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1.
Khirurgiia (Mosk) ; (1): 90-92, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33395518

RESUMO

We report a complex reconstruction of arteriovenous fistula (AVF). Proximal stenosis of cephalic vein was followed by aneurysms of fistulous veins (distal segment of cephalic vein and median cubital vein) complicated by AVF thrombosis. Blood outflow from AVF was retrograde. One week after thrombosis, an aneurysm of median cubital vein containing dense clots was excised. We resected cephalic vein wall and repaired the vessel. Anastomosis with the brachial artery was created distal to the last anastomosis. Proximal cephalic vein repair was performed using resected aneurysm walls. After a year, AVF has been successfully used for hemodialysis.


Assuntos
Derivação Arteriovenosa Cirúrgica , Artéria Braquial/cirurgia , Diálise Renal , Doenças Vasculares/cirurgia , Veias/cirurgia , Aneurisma/etiologia , Aneurisma/cirurgia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Artéria Braquial/diagnóstico por imagem , Humanos , Resultado do Tratamento , Doenças Vasculares/etiologia , Grau de Desobstrução Vascular , Procedimentos Cirúrgicos Vasculares/métodos , Insuficiência Venosa/etiologia , Insuficiência Venosa/cirurgia , Trombose Venosa/etiologia , Trombose Venosa/cirurgia
2.
Sci Rep ; 10(1): 16387, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009417

RESUMO

Pattern recognition and automatic decision support methods provide significant advantages in the area of health protection. The aim of this work is to develop a low-cost tool for monitoring arteriovenous fistula (AVF) with the use of phono-angiography method. This article presents a developed and diagnostic device that implements classification algorithms to identify 38 patients with end stage renal disease, chronically hemodialysed using an AVF, at risk of vascular access stenosis. We report on the design, fabrication, and preliminary testing of a prototype device for non-invasive diagnosis which is very important for hemodialysed patients. The system includes three sub-modules: AVF signal acquisition, information processing and classification and a unit for presenting results. This is a non-invasive and inexpensive procedure for evaluating the sound pattern of bruit produced by AVF. With a special kind of head which has a greater sensitivity than conventional stethoscope, a sound signal from fistula was recorded. The proces of signal acquisition was performed by a dedicated software, written specifically for the purpose of our study. From the obtained phono-angiogram, 23 features were isolated for vectors used in a decision-making algorithm, including 6 features based on the waveform of time domain, and 17 features based on the frequency spectrum. Final definition of the feature vector composition was obtained by using several selection methods: the feature-class correlation, forward search, Principal Component Analysis and Joined-Pairs method. The supervised machine learning technique was then applied to develop the best classification model.


Assuntos
Fístula Arteriovenosa/diagnóstico , Algoritmos , Angiografia , Derivação Arteriovenosa Cirúrgica/métodos , Constrição Patológica/diagnóstico , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal/métodos , Diálise Renal/métodos , Processamento de Sinais Assistido por Computador , Estetoscópios
3.
J Bras Nefrol ; 42(2 suppl 1): 41-43, 2020 Aug 26.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32877498

RESUMO

Vascular accesses for hemodialysis are considered the patient's lifeline and their maintenance is essential for treatment continuity. Following the example of institutions in other countries affected by the Covid-19 pandemic, the Brazilian Society of Nephrology developed these guidelines for healthcare services, elaborating on the importance of carrying out procedures for the preparation and preservation of vascular accesses. Creating definitive accesses for hemodialysis, grafts and arteriovenous fistulas are non-elective procedures, as well as the transition from the use of non-tunneled catheters to tunneled catheters, which cause less morbidity. In the case of patients with suspected or confirmed coronavirus infection, one may postpone the procedures for the quarantine period, to avoid spreading the disease.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Diálise Renal/métodos , Dispositivos de Acesso Vascular , Comitês Consultivos , Derivação Arteriovenosa Cirúrgica/normas , Brasil , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Cirúrgicos Eletivos/normas , Emergências , Humanos , Nefrologia/normas , Pandemias , Sociedades Médicas
5.
Ann Vasc Surg ; 67: 448.e1-448.e10, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32209414

