[Characterization of stroke patients attended at IMSS hospitals in Mexico City]. / Caracterización de los pacientes con EVC atendidos en hospitales del IMSS en la Ciudad de México.

BACKGROUND: Cerebrovascular disease (CD) is considered a problem of huge social, economic and public health implications worldwide in adults and elderly. In Mexico, the information concerning the provision of services to people and their characteristics is limited. The objective is to describe the characteristics of patients with CV who attended the hospitals of the Instituto Mexicano del Seguro Social (IMSS) in Mexico City. METHODS: It was carried out a cohort study of patients with ischemic or hemorrhagic CD who arrived to IMSS. Patients were recruited from seven IMSS general hospitals in Mexico City from June, 2013, to October, 2014. RESULTS: We assigned 430 subjects with CD (78.14% had ischemic CD). There were no statistical differences regarding gender. The median age of patients was 74 years. During their first 72 hours of hospital stay, it was assessed language proficiency in 90%, the ability to walk in 16.3% and the ability to move extremities in 94%. The main risk factors were hypertension, 84%; diabetes mellitus, 46.3%; history of CD, 25.1%; smoking history, 13.7%. 80% of patients reported that their health was regular or poor. CONCLUSIONS: General characteristics of patients and vascular risk factors are similar to those reported by other studies. Secondary prevention strategies are performed in less time than that recommended by international standards. It is urgent to design strategies to build better ways of care during the acute phase of patients with CD.

INTRODUCCIÓN: la enfermedad vascular cerebral (EVC) es un problema de grandes implicaciones a nivel mundial en población adulta y adultos mayores. Es limitada la información en México sobre la provisión de servicios a población con EVC y sus características. El objetivo es presentar las características de la población con EVC que acude a unidades hospitalarias del Instituto Mexicano del Seguro Social (IMSS) en la Ciudad de México. MÉTODOS: estudio de cohorte en pacientes con EVC isquémica o hemorrágica que llegaron a los servicios de urgencias de hospitales del IMSS. Los pacientes fueron reclutados de siete hospitales generales de zona en la Ciudad de México, de junio del 2013 a octubre del 2014. RESULTADOS: fueron 430 sujetos con EVC (78.14% presentó EVC isquémica). No hubo diferencias estadísticas entre hombres y mujeres. La mediana de edad fue 74 años. Durante las primeras 72 horas de su estancia hospitalaria, en 90% se evaluó la capacidad del lenguaje, en 16.3% la capacidad para caminar y en 94% la capacidad para mover las extremidades. Los factores de riesgo fueron hipertensión arterial (84%), diabetes mellitus (46.3%), antecedentes de EVC (25.1%), antecedentes de tabaquismo (13.7%). El 80% refirió que su salud era regular o mala. CONCLUSIONES: las características generales de los pacientes y los factores de riesgo vascular son similares a los reportados en otros estudios. Las estrategias de prevención secundaria se hacen en menos tiempo que el recomendado por los estándares internacionales. Es importante diseñar estrategias para mejorar la atención en la fase aguda de los pacientes con EVC.

[Key recommendations of the clinical guidelines of arterial hypertension in primary care]. / Recomendaciones de la guía de práctica clínica de hipertensión arterial en el primer nivel de atención.

BACKGROUND: Hypertension ranks first medical care in first level units. It is estimated that half of the patients with hypertension are uncontrolled. The purpose of this document is to provide recommendations to guide diagnosis and treatment of arterial hypertension in primary care, which have been considered key to the process of care, in order to help health professionals in the clinical decision-making. METHODS: The guide is integrated with recommendations of international guidelines and evidence of published studies indicated the changes regarding the management and treatment of hypertension, as well as differences between the target populations of the guide. Searching for information it is performed by means of a standardized sequence in PubMed and Cochrane Library Plus, from the questions asked. The key recommendations were chosen by a consensus of a group of professionals and health managers. CONCLUSIONS: The key recommendations evidence-based standardized help you make decisions about prevention, diagnosis and treatment in patients with hypertension, and will contribute to reducing cardiovascular risk, promote changes in lifestyle, control the disease and reduce complications.

