Dopamina no previene insuficiencia renal aguda

Hace ya un tiempo (2001) en Critical Care Medicine se publicó un meta-análisis que mostró que la dopamina en bajas dosis (5µg/kg/min) no reduce la incidencia de insuficiencia renal aguda. Cabe recordar que las recomendaciones 2000 para reanimación cardiopulmonar y atención cardiovascular de urgencia de la American Heart Association no recomiendan el uso de dopamina para este efecto.

Use of dopamine in acute renal failure: A meta-analysis.
Clinical Investigations Critical Care Medicine. 29(8):1526-1531, August 2001.Kellum, John A. MD; M. Decker, Janine RN

Abstract
Objective: To determine whether low-dose dopamine administration reduces the incidence or severity of acute renal failure, need for dialysis, or mortality in patients with critical illness.
Data Sources and Study Selection : We performed a MEDLINE search of literature published from 1966 to 2000 for studies addressing the use of dopamine in the prevention and/or treatment of renal dysfunction.
Data Extraction : Data were abstracted regarding design characteristics, population, intervention, and outcomes. Results of individual randomized clinical trials were pooled using a fixed effects model and a Mantel-Haenszel weighted chi-square analysis.
Data Synthesis: We identified a total of 58 studies (n = 2149). Of these, outcome data were reported in 24 studies (n = 1019) and 17 of these were randomized clinical trials (n = 854). Dopamine did not prevent mortality, (relative risk, 0.90 [0.44-1.83];p = .92), onset of acute renal failure (relative risk, 0.81 [0.55-1.19];p = .34), or need for dialysis, (relative risk, 0.83 [0.55-1.24];p = .42). There was sufficient statistical power to exclude any large (>50%) effect of dopamine on the risk of acute renal failure or need for dialysis.

Conclusions: The use of low-dose dopamine for the treatment or prevention of acute renal failure cannot be justified on the basis of available evidence and should be eliminated from routine clinical use.

Analfabetismo: Un factor poco considerado en medicina

Un paciente no entiende a cabalidad la información y recomendaciones que le realizamos, ¿no será el motivo que el paciente no sabe leer ni escribir?. Consideremos que como aparece en el articulo que les recomendare en EEUU un 12% de los adultos no son capaces de comprender lo que aparece en una etiqueta. ¿Nos preocupamos de conocer el grado de entendimiento de nuestros pacientes?. Un interesante articulo en el New England Journal of Medicine trata este tema.

El link para el PDF en inglés es: http://content.nejm.org/cgi/reprint/355/4/339.pdf

Novedades en Antibióticos

Una descripción de antibióticos disponibles en nuestro país a partir del año 2000. Trabajo publicado en 2005 en la Revista Chilena de Urología donde se describen tres antibióticos de tres familias distintas: 1) Linezolid (Oxazolidinonas); 2) Moxifloxacino (Quinolonas); 3) Ertapenem (Carbapenems).

Formato PDF. En español.

http://www.urologosdechile.cl/pdf.php?id=227

Significado Predictivo de Ascitis en TAC Preoperatorio en Cáncer Gástrico

Les presento el abstract de un trabajo retrospectivo realizado por investigadores japoneses investigando el valor predictivo de la presencia de ascitis en pacientes con cáncer gástrico respecto de la presencia de metastásis peritoneales. Los resultados de este trabajo muestran una correlación significativa con siembra peritoneal tanto en análisis univariado como multivariado.
Los autores recomiendan que en casos de pacientes con cáncer gástrico en quienes la tomografía axial computada muestre ascitis se proponga hacer una laparoscopia diagnóstica.

Clinical and diagnostic significance of preoperative computed tomography findings of ascites in patients with advanced gastric cancer
Kazuhito Yajima M.D.a, Tatsuo Kanda M.D., Ph.D.a, , , Manabu Ohashi M.D.a, Toshifumi Wakai M.D.a, Satoru Nakagawa M.D.a, Ryuta Sasamoto M.D.b and Katsuyoshi Hatakeyama M.D., Ph.D., F.A.C.S.b
aDivision of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Niigata 951-8510, JapanbDivision of Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan Received 6 April 2005; revised 21 January 2006.

