RESUMEN
We present a case of a healthy 64-year-old man whose endoscopy showed an irregular subepithelial lesion in the gastric antrum. This lesion was covered by normal mucosa. Biopsies were taken by a bite-on-bite technique. After biopsies, the patient developed arterial bleeding, which was controlled. The anatomopathological study showed a tortuous artery in the submucosa, with a marked hyperplasia of the intima and the internal elastic lamina. These findings were consistent with a gastric arteriovenous malformation versus a Dieulafoy's lesion. This case demonstrates the risk of the bite-on-bite biopsy technique. In our country we have endoscopic ultrasound to assess these lesions, however its availability is low.
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Gastropatías , Enfermedades Vasculares , Malformaciones Vasculares , Masculino , Humanos , Persona de Mediana Edad , Endoscopía Gastrointestinal , Hemorragia , Biopsia , Hemorragia GastrointestinalRESUMEN
INTRODUCTION: Helicobacter pylori infection affects approximately 70% of the Chilean population. It is a public health problem whose eradication treatment is part of the explicit health guarantees in Chile. OBJECTIVES: Characterize the most widely used H. pylori first-line eradication therapies in our environment and evaluate their efficacy. METHODS: A retrospective observational study was carried out where, in patients with certified H. pylori infection, the eradication therapy indicated by the treating physician, its efficacy, adherence and adverse effects, in addition to the eradication certification method used, were evaluated. RESULTS: 242 patients and 4 main therapies were analyzed: standard triple therapy, dual therapy, concomitant therapy, and bismuth quadruple therapy. Eradication rates of 81.9% (95% CI 74.44-87.63), 88.5% (95% CI 73.13-95.67), 93.7% (95% CI 78.07-98.44) and 97.6% (95% CI 84.81-99.67) were observed respectively, with concomitant therapy (RR: 1.14; 95% CI 1.01-1.29; p=.028) and quadruple therapy with bismuth (RR: 1.19; 95% CI 1.09-1.31; p<.001) being significantly more effective than standard triple therapy. Regarding the rate of reported adverse effects, it was 58.5% (95% CI 50.66-65.92), 35.4% (95% CI 24.6-48.11), 22.9% (95% CI 81-37.14) and 63.4% (95% CI 47.8-76.64), having the dual and concomitant therapy significantly fewer adverse effects compared with standard therapy. CONCLUSIONS: Quadruple therapies are superior to standard triple therapy and should be considered as first-line treatment in Chile. Dual therapy is promising. More studies will be required to determine which therapies are most cost-effective.
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Infecciones por Helicobacter , Helicobacter pylori , Amoxicilina/uso terapéutico , Antibacterianos/efectos adversos , Bismuto/uso terapéutico , Chile , Quimioterapia Combinada , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Inhibidores de la Bomba de Protones/uso terapéuticoRESUMEN
OBJECTIVES: To: 1. Describe the frequency of viral RNA detection in stools in a cohort of patients infected with SARS-CoV-2, and 2. Perform a systematic review to assess the clearance time in stools of SARS-CoV-2. METHODS: We conducted a prospective cohort study in two centers between March and May 2020. We included SARS-CoV-2 infected patients of any age and severity. We collected seriated nasopharyngeal swabs and stool samples to detect SARS-CoV-2. After, we performed a systematic review of the prevalence and clearance of SARS-CoV-2 in stools (PROSPERO-ID: CRD42020192490). We estimated prevalence using a random-effects model. We assessed clearance time by using Kaplan-Meier curves. RESULTS: We included 32 patients; mean age was 43.7±17.7 years, 43.8% were female, and 40.6% reported gastrointestinal symptoms. Twenty-five percent (8/32) of patients had detectable viral RNA in stools. The median clearance time in stools of the cohort was 11[10-15] days. Systematic review included 30 studies (1392 patients) with stool samples. Six studies were performed in children and 55% were male. The pooled prevalence of viral detection in stools was 34.6% (twenty-four studies, 1393 patients; 95%CI:25.4-45.1); heterogeneity was high (I2:91.2%, Q:208.6; p≤0.001). A meta-regression demonstrates an association between female-gender and lower presence in stools (p=0.004). The median clearance time in stools was 22 days (nineteen studies, 140 patients; 95%CI:19-25). After 34 days, 19.9% (95%CI:11.3-29.7) of patients have a persistent detection in stools. CONCLUSIONS: Detection of SARS-CoV-2 in stools is a frequent finding. The clearance of SARS-CoV-2 in stools is prolonged and it takes longer than nasopharyngeal secretions.
