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1.
Materials (Basel) ; 15(7)2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35408024

RESUMEN

A novel elevated-temperature and high-pressure in situ punch-shear-test cell was developed to qualify materials for reliable service in harsh environments representative of those typically encountered in oil and gas operations. The proposed modular and compact test device is an extension of the ASTM D 732 punch-shear method. Conventionally, materials are first exposed to harsh environments, then removed from the aging environment for mechanical testing. This practice can lead to the generation of unrealistic (often optimistic) mechanical properties. This is especially true in the case of materials for which fluid ingress is reversible. The present contribution elaborates on the developed in situ punch-shear device that has been successfully used to realistically assess the tensile yield strength and modulus properties of in-service polymer materials based on experimentally established correlations between shear and tensile tests.

2.
Pediatr Cardiol ; 42(7): 1539-1545, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34081172

RESUMEN

Perimembranous ventricular septal defect closure in small infants has traditionally been a surgically treated defect, although alternative hybrid strategies are emerging. We aim to describe a novel approach to retrograde device closure of clinically relevant perimembranous ventricular septal defects in small infants via carotid cutdown. A retrospective review of all patients managed with attempted carotid cutdown for device closure of a perimembranous ventricular septal defect was recorded at a single tertiary cardiac centre. We summarized data on successful device deployment, conversion to open repair, complications, and length of stay. Eighteen infants with median (IQR) age of 7 months (5-9 months) and weight of 7.1 kg (6.5-7.8 kg) with clinically relevant PMVSD underwent attempted retrograde closure via carotid cutdown. Median (IQR) defect size was 8 mm (7-9 mm). Successful device deployment without significant aortic or tricuspid valve interference occurred in 15 (83%) patients. Three patients were converted to open repair, one following damage to the tricuspid valve apparatus. Median (IQR) hospital stay was 1 day (1-3 days). There were no complications related to carotid cutdown. Retrograde device closure of hemodynamically significant PMVSD is feasible and effective in small infants. Decision to convert to surgical repair should be made early if suboptimal device placement occurs. Carotid evaluation should be performed to rule out any access-related complications.


Asunto(s)
Defectos del Tabique Interventricular , Dispositivo Oclusor Septal , Cateterismo Cardíaco , Defectos del Tabique Interventricular/cirugía , Humanos , Lactante , Estudios Retrospectivos , Resultado del Tratamiento , Válvula Tricúspide
3.
Pediatr Cardiol ; 42(3): 526-532, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33263794

RESUMEN

The hybrid subxiphoid perventricular approach provides direct access through the heart and may alleviate the technical limitations of complex percutaneous interventions particularly in infants with low body weight. We present the outcomes from a tertiary cardiology center using this approach. We performed a retrospective review of all patients less than 15 kg who underwent a hybrid perventricular approach via a small subxiphoid incision. Medical records were reviewed to obtain clinical, demographic and outcome data. Seventeen patients underwent 18 hybrid perventricular procedures using a subxiphoid approach. Median age at time of procedure was 4.6 months (IQR = 1.6 to 18 months) and median weight was 6.2 kgs (IQR = 3.4 to 8.6 kgs). Six patients underwent hybrid pulmonary valve replacement (PVR), 5 patients underwent pulmonary outflow stenting, and 5 infants underwent hybrid ventricular septal defect (VSD) device closure. One patient with a single ventricle who did not tolerate a percutaneous approach underwent left pulmonary artery (LPA) stenting for severe LPA coarctation with subsequent right ventricular outflow tract (RVOT) stenting. One further patient underwent implantation of a larger diameter stent for pulmonary artery bifurcation stenosis. Procedure success rate was 89% with two of the VSD cases reverted to open surgical repair. There were no intra-procedural complications; however, one patient died within 72 h. Minor adverse events occurred in 2 patients including a wound infection in one patient with an immunodeficiency syndrome. Hybrid subxiphoid perventricular approach provides an excellent alternative access to the heart especially in low birth weight infants to prevent hemodynamic instability or in small children requiring large delivery sheaths.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Cardiopatías Congénitas/cirugía , Ventrículos Cardíacos/cirugía , Cateterismo Cardíaco/métodos , Femenino , Defectos del Tabique Interventricular/cirugía , Humanos , Lactante , Masculino , Arteria Pulmonar/cirugía , Estudios Retrospectivos , Dispositivo Oclusor Septal , Estenosis de Arteria Pulmonar/cirugía , Stents , Factores de Tiempo , Resultado del Tratamiento
4.
Eur J Cardiothorac Surg ; 59(4): 823-830, 2021 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-33253364

