysm size at presentation (HR, 1.1; P < .013). Persistent stage 3 acute kidney injury was associated with poor long-term survival. CONCLUSIONS: Open surgical repair of proximal abdominal aortic aneurysms can be performed with low mortality. Acute kidney injury is the most frequent complication, but the need for hemodialysis at discharge is low. Long-term survival is favorable. These data should assist in establishing benchmarks for endovascular repair of complex proximal abdominal aortic aneurysms.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Complicações Pós-Operatórias/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Estimativa de Kaplan-Meier , Masculino , Michigan/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento
7.
Ann Vasc Surg ; 28(7): 1791.e5-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24667284

RESUMO

Common femoral vein traumatic injuries are rare. Surgical management is controversial and by nature case specific. In this report, we present an unusual case of an isolated common femoral vein injury from a gunshot blast repaired with an interposition internal jugular vein bypass. To our knowledge, this is the first reported case of an isolated common femoral vein reconstructed in this manner.


Assuntos
Traumatismos por Explosões/cirurgia , Veia Femoral/lesões , Veia Femoral/cirurgia , Veias Jugulares/transplante , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Ferimentos por Arma de Fogo/cirurgia , Adolescente , Humanos , Masculino
8.
J Vasc Surg ; 54(4): 1157-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21723686

RESUMO

Infection of an endovascular abdominal aneurysm repair (EVAR) is rare but has become more prevalent with the standardization of EVAR for treating infrarenal abdominal aortic aneurysms. The understanding of this complex aortic condition has improved but still remains to evolve. We present a patient with an EVAR infection manifesting with juxtarenal aortic rupture as a result of a urinary tract infection. This report describes an unusual presentation of an EVAR infection treated with in situ aortic reconstruction and provides >1 year of follow-up.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Prótese Vascular/efeitos adversos , Remoção de Dispositivo , Procedimentos Endovasculares/efeitos adversos , Infecções Relacionadas à Prótese/cirurgia , Antibacterianos/uso terapêutico , Ruptura Aórtica/diagnóstico por imagem , Ruptura Aórtica/microbiologia , Aortografia/métodos , Implante de Prótese Vascular/instrumentação , Desbridamento , Procedimentos Endovasculares/instrumentação , Escherichia coli/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Omento/cirurgia , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/microbiologia , Reoperação , Retalhos Cirúrgicos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Infecções Urinárias/microbiologia
9.
J Vasc Surg ; 54(2): 515-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21316902

RESUMO

Abdominal aortic injury as a result of blunt trauma is a rare event and has been described in few children. A 6-year-old girl presented with acute bilateral lower extremity ischemia, and a triad of acute aortic occlusion, intra-abdominal visceral injury, and a lumbar chance fracture after sustaining a seat belt injury from a motor vehicle collision. An emergency aortic thromboendarterectomy and primary repair were performed. This represents one of the few reports of acute traumatic aortic thrombosis in a child and highlights the surgical treatment of acute abdominal aortic injury in a pediatric patient.


Assuntos
Acidentes de Trânsito , Aorta Abdominal/cirurgia , Doenças da Aorta/cirurgia , Arteriopatias Oclusivas/cirurgia , Endarterectomia , Cintos de Segurança/efeitos adversos , Trombose/cirurgia , Lesões do Sistema Vascular/cirurgia , Doença Aguda , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/lesões , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etiologia , Aortografia/métodos , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/etiologia , Criança , Feminino , Humanos , Isquemia/etiologia , Extremidade Inferior/irrigação sanguínea , Vértebras Lombares/lesões , Fraturas da Coluna Vertebral/etiologia , Trombose/diagnóstico por imagem , Trombose/etiologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia
11.
J Vasc Surg ; 52(5): 1164-72, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20732782

