Diseño e implementación de un modelo de enseñanza en ambiente simulado de paracentesis abdomina / Design and implementation of an environment teaching model simulated abdominal paracentesis

Resumen: El aprendizaje de los estudiantes de Medicina de Pregrado en ambiente simulado constituye una alternativa en la obtención de competencias técnicas y no técnicas. Objetivo: Desarrollar un fantoma e implementar un taller modular de entrenamiento de paracentesis abdominal en ambiente simulado para estudiantes de Medicina. Métodos: Se diseñaron y desarrollaron modelos para la realización de paracentesis abdominal en la Escuela de Diseño de la Pontificia Universidad Católica de Chile (PUC) y se implementó un taller para alumnos de 4to año de Medicina de la PUC, utilizando un enfoque constructivista, sesiones de entrenamiento simulado con debriefing basadas en el modelo plus-delta y evaluación pre y post-procedimiento siguiendo los principios de evaluación para el aprendizaje. Resultados: Se desarrollaron 3 prototipos hasta llegar a un modelo definitivo de alta fidelidad basado en la percepción de 20 expertos. 237 alumnos asistieron a un taller de paracentesis abdominal en el Centro de Cirugía Experimental y Simulación Universidad Católica (UC). Este consistió en una actividad práctica grupal (7-8 alumnos por sesión) que incluyó: una evaluación pre-sesión, un vídeo instruccional, una demostración en tiempo real en el fantoma por parte de un docente, la realización guiada del procedimiento por parte de los alumnos, debriefing y cierre de la sesión. Conclusiones: Un modelo de enseñanza en ambiente simulado es posible de ser diseñado e implementado exitosamente en un centro educacional para estudiantes de Medicina de Pregrado. Este taller de paracentesis permite entrenar a los alumnos en la realización de paracentesis abdominal en un ambiente seguro para los alumnos y pacientes y puede ser implementado a bajo costo en otros centros o instituciones. (AU)

Abstract: Simulated environments are an option in the learning process of undergraduate medical students in order to obtain technical and non-technical. Aim: To develop a mannequin for abdominal paracentesis and the implementation of a training workshop to perform abdominal paracentesis in a simulated environment for undergraduate medical students. Methods: The prototypes were designed and developed to perform abdominal paracentesis at the School of Design at the Pontificia Universidad Católica de Chile (PUC) and a workshop was implemented in a course with 4-year medical students at the PUC, using a constructivist approach and simulated training sessions and providing debriefing (based on plus-delta model) and pre-post training assessment following the principles of Assessment for Learning. Results: Three prototypes were developed until the final high-fidelity-mannequin was achieved. The abdominal paracentesis workshop was attended by 237 students at the Universidad Católica (UC) Experimental Surgery and Simulation Center. This was a hands-on group activity (7-8 students per session) including pre-session assessment, instructional video-tape, real-time demonstration of abdominal paracentesis procedure by the clinical teacher, followed by abdominal paracentesis performed by the students, debriefing and closing session. Conclusions: A teaching model in a simulated environment is feasible to be successfully designed and implemented in an educational center for undergraduate medical students. This workshop allows students training process to perform abdominal paracentesis in a safe environment for students and patients and it can be implemented in other centers or institutions with low cost.(AU)

Early-onset EBV-positive post-transplant plasmablastic lymphoma arising in a liver allograft: a case report and literature review.

We report a case of a 51-year-old man who received a cadaveric liver allograft for autoimmune and hepatopulmonary syndrome. The patient was admitted with symptoms of progressive vomiting and diarrhea 16 months after transplantation. Laboratory studies showed abnormal liver functions, and abdominal magnetic resonance imaging (MRI) showed a 76-mm heterogeneous mass in the liver. Histological examination showed a malignant lymphoid neoplasm with plasmablastic features. Plasmablastic lymphoma (PL) is rare in the post-transplantation period. To the best of our knowledge, only 25 well-documented cases of posttransplant PL, including ours, have been described.

Portal hypertension and acute liver failure as uncommon manifestations of primary amyloidosis.