Introducción: la hipertensión arterial (HA) ocupa el primer lugar de atención en unidades médicas de primer nivel. La mitad de los pacientes con HA no están controlados. El objetivo de este documento es proporcionar las recomendaciones de la guía de diagnóstico y tratamiento de HA en el primer nivel de atención que han sido consideradas clave para el proceso de atención, con el fin de ayudar a los profesionales de la salud, en la toma de decisiones clínicas. Métodos: la guía se integró con recomendaciones de guías internacionales y evidencias de estudios publicados que señalaron los cambios ocurridos en el abordaje y tratamiento de la HA, así como las diferencias entre los grupos poblacionales blanco de la guía. La búsqueda de información se realizó por medio de una secuencia estandarizada en Pubmed y Cochrane Library Plus. Las recomendaciones clave se eligieron por consenso de un grupo de profesionales y gestores de la salud. Conclusiones: las recomendaciones clave, basadas en evidencias, ayudarán a tomar decisiones estandarizadas sobre prevención, diagnóstico y tratamiento en pacientes con HA, y coadyuvarán a disminuir el riesgo cardiovascular, impulsar cambios en el estilo de vida, controlar la enfermedad y reducir las complicaciones.

[Methodology for the development and update of practice guidelines: current state]. / Metodología para el desarrollo y la actualización de guías de práctica clínica: estado actual.

The current scenario of health services in Mexico reveals as a priority the implementation of strategies that allow us to better respond to the needs and expectations of individuals and society as a whole, through the provision of efficient and effective alternatives for the prevention, diagnosis and treatment of diseases. In this context, clinical practice guidelines constitute an element of management in the health care system, whose objective is to establish a national bechmark for encouraging clinical and management decision making, based on recommendations from the best available evidence, in order to contribute to the quality and effectiveness of health care. The purpose of this document is to show the methodology used for the development and updating of clinical practice guidelines that the Instituto Mexicano del Seguro Social has developed in line with the sectorial model in order to serve the user of these guidelines.

El escenario actual de los servicios de salud en México revela como una prioridad implementar estrategias que nos permitan dar una mejor respuesta a las necesidades y expectativas de los individuos y de la sociedad en su conjunto, a través de la oferta de alternativas eficientes y efectivas para la prevención, el diagnóstico y el tratamiento de las enfermedades. En este contexto, las guías de práctica clínica (GPC) constituyen un elemento de rectoría en la atención médica, cuyo objetivo es establecer un referente nacional para favorecer la toma de decisiones clínicas y gerenciales, basadas en recomendaciones sustentadas en la mejor evidencia disponible, a fin de contribuir a la calidad y la efectividad de la atención médica. El propósito de este documento es mostrar la metodología utilizada para el desarrollo y la actualización de las GPC que ha elaborado el Instituto Mexicano del Seguro Social (IMSS), metodología alineada con el modelo sectorial para que sirva al usuario de las guías como punto de partida para su comprensión y para que apoye su utilización.

[Experience of the Mexican National Health System in the development of clinical practice guidelines]. / Experiencia del Sistema Nacional de Salud Mexicano en el desarrollo de guías de práctica clínica.

BACKGROUND: Clinical practice guidelines are tools that have been able to streamline decisions made in health issues and to decrease the gap between clinical action and scientific evidence. OBJECTIVE: The objective of the study is to share the experience in the development and to update the guidelines by the National Health System of Mexico. MATERIAL AND METHODS: The methodology in the development of the guidelines consists of 5 phases: prioritisation, establishment of work groups, development by adoption of international guidelines of de novo, validation and integration in the Master catalogue of clinical practice guidelines for its dissemination. RESULTS: The Master catalogue of clinical practice guidelines contains 664 guidelines, distributed in 42% Internal Medicine, 22% Surgery, 24% Pediatrics and 12% Gynecology. From the total of guidelines coverage is granted at an 85% of the Universal catalogue of health services, an 84% of the Catastrophic expenses protection fund and a 61% of the XXI Century Medical Insurance of the National Commission of Social Protection in Health. DISCUSSION: The result is the sum of a great effort of coordination and cooperation between the institutions of the National Health System, political wills and a commitment of 3,477 health professionals that participate in guidelines' development and update. CONCLUSION: Master catalogue guidelines' integration, diffusion and implantation improve quality of attention and security of the users of the National Health System.