RESUMO

BACKGROUND: Brachio-basilic/brachial transposition arteriovenous fistula has emerged as one of the autologous arteriovenous fistula options. However, there have not been many reports on the outcomes of basilic or brachial elevation of arteriovenous fistula compared with those of conventional transposition. We evaluated the efficacy of modified brachio-basilic and brachio-brachial arteriovenous fistula creation with short-segment elevation preserving the axillary area. METHODS: From March 2016 to August 2018, medical records of the patients who underwent short-segment elevation of brachio-basilic or brachio-brachial arteriovenous fistula in the upper arm (sBAE or sBRE) were reviewed retrospectively. RESULTS: Of the 51 patients, 37 underwent sBAE and 14 underwent sBRE. Maturation failure occurred in two patients (3.92%), who underwent sBAE. Stenosis was the most common complication, which developed in 13 patients (25.5%), and there was no significant difference between the sBAE and the sBRE. In the 51 patients, cumulative primary patency rates at 6 and 12 months were 88.3% and 69.1%, respectively. Assisted primary patency rates at 6 and 12 months were 97.8% and 90.7%, respectively. Secondary patency rates at 6 and 12 months were both 100%. There were no significant differences between the sBAE and the sBRE in 1-year primary patency (79.1% vs. 46.7%; P = 0.20), assisted primary patency (91.6% vs. 88.1%; P = 0.36), and secondary patency rates (100% vs. 100%). CONCLUSIONS: Brachio-basilic/brachial arteriovenous fistula with short-segment elevation preserving the axilla showed excellent 1-year patency rate, easier cannulation, and other future advantages, and therefore, is a logical modification of conventional transposition of arteriovenous fistula.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Axila/irrigação sanguínea , Artéria Braquial/cirurgia , Diálise Renal , Extremidade Superior/irrigação sanguínea , Veias/cirurgia , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular , Veias/diagnóstico por imagem , Veias/fisiopatologia
6.
Hemodial Int ; 24(2): E33-E36, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32141217

RESUMO

A young lady with an arteriovenous (AV) fistula on hemodialysis was referred for surgical management following a failed endovascular approach to relieve central venous occlusion. She had an obstructed left brachiocephalic vein with a history of numerous central vein catheter placements. Alternative routes for new arteriovenous fistula creation had been exhausted due to previous contralateral upper limb fistula rupture and ligation. To the best of our knowledge, no similar cases of airway obstruction in central venous occlusion occurring in hemodialysis patients with AV fistula have been reported. The importance of identifying the possible emergency red flags in hemodialysis patients with central venous occlusion is important to prevent unwanted consequences.


Assuntos
Obstrução das Vias Respiratórias/economia , Obstrução das Vias Respiratórias/etiologia , Fístula Arteriovenosa/complicações , Derivação Arteriovenosa Cirúrgica/métodos , Veias Braquiocefálicas/patologia , Cateterismo Venoso Central/métodos , Diálise Renal/efeitos adversos , Adulto , Feminino , Humanos , Diálise Renal/métodos
7.
J Vasc Surg ; 71(2): 584-591.e1, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32040430