RESUMO

OBJECTIVE: To examine and report surgical results from a contemporary experience of open abdominal aortic reconstruction in patients with chronic atherosclerotic abdominal aortic occlusion (CAAAO). METHODS: Between January 1999 through May 2010, 54 patients with CAAAO were identified and retrospectively reviewed. CAAAOs were categorized into infrarenal aortic occlusions (IRAOs) and juxtarenal aortic occlusions (JRAOs) based on superior extension of thrombus and requirement for supra-renal aortic clamping to repair. Morbidity, mortality, hospital stay, and operative variables were assessed. The χ2 or Fisher test and the Wilcoxon rank sum test were used to compare demographic and operative variables between two aortic occlusion groups (IRAO and JRAO). Univariate and multivariate analyses were performed to assess factors associated with surgical outcomes and hospital stay. The Kaplan-Meier method was used to calculate survival and patency rates. RESULTS: Fifty patients underwent aortic reconstructions with aorto-bifemoral or iliac bypass, and three underwent a remote axillo-femoral bypass procedure. There were 35 (64.8%) males, and 19 (35.2%) females. Median age was 51.9 years (range, 32-72 years). Of the two CAAAO groups, there were 20 IRAOs and 33 JRAOs. Aorto-renal thromboendartectomy was performed in 26 (49.1%) patients; 26 (75.8%) among JRAOs versus 1 (5%) of IRAOs (P<.01). Proximal aortic clamps were required in 28 (85%) of JRAOs and 3 (15%) of IRAOs (P<.01). Thirty-day and in-hospital mortality was zero. Median length of hospital stay was 7 days (range, 4 to 66 days), and median intensive care unit length of stay was 3 days (range, 1-22 days). Complications included cardiopulmonary dysfunction in four (8%), postoperative renal insufficiency in 10 (18.9%), and other postoperative complications in 15 (28.3%). All 10 with renal insufficiency recovered renal function to baseline creatinine or a creatinine value<1.1 mg/dL. Mean increases in right and left ankle-brachial indicess were 0.54±0.25 and 0.59±0.22, respectively. On univariate analysis, coronary artery disease and African American race were predictors of postoperative complications (P=.048). Age was significantly associated with total complications. Patients with postoperative complications and/or renal insufficiency were older than those without such complications (P=.02) Independent predictors of prolonged hospital stay were intraoperative blood replacement (P=.003), postoperative complications (P<.01), and postoperative renal insufficiency (P<.01). Prolonged intensive care unit stay was predicted by JRAO (P=.04), postoperative complications (P=.02), and postoperative renal insufficiency (P=.013). Survival at 3, 5, and 7 years were 86.6%, 76.5% and 50.9%, respectively. The reduced survival rates were predicted by previous myocardial infarction and existing coronary artery disease (P<.01). CONCLUSION: Abdominal aortic reconstruction is a safe method for treating CAAAO with low associated morbidity and mortality. Aorto-renal thromboendartectomy with supra-renal aortic clamping and aortic replacement remains an effective treatment for those with significant pararenal aortic disease, and can be performed without significant renal impairment.


Assuntos
Aorta Abdominal/cirurgia , Doenças da Aorta/cirurgia , Aterosclerose/cirurgia , Implante de Prótese Vascular , Adulto , Idoso , Aorta Abdominal/fisiopatologia , Doenças da Aorta/mortalidade , Doenças da Aorta/fisiopatologia , Aterosclerose/mortalidade , Aterosclerose/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Distribuição de Qui-Quadrado , Doença Crônica , Constrição , Constrição Patológica , Endarterectomia , Feminino , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Modelos Lineares , Modelos Logísticos , Louisiana , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Trombectomia , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
12.
Ann Vasc Surg ; 24(7): 950.e3-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20599345