[General Strategies for Implementation of Clinical Practice Guidelines]. / Estrategias generales para la implementación de las Guías de Práctica Clínica.

The need to use clinical practice guidelines (CPG) arises from the health conditions and problems that public health institutions in the country face. CPG are informative documents that help improve the quality of care processes and patient safety; having among its objectives, to reduce the variability of medical practice. The Instituto Mexicano del Seguro Social designed a strategic plan for the dissemination, implementation, monitoring and control of CPG to establish an applicable model in the medical units in the three levels of care at the Instituto. This paper summarizes some of the strategies of the plan that were made with the knowledge and experience of clinicians and managers, with which they intend to promote the adoption of the key recommendations of the guidelines, to promote a sense of belonging for health personnel, and to encourage changes in organizational culture.

La necesidad de utilizar las guías de práctica clínica (GPC) surge de las condiciones y problemáticas de salud a las que se enfrentan las instituciones públicas de salud del país. Las GPC constituyen documentos informativos que contribuyen a mejorar la calidad de los procesos de atención y la seguridad del paciente; teniendo entre sus objetivos, reducir la variabilidad de la práctica médica. El Instituto Mexicano del Seguro Social diseñó un plan estratégico para la difusión, implementación, monitorización y control de GPC, a fin de instituir un modelo aplicable en las unidades médicas en los tres niveles de atención del Instituto. En este documento se resumen algunas de las estrategias del plan que fueron elaboradas con el conocimiento y experiencia de clínicos y gestores, con las que, se pretende impulsar la adopción de las recomendaciones clave de las guías y promover el sentido de pertenencia del personal de la salud, así como favorecer cambios en la cultura organizacional.

[Clinical practice guideline on closed tibial plateau fractures in adulthood]. / Guía de práctica clínica. Fractura cerrada de la meseta tibial en el adulto.

Closed tibiae plateau fractures are common injuries in the emergency room. The optimal treatment is not well defined or established. For this reason, there are several surgical management options: open reduction and internal fixation, closed reduction and percutaneous synthesis, external fixation, and even conservative treatment for this kind of fracture. The mechanism of production of this fracture is through large varus or valgus deformation to which is added a factor of axial load. The trauma may be direct or indirect. The degree of displacement, fragmentation and involvement of soft tissues like ligaments, menisci, vascular and nerve structures are determined by the magnitude of the force exerted. Any intra-articular fracture treatment can lead to an erroneous instability, deformity and limitation of motion with subsequent arthritic changes, leading to joint incongruity, limiting activity and significantly altering the quality of life. Open reduction and internal fixation with anatomic restitution is the method used in this type of fracture. However, the results of numerous publications can be questioned due to the inclusion in the same study of fractures treated with very different methods.

Las fracturas de la meseta tibial cerradas son lesiones frecuentes en los servicios de urgencias, cuyo tratamiento óptimo no se encuentra bien definido, ya que existen para un mismo tipo de fractura diversas opciones de manejo quirúrgico, como reducción abierta y fijación interna, reducción cerrada con síntesis percutánea, fijación externa e incluso tratamiento conservador. El mecanismo de producción de estas fracturas es a través de grandes deformaciones en varo o valgo a las que se añade un componente de carga axial. El traumatismo puede ser directo o indirecto. El grado de desplazamiento, la fragmentación y la afectación de partes blandas (ligamentos, meniscos, estructuras vasculares y nerviosas) se encuentran determinados por la magnitud de la fuerza ejercida. Como en cualquier fractura intraarticular, un tratamiento erróneo puede dar lugar a inestabilidad, deformidad y limitación de la movilidad, con los consiguientes cambios artrósicos, lo cual provocará incongruencia articular, limitará la actividad y alternará de forma significativa la calidad de vida. La reducción abierta y la fijación interna con la que se busca la restitución anatómica es un método utilizado en este tipo de fracturas. Sin embargo, los resultados de numerosas publicaciones pueden ser cuestionados debido a la inclusión en un mismo estudio de fracturas tratadas con métodos muy diferentes.