RESUMO

OBJECTIVE: Regional anesthesia (RA)-induced vasodilation increases the proportion of patients with vein anatomy suitable for arteriovenous fistula (AVF) creation. The functional outcomes of AVFs created with veins initially small for size on preoperative duplex ultrasound mapping (≤2.4 mm) that are recruited under RA have not been clearly defined. We aimed to evaluate freedom from revision or thrombosis, time to first cannulation, and reintervention rates of AVFs created with veins recruited after induction of RA. METHODS: A prospectively maintained quality improvement database from a single institution was queried for patients who had dialysis access created under RA. We compared AVFs created according to the original surgical plan (preoperative minimum vein diameter >2.5 mm) with AVFs recruited with RA (preoperative minimum vein diameter ≤2.4 mm). End points included freedom from revision or thrombosis, time to first cannulation, and reintervention rates. RESULTS: Between May 2014 and April 2018, there were 208 dialysis access cases performed under RA. Excluding grafts, revisions, patients with previous ipsilateral AVFs, and those without preoperative ultrasound vein mapping, 135 patients were included in our analysis. Induction of RA with intraoperative duplex ultrasound allowed a change in surgical plan in 55 of 135 (42%) patients (recruited with RA), including 31 patients originally scheduled for an arteriovenous graft (mean preoperative distal upper arm cephalic vein diameter of 1.8 mm [standard deviation, 0.2 mm]) who were converted to an AVF (12 brachiobasilic, 11 brachiocephalic, and 8 radiocephalic). The remaining patients in the group of AVFs recruited with RA included 13 scheduled for brachiobasilic configurations who were converted to brachiocephalic or radiocephalic AVFs and 11 scheduled for brachiocephalic AVFs who were converted to radiocephalic AVFs. Comparing AVFs created according to the original surgical plan vs AVFs recruited with RA, there were no differences in reintervention rates (48% vs 49%; P = .90) or functional outcomes at 6 months (60% vs 65% used on hemodialysis [P = .58] and 7% vs 2% primary failure [P = .19]). CONCLUSIONS: In this series, RA increased the proportion of patients who underwent AVF creation without compromising functional outcomes. Routine use of RA in access surgery could have significant implications in meeting national guidelines for autogenous access in the prevalent hemodialysis population.


Assuntos
Anestesia por Condução , Derivação Arteriovenosa Cirúrgica/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
9.
Am J Kidney Dis ; 75(1): 45-53, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31447072

RESUMO

RATIONALE & OBJECTIVE: Reducing turbulent blood flow through dialysis arteriovenous fistulas (AVFs) and radial stretching of their venous wall may attenuate hyperplasia and stenosis and improve AVF outcomes in hemodialysis patients. The goal of this study was to evaluate the safety and efficacy of the VasQ implant, which intervenes on these mechanisms by physically supporting the surgical arteriovenous anastomosis. STUDY DESIGN: Prospective, randomized, controlled, multicenter study. SETTINGS & PARTICIPANTS: 40 consecutive patients with kidney failure referred for creation of a brachiocephalic fistula in 4 vascular access centers in the United Kingdom and Israel. INTERVENTIONS: AVF surgical creation with placement of the VasQ implant (treatment) versus AVF placement without the implant (control). OUTCOMES: Safety assessed as percentage of severe device-related adverse events was the primary outcome. Secondary outcomes were efficacy assessments including: (1) AVF maturation at 3 months, defined as cephalic vein diameter≥5mm and flow≥500mL/min; (2) functional cumulative patency, defined as successful 2-needle cannulation for two-thirds or more of all dialysis runs for 1 month in study participants receiving dialysis; (3) cephalic vein diameter and blood flow; and (4) primary and cumulative patency at 6 months. RESULTS: No severe device-related adverse events were observed. There was no significant difference in maturation at 3 months or primary patency at 6 months between treatment and control (85% vs 80% and 80% vs 66%). Significantly larger vein luminal diameters were observed in the treatment group versus controls at 3 and 6 months (8.27±2.2 vs 6.69±1.8mm [P=0.03] and 9.6±2.5 vs 7.56±2.7mm [P=0.03]). Functional patency at 6 months was significantly greater in the treatment group (100% vs 56% [P = 0.01]). LIMITATIONS: Small sample size, limited power for secondary end points. CONCLUSIONS: No safety signals were detected for the VasQ external support of brachiocephalic AVFs. Higher functional patency and vein luminal diameters were achieved with the device at 3 and 6 months. VasQ may safely intervene on mechanisms associated with the disturbed hemodynamic profile in the juxta-anastomotic region. FUNDING: Funded by Laminate Medical Technologies Ltd. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT02112669.