RESUMO

Inflammatory aortic aneurysms are unusual vascular lesions and most commonly involve the infrarenal segment of the abdominal aorta. These complex aneurysms represent a challenge to the vascular surgeon and become even more difficult as the extent of the aneurysm and size of the inflammatory mass increase. Although well described, few cases of giant inflammatory aneurysms are reported. In this case, we review the clinical presentation and surgical management of a patient with a giant pararenal abdominal aortic aneurysm and highlight an uncommon morphologic pattern of aortic disease and provide a review of relevant literature.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aortite/cirurgia , Implante de Prótese Vascular , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortite/diagnóstico por imagem , Aortografia/métodos , Humanos , Masculino , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
J Vasc Surg ; 51(4): 1003-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20080008

RESUMO

Nonatherosclerotic etiologies of arterial insufficiency are uncommon but important causes of chronic lower extremity ischemia. We report a patient with multiple hereditary exostoses (MHE) presenting with lifestyle-limiting lower extremity claudication and popliteal artery occlusion secondary to a large osteochondroma. The presence of MHE with associated osteochondroma resulting in arterial occlusion is a rare condition. Management strategies for treating large osteochondromas adjacent to or with vessel involvement in asymptomatic patients remain undefined.


Assuntos
Arteriopatias Oclusivas/genética , Exostose Múltipla Hereditária/genética , Claudicação Intermitente/genética , Isquemia/genética , Extremidade Inferior/irrigação sanguínea , Artéria Poplítea , Tíbia/patologia , Angiografia Digital , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/cirurgia , Constrição Patológica , Exostose Múltipla Hereditária/complicações , Exostose Múltipla Hereditária/patologia , Feminino , Humanos , Claudicação Intermitente/diagnóstico , Claudicação Intermitente/cirurgia , Isquemia/diagnóstico , Isquemia/cirurgia , Pessoa de Meia-Idade , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Veia Safena/transplante , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Procedimentos Cirúrgicos Vasculares
14.
J Vasc Surg ; 43(5): 921-7; discussion 927-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16678684

RESUMO

PURPOSE: Few large series document surgical outcomes for patients with pararenal abdominal aortic aneurysms (PAAAs), defined as aneurysms including the juxtarenal aorta or renal artery origins that require suprarenal aortic clamping. No standard endovascular alternatives presently exist; however, future endovascular branch graft repairs ultimately must be compared with the gold standard of open repair. To this end, we present a 10-year experience. METHODS: Between 1993 and 2003, 3058 AAAs were repaired. Perioperative variables, morbidity, and mortality were retrospectively assessed. Renal insufficiency was defined as a rise in the concentration of serum creatinine by > or = 0.5 mg/dL. Factors predicting complications were identified by multivariate analyses. Morbidity and 30-day mortality were evaluated with multiple logistic regression analysis. RESULTS: Of a total of 3058 AAA repairs performed, 247 were PAAAs (8%). Mean renal ischemia time was 23 minutes (range, 5 to 60 minutes). Cardiac complications occurred in 32 patients (13%), pulmonary complications in 38 (16%), and renal insufficiency in 54 (22%). Multivariate analysis associated myocardial infarction with advanced age (P = .01) and abnormal preoperative serum creatinine (>1.5 mg/dL) (P = .08). Pulmonary complications were associated with advanced age (P = .03), renal artery bypass (P = .02), increased mesenteric ischemic time (P = .01), suprarenal aneurysm repair (P < .0008), and left renal vein division (P = .01). Renal insufficiency was associated with increased mesenteric ischemic time (P = .001), supravisceral clamping (P = .04), left renal vein division (P = .04), and renal artery bypass (P = .0002), but not renal artery reimplantation or endarterectomy. New dialysis was required in 3.7% (9/242). Abnormal preoperative serum creatinine (>1.5 mg/dL) was predictive of the need for postoperative dialysis (10% vs 2%; P = .04). Patients with normal preoperative renal function had improved recovery (93% vs 36%; P = .0002). The 30-day surgical mortality was 2.5% (6/247) but was not predicted by any factors, and in-hospital mortality was 2.8% (7/247). Median intensive care and hospital stays were 3 and 9 days, respectively, and longer stays were associated with age at surgery (P = .007 and P = .0002, respectively) and any postoperative complication. CONCLUSIONS: PAAA repair can be performed with low mortality. Renal insufficiency is the most frequent complication, but avoiding renal artery bypass, prolonged mesenteric ischemia time, or left renal vein transection may improve results.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Isquemia/etiologia , Falência Renal Crônica/etiologia , Rim/irrigação sanguínea , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/mortalidade , Causas de Morte , Comorbidade , Feminino , Humanos , Isquemia/mortalidade , Falência Renal Crônica/mortalidade , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Medição de Risco/estatística & dados numéricos , Taxa de Sobrevida
16.
Proc Natl Acad Sci U S A ; 100(12): 7231-4, 2003 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-12782790