[Clinical practice guideline. Traumatic urethral stenosis in males]. / Guía de práctica clínica. La estenosis de uretra postraumática en el hombre.

The incidence of urethral stenosis in Mexico had not been documented. At the Centro Médico Nacional La Raza, during the year 2010, 629 patients with urethral stenosis were attended as outpatient consultation: 85 % with previous urethral stenosis and 15 % with urethral treatment complication. Urethral stenosis is a chronic illness, with multiple etiological origins and the handling is controversial. It has a great negative impact for the patients and the recurrence reaches 85 %. The treatment consisted of an invasive approach (urethral dilations, endoscopy procedure) and open surgery (urethroplasty). The World Health Organization and World Alliance take the world challenge about the urinary tract infections associated with the attention of patients, focused on urethral stenosis. The objective of the following clinical guide is to offer to the health professional a clinical tool for making decisions in the handling of the hardship or masculine urethral stenosis, based on the best available evidence, carrying out in systematized form with bibliographical research using validated terms of the MeSH: urethral structures, in the databases Trip database, PubMed, Guideline Clearinghouse, Cochrane Library and Ovid.

En México no está documentada la incidencia de la estenosis de uretra en forma consistente. En 2010, en el Centro Médico Nacional La Raza se reportaron 629 pacientes en consulta externa, 85 % de uretra anterior y 15 % de uretra posterior. La estenosis uretral es una enfermedad crónica, de etiología variada y manejo controvertido, con gran impacto negativo para los pacientes y recurrencia hasta de 85 %. El tratamiento puede ser instrumentado (dilataciones, cirugía endoscópica) y por cirugía abierta (uretroplastia). La Organización Mundial de la Salud y Alianza Mundial la consideran un reto de la atención de la salud. El objetivo de la siguiente guía es ofrecer al profesional de la salud, una herramienta clínica para la toma de decisiones en la atención de la estenosis uretral masculina, basada en la mejor evidencia identificada mediante la búsqueda bibliográfica sistematizada en las bases de datos Tripdatabase, PubMed, Guideline Clearinghouse, Cochrane Library y Ovid.

Modifying cancer patients' attitudes towards medical care received in the oncology service.

BACKGROUND: Attitude changing involves a holistic change on individual biopsychosocial structure. That attitude is understood by behaviors, thoughts, feelings and higher mental processes involved with behavior. This attitude will be considered in two ways: favorable or unfavorable, through a part of the environment. If unfavorable, the most common way to change it is through teaching and learning processes. The aim of this study was to evaluate the impact of a program directed to modify cancer patients' attitudes. METHODS: This study was performed in three stages from February to September 2009 in the Medical Oncology Area of the UMAE Oncology Hospital, Instituto Mexicano del Seguro Social (IMSS), according to a before and after quasi-experimental design to evaluate the effect of the intervention. The first stage was to diagnose through semantic networks using the results to create and validate a survey. The second stage was the educative intervention focused on providing general information to patients in the area of medical oncology. Finally, the initial survey was used in order to measure the impact of the intervention, which had been previously implemented and validated. The cumulative total of patients during the three stages was 4,200. RESULTS: Patients attitudes were modified with a specific favorable tendency on the instrument from 51% to 94% (p = 0.05) of total instrument perceptions. CONCLUSIONS: This intervention significantly changed patients' attitudes related to the medical oncology area.