RESUMEN

OBJECTIVES: Hybrid approach to pulmonary valve replacement (PVR) in the paediatric population has been reported, although data in infants and small children are limited. Several strategies are now possible. The aim of this study is to review our hybrid PVR strategy in a complex patient cohort, outlining a variety of approaches employed in our centre. METHODS: We performed a retrospective review of infants and small children who underwent hybrid PVR between May 2017 and April 2019 in a single tertiary cardiology centre. Medical records were reviewed to ascertain demographic, clinical and outcome data. RESULTS: Ten patients with a median (interquartile range) age of 1.5 years (1.1-1.9) and weight of 8.8 kg (8-10.6) were managed with hybrid pulmonary valve insertion. Eight patients had perventricular approach (4 sternotomy and 4 subxiphoid) and 2 patients had surgically sutured valve. Six patients underwent cardiopulmonary bypass for associated lesions. Three had insertion of the valve into conduits and 7 were deployed into native right ventricular outflow tracts. The pulmonary valve was successfully inserted in all 10 patients with no mortality. Postprocedural complications included paravalvar leak in 2 patients, suspected endocarditis in 1 patient who developed early valve regurgitation and wound infection in 1 patient. CONCLUSIONS: Several approaches to hybrid PVR may be employed in small children with a high success rate. Follow-up studies are required to evaluate longer term durability of these approaches compared to standard surgical replacement.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Enfermedades de las Válvulas Cardíacas , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Pulmonar , Válvula Pulmonar , Cateterismo Cardíaco , Niño , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Lactante , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Insuficiencia de la Válvula Pulmonar/diagnóstico por imagen , Insuficiencia de la Válvula Pulmonar/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
5.
Arts Health ; 11(3): 232-245, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31038434

RESUMEN

Background: This paper draws on a longitudinal study exploring the outcomes of an arts referral programme in General Practice in the South West of England since 2009. It focuses on the qualitative responses of the patient cohort Methods: Using qualitative methods and thematic analysis, this paper explores and considers the responses from n = 1297 participants who provided feedback from an open-ended questionnaire on self-reported benefits of the arts referral programme. Results: Participant reactions demonstrate that the programme provided a range of personal and social benefits rarely considered or explored in comparative studies. The analysis suggests participants were able to self-manage aspects of their health-related conditions, and were able to make progress towards a better physical and/or mental health. Conclusions: The evidence suggests that arts-based referral programmes, have a range of benefits for participants that may not have been fully appreciated. The consequences on self-management requires further investigation.


Asunto(s)
Arteterapia , Trastorno Depresivo/rehabilitación , Humanos , Estudios Longitudinales , Evaluación de Programas y Proyectos de Salud , Autoinforme , Encuestas y Cuestionarios
6.
J Thorac Cardiovasc Surg ; 141(3): 803-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20708753

RESUMEN

OBJECTIVES: Neutrophil infiltration of tissues as part of the inflammatory response to cardiac surgery is one of the major mediators of postoperative multiple-organ dysfunction. Omega-3 fatty acids markedly attenuate endothelial cell inflammatory responses, including upregulation of neutrophil adhesion molecules. The efficacy of a clinically safe form of omega-3 to produce this effect in vivo was examined. METHODS: Rat gut intravital microscopic analysis was used to visualize neutrophil transmigration from the microcirculation into the tissues of the gut. Inflammatory activation was in the form of 30 minutes of ischemia and 90 minutes of reperfusion. Sham, control (0.9% saline infusion over 4 hours), and omega-3 (Omegaven [Fresenius Kabi, Bad Homburg, Germany] infusion over 4 hours) pretreatments were compared. RESULTS: Ischemia-reperfusion resulted in a 4-fold increase in neutrophil adherence to the endothelium (baseline: 4.3 ± 0.2 vs control group: 19.2 ± 3.5 adherent neutrophils per 100 µm, P < .01), which intravenous omega-3 suppressed (7.8 ± 1.7 adherent neutrophils per 100 µm, P < .01). Omega-3 pretreatment also reduced neutrophil transmigration into the tissues after reperfusion (sham group: 6.3 ± 0.8 vs control group: 13.2 ± 1.4 vs omega-3 group: 9.4 ± 0.9 neutrophils per field, P = .037). Gut tissue levels of the neutrophil-released enzyme myeloperoxidase were similarly markedly reduced with omega-3 pretreatment (sham group: 10.5 ± 1.6 vs control group: 19.0 ± 3.3 vs omega-3 group: 10.1 ± 1.2 U/g, P = .03). CONCLUSIONS: Four hours' pretreatment with a relatively safe form of intravenous omega-3 suppressed neutrophil adherence and tissue infiltration, resulting in lower levels of the tissue-damaging enzyme myeloperoxidase. This suggests a possible strategy for diminishing postoperative multiple-organ dysfunction.


Asunto(s)
Antiinflamatorios/administración & dosificación , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Endotelio Vascular/efectos de los fármacos , Ácidos Grasos Omega-3/administración & dosificación , Inmunidad Innata/efectos de los fármacos , Intestinos/irrigación sanguínea , Neutrófilos/efectos de los fármacos , Daño por Reperfusión/prevención & control , Animales , Adhesión Celular/efectos de los fármacos , Endotelio Vascular/inmunología , Infusiones Intravenosas , Rodamiento de Leucocito/efectos de los fármacos , Masculino , Microscopía por Video , Activación Neutrófila/efectos de los fármacos , Infiltración Neutrófila/efectos de los fármacos , Neutrófilos/enzimología , Neutrófilos/inmunología , Peroxidasa/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/etiología , Daño por Reperfusión/inmunología , Factores de Tiempo
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