Which femoral neck for a dual mobility cup? A biomechanical evaluation.

PURPOSE: This study aimed to evaluate polyethylene (PE) damage and wear lesions to the chamfer of mobile components under mobile and fixed femoral neck impingement at the third articulation, and to determine which femoral neck characteristics should be considered with a dual mobility cup to limit those lesions. METHODS: Two femoral neck geometries (cylindrical and quadrangular) with two surface finishing roughness (rough and polished), and two head-to-neck ratios (28- and 22.2-mm diameter femoral heads) were evaluated in a hip simulator testing. For each characteristic, six femoral necks were tested with six dual mobility cups under fixed and mobile femoral neck impingement conditions. Chamfer PE damage and volumetric wear were evaluated and compared for each femoral neck characteristic and impingement condition. RESULTS: Under mobile impingement condition, femoral neck characteristics did not significantly affect PE damage and wear lesions to the chamfer (p = 0.283 to 0.810). However, under fixed impingement condition, significantly higher PE damage and wear lesions to the chamfer were produced by the quadrangular geometry compared to the cylindrical geometry (p = 0.004 to 0.025). In addition, with the quadrangular geometry, rough surface finishing was demonstrated to increase volumetric wear of the chamfer (p = 0.009). No significant influence of head-to-neck ratio was observed on PE damage and wear lesions to the chamfer (p = 0.244 to 0.714). DISCUSSION: This biomechanical study emphasized that femoral neck characteristics are critical with dual mobility cup and tend to favor a cylindrical geometry particularly whether fixed impingement at the third articulation occurs.

Interventional nephrology in Puerto Rico: a four year experience.

Puerto Rico is one of the most prevalent areas covered by Medicare in need of renal replacement therapy for which interventional procedures are performed. A cumulative analysis of this management is reported in patients during the period between June 2007 and August 2010. Experience accumulated with 3755 surgical patients revealed that 58% had intravascular catheters, 28% had arteriovenous fistulas, 15% had arteriovenous grafts, and 2% without vascular access. Procedures performed in these patients were: catheter introduction in 1990 cases (33%), angioplasty in 751 cases (20%), angiography in 450 cases (12%), thrombectomy in 413 cases (11%) and venous mapping in 151 cases (4%). The success rates of these procedures were evaluated by analysis of the Society of Interventional Radiology (SIR) criteria for Lifeline Vascular Access. Using SIR definition of success rate for at least one session that includes "declots", placement of catheters and angioplasty, our results revealed an average of 98.2% overall success rate greater than the standard value KDOQI/SIR (> 85% ). This study has documented for four years the success rate of Vascular Interventional Nephrology Center at Auxilio Mutuo Hospital. In order to maintain this success rate is necessary to further evaluate its effectiveness and, most importantly, the development of an educational program for vascular access in patients with chronic kidney disease prior to placement in dialysis units.

Anemia management among hemodyalisis patients at the University Hospital in Puerto Rico.

End-stage renal disease is frequently complicated with anemia. Iron deficiency anemia occurs in most hemodialysis patients secondary to increased iron demand driven by the accelerated erythropoiesis that occurs when stimulating agents are administered as treatment of the anemia. The purpose of this study was to determine the prevalence of anemia and iron stores in patients undergoing hemodialysis at our unit; identify their treatment and effectiveness. Medical records of fifty-three patients undergoing ambulatory hemodialysis were evaluated for three months. Patient's hemoglobin, ferritin, iron, total iron binding capacity and percent transferrin saturation were recorded. 91% patients had arterial hypertension and 62% were diabetic. The prevalence of anemia was 34%, 57% and 47% during the three-month period respectively. Only 21% of the population had transferrin saturation less than 20% and none had ferritin below 200 ng/ml. Throughout the study, the majority of patients were managed with combination of iron and erythropoietin stimulating agents (ESAs). The prevalence of anemia remained elevated despite treatment with iron and ESAs. However, 56% of anemic patients throughout the three months showed an increase in hemoglobin levels by the end of the observation period. 53% of patients were treated with iron alone or with ESAs for the three consecutive month periods and only two had transferrin saturation less than 20%. In our population, ESAs low responsiveness is not related to iron deficiency but to the morbidity of their disease.

[Brain death, physiopathology, optimal care and hormonal therapy for cardiac donation]. / Muerte encefálica, fisiopatología, cuidado óptimo y terapia hormonal para donación cardíaca.

Heart transplantation goes on leading the standard therapy for the terminal heart failure. The success of this procedure and the post-transplantation survival, meaning during the perioperative time, is variable because of the good performance of the donor graft, due to this situation, the pre-harvesting evaluation is very important. The brain death brought many changes: 1) first of all the "adrenergic storm" with its hemodynamic and cardiac dangerous events; 2) Thyroidal hormones, cortisol, vasopressin, and seric insulin depletion with its metabolic consequences respectively. Since 2002 during the Crystal Consensus started the using of the hormonal therapeutic with triyodothironine, vasopressin and metilprednisolone for improving, meaning those limitrophes ones, the performance donor hearts with brain death, and the goal has been to harvest more donated organs en quality and numbers. This hormonal therapeutic has had great acceptation and is successful; having more harvesting of solids organs: hearts, lungs and kidneys; with more performance and surviving at 1 year post-transplantation and less mortality. Our Hospital began the hormonal therapeutic since January 2011with excellent results. On this basis we can concluded that, hormonal rescue therapy, improves the availability and performance of organs for transplantation.