Background
The relationship between ascites, as detected by preoperative computed tomography (CT), and peritoneal metastasis of gastric cancer requires clarification because of its likely significance for clinical outcome.
Methods
A retrospective analysis of 293 patients with advanced gastric cancer investigated the association between preoperative CT findings of ascites and surgical findings of peritoneal washing cytology and peritoneal metastasis.
Results
Forty-five of 293 patients (15%) presented with ascites on preoperative CT. Positive ascites on CT predicted the presence of free tumor cells with 40% sensitivity and 97% specificity, and peritoneal metastasis with 51% sensitivity and 97% specificity. Ascites on CT was an independent prognostic factor by univariate (P < .001) and multivariate (relative risk, 2.03; 95% confidence interval, 1.39–2.96; P < .001) analyses. The median survival time was 6.0 months in patients with positive ascites on CT.
Conclusions
The presence of ascites on CT suggests the presence of peritoneal metastasis and indicates a poor prognosis. The presence of peritoneal metastasis should be confirmed by diagnostic laparoscopy in gastric cancer patients with ascites.

Hernia Inguinal Asintomática ¿Operar u Observar?

En la edición de agosto de Annals of Surgery aparece un estudio randomizado comparando manejo quirúrgico vs observación de hernias inguinales asintomáticas. La población estudiada correspondió a hombres mayores de 55 años. Los "outcomes" principales fueron dolor y estado de salud a 6 meses y un año. Fueron evaluados también los costos y tasas de reoperación.

A continuación el abstract:

Observation or Operation for Patients With an Asymptomatic Inguinal Hernia: A Randomized Clinical Trial.
Annals of Surgery. 244(2):167-173, August 2006.
O'Dwyer, Patrick J. FRCS +; Norrie, John MSc *; Alani, Ahmed FRCS ++; Walker, Andrew PhD *; Duffy, Felix RN [S]; Horgan, Paul FRCS *

Objective: Many patients with an inguinal hernia are asymptomatic or have little in the way of symptoms from their hernia. Repair is often associated with long-term chronic pain and has a recurrence rate of 5% to 10%. Our aim was to compare operation with a wait-and-see policy in patients with an asymptomatic hernia.
Methods: A total of 160 male patients 55 years or older were randomly assigned to observation or operation. Patients were assessed clinically and sent questionnaires at 6 months and 1 year. The primary endpoint was pain and general health status at 12 months; other outcome measures included costs to the health service and the rate of operation for a new symptom or complication.
Results: At 12 months, there were no significant differences between the randomized groups of observation or operation, in visual analogue pain scores at rest, 3.7 mm versus 5.2 mm (mean difference, -1.6; 95% confidence interval (CI), -4.8 to 1.6, P = 0.34), or on moving, 7.6 mm versus 5.7 mm (mean difference, -1.9; 95% CI, -6.1 to 2.4, P = 0.39). Also, the number of patients 29 versus 24 (difference in proportion, 8%; 95% CI, -7% to 23%, P = 0.31), who recorded pain on moving and the number taking regular analgesia, 9 versus 17 (difference in proportion, -10%; 95% CI, -21% to 2%, P = 0.14) was similar. At 6 months, there were significant improvements in most of the dimensions of the SF-36 for the operation group, while at 12 months although the trend remained the same the differences were only significant for change in health (mean difference, 7.3; 95% CI, 0.4 to 14.3, P = 0.039). The rate of crossover from observation to operation 23 patients at a median follow-up of 574 days was higher than predicted. The observation group also suffered 3 serious hernia-related adverse events compared with none in the operation group.

Conclusions: Repair of an asymptomatic inguinal hernia does not affect the rate of long-term chronic pain and may be beneficial to patients in improving overall health and reducing potentially serious morbidity.