RESUMO

The migration of lymphocytes into inflammatory tissue requires the migrating cell to overcome mechanical forces produced by blood flow. A generally accepted hypothesis is that these forces are overcome by a multistep sequence of adhesive interactions between lymphocytes and endothelial cells. This hypothesis has been recently challenged by results demonstrating wall shear stress on the order of 20 dyn/cm(2) in vivo and infrequent lymphocyte-endothelial adhesion at wall shear stress >1-2 dyn/cm(2) in vitro. Here, we show that lymphocyte slowing and transmigration in the skin is associated with microangiectasias, i.e., focal structural dilatations of microvessel segments. Microangiectasias are inducible within 4 days of the onset of inflammation and lead to a greater than 10-fold local reduction in wall shear stress. These findings support the hypothesis that a preparatory step to lymphocyte transmigration involves structural adaptations in the inflammatory microcirculation.


Assuntos
Movimento Celular/fisiologia , Inflamação/patologia , Linfócitos/patologia , Linfócitos/fisiologia , Animais , Fenômenos Biomecânicos , Adesão Celular , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Hemodinâmica , Técnicas In Vitro , Inflamação/sangue , Microcirculação/patologia , Microcirculação/fisiopatologia , Microscopia Eletrônica de Varredura , Microscopia de Vídeo , Ovinos
17.
J Cell Physiol ; 194(1): 54-62, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12447989

RESUMO

The cellular immune response depends on the delivery of lymphocytes from the lymph node to the peripheral site of antigenic challenge. During their passage through the inflammatory microcirculaton, the migratory cells can become transiently immobilized or "trapped" in small caliber vessels. In this report, we used intravital microscopy and temporal area mapping to define the dynamic deformation of efferent lymph-derived mononuclear cells trapped in the systemic inflammatory microcirculation. Mononuclear cells obtained from the efferent lymph draining the oxazolone-stimulated microcirculation were labeled with fluorescent dye and reinjected into the feeding arterial circulation. Intravital video microscopy observed thousands of cells passing through the microcirculation; 35 cells were "trapped" in the oxazolone-stimulated microcirculation. Temporal area maps of the trapped cells demonstrated dramatic slowing and deformation. The cells were trapped in the microcirculation for a median of 8.90 sec (range 5-17 sec) prior to returning to the flow stream. During this period, the cells showed sustained movement associated with both antegrade locomotion (mean cell velocity = 7.92 microm/sec; range 1.16-14.23 microm/sec) and dynamic elongation (median cell length = 73.8 microm; range 58-144 microm). In contrast, efferent lymph-derived cells passing unimpeded through the microcirculation demonstrated rapid velocity (median velocity = 216 microm/sec) and spherical geometry (median diameter = 14.6 microm). Further, the membrane surface area of the "trapped" cells, calculated based on digital image morphometry and corrosion cast scanning electron microscopy, suggested that the fractional excess membrane of the cells in the efferent lymph was significantly greater than previous estimates of membrane excess. These data indicate that transient immobilization of efferent lymph-derived mononuclear cells in the systemic inflammatory microcirculation is rare. When "trapping" does occur, the shape changes and sustained cell movement facilitated by excess cell membrane may contribute to the return of the "trapped cells" into the flow stream.