Assuntos
Derivação Arteriovenosa Cirúrgica/instrumentação , Falência Renal Crônica/terapia , Implantação de Prótese , Diálise Renal , Idoso , Derivação Arteriovenosa Cirúrgica/métodos , Veia Axilar , Artéria Braquial/cirurgia , Constrição Patológica/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Grau de Desobstrução Vascular
10.
J Vasc Access ; 21(1): 105-109, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31328635

RESUMO

Non-maturation of arteriovenous fistulas is a frequent problem after dialysis access creation, especially in the forearm. The presence of accessory veins may play an important role in the non-maturing fistula. Several surgical and endovascular techniques are described to deal with this problem. We describe a new surgical technique in which we perform a rejoining of the arm veins to create a single large run-off vessel with greater diameter and flow for haemodialysis.


Assuntos
Braço/irrigação sanguínea , Derivação Arteriovenosa Cirúrgica/métodos , Diálise Renal , Veias/cirurgia , Adulto , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Grau de Desobstrução Vascular , Veias/diagnóstico por imagem
11.
J Vasc Access ; 21(1): 7-18, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30977412

RESUMO

BACKGROUND: Running out of vascular access for dialysis is thankfully rare, but despite this, most units will have a number of patients with few options and in a precarious state. The increasing longevity of dialysis patients portends more patients will reach minimal access options. End stage vascular access is poorly defined but classification may enable assessment and comparison of treatment options. Three options for patients with end stage access are a central venous catheter through a translumbar or transhepatic route, arterial-arterial prosthetic loop or a right atrial graft. AIMS: The aims of this study are to provide a structured review of evidence for these procedures to allow application and guide practice for patients with end stage vascular access. METHODS: A standardised search of published literature was performed of relevant studies. In addition, the references cited in those papers were assessed for any further available articles. All study types were included and reviewed by two authors independently. Primary outcomes were patient survival and secondary patency rate at 3 and 12 months. Secondary outcomes were long-term patency rates, mean time to cannulation and complications such as access dysfunction, thrombosis and infection. SUMMARY: Based on the available evidence, it would appear that arterial-arterial prosthetic loop is a definitive option for maintaining dialysis access in patients with no more arteriovenous access options. Translumbar and transhepatic dialysis catheters may offer short- and medium-term options and right atrial grafts may also be suitable as an option where arterial-arterial prosthetic loop is unsuitable.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Implante de Prótese Vascular/métodos , Cateterismo Venoso Central/métodos , Falência Renal Crônica/terapia , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Cateterismo Venoso Central/efeitos adversos , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Grau de Desobstrução Vascular , Adulto Jovem
12.
Eur J Vasc Endovasc Surg ; 59(2): 288-294, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31883684

RESUMO

OBJECTIVE: Arteriovenous grafts (AVGs) typically lose patency within two years of creation due to venous neointimal hyperplasia, which is initiated by disturbed haemodynamics after AVG surgery. Haemodialysis needle flow can further disturb haemodynamics and thus impact AVG longevity. In this computational study it was assessed how dialysis flow and venous needle positioning impacts flow at the graft-vein anastomosis. Furthermore, it was studied how negative effects of dialysis needle flow could be mitigated. METHODS: Non-physiological wall shear stress and disturbed blood flow were assessed in an AVG model with and without dialysis needle flow. Needle distance to the venous anastomosis was set to 6.5, 10.0, or 13.5 cm, whereas dialysis needle flow was set to 200, 300 or 400 mL/min. Intraluminal needle tip depth was varied between superficial, central, or deep. The detrimental effects of dialysis needle flow were summarised by a haemodynamic score (HS), ranging from 0 (minimal) to 5 (severe). RESULTS: Dialysis needle flow resulted in increased disturbed flow and/or non-physiological wall shear stress in the venous peri-anastomotic region. Increasing cannulation distance from 6.5 to 13.5 cm reduced the HS by a factor 4.0, whereas a central rather than a deep or superficial needle tip depth reduced the HS by a maximum factor of 1.9. Lowering dialysis flow from 400 to 200 mL/min reduced the HS by a factor 7.4. CONCLUSION: Haemodialysis needle flow, cannulation location, and needle tip depth considerably increase the amount of disturbed flow and non-physiological wall shear stress in the venous anastomotic region of AVGs. Negative effects of haemodialysis needle flow could be minimised by more upstream cannulation, by lower dialysis flow and by ensuring a central needle tip depth. Since disturbed haemodynamics are associated with neointimal hyperplasia development, optimising dialysis flow and needle positioning during haemodialysis could play an important role in maintaining AVG patency.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle , Modelos Cardiovasculares , Neointima/patologia , Diálise Renal/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Implante de Prótese Vascular , Cânula/efeitos adversos , Simulação por Computador , Desenho Assistido por Computador , Oclusão de Enxerto Vascular/etiologia , Humanos , Hidrodinâmica , Hiperplasia/etiologia , Agulhas/efeitos adversos , Fluxo Sanguíneo Regional/fisiologia , Diálise Renal/instrumentação , Diálise Renal/métodos , Estresse Mecânico , Grau de Desobstrução Vascular/fisiologia
13.
Medicine (Baltimore) ; 98(48): e18216, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770282