Intracardiac malignant fibrous histiocytoma. A case report.

BACKGROUND: Primary cardiac tumors are rare forms of cardiac disease. The reported incidence varies between 0.002 and 0.3%; 25% of these tumors are malignant, usually a variant of sarcoma. Malignant fibrous histiocytoma constitutes <3% of primary cardiac tumors. CLINICAL CASE: We review the case of a 53-year-old female who presented with congestive heart failure and pleural effusion. Transthoracic echocardiography and chest computed tomography revealed cardiac tumor involving the left atrium. Tumor was excised surgically and histologically proven to be a malignant fibrous histiocytoma, primarily confined to the heart. During the immediate postoperative evolution, the patient presented left pleural effusion for 2 weeks. The patient was referred to Oncology Service for complementary treatment. CONCLUSION: Malignant fibrous histiocytoma is a rare tumor and, in this case, prognosis is reserved.

[Distant heart procurement for transplantation]. / Procuración a distancia de corazóncon fines de trasplante.

BACKGROUND: The low availability of organ donors is a serious hindrance to heart transplantation. Long-distance organ procurement has been accepted as an option despite longer ischemic time for the heart. METHODS: Long-distance procurement from outside Mexico City in adult patients with terminal heart failure submitted to orthotopic heart transplantation between February 1st 2011, and January 31st 2012, was assessed. Ischemic time, distance from Mexico City, and perioperative and short-time mortality were determined. RESULTS: There were 14 orthotopic heart transplants during the analyzed period. In 12 cases long-distance heart procurement was required. Mean age of recipients was 42.7 years (range between 17 and 61 years). Seven patients were male and five female. Mean ischemic time was 228.58 minutes. The longest distance of procurement for land and air travel was 2,319 km; and the lowest, 22.5 km. Perioperative mortality was 8.33% (one patient), and there were 2 short-term deaths due to non-cardiac complications. In this series we included a case of heart-kidney transplantation from same donor. CONCLUSION: At our hospital, long-distance procurement for heart transplantation is a useful procedure with good results.

Retiro de "Stents" intracoronarios y cirugía de revascularización miocárdica / Retirada de "Stents" intracoronários e irurgia de revascularização miocárdica / Intracoronay “stents” removal and coronary artery Bypass grafting surgery

Introducción: es cada vez más frecuente la necesidad de retirar “stents” en la cirugía de revascularización. Material y métodos: serie de casos en los que se realiza endarterectomía y retiro de “stents” de vasos coronarios entre el 1 de enero y el 30 de abril del 2011. Se analizó morbilidad, antecedentes y evolución. Resultados: tres pacientes requirieron remoción de “stents”, dos de la descendente anterior y uno de la coronaria derecha, un paciente con infarto del miocardio falleció por choque cardiogénico. Conclusión: La remoción de “stents” en cirugía de revascularización debe considerar se como opción terapéutica en casos bien determinados.

Introdução: Cada vez é mais frequente a necessidade de retirar “stents” na cirurgia de revascularização. Material e métodos: série de casos onde são realizadas endarterectomia e retirada de“stents” de artérias coronárias entre 1 de janeiro e 30 de abril de 2011. Analisou-se morbilidade, antecedentes e evolução. Resultados: três pacientes tiveram remoção de “stents”, dois da artéria descendente anterior e um da coronária direita, um paciente com infarto do miocárdio faleceu por choquecardiogênico. Conclusão: A remoção de “stents” em cirurgia de revascularização deve considerar-se como opção terapêutica em casos bem determinantes.

Introduction: Stent removal is associated to coronary artery by-pass surgery is a more fre-quent procedure. Material and Methods: We present the cases that required endarterectomy, stent removal and coronary artery by-pass surgery between January 1, 2011, and April 30, 2011. We analyzedmedical history, morbidity, and evolution.Results: Three patients required stents removal, two in coronary anterior descending artery and one on right coronary artery. One patient with acute myocardial infarction died, due tocardiogenic shock. Conclusion: It was concluded that stent removal in coronary artery by-pass surgery shouldbe considered as a surgical option in selected cases.

La radiografía de tórax en el diagnóstico de padecimientos óseo en pediatría / The radiographic of chest in the bony diagnosis of sufferings in pediatric

Se seleccionaron 28 diferentes patologías del archivo de enseñanza y de la práctica diaria del Hospital Nacional de Niños de San José, Costa Rica, que estuvieran relacionados con procesos infecciosos, tumorales, diferentes síndromes, desordenes metabólicos y displasias óseas. Se agruparon por periodos de edad que van desde el recién nacido al adolescente para facilitar al radiólogo y al pediatra la orientación hacia las diferentes patologías óseas en relación directa con el desarrollo del niño. Se tabuló solo un padecimiento por periodo de edad, pues algunos por su evolución natural como la osteopetrosis, osteogénesis imperfecta, acondroplasia, etc., se repiten a diferentes edades.