Hepatic involvement in primary amyloidosis is an infrequent challenge to the hepatologist. Although usually asymptomatic, amyloidosis may have unusual manifestations. Liver biopsy is an important diagnostic tool for this condition. Herein, we report three cases of portal hypertension related to primary hepatic amyloidosis, one of them in the form of acute liver failure.

Operational tolerance after liver transplantation, more common than we think: a case report.

Operational tolerance after liver transplantation has been described in around 20% of the recipients. These patients are able to maintain a normal graft function in the absence of immunosuppressive drugs, thus being free of adverse effects that are common and frequently severe. Here we present a well-documented case of operational tolerance after liver transplantation and discuss current concepts on this topic with emphasis on recent findings that will potentially allow for identifying graft-tolerant patients.

Thalidomide for the treatment of metastatic hepatic epithelioid hemangioendothelioma: a case report with a long term follow-up.

Hepatic epithelioid hemangioendothelioma (HEH) is an unusual, low-grade malignant vascular tumor of the liver. Here we describe a case of a 40-year-old woman who presented with abdominal pain in the upper right quadrant and giant hepatomegaly, in which imaging studies and a fine-needle liver biopsy confirmed the presence of a large EHE with an isolated lung metastasis. After balancing all possible therapeutic modalities the patient was treated conservatively with thalidomide (300 mg/day). The drug was well tolerated with minimal toxicity and the patient continues on therapy 109 months after treatment was started with no disease progression. Current therapeutic options for HEH are discussed in light of the clinical case with particular emphasis on anti-angiogenic therapies.

Endoscopic band ligation versus propranolol for the primary prophylaxis of variceal bleeding in cirrhotic patients with high risk esophageal varices.

BACKGROUND: Gastroesophageal variceal bleeding is a common complication of portal hypertension. Current guidelines recommend thorn-blockers for primary prophylaxis. However, evidence suggests that endoscopic variceal ligation (EVL) reduce bleeding episodes. AIMS: To compare endoscopic EVL with propranolol (PPL) for primary prophylaxis of variceal bleeding. METHODS: We conducted a randomized controlled trial. Over a 9-year period, 75 patients with cirrhosis and high-risk esophageal varices (HREV) were recruited and allocated to EVL (n=39) or PPL (n=36). Primary outcome was variceal bleeding. Secondary outcomes were survival, source of bleeding and serious adverse events. Analyses were made by intention-to-treat. RESULTS: Baseline characteristics were similar. Medium follow-up was 1647+/-1096 days. complete follow-up was achieved in 85% of patients. Variceal bleeding occurred in 12% of EVL and in 25% of PPL group (p=0.17). The actuarial risks of bleeding after 2 years were similar in both groups. Overall mortality was 51% in EVL and 33% in PPL group (p=0.17). Patients in the EVL group showed a lower rate of esophageal variceal bleeding (5.1% v/s 25%, p=0.027) and a higher rate of subcardial variceal bleeding compared with PPL group (7.7% v/s 0%, p=0.027). Serious adverse events related to EVL occurred in 2 patients, including 1 death. CONCLUSIONS: The present study supports that PPL should be considered the first choice in primary prophylaxis of variceal bleeding offering similar effects and lower severe adverse events compared with EVL.

Manejo de várices gastroesofágicas: revisión de la evidencia y consenso: metodología y organización de las guías / Management of gastroesophageal varices: evidence-based review and consensus: methodology and organization of the guidelines

Introduction: There is plenty of scientific evidence regarding the management of esophageal varices, but sometimes it is contradictory. International consensuses carried out in America and Europe are evidence based, however these do not include a comprehensive analysis on the quality of the studies. The purpose of this review is to establish a national consensus, by means of relevant questions regarding the management of gastroesophageal varices, to provide detailed information on related evidence, thus, establishing reasonable behaviors based on the national scenario. Methodology: The guidelines are organized following 15 clinically relevant questions on the management of gastroesophageal varices, including primary prophylaxis, interventional pharmacological, endoscopical and radiological treatment of variceal hemorrhage until secondary prophylaxis. Quality assessment of the evidence supporting each asseveration will be descriptive and will be based mainly in the design of the studies, adapted from the recommendations of the U.S. Preventive Services Task Force. Then, the group of experts will make a recommendation for each intervention in response to each question. The consensus will be achieved by a Delphi approach of 2 rounds, and the third round will be achieved in the national consensus to be carried out in June 2010 during the Course on Advances in Gastroenterology, with the participation of the audience, using an electronic board where the questions will be answered in actual time. Preliminary results: The survey includes 15 open questions which were distributed among the 12 experts who will provide responses according to levels/degrees of evidence and recommendations. Conclusions: Definitive results of the national consensus will be presented during the Course on Advances in Gastroenterology 2010 and will be published in the Gastroenterología Latinoamericana journal. This methodology can be replicated in the future in other areas ...