RESUMO

This study compared clinical outcomes of patient survival and arteriovenous fistula (AVF) patency between incident hemodialysis patients with and without type 2 diabetes mellitus (T2DM).Between January 2011 and December 2013, 384 consecutive incident hemodialysis patients with confirmed first upper-extremity AVF placement were divided into a T2DM group (n = 180, 46.9%) and a non-DM group (n = 204, 53.1%) and analyzed retrospectively. The primary outcome was all-cause mortality, and secondary outcome was AVF patency.Patients in the T2DM group had a higher prevalence of hypertension (P = .02), smoking (P < .01), cardiovascular disease (P < .01), history of cerebrovascular accident (CVA) (P < .01), and peripheral arterial occlusive disease (P < .01) than those in the non-DM group. On Kaplan-Meier survival analysis, the overall survival and AVF patency rates were significantly higher in the non-DM group relative to the T2DM group (both P < .01). In the adjusted model, older age (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.02-1.06; P < .01), T2DM (HR, 1.76; 95% CI, 1.12-2.77; P = .014), and history of CVA (HR, 1.76; 95% CI, 1.04-2.98; P = .04) were significantly associated with an increased risk of mortality. Older age and T2DM were independently associated with decreased primary (HR, 1.03; 95% CI, 1.02-1.04; P < .01, HR, 1.69; 95% CI, 1.22-2.33; P < .01, respectively) and secondary (HR, 1.03; 95% CI, 1.01-1.04; P < .01, HR, 2.07; 95% CI, 1.42-3.00; P < .01, respectively) AVF patency during follow-up.Compared with patients in the non-DM group, patients in the T2DM group had a higher mortality rate and worse AVF patency rates.


Assuntos
Derivação Arteriovenosa Cirúrgica , Diabetes Mellitus Tipo 2 , Falência Renal Crônica , Diálise Renal , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Comorbidade , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Diálise Renal/mortalidade , Estudos Retrospectivos , Medição de Risco , Grau de Desobstrução Vascular
14.
Khirurgiia (Mosk) ; (11): 24-28, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31714526

RESUMO

OBJECTIVE: To study the causes of recirculation syndrome and optimize surgical correction. MATERIAL AND METHODS: There were 2329 procedures of formation and restoration of permanent vascular access in 2109 patients for the period from 1998 to 2018. Recirculation syndrome occurred in 66 (3.1%) patients. Instrumental diagnosis of the causes of recirculation syndrome included Doppler ultrasound of permanent vascular access (100%) and angiography in accordance with indications. All patients were divided into 4 groups. The first group included 39 (59.1%) patients with native arteriovenous fistula. The second group included 12 (18.2%) patients with high arteriovenous fistula (between the brachial artery and the cephalic vein). The third group included 10 (15.1%) patients with major vein transposition. Synthetic prosthesis to create an arteriovenous fistula was used in the fourth group (n=5, 7.6%). RESULTS: In the first group, recirculation syndrome was caused by the presence of a large branch in close proximity to the arteriovenous anastomosis, its combination with significant stenosis of the anastomosis, hypoplasia of the outflow pathways of the fistulous vein. In the second group, the reasons were subclavian vein stenosis and dilated tributaries of the saphenous veins. In the third group, the main cause of recirculation syndrome was major vein stenosis in the upper third of the shoulder. In the fourth group, recirculation syndrome was caused by stenosis of the prosthetic-venous anastomosis. CONCLUSION: Recirculation syndrome in hemodialysis patients is usually caused by malfunction of permanent vascular access. Ultrasound or angiography may be successfully used to diagnose dysfunction. Effective treatment of this problem implies surgical or endovascular correction of permanent vascular access.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Constrição Patológica/complicações , Falência Renal Crônica/terapia , Diálise Renal , Derivação Arteriovenosa Cirúrgica/métodos , Humanos , Fluxo Sanguíneo Regional , Síndrome , Resultado do Tratamento , Grau de Desobstrução Vascular , Veias/patologia
15.
Rev Port Cir Cardiotorac Vasc ; 26(3): 229-233, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31734978