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COVID-19 , SARS-CoV-2 , Adulto , COVID-19/diagnóstico , COVID-19/epidemiología , Niño , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , ARN Viral , Esparcimiento de VirusRESUMEN
BACKGROUND: The risk of neoplasia in gallbladder polyps seems to be low, but the evidence from populations at high-risk of gallbladder cancer is limited. We aimed to estimate the risk and to identify the factors associated with neoplastic polyps in a high-risk Hispanic population. METHODS: A retrospective cohort was recruited between January 2010 and December 2019 at a Chilean university center. Multivariate survival analyses were conducted. Fine-Gray models were fitted to account for competing risks. Covariate adjustment was conducted using propensity scores. The main outcome was the development of gallbladder adenomas or adenocarcinoma. RESULTS: Overall, 748 patients were included, 59.6% underwent cholecystectomy. The median follow-up of patients not subjected to cholecystectomy was 54.7 months (12-128.6 months). Seventeen patients (2.27%) developed the outcome. After adjustment by age, sex, intralesional blood flow, lithiasis and gallbladder wall thickening, only polyp size (≥10 mm, adjusted-HR: 15.01, 95%CI: 5.4-48.2) and number of polyps (≥3 polyps, adjusted-HR: 0.11, 95%CI: 0.01-0.55) were associated with neoplasia. CONCLUSION: In a Hispanic population at high-risk for gallbladder cancer, gallbladder polyps seem to have a low risk of neoplasia. Polyp size was the main risk factor, while having multiple polyps was associated with an underlying benign condition.
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Carcinoma in Situ , Enfermedades de la Vesícula Biliar , Neoplasias de la Vesícula Biliar , Pólipos , Carcinoma in Situ/patología , Estudios de Cohortes , Estudios de Seguimiento , Vesícula Biliar/patología , Enfermedades de la Vesícula Biliar/patología , Enfermedades de la Vesícula Biliar/cirugía , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Humanos , Pólipos/epidemiología , Pólipos/patología , Pólipos/cirugía , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Análisis de SupervivenciaRESUMEN
BACKGROUND AND AIMS: Abdominal paracentesis is an area that every general physician should know about, and the current learning model is unsafe for patients. Simulation allows students to develop their skills prior to clinical confrontation with minimal risks. The aims of this study were to design and evaluate a paracentesis simulation workshop for undergraduate students. METHODS: A workshop was implemented using a specially designed and validated simulation model for abdominal paracentesis. The simulated technique considered the recognition of materials, operator equipment, asepsis, anesthesia, puncture and obtaining liquid, collecting samples for analysis, withdrawal of the material and occlusion. A 24-point direct observation checklist was administered to assess the student. We assessed two students at the beginning of the workshop and all the students at the end. A perception survey was applied to attendees at the end of the workshop. RESULTS: 247 students were included and a workshop that involved 8 students per session was held. Students significantly improved their skills comparing pre- and post-evaluation results [13.36±4.46 (55.7%) vs. 22.3±1.83 (92.9%) respectively (n=69) p<0.001]. The students' perception questionnaire (n=38) showed that the training sessions were highly valued, averaging 4.8±0.38 on a Likert scale of 1-5. CONCLUSIONS: Simulated training in abdominal paracentesis is a very good teaching method. This teaching methodology should be highly recommended as an educational strategy in medicine because it could accelerate the acquisition of clinical skills in a safe learning environment.