Introducción: La evidencia científica en relación al manejo de las várices gastroesofágicas es abundante y muchas veces contradictoria. Los consensos internacionales realizados en América y Europa son basados en la evidencia, sin embargo, no incluyen un análisis detallado de la calidad de los estudios incluidos. El objetivo de la presente revisión es establecer un consenso a nivel nacional, a través de preguntas relevantes en el manejo de las varices gastroesofágicas, detallar la evidencia relacionada y establecer así conductas racionales, considerando la realidad nacional. Metodología: Las guías están organizadas en relación a 15 preguntas clínicas relevantes en el manejo de las várices gastroesofágicas que incluyen la profilaxis primaria, tratamiento farmacológico, endoscópico y radiológico intervencional de la hemorragia variceal hasta la profilaxis secundaria. La evaluación de la calidad de la evidencia que sustenta cada afirmación se realizará en forma descriptiva, fundamentándose primordialmente en el diseño de los estudios, adaptado de las recomendaciones realizadas por la U.S. Preventive Services Task Force. Luego el panel de expertos realizará una recomendación para cada intervención en respuesta a cada pregunta clínica. El consenso se realizará mediante una técnica Delfi de 2 rondas y la tercera ronda se realizará durante el consenso nacional a realizarse en el curso de avances en gastroenterología en junio de 2010 con participación de la audiencia mediante teclera electrónica con respuestas en tiempo real. Resultados preliminares: La encuesta incluye 15 preguntas abiertas distribuidas entre el panel de 12 expertos nacionales que deberán responder de acuerdo a la pauta de niveles de evidencia y grados de recomendación. Conclusión: Los resultados definitivos del consenso nacional serán expuestos durante el curso de avances en gastroenterología 2010 y publicados en la Revista Gastroenterología Latinoamericana. Esta metodología puede ser...

Platelet count/spleen diameter ratio for non-invasive prediction of high risk esophageal varices in cirrhotic patients.

BACKGROUND AND OBJECTIVE: Prophylaxis therapy is indicated in cirrhotic patients with large esophageal varices or small varices with red wale signs (high risk esophageal varices; HREV). Endoscopic surveillance to detect HREV is currently recommended. The objective of this study is to identify non-invasive predictors of HREV in cirrhotic patients. DESIGN AND METHODS: Adult cirrhotic patients without previous variceal bleeding were prospectively included. All patients underwent a complete biochemical workup, upper digestive endoscopy, and ultrasonographic measurement of spleen bipolar diameter. Platelet count/spleen diameter ratio (PC/SD) was calculated for all patients. The association of these variables with the presence of HREV in upper endoscopy was tested using univariate and multivariate analysis. Receiver operating characteristic (ROC) curves were constructed for variables associated with HREV. RESULTS: Sixty-seven patients were included. The prevalence rate of HREV was 50%. Age, gender (female), platelet count, spleen diameter, PC/SD ratio, total bilirrubin, prothrombin activity (INR), Child-Pugh score, clinical and ultrasonographic ascites were significantly associated with presence of HREV in univariate analysis. Age and PC/SD ratio were the parameters independently associated with HREV in a multivariate analysis, with OR 8.81 (CI 95%: 1.7-44.9) and OR 11.21 (CI 95%: 2.8-44.6) respectively. A PC/SD ratio cut-off value under 830.8 predicted HREV with 76.9% sensitivity, 74.2% specificity and 77.8% negative predictive value (ROC curve area: 0.78). CONCLUSIONS: The PC/SD ratio was significantly associated with HREV, but with suboptimal sensitivity and specificity. Therefore, the results of this study do not support the routine clinical use of PC/SD ratio for screening of HREV.