RESUMO

Creating and maintaining a functional vascular access (VA) is a critical factor in the survival of a dialysis patient. It implies a creative attitude either to maintain its functionality or to build a new one wherever possible, being it autologous or synthetic. We describe the VA history of a 59 years-old male patient, with extreme obesity, which started in 2012 with failed attempts of VA construction in both forearms until a functional brachiocephalic arteriovenous fistula (AVF) in the right upper limb was achieved. However, it required ligation due to severe venous hypertension secondary to central venous disease related to previous CVC use. As he had no good superficial conduit in the left arm we decided to harvest the arterialized right cephalic vein and implant it in the left arm, creating an autologous arteriovenous shunt between the brachial artery and axillary vein (AV). Despite initial patency, it failed irreversibly approximately one year after creation. As no more superficial veins were available in the upper limbs, a prosthetic access was the next step. We decided for a hybrid graft (HG) between the left brachial artery and the AV because of the patient's biotype and scarred axilla that impeded a safe re-intervention on the AV. This graft was used between 2015 and 2017 with multiple interventions to maintain patency. In 2017 a significant diffuse prosthesis deterioration and reduced AVF flow were noticed with no possible segmental reconstruction. We were then forced to proceed with subtotal graft substitution preserving the outflow stented segment of the HG, using an early cannulation graft to prevent CVC use. After this successful reconstruction, the patient started hemodialysis on the following day with no intercurrences registered.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Oclusão de Enxerto Vascular/cirurgia , Falência Renal Crônica/terapia , Falha de Prótese/efeitos adversos , Diálise Renal , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
16.
Clin Ter ; 170(6): e454-e459, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31696909

RESUMO

AIMS: The radio-cephalic arteriovenous fistula (RCAVF) is the first choice treatment in end-stage renal disease patients. In the last few years, the hemodialysis population has shown a high percentage of elderly patients (> 65 year old) with comorbidities, mainly vascular diseases, which may adversely affect their vascular access success. The aim of this study was to evaluate the effectiveness of a loup-assisted technique to create RCAVFs in over 65 patients. PATIENTS AND METHODS: 98 consecutive patients with renal failure were prospectively observed. The patient were divided in relation to their age (> 65 year old; < 65 year old). In both groups, a microsurgical distal RCAVF was created. Statistics included the prevalence of distal RCAVF created, the incidence of immediate failure, the primary and secondary patency rate at one year. RESULTS: Distal RCAVF was created in 82.60% of patients younger than 65 years and in 73.07% of patients older than 65 years, with no statistically significant difference. The incidence of immediate failure, the primary and secondary patency at one year were not statistically significant between the two groups. CONCLUSIONS: Distal RCAVF should be the first choice vascular access even in ESRD elderly patients. The loup-assisted microsurgical fistula creation, allows to perform distal RCAVF with success, even in patients older than 65 years old, achieving similar results to younger patients.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Feminino , Humanos , Falência Renal Crônica/cirurgia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Diálise Renal , Resultado do Tratamento
19.
Medicine (Baltimore) ; 98(40): e17238, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577715