Survey on physicians' knowledge and attitudes towards clinical practice guidelines at the Mexican Institute of Social Security.

OBJECTIVE: A survey was organized to determine the general level of knowledge and attitudes of medical personnel towards clinical practice guidelines (CPG). METHODS: A questionnaire modified from two validated instruments was used. Multi-stratified sampling was applied, and 1782 questionnaires were completed. RESULTS: A total of 80.4% of physicians had regular employment contract, 8.6% managerial post and 9.3% temporary work contract. Average age and working time were 43.7 and 15 years respectively; 64.3% were male. It was reported that 47.9% participated in academic activities, 70.8% belonged to a medical association, 40.3% identified CPG as steps towards arriving at a diagnosis and/or treatment and 14.9% thought that CPG were norms. A total of 10.7% of the physicians believed that guidelines are based on scientific evidence, 10% perceived them as supporting tools, 10.8% had no knowledge of them, 65% said that they used them, 76.7% thought that personal experience was as important as CPG recommendations and 57.4% thought that CPG were necessary for good medical practice. Physicians preferred that CPG be produced by personnel from outside the Mexican Institute of Social Security, or who had followed validity criteria. CONCLUSIONS: The majority of physicians considered CPG to be useful tools. It was evident that few knew where to acquire CPG, and this would lead to their limited use. Findings from this study enabled procuring a broader idea of the level of knowledge and attitudes of Mexican Institute of Social Security physicians towards CPG. This information is relevant when planning strategies for the purpose of sharing and implementing CPG.

[A clinical guideline for diagnosis and treatment of hydrocele in childhood]. / Guía de práctica clínica. Diagnóstico y tratamiento del hidrocele en los niños.

OBJECTIVE: To develop a guideline available to the medical staff of the first and second level of care, which includes recommendations based on the best available evidence about diagnosis and management of hydrocele in the pediatric patient. METHODS: Clinical questions were formulated and structured. Standardized sequence was established to search for practice guidelines from the clinical questions raised on diagnosis and treatment of hydrocele in children. The working group searched clinical practice guidelines and found only one. For recommendations not included in the reference guide the search process was conducted in PubMed and Cochrane Library. The results were expressed as levels of evidence and grade of recommendation. CONCLUSIONS: The most of the infant hydroceles are communicating and do resolve without treatment, however recognize those to need surgery is necessary to treat opportunely.

[The clinical guidelines of practice project at the Instituto Mexicano del Seguro Social]. / Proyecto para el desarrollo de guías de práctica clínica en el Instituto Mexicano del Seguro Social.

The advance in the knowledge and technology is growing quickly and greater quantity, so it is difficult for the health professional to access to whole information that is generated every day on diagnostic and therapeutic strategies more effective, so the clinic practice guidelines (CPG) is a resource to support the updating of the health professional and support them in making clinical decisions. The CPG is also a better support to the manager of health services in making decisions regarding the strategies that have performed for the patient and less risk to the individual and collective health. They also support the response capacity of the medical units and hospitals and guide the planning of services to the optimization of the resources. This paper summarizes the methodology of a national project for the development of GPC coordinated by the Mexican Social Security Institute with the collaboration of more than 1200 health professionals of the institution in a great effort institutional update and make information accessible to the entire health sector, which also defines the steps to upgrade and maintain the updating of knowledge and technology expressed in them.

[The clinical guidelines as a potential tool to improving health care quality]. / El potencial de las guías de práctica clínica para mejorar la calidad de la atención.