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Educación de Pregrado en Medicina/métodos , Paracentesis/educación , Entrenamiento Simulado , Competencia Clínica , Educación/organización & administración , Femenino , Humanos , Masculino , Modelos Anatómicos , Adulto JovenRESUMEN
Goodpasture Syndrome is described as a single episode disease entity. It is diagnosed with the demonstration of antiglomerular basement (anti-GBM) antibodies in plasma or renal tissue. Although the recurrence of anti-GBM disease is rare, it has been reported in up to 3% of cases. Recurrence with negative anti-GBM antibodies in plasma is even less frequent We report a 63 years old male in whom anti-GBM disease recurred without detectable anti-GBM antibodies in plasma, despite having positive antibodies at the onset.
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Enfermedad por Anticuerpos Antimembrana Basal Glomerular/patología , Autoanticuerpos/análisis , Antibacterianos/uso terapéutico , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/diagnóstico por imagen , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/tratamiento farmacológico , Biopsia , Ciclofosfamida/uso terapéutico , Técnica del Anticuerpo Fluorescente , Humanos , Enfermedades Renales/patología , Glomérulos Renales/patología , Masculino , Persona de Mediana Edad , Prednisona/uso terapéutico , Recurrencia , Combinación Trimetoprim y Sulfametoxazol/uso terapéuticoRESUMEN
BACKGROUND: Simulation is a useful training tool for undergraduate medical students. A valid instrument is needed to assess students' perception of simulation workshops. AIM: To adapt and validate an instrument to assess the undergraduate medical student's perception of simulation workshops of clinical procedures. MATERIAL AND METHODS: Delphi Methodology was used to adapt the instrument. Exploratory and confirmatory analyses were performed to determine the construct validity and Cronbach's Alpha (0 to 1) for internal consistency of the instrument. RESULTS: A Delphi panel of 10 experts adapted a seven-item questionnaire (Likert scale 1-5; ranging from 7 to 35) and four open-questions. After 3-delphi-rounds, the instrument was administered to 210 students in six simulation training programs (Paracentesis, Cardiopulmonary Resuscitation, Airway management, Sutures, Thoracentesis and Nursing Procedures). The instrument was considered unidimensional in the factorial analysis. The overall median (Q1-Q3) score was 34 ranging from 32 to 35 and the Cronbach Alpha coefficient was 0.72, indicating a good reliability. CONCLUSIONS: The perception questionnaire is a useful and reliable instrument to assess students' perceptions of clinical simulations.
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Competencia Clínica/normas , Educación de Pregrado en Medicina/métodos , Percepción , Entrenamiento Simulado/métodos , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios/normas , Técnica Delphi , Análisis Factorial , Retroalimentación Formativa , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Procedimientos Quirúrgicos Operativos/educación , Procedimientos Quirúrgicos Operativos/psicologíaAsunto(s)
Neoplasias Pancreáticas/secundario , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patología , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Cáncer Papilar Tiroideo/cirugía , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Resultado del TratamientoRESUMEN
Background: The effectiveness of dietary therapy to induce remission of eosinophilic esophagitis (EoE) has been evaluated over the last decades and summarized in meta-analyses. Choosing the dietary modality, identifying the most suitable patients, and implementing specific prerequisites are essential to ensure long-term success. Summary: Impractical exclusive elemental diets provided the highest remission rates in EoE; however, they are not recommended due to their numerous disadvantages and detrimental effects on patient quality of life. Allergy testing-guided diets for EoE are limited; their insufficient effectiveness and low reproducibility are due to poor accuracy of skin or serum test results in identifying EoE food triggers. Initial experiences with a six-food elimination diet have provided evidence of high and predictive effectiveness rates and paved the way for less restrictive and more efficient step-up approaches, including four-food, two-food, and most recently, milk elimination diets. Dietary treatment for EoE is challenging for patients and families and requires certain skills to ensure success in the short and long term. Key Messages: The selection of appropriate patients is essential to ensure the success of and long-term adherence to dietary treatment of EoE. As normal triggers for EoE are commonly found in the staple diet, it is important to ensure adequate nutritional substitutes to avoid nutrient deficiency risks when long-lasting feeding difficulties or extensive restrictions are present. Specialized facilities in dietary therapy should adopt patient-centered and personalized approaches in order to provide timely monitoring and support for complex cases.