Successful treatment of severe hepatopulmonary syndrome with a sequential use of TIPS placement and liver transplantation.

Hepatopulmonary syndrome (HPS) is a complication of portal hypertension (PH) defined by the presence of liver disease, abnormal pulmonary gas exchange and evidence of intrapulmonary vascular dilatations (IPVD) producing a right to left intrapulmonary shunt. Liver transplantation (LT) is the treatment of choice; however, severe hypoxemia may contraindicate LT. The use of transjugular intrahepatic portosystemic shunts (TIPS) could be effective in HPS, although available data is limited. AIM: To report a clinical case of severe HPS treated sequentially with TIPS and LT. CASE REPORT: A 46 year old female cirrhotic patient presented with rapidly progressive dyspnea, hypoxemia (PaO2 60 mmHg, SaO2 92%) and increased alveolar-arterial oxygen gradient (A-a) (46 mmHg). She also had orthodeoxia (SaO2 87% in sitting position, but 91% in a prone position). A CT scan and pulmonary angiography were normal. Spirometric assessment showed a mild restrictive pattern and a desaturation was observed in a six-minute walking test. Contrast-enhanced echocardiography (CEE) showed intrapulmonary shunting. A HPS was diagnosed and liver transplantation was disregarded due to severe hypoxemia. The patient underwent TIPS placement. After four weeks, a significant improvement of dyspnea and a complete remission of orthodeoxia were seen. One year later, the patient was successfully transplanted. Interestingly, six months after LT, and in the absence of dyspnea, a new CEE showed persistent passing of bubbles to the left cavities. COMMENTS/CONCLUSION: Persistent right-to-left shunt after TIPS placement and liver transplantation in spite of the improvement of pulmonary function tests suggests long-term persistence of structural changes in the pulmonary vascular tree after liver transplantation. Because of lack of data, it is not possible to recommend the routine use of TIPS as a part of the conventional management of HPS. However, in patients with severe hypoxemia TIPS placement can reasonably be used as a bridge towards transplantation.

Non-alcoholic fatty liver disease and its association with obesity, insulin resistance and increased serum levels of C-reactive protein in Hispanics.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder of the liver, which may progress to fibrosis or cirrhosis. Recent studies have shown a significant impact of ethnicity on susceptibility to steatosis-related liver disease. AIMS: To estimate the prevalence of NAFLD among Chilean Hispanics as well as the clinical and biochemical variables associated with the disease. METHODS: Population-based study among Chilean Hispanics. The diagnosis of NAFLD was made on the basis of ultrasound evidence of fatty liver and absence of significant alcohol consumption and hepatitis C virus infection. RESULTS: A total of 832 Hispanic subjects were included. Ultrasound findings revealed diffuse fatty liver in 23% of the subjects. Variables associated with fatty liver in multivariate analysis were body mass index >26.9 [odds ratio (OR) 6.2; 95% confidence interval (CI) 3.3-11.5], abnormal aspartate aminotransferase levels (OR 14; 95% CI 8.2-23.7), presence of insulin resistance as measured by homoeostasis model assessment-insulin resistance (OR 3; 95% CI 1.8-4.8) and serum levels of high-sensitivity C-reactive protein (hs-CRP) greater than 0.86 mg/L (OR 2.9; 95% CI 1.6-5.2). Among subjects with NAFLD, levels of hs-CRP were similar regardless of the alanine aminotransferase (ALT) level. CONCLUSIONS: Chilean Hispanics exhibit a high prevalence of NAFLD. Obesity, insulin resistance, abnormal aminotransferase levels and elevated hs-CRP were independently associated with the presence of NAFLD. ALT elevation underestimates the presence of ultrasonographical fatty liver, whereas hs-CRP is a sensitive independent marker of NAFLD, which may be useful for detecting fatty liver in the general population.

Nonalcoholic fatty liver disease in women with polycystic ovary syndrome.