Necrosis Intestinal Asociado con Yeyunostomia

Un artículo publicado en el Archives of Surgery realiza una revisión de una complicación de las yeyunostomías que de no tener un alto grado de sospecha puede causar sepsis, falla multiorgánica y muerte. A continuación el abstract

Bowel Necrosis Associated With Early Jejunal Tube Feeding
A Complication of Postoperative Enteral Nutrition
Marcovalerio Melis, MD; Alessandro Fichera, MD; Mark K. Ferguson, MD
Arch Surg. 2006;141:701-704.
Hypothesis Postoperative enteral nutrition may sometimes be responsible for severe complications such as mesenteri ischemia.
Data Sources Studies in the English literature were identified by a computer-assisted search of the MEDLINE database using the key words "enteral feeding OR jejunostomy" AND "complications OR mesenteric ischemia." Cited references of each retrieved paper were checked for relevance.
Study Selection All reports of mesenteric ischemia in the setting of postoperative enteral feeding were included. In cases of multiple articles from the same institution with overlapping patients, the most exhaustive article was included.
Data Extraction All reports were abstracted for number of patients, presence of preoperative comorbidities, development of perioperative hypotension or mesenteric occlusion, and outcome.
Data Synthesis Nine studies were retrieved in which enteral feedings were responsible for bowel ischemia; we report an additional case. The common clinical picture is that of a patient without significant risk factors for mesenteric ischemia, which during the early postoperative course develops nonspecific abdominal symptoms and then rapidly progresses to septic shock and eventually to multisystem organ failure and death. Mesenteric ischemia may present in up to 3.5% of enterally fed surgical patients; the associated mortality approaches 100%. The lack of specific symptoms requires a high index of suspicion for diagnosis; prompt abdominal exploration and bowel resection are the only chance for survival.
Conclusions The benefits of enteral nutrition outweigh the likelihood of severe complications; when mesenteric ischemia develops, early diagnosis is challenging and the prognosis is poor.
Author Affiliations: Department of Surgery, University of Chicago, Chicago, Ill.

Cirugía hoy en día: una opinión

Tras asistir a la reunión de la Sociedad de Cirujanos de Chile que trataba el tema "Rol de la Sociedad de Cirujanos de Chile en la formación quirúrgica nacional", no puedo dejar de realizar algunos comentarios.

De partida es bueno saber que muchos cirujanos estan de acuerdo en los "debieran"... Debiera uniformarse los requerimientos para ser cirujano. Debiera certificar y recertificar la profesión. Debiera pagarse a los becados por su labor asistencial, etc.

Sin embargo, me llamó profundamente la atención que no se conoce el número exacto de cirujanos (y de médicos tampoco) actualmente en ejercicio y se hace inferencias según datos aportados por CONACEM (Cuya certificación no es obligatoria para los especialista formados por universidades de ASOFAMECH) y de los socios de la SChC (no todos los cirujanos son socios) y dichas estimaciones van desde alrededor de 800 cirujanos a 1200.

Si no conocemos el número exacto de especialistas y de aquellos que se "dedican" a la cirugía sin ser cirujanos ¿como poder saber las medidas necesarias a instaurar para satisfacer los requerimientos actuales y futuros del país en el área quirúrgica?

Cáncer de vesícula biliar en Chile. Un estudio epidemiológico

El cáncer de vesícula biliar, primera causa de muerte oncológica de mujeres en Chile (y por esa razón su prevención es GES). Un estudio epidemiológico entre los años 1985 y 2002 fue recién publicado en la Revista Médica de Chile (Rev Med Chile 2006; 134:565-74) . Se muestra que las regiones IX y X tienen la mayor cantidad de afectadas por esta neoplasia. Les proporcionó el link al trabajo completo (el que es gratis) desarrollado por los Drs. Marcelo Andia, Alessandra Gederlini y CatterinaFerreccio.

http://contacto.med.puc.cl/destacados/tumores/estudio%20UC%20cancer%20ves’cula.pdf

Cirugía de urgencia en cáncer de colón

Al hacer click en el título tendra acceso a una revisión publicada en el número de este mes de la Revista Española de Cirugía. Trata en forma bastante completa el enfrentamiento del cáncer de colón complicado: obstrucción y perforación.