There is an increasing demand to ensure quality in the providing and receiving health care. Health care services face different challenges, such as: a growing aging population, increasing care costs, variations in clinical practice, and a fasting increase in the generation of information on diagnostic methods and therapies. In this context, a wave of development and use of clinical guidelines (CGL) based on scientific evidence has emerged worldwide, with the aim to creating tools to promote clinical excellence in practice. Our country and the Instituto Mexicano del Seguro Social (IMSS), with its experience in developing CGL has joined this trend as a main project. It is beneficial for IMSS health professionals and their patients. The aim of this paper is to present general information on definitions, structure, quality standards, development proceedings, updating, and potential advantages and disadvantages by using CGL. To achieve the expectations of a positive impact on quality and the health care budget distribution, health care personnel must be open to and receptive to the CGL recommendations and be flexible in changing their clinical practice.

[Lymphatic mapping and sentinel lymph node biopsy in patients with high risk squamous cell carcinoma of the skin]. / Mapeo linfático y biopsia del ganglio centinela en pacientes con carcinoma epidermoide cutáneo de alto riesgo.

BACKGROUND: Some sub-groups of cutaneous squamous cell carcinoma (CSCC) display a higher risk for regional metastasis. Sentinel lymph node staging has been used successfully to evaluate nodal metastasis in selective tumors. OBJECTIVE: Assess the feasibility of sentinel node to detect occult regional lymph node metastasis in high-risk CSCC. MATERIAL AND METHODS: Between January 2002 and March 2004, a total of 20 patients received pre-operative lymphoscintigraphy and sentinel lymphadenectomy for high-risk CSCC with clinically non-palpable regional lymph nodes. RESULTS: In one of each 5 patients (20%), sentinel lymph node showed histological evidence of microinvolvement. No patients with negative sentinel node showed tumor dissemination during follow-up, with a mean of 23.5 months (range 7-44). CONCLUSIONS: Sentinel lymph node biopsy is technically feasible with low morbidity. Sentinel lymphadenectomy may play an important role in the management of high-risk CSCC with clinically non-palpable regional lymph nodes. This technique can help identify patients with regional lymph node metastases who may benefit from complete lymphadenectomy. This improved staging may allow clinicians to better stratify patients who might benefit from adjuvant therapy.

Mapeo linfático y biopsia del ganglio centinela en pacientes con carcinoma epidermoide cutáneo de alto riesgo / Lymphatic mapping and sentinel lymph node biopsy in patients with high risk squamous cell carcinoma of the skin

Introducción: Un subgrupo de pacientes con carcinoma epidermoide cutáneo (CEC) tiene alto riesgo de presentar metástasis ganglionares regionales. El mapeo linfático y biopsia del ganglio centinela (MLBGC) ha sido exitosamente utilizado para evaluar la presencia de metástasis ganglionares subclínicas en diversos tumores. bjetivo: Evaluar la utilidad de la técnica del MLBGC en los pacientes con CEC de alto riesgo para detectar la presencia de metástasis ganglionares regionales subclínicas. Material y métodos: De enero 2002 a marzo 2004, un total de 20 pacientes con CEC de alto riesgo con ganglios linfáticos regionales clínicamente no palpables fue evaluado con linfografía preoperatoria y MLBGC. Resultados: En 1 de cada 5 pacientes (20 %), el ganglio centinela reveló la presencia de micrometástasis. Ningún paciente con GC negativo manifestó progresión tumoral ganglionar regional durante un seguimiento medio de 23.5 meses (rango de 7 a 44 meses). Conclusiones: El MLBGC fue técnicamente posible con baja morbilidad. El MLBGC puede tener un importante papel en el tratamiento de los pacientes con CEC de alto riesgo con ganglios linfáticos regionales no palpables. Esta técnica puede ayudar a identificar los pacientes con metástasis en los ganglios linfáticos regionales que pueden beneficiarse de una disección ganglionar radical. Además provee importante información para utilizar terapias adyuvantes a la cirugía.

