Guía de acceso vascular en hemodiálisis / Vascular access guideliness for hemodialysis

Introducción. La calidad del acceso vascular (AV) condiciona los resultados clínicos de los enfermos tratados mediante hemodiálisis periódicas. Las complicaciones originadas por la disfunción del AV constituyen una de las principales causas de morbimortalidad de estos pacientes y contribuyen de forma sustancial al aumento del coste sanitario. La Sociedad Española de Nefrología considera que este problema requiere una atención prioritaria, y ha decidido realizar una revisión de las guías de actuación de este capítulo, con la finalidad de mejorar nuestros estándares colectivos y elevar la calidad de nuestra práctica asistencial. Objetivos. La finalidad esencial ha sido la de elaborar un informe que pueda proporcionar una ayuda para la comprensión y tratamiento de los problemas relacionados con el AV y obtener una homogeneización de actuaciones con el propósito de alcanzar tres objetivos principales: aumentar la utilización de fístulas arteriovenosas autólogas como AV inicial, detectar la disfunción de AV permanente antes de la trombosis y racionalizar la utilización de catéteres venosos centrales (CVC). Desarrollo y conclusiones. Se presenta un documento consensuado de forma multidisciplinar en la que han participado nefrólogos, cirujanos vasculares, radiólogos intervencionistas, especialistas en enfermedades infecciosas y diplomados en enfermería nefrológica. En él se define el estado de la situación en seis capítulos: preparación del paciente, creación del AV, cuidados, vigilancia, tratamiento de las complicaciones y CVC. Estas guías constan de una serie de enunciados con diferentes grados de evidencia según la literatura disponible, que no pretenden ser normas de obligado cumplimiento, sino referentes del estado actual del problema y sus soluciones. La práctica clínica diaria, al depender de las condiciones intrínsecas, no siempre nos permite alcanzar el ideal, pero sí dirigir nuestros esfuerzos a una mejora de resultados. Cada recomendación se complementa con la exposición de su razonamiento. El documento se acompaña de una serie de indicadores de calidad

Introduction. Quality of vascular access (VA) has aremarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Aims. Spanish Society of Nephrology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. Development and conclusions.We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care ,monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to take aproppiate decissions. Several quality standars are also included

[Vascular access guidelines for hemodialysis]. / Guías de acceso vascular en hemodiálisis.

Quality of vascular access (VA) has a remarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Spanish Society of Neprhology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care, monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to make aproppiate decissions. Several quality standars are also included.

[Vascular access in Spain: analysis of its distribution, morbidity, and monitoring systems]. / El acceso vascular en España: análisis de su distribución, morbilidad y sistemas de monitorización.

Vascular access disfunction causes a therapeutic emergency with different implications in patients and care givers. The aim of this study was to know the distribution of different kinds of vascular access between prevalent hemodialysis patients, the proportion of incident patients that holds a permanent vascular access, the monthly hospital ratio for access repair and the use of surveillance systems of vascular access adequacy in the different Centers. This is a National survey that shows results of a questionnaire sent to all hemodialysis units in Spain on september 1999. Eighty-eight units answered the questionnaire (42%) providing information about 5,476 prevalent patients. Of these patients, 81% receives treatment through an arteriovenous fistula, 10% uses a central catheter and 9% a graft. Only 56% of incident patients have a permanent vascular access. Reasons for catheter use between prevalent patients were exhaustion of vascular sites in 42%, maduration of permanent access in 24%, thrombosis of the access in 14% and another reasons in 19%. Patients monthly hospitalization ratio for vascular repair was 3%, that might represent more than 5,600 hospital ingress by year. More than 80% of the Units releases different surveillance programs of access adequacy, 69% by fiscal detection problems, 47% by dynamic alterations and 18% by dilution and imaging procediments. The conclusions of this survey are that arteriovenous fistula is the most used vascular access in Spain. Almost half of the patients do not have vascular access in use for the beginning of hemodialysis. Exhausted vascular sites is the primary reason for central catheter using. A great proportion of Units are employing programs for access monitoring.

El acceso vascular en españa: análisis de su distribución, morbilidad y sistemas de monitorización / Vascular access in Spain: distribution, morbidity and surveillance systems

La disfunción del acceso vascular constituye una emergencia terapéutica que ocasiona diferentes tipos de repercusión entre pacientes y profesionales.El objetivo del presente estudio es el de conocer la distribución de las diferentes modalidades de acceso vascular entre la población en programa de hemodiálisis periódicas en España, la proporción de enfermos que disponen de un acceso vascular permanente en el momento de iniciar el tratamiento, la tasa de ingresos hospitalarios que originan las complicaciones del acceso vascular y la implantación de sistemas de monitorización sobre la función del mismo.Se analizan los datos de un cuestionario remitido a todas las Unidades de Diálisis según censo de un catálogo internacional y se obtienen los siguientes resultados: sobre una muestra de 5.472 pacientes el 81 por ciento se dializan mediante una fístula arteriovenosa, el 10 mediante un catéter y un 9 por ciento emplea un injerto. El 44 por ciento de los pacientes no disponen de acceso vascular permanente en el momento de iniciar el tratamiento. El 42 por ciento de los pacientes que emplea catéteres es debido al agotamiento de la red venosa para proceder a la implantación de nuevos accesos, un 24 por ciento porque su fístula está en período de maduración, un 14 por ciento porque su acceso se ha trombosado y está pendiente de reparación y un 19 por ciento por otras razones. La tasa de ingresos para reparar disfunciones es del 3 por ciento de pacientes/mes lo que representa más de 5.600 hospitalizaciones a nivel nacional por este concepto. El 80 por ciento de las Unidades realiza monitorización sistemática del funcionamiento del AV: 69 por ciento emplea parámetros físicos, el 47 por ciento dinámicos y el 18 por ciento técnicas de imagen y dilución.El 71 por ciento de las Unidades utiliza al menos un sistema de monitorización, más del 50 por ciento de las Unidades utiliza dos sistemas conjuntos, y un 9 por ciento realiza los tres sistemas de control.Se concluye del presente estudio que la fístula arteriovenosa es el acceso vascular que se utiliza de forma preferente en España. Cerca de la mitad de los pacientes no disponen de acceso permanente en el momento de iniciar la hemodiálisis. El agotamiento de la red venosa es la causa más frecuente de la utilización de catéteres. La disfunción del acceso provoca una tasa significativa de ingresos.La Mayoría de las Unidades del país emplean sistemas de monitorización del acceso vascular. (AU)