BACKGROUND/AIMS: Insulin resistance is a common feature of both nonalcoholic fatty liver disease (NAFLD) and polycystic ovary syndrome (PCOS), therefore, we hypothesize that PCOS and NAFLD may coexist. The aim of the present study was to determine the frequency and characteristics of NAFLD in women with PCOS. METHODS: A prospective study of patients with PCOS and no current pharmacological treatment was conducted. NAFLD was diagnosed by abdominal ultrasound following exclusion of alcohol consumption, viral, or autoimmune liver disease. Anthropometric variables, serum levels of glucose, insulin, lipids and aminotransferases, and HOMA index were determined. RESULTS: Forty-one PCOS patients (mean age: 24.6+/-7.2yr, mean body mass index [BMI]: 30.3+/-7.0kg/m(2)) were included; 26 of 41 PCOS patients (63.4%) had insulin resistance and 17 (41.5%) had NAFLD. Nine of the NAFLD patients (64%) also had abnormal aminotransferases. Women with NAFLD and PCOS had a higher HOMA index and a higher waist-hip ratio than those with normal ultrasound. Patients with PCOS showed a higher frequency of NAFLD (41% vs. 19%) and insulin resistance (63% vs. 35.5%) than a control group. CONCLUSIONS: NAFLD is frequent in patients with PCOS confirming a relevant clinical association between these two conditions. Women with PCOS should be screened for liver disease.

Successful liver transplantation and delivery in a woman with fulminant hepatic failure occurring during the second trimester of pregnancy.

BACKGROUND: Severe liver dysfunction occurring during pregnancy is an unusual but dramatic event that poses special technical and ethical issues because it involves two lives. METHODS AND RESULTS: We report the case of a 35-year-old woman with cryptogenic fulminant hepatic failure who underwent successful orthotopic liver transplantation at 22 weeks of pregnancy. After a relatively uneventful post-operative course she delivered a normal offspring at the 27th week of gestation. There were no obstetrical complications and neonatal outcome was excellent. After a year of follow-up, the patient is doing well,and the newborn has exhibited normal psychomotor and weight/height development. CONCLUSION: This case illustrates the challenge of treating fulminant hepatic failure during pregnancy and demonstrates that liver transplantation is a feasible therapeutic option for treatment of patients with this condition, allowing successful completion of pregnancy.

Gallbladder disease is associated with insulin resistance in a high risk Hispanic population.

BACKGROUND/AIMS: We tested whether cholesterol gallstone disease (GS) is associated to insulin resistance and serum C-reactive protein (CRP) in a high risk population. METHODS: This was a nested case-control study on 881 Chilean subjects that included clinical examination, abdominal ultrasound and blood chemistries. Insulin resistance was determined by the homeostasis model assessment index (IR-HOMA). RESULTS: Compared to controls (n = 582), age and sex adjusted median IR-(HOMA) was significantly elevated in subjects with GS (n = 299) (P < 0.001). Risks of GS in subjects with insulin resistance and different body mass index (BMI) were: BMI < 25, 2.2 (1.1-4.7); BMI 25-30, 1.5 (0.9-2.5) and BMI > 30, 1.7 (1.0-2.9). Risk of GS in subjects with metabolic syndrome was 1.7 (CI, 1.2-2.5) and with fatty liver, 1.5 (1.1-2.2). Risk of GS in subjects with CRP > 1 mg/dL was 1.0 (0.7-1.7). CONCLUSIONS: GS is associated to insulin resistance, fatty liver and to metabolic syndrome, but not to serum CRP in a high risk Hispanic population. Insulin resistance could have a major role in the pathogenesis of GS favoring the production of cholesterol supersaturated bile and altering gallbladder function.

Increased orocecal transit time in patients with nonalcoholic fatty liver disease.

Intestinal bacterial overgrowth (IBO) has been suggested to play a pathogenic role in patients with nonalcoholic fatty liver disease (NAFLD). Delayed intestinal transit may contribute to IBO development. Ten nondiabetic patients with NAFLD and abnormal liver enzymes were recruited. Ten healthy individuals, matched by sex, age, and body mass index, were used as controls. Orocecal transit time (OCTT) was measured by the lactulose breath test. Anti-endotoxin core antibodies (EndoCAb) were determined. The effect of oral norfloxacin (400 mg BID during 2 weeks) on liver enzymes, lactulose breath test, and EndoCAb was also studied. NAFLD patients had higher basal breathed H2 and prolonged OCTT compared to controls (127 +/- 61 vs. 57 +/- 23 min, respectively; P = 0.0037). EndoCAb titers were similar in NAFLD patients and controls. Norfloxacin administration had no effect on ALT levels, lactulose breath test, or EndoCAb titers in patients with NAFLD. The present data show evidence of deranged intestinal motility in nondiabetic patients with NAFLD and support the hypothesis that NAFLD could be linked to endotoxin-induced liver damage of intestinal origin.