RESUMO

INTRODUCTION: Arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis due to its higher patency and lower infection rate. However, its suboptimal maturation rate is a major weakness. Although substantial risk factors for AVF maturation failure have been disclosed, modifiable risk factors remain unknown. During the AVF maturation process, an elevated luminal pressure is required for outward remodeling; however, excessively high luminal pressure may also be detrimental to AVF maturation, which remains to be defined. We hypothesized that higher AVF luminal pressure is harmful to its maturation, and investigate its potential as a modifiable factor to improve AVF maturation. METHODS AND ANALYSIS: This prospective study includes patients undergoing surgical creation for a native AVF. The exclusion criteria were as follows: age <20 years, inability to sign an informed consent, and failure to create a native AVF due to technical difficulties. Demographic and laboratory profiles will be collected before AVF surgery. Vascular sonography will be performed within 1 week of AVF creation to measure the diameters, flow rates, and flow volumes of AVF and its branched veins. The pressure gradient within AVF will be estimated from the blood flow rates using the modified Bernoulli equation. The primary outcome is spontaneous AVF maturation defined as provision of sufficient blood flow for hemodialysis within 2 months of its creation without any interventional procedures. The secondary outcome is assisted AVF maturation, which is defined as AVF maturation within 2 months from its creation aided by any interventional procedure before the successful use of AVF. DISCUSSION: While contemporary theory for AVF maturation failure focuses on disturbed wall shear stress, complicate assumptions and measurement preclude its clinical applicability. AVF luminal pressure, which may be manipulated pharmaceutically and surgically, may be a target to improve the outcome of AVF maturation. TRIAL REGISTRATION: This study has been registered at the protocol registration and results system. The Protocol ID: NCT04017806.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Diálise Renal/métodos , Grau de Desobstrução Vascular/fisiologia , Remodelação Vascular/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Fumar Cigarros/epidemiologia , Comorbidade , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal/etiologia , Insuficiência Renal/terapia , Projetos de Pesquisa , Fatores de Risco , Fatores Sexuais , Taiwan , Fatores de Tempo , Adulto Jovem
20.
Eur J Vasc Endovasc Surg ; 58(5): 756-760, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31540795

RESUMO

OBJECTIVE: The aim was to evaluate the safety and feasibility of endoscopic superficialisation (ES) in patients with deeply located cephalic veins in well matured arteriovenous fistulae (AVF) and to present functional outcomes. METHODS: All patients with cannulation difficulties due to a deep lying cephalic vein of more than 6 mm but with an otherwise matured AVF with a straight needle access segment of at least 6 cm were included in this retrospective study. Procedure related safety, defined as completion of ES with no need for conversion to open surgery, and feasibility in terms of cephalic vein depth reduction were assessed. The primary endpoint was three successfully performed haemodialysis sessions using the endoscopically superficialised AVF during a minimum follow up of 12 months. RESULTS: From June 2013 to August 2017, 12 patients with a mean body mass index of 33.5 ± 3.9 kg/m2 underwent ES as a second stage procedure following radiocephalic (n = 5) or brachiocephalic AVF (n = 7) creation. All procedures were conducted endoscopically. Ultrasound imaging 12 weeks post-operatively documented a reduction in the depth of the cephalic vein from a mean of 10.1 ± 1.4 mm to 4.3 ± 0.8 mm. The mean duration of the ES was 69 ± 26.0 min with 67% performed under locoregional anaesthesia. In all but one patient with a cephalic vein of poor wall quality leading to recurrent haematoma, haemodialysis was performed successfully following ES. CONCLUSIONS: Endoscopic superficialisation of the cephalic vein is a safe and effective technique. Providing good functional results, ES represents an alternative approach for second stage superficialisation in obese patients.


Assuntos
Braço/irrigação sanguínea , Derivação Arteriovenosa Cirúrgica/métodos , Cateterismo/efeitos adversos , Procedimentos Endovasculares/métodos , Obesidade , Diálise Renal , Insuficiência Renal Crônica , Veias/cirurgia , Idoso , Índice de Massa Corporal , Cateterismo/métodos , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/diagnóstico , Diálise Renal/efeitos adversos , Diálise Renal/instrumentação , Diálise Renal/métodos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Suíça , Resultado do Tratamento , Dispositivos de Acesso Vascular/efeitos adversos
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