[Changes in hospital mortality from acute myocardial infarction during the last 15 years. The impact of reperfusion treatments]. / Evolución de la mortalidad hospitalaria por infarto agudo de miocardio durante los últimos 15 años. Influencia de los tratamientos de reperfusión.

INTRODUCTION AND OBJECTIVES: There are not any conclusive data about the changes in in-hospital mortality in a non-selected series of patients admitted with acute myocardial infarction in different periods of time. We studied the in-hospital mortality of three extensive series of patients admitted to our Coronary Care Unit during different periods of time, the influence of reperfusion methods and their early application, as well as the changes in baseline characteristics of the three populations studied. METHODS: The in-hospital mortality of 1,858 consecutively-admitted patients during three different periods of time (1983-1986, 1992-1994, and 1995-1998) were studied. The demographic data, the previous history and risk factors, the evolution during the acute phase and the treatment prescribed with special attention to the reperfusion methods applied and the delay on its administration were compared. RESULTS: The differences in the baseline characteristics of the populations studied are described. In the two groups of the nineteen-nineties, an increase in the age and in the percentage of women, diabetics and hypertensives was compared. As for the characteristics of acute myocardial infarction, an increase of patients in Killip class 3 and 4 stands out besides other changes. Fibrinolitic treatment decreased during the third period due to the increment in primary angioplasty. There were no significant differences in hospital mortality among the three series studied. The treatment with thrombolysis and primary angioplasty during the first two hours showed a significant independent reduction of mortality. CONCLUSIONS: The early application of thrombolysis and primary angioplasty showed an independent reduction of the hospital mortality in our study. Nevertheless the non-adjusted mortality rate did not show any change during the last 15 years.

[Transitory left deviation in the electrical axis of QRS during an exercise test as a manifestation of a severe proximal lesion of the descending anterior artery]. / Desviación izquierda transitoria del eje eléctrico del QRS durante la prueba de esfuerzo como manifestación de lesión severa proximal de la arteria descendente anterior.

The case of a patient in whom transient left axis deviation occurred during a treadmill exercise test is reported. Coronary angiography showed a 90% obstruction of the proximal left anterior descending artery. After a successful coronary angioplasty and stent implantation, a control exercise test was performed without a recurrence of angina or transient intraventricular conduction disturbance, reflecting the ischaemic nature of this abnormality.

N-acetyl-beta-D-hexosaminidase A from rat urine: partial purification and characterization.

N-Acetyl-beta-D-hexosaminidase A was purified from rat urine by ion-exchange chromatography on DEAE-cellulose, followed by concanavalin A chromatography, and finally by chromatography on 2-acetamido-N-(epsilon-aminocaproyl)-2-deoxy-beta-glucosylamine-Se pharose 4B. The enzyme was purified 482-fold with a yield of about 7%. The optimal pH was 4.5 for N-acetyl-glucosaminidase activity and 4.0-4.5 for N-acetylgalactosaminidase activity. The enzyme was heat-labile and stable from pH 4.5 to pH 7.0 but it was very unstable at lower pH values. Km values were 0.55 mM and 0.059 mM, respectively. The glycoprotein nature of the enzyme was deduced from its behavior on concanavalin A. The effect of some carbohydrates and ionic compounds on the activities of the enzyme was studied. When N-acetyl-D-glucosaminolactone and N-acetyl-D-galactosaminolactone were used as inhibitors, Ki values were also calculated.

Separation and characterization of four forms of beta-N-acetylhexosaminidase from chicken brain.

Chicken brain beta-N-acetylhexosaminidases from embryos (16 and 21 days old), newborns (1 and 4 days old), and adults (3 1/2 months and 2 years old) were separated into four different forms by ion exchange chromatography on diethylaminoethyl-cellulose. Three of these forms were "acid" hexosaminidases (I, IIA, and IIB), and the fourth was a "neutral" form. Throughout development of the chicken, forms IIA and III maintained the same activity ratio, whereas that for form I decreased and that for form IIB showed an increase.

Kinetic studies of four enzyme forms of beta-N-acetylhexosaminidase from embryonic chicken brain.

The separation of four different hexosaminidase forms from embryonic chicken brain (16-day-old) has been performed by ion-exchange chromatography. Two different DEAE-cellulose columns have been used: a first one at pH 7.2 and a second one at pH 6.0. Km and Vmax values were estimated from the Lineweaver-Burk or Dixon plots and ki from the Dixon plots, using N-acetyl-D-glucosamine or N-acetyl-D-galactosamine as inhibitors. In both cases we found a kind of competitive inhibition in which Lineweaver-Burk and Dixon plots curve downwards.