BACKGROUND: Some sub-groups of cutaneous squamous cell carcinoma (CSCC) display a higher risk for regional metastasis. Sentinel lymph node staging has been used successfully to evaluate nodal metastasis in selective tumors. OBJECTIVE: Assess the feasibility of sentinel node to detect occult regional lymph node metastasis in high-risk CSCC. MATERIAL AND METHODS: Between January 2002 and March 2004, a total of 20 patients received pre-operative lymphoscintigraphy and sentinel lymphadenectomy for high-risk CSCC with clinically non-palpable regional lymph nodes. RESULTS: In one of each 5 patients (20%), sentinel lymph node showed histological evidence of microinvolvement. No patients with negative sentinel node showed tumor dissemination during follow-up, with a mean of 23.5 months (range 7-44). CONCLUSIONS: Sentinel lymph node biopsy is technically feasible with low morbidity. Sentinel lymphadenectomy may play an important role in the management of high-risk CSCC with clinically non-palpable regional lymph nodes. This technique can help identify patients with regional lymph node metastases who may benefit from complete lymphadenectomy. This improved staging may allow clinicians to better stratify patients who might benefit from adjuvant therapy.

[Cost-effectiveness analysis of nuclear cardiology and its impact on total expense for diagnosis of coronary artery disease]. / Costo-efectividad de los estudios de gamagrafía miocárdica e impacto al gasto total por diagnóstico de cardiopatía isquémica.

BACKGROUND: Medical care in a hospital under a socialized medicine system should be highly effective at the lowest expense possible. When myocardial perfusion studies are performed in well-selected patients, the costs decrease because of the need for fewer invasive studies. When patients are not selected properly, there is an increase-wasted resource, making it necessary to perform cost-effective studies. The goal of this study is to evaluate the economical impact of the diagnostic process in patients suspected of having coronary artery disease, referred to our service (Nuclear Medicine, Hospital de Cardiología CMN, IMSS) in 2002. METHODS: We analyzed 1966 reports of myocardial gammagrams. Patient reports were stratified according to their referring unit. The sum of the unitary fixed cost was converted to the unitary cost for each reason for referral. Kappa was used to evaluate concordance. RESULTS: Patients were 62 +/- 11.39 years old, 52% male. Concordance between the referring diagnosis and the myocardial gammagram was <1% (p <0.001). The cost of cardiac gammagrams varied between $2,613.11 and $3,306.77 (Mexican pesos). Waste was calculated at 30%, which represented $1.8 million (Mexican pesos). CONCLUSIONS: Cost-effective studies are important tools in the administration of resources. In this particular case the results indicate the necessity for systematic registration of financial information, periodic review of operation costs by service, and criteria for use of high-cost services.

[Physiopathological alterations secondary to extracorporeal circulation in cardiac surgery]. / Alteraciones fisiopatólogicas secundarias a circulación extracorpórea en cirugía cardíaca.

Cardiopulmonary bypass (CPB) is one of the methods used in myocardial revascularization and can be associated with adverse events that are uncommon, but CPB induces high morbidity and mortality. Cardiac surgery and CPB activate a systemic inflammatory response characterized by tissular lesions, cells movements and blood flow toward the interstice where the harmful stimulus has begun, under the influence of the mediators. The systemic inflammatory response may be initiated during cardiac surgery by a number of processes, including blood contact with the foreign surface of the CPB apparatus, development of ischemia and reperfusion injury, and presence of endotoxemia. In the course of cardiac surgery using CPB, all three processes are present and contribute concurrently to the systemic inflammatory response. The term "systemic inflammatory response syndrome" (SIRS) has been proposed to describe an entity that continually overlaps with normal postoperative physiology. A frequent complication of SIRS is the development of organ dysfunction, including acute lung injury, shock, renal failure, and multiple organ dysfunction syndrome. Finally, long-term survival in patients developing SIRS may also be adversely affected. The purpose of this review is to examine and understand the pathological mechanisms for inflammatory response that occur following cardiopulmonary bypass.

[Left atrial dissection. Review]. / Disección de aurícula izquierda. Revisión de la literatura.