Assuntos
Quimiotaxia de Leucócito/imunologia , Inflamação/imunologia , Linfócitos/imunologia , Microcirculação/imunologia , Monócitos/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Membrana Celular/imunologia , Membrana Celular/ultraestrutura , Tamanho Celular/imunologia , Imunofluorescência , Linfonodos/imunologia , Linfócitos/ultraestrutura , Microcirculação/ultraestrutura , Microscopia Eletrônica de Varredura , Monócitos/ultraestrutura , Oxazolona/farmacologia , Ovinos
18.
J Appl Physiol (1985) ; 93(3): 966-73, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12183492

RESUMO

The application of the epicutaneous antigen oxazolone results in persistent induration and erythema; however, the relative changes in lymph and blood flow in the inflammatory skin are largely unknown. To define the contribution of lymph and blood flow to the clinical appearance of cutaneous inflammation, we studied the sheep ear after the application of oxazolone. As a model for the study of these changes, the sheep ear had several experimental advantages: 1) a simplified superficial vascular network, 2) defined lymphatic drainage, and 3) an avascular and alymphatic cartilaginous barrier. Lymph flow was continuously monitored by cannulation of the prescapular efferent lymph duct. Blood flow, as reflected by cutaneous erythema, was noninvasively measured by use of a visible-spectrum spectrophotometer. The application of the epicutaneous oxazolone resulted in increased ear thickness for >7 days. The lymph flow from the oxazolone-stimulated ear peaked between 24 and 48 h after oxazolone stimulation. Spectrophotometric evaluation indicated that the cutaneous erythema peaked 72-96 h after application of oxazolone. Corrosion casting and scanning electron microscopy of the microcirculation at 96 h after antigen stimulation demonstrated significant dilatation of the superficial vascular network. These results suggest a biphasic response to oxazolone stimulation: 1) an early increase in vascular permeability associated with increased lymph flow and 2) a subsequent increase in relative blood flow associated with a dilated inflammatory microcirculation.


Assuntos
Adjuvantes Imunológicos/farmacologia , Circulação Sanguínea/efeitos dos fármacos , Toxidermias/patologia , Toxidermias/fisiopatologia , Linfa/efeitos dos fármacos , Linfa/metabolismo , Oxazolona/farmacologia , Animais , Toxidermias/metabolismo , Orelha , Masculino , Ovinos , Pele/efeitos dos fármacos , Pele/patologia
19.
Dev Comp Immunol ; 26(1): 111-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11687269

RESUMO

The lymph node is a specialized microenvironment for the regulation of immune responses. The reticular network of the lymph node provides a structure that facilitates not only intercellular interactions, but the intranodal flow of lymph fluid. To assess biochemical changes in the nodal lymph plasma after antigen stimulation, prescapular lymph nodes in sheep were stimulated with the epicutaneous antigen oxazolone. The efferent lymph from both antigen-stimulated and contralateral control prescapular lymph nodes was continuously monitored for more than 120 h. The oxazolone-stimulated lymph plasma was associated with a selective increase in cholesterol content during the 'recruitment' phase of lymph node enlargement. The peak in cholesterol was followed closely by a significant increase in lymph plasma LDH concentration. In contrast, there was no significant difference between oxazolone-stimulated and control lymph plasma in the concentration of triglycerides, albumin, alkaline phosphatase, and alanine transferase. These selective biochemical changes in the efferent lymph appeared to reflect the dynamics of lymphocyte activation within the lymph node as well as provide a practical measure of the lymph node response to antigen stimulation.


Assuntos
Sistema Linfático/imunologia , Animais , Colesterol/análise , L-Lactato Desidrogenase/análise , Lipídeos/análise , Linfa/imunologia , Linfonodos/imunologia , Oxazolona/imunologia , Proteínas/análise , Ovinos
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