[Natural history of cholelithiasis and incidence of cholecystectomy in an urban and a Mapuche rural area]. / Historia natural de la colelitiasis. Incidencia de colecistectomía en un área urbana y una rural mapuche, en la última década.

BACKGROUND: Cholelithiasis is the second cause of hospital admissions in Chile. AIM: To study the prevalence of symptomatic gallstone disease and opportunity of cholecystectomy in La Florida, Santiago and among Mapuche Indians in Huapi Island. PATIENTS AND METHODS: In the period 2000-2001, we contacted to 71% (1127 subjects) and to 61% (145 subjects) patients of La Florida and Huapi Island, respectively, that had previously participated in an epidemiological study on cholelithiasis in 1993. We defined symptomatic gallstone patients as those with a history of biliary colic. Each patient was subjected to gallbladder ultrasound. RESULTS: In 1993, 30-35% of gallstone patients were symptomatic (approximately 70% women). During the lapse 1993-2001, only 50% of subjects from La Florida and 25% of patients from Huapi Island were cholecystectomized (p < 0.05). Fifty percent of cholecystectomies were emergency operations. In 38 symptomatic Mapuche Indians from Huapi, cholecystectomy was indicated in 2001. After five months of the indication, only one of these subjects had been operated. Laparoscopic cholecystectomy represented 40% of all cholecystectomies performed in the National Health Service Hospitals. CONCLUSIONS: This study demonstrates an unacceptable high prevalence of symptomatic gallstone patients remaining non-operated in both the urban and rural communities. This reciprocally correlates with the high frequency of emergency cholecystectomies and the high incidence of gallbladder cancer among Chileans. This study contrasts negatively with the situation of Scotland, where 73.5% of cholecystectomies were laparoscopic in 1998-1999. To reach Scotland standards, the Chilean Public Health System should increase the number of cholecystectomies from 27,000 in 2001 to 57,510

Historia natural de la colelitiasis: incidencia de colecistectomía en un área urbana y una rural mapuche, en la última década / Natural history of cholelithiasis and incidence of cholecystectomy in an urban and a Mapuche rural area

Background: Cholelithiasis is the second cause of hospital admissions in Chile. Aim: To study the prevalence of symptomatic gallstone disease and opportunity of cholecystectomy in La Florida, Santiago and among Mapuche Indians in Huapi Island. Patients and methods: In the period 2000-2001, we contacted to 71 percent (1127 subjects) and to 61 percent (145 subjects) patients of La Florida and Huapi Island, respectively, that had previously participated in an epidemiological study on cholelithiasis in 1993. We defined symptomatic gallstone patients as those with a history of biliary colic. Each patient was subjected to gallbladder ultrasound. Results: In 1993, 30-35 percent of gallstone patients were symptomatic (&70 percent women). During the lapse 1993-2001, only 50 percent of subjects from La Florida and 25 percent of patients from Huapi Island were cholecystectomized (p <0.05). Fifty percent of cholecystectomies were emergency operations. In 38 symptomatic Mapuche Indians from Huapi, cholecystectomy was indicated in 2001. After five months of the indication, only one of these subjects had been operated. Laparoscopic cholecystectomy represented 40 percent of all cholecystectomies performed in the National Health Service Hospitals. Conclusions: This study demonstrates an unacceptable high prevalence of symptomatic gallstone patients remaining non-operated in both the urban and rural communities. This reciprocally correlates with the high frequency of emergency cholecystectomies and the high incidence of gallbladder cancer among Chileans. This study contrasts negatively with the situation of Scotland, where 73.5 percent of cholecystectomies were laparoscopic in 1998-1999. To reach Scotland standards, the Chilean Public Health System should increase the number of cholecystectomies from 27,000 in 2001 to 57,510