The left atrial dissection is a rare complication occurring mainly after mitral surgery, thoracic trauma, myocardial infarction and infectious endocarditis. The clinical diagnosis can be confused with isolated prosthetic dysfunction, myocardial infarction. Its onset and, its form of presentation vary widely, concerning to the intensity and to the moment in which the symptoms appear. The most important data for its diagnostic are the antecedents and a new systolic murmur, although this last one can be absent. The transesophageal echocardiogram is the first choice for diagnosis since, the dissection can be missed by transthoracic echocardiogram. The treatment is surgical, two different types of surgical approaches have been reported. The prognosis depends on the extension of the dissection, tissue quality and associated complications.

[Mitral valve prolapse. A review]. / Prolapso valvular mitral. Revisión de la literatura.

Primary mitral valve prolapse (MVP) or the disease known as MVP, consists of mixomatous degeneration of the mitral valve with systolic displacement of a portion or all of one or both mitral leaflets beyond mitral annulus into left atrium during systole, associated or not with mitral insufficiency. Prevalence in Mexican population is <2%. MVP behavior is benign unless associated with mitral insufficiency (MI, moderate-to-severe) or complications, or is associated with other syndromes. The major clinical feature of mitral valve prolapse syndrome is mid-to-late systolic clicks identified with auscultation of mitral valve. Echocardiography is usually employed for diagnosis and management. Two-dimensional echocardiography displays one or both leaflets prolapsing behind mitral annulus and into left atrium in systole. In the majority of cases, MVP is harmless and does not cause symptoms nor does it need to be treated. In a small number of cases, it can cause severe mitral regurgitation and needs surgical treatment. Complications derived from MVP must be treated independently. Secondary MVP also consist of displacement of one or both valves toward atrium, but this is due to pathologies such as rheumatic heart disease, ischemic heart disease, or others. In these situations, treatment will be that of the underlying diseases.

[Nosocomial infection surveillance: experience at a cardiology hospital in Mexico]. / Vigilancia de infecciones nosocomiales: experiencia de un hospital de cardiología en México.

OBJECTIVE: To describe the results of the Nosocomial Infection surveillance program at the Cardiology Hospital in Centro Médico Nacional Siglo XXI of the Mexican Social Security Institute. METHODOLOGY: To inform of the epidemiologic follow-up results from January 2000 to July 2003. Global frequency, infection rates by infection site, hospital services, and frequency of most common microorganisms were estimated. RESULTS: During this period, global incidence showed that in every 100 discharges, there were 4.3 infections (4.3/100). Frequency of infection was slightly higher in the surgical intensive care unit. Average infection rate in lower respiratory tract infections was 27/1,000; in surgical-site infections: 8/1,000 (mediastinitis 0.8/1,000); it was found that in urinary tract infection, rate was 6.6/1,000. Most commonly isolated microorganisms were: coagulase-negative Staphylococcus (25%), Enterobacter sp. (17%), Candida albicans (13%), S. aureus (9%), P. aeruginosa (9%) and K. pneumoniae (6%). CONCLUSION: This study describes the epidemiology of nosocomial infections in a Cardiology Hospital. The information is obtained through epidemiologic follow-up programs. This information is very important to develop specific strategies for control of infections.

Concordancia en la interpretación de radiografías de tórax, en niños / Agreement in the interpretration of thorax X-rays, in children

Con la finalidad de evaluar la concordancia de los pediatras en la interpretación de placas de tórax de niños, se realizó un estudio de corte transversal. Se estudiaron 50 radiografías técnicamente edecuadas y seleccionadas al azar, en las que se observaron las diferentes estructuras torácicas; participaron seis pediatras, 11 residentes de pediatría y dos radiólogos pediatras. El coeficiente Kappa, de concordancia para los radiólogos fue de 52.4 por ciento (moderado y clínicamente adecuado), en los pediatras fue de 21.5 por ciento (bajo y clínicamente deficiente). La concordancia entre los pediatras y los radiólogos fue de 17 por ciento y entre los radiólogos y los residentes de 14.0 por ciento; la exactitud también fue deficiente. Es necesario revisar los criterios radiológicos e implementar estrategias para superar las deficiencias identificadas