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BACKGROUND: Oesophageal disorders and chronic liver disease are common worldwide and significantly impact quality of life. The intricate link between these conditions, including how oesophageal disorders like GERD, Barrett's oesophagus and oesophageal cancer affect and are affected by chronic liver disease, remains poorly understood. AIMS: To review the relationship between oesophageal disorders and chronic liver disease, evaluating epidemiology, pathophysiology and therapeutic factors. METHODS: We reviewed the literature on the relationship between oesophageal disorders and chronic liver disease, including cirrhosis, using the PubMed database RESULTS: Oesophageal disorders such as gastroesophageal reflux disease, Barrett's oesophagus, oesophageal cancer, oesophageal motor disorders and oesophageal candidiasis are prevalent among individuals with cirrhosis, exacerbating the burden of liver disease. These diseases have a multifaceted symptomatology and pathogenic basis, posing a significant challenge in cirrhotic patients that necessitates careful diagnosis and management. Additionally, therapies frequently used for these diseases, such as proton pump inhibitors, require careful consideration in cirrhotic patients due to potential adverse effects and altered pharmacokinetics. Managing oesophageal disorders in cirrhotic patients requires a cautious approach due to possible interactions with medications and the risk of adverse effects. Furthermore, symptoms associated with these conditions are often exacerbated by common interventions in patients with cirrhosis, such as band ligation for oesophageal varices. CONCLUSIONS: Oesophageal disorders are common in cirrhosis and increase the disease burden. These conditions require careful management due to complex symptoms and treatment risks. Proton pump inhibitors and other therapies must be used cautiously, as cirrhosis interventions can worsen symptoms.
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Enfermedades del Esófago , Hepatopatías , Humanos , Enfermedades del Esófago/fisiopatología , Enfermedades del Esófago/etiología , Enfermedades del Esófago/complicaciones , Hepatopatías/complicaciones , Hepatopatías/fisiopatología , Enfermedad Crónica , Cirrosis Hepática/complicaciones , Cirrosis Hepática/fisiopatología , Calidad de Vida , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/fisiopatología , Inhibidores de la Bomba de Protones/uso terapéuticoRESUMEN
Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disease of the esophagus characterized by symptoms of esophageal dysfunction such as dysphagia, food impaction, and chest pain in adults. It is associated with atopic di- seases such as allergic rhinitis, atopic dermatitis, and asthma. Diagnosis requires symptoms of esophageal dysfunction, eosinophilic inflammation in esophageal biopsies with at least 15 eosinophils per high power field, and exclusion of other causes of local or systemic eosinophilia. EoE is more common in men and has an increasing prevalence, varying globally. The pathophysiology involves TH2-mediated eosinophilic inflammation driven by food antigens, esophageal barrier dysfunction and tissue remodeling. Various therapeutic options aim for clinical and histological remission, including dietary and pharmacological treatments. Dietary therapy, topical corticosteroids and proton pump inhibitors are first-line treatments. Topical corticosteroids achieve high histological remission. Development of new therapies is ongoing. Dupilumab, an antibody against IL-4Rα, shows efficacy in achieving histological and symptomatic remission in patients unresponsive to proton pump inhibitors. Other targeted therapies with clinical trials for EoE include mepolizumab, reslizumab, cendakimab, lirentelimab, and etrasimod with variable clinical and histological results. A subgroup of patients with EoE unresponsive or with bad adherence to first line therapies or patients with multiple comorbid atopic diseases may benefit from biological therapies. This review aims to describe new therapeutic options, detailing their mechanisms, efficacy, and safety profiles.
La esofagitis eosinofílica (EEo) es una enfermedad crónica, inmunomediada del esófago, caracterizada por síntomas de disfunción esofágica como disfagia, impactación y dolor torácico en adultos. Se asocia a otras enfermedades atópicas como rinitis alérgica, dermatitis atópica y asma. El diagnóstico requiere síntomas de disfunción esofágica, inflamación eosinofílica en biopsias de esófago con al menos 15 eosinófilos por campo de aumento mayor, y exclusión de otras causas de eosinofilia local o sistémica. La EEo es más común en hombres y tiene una prevalencia en aumento. La fisiopatología incluye inflamación eosinofílica mediada por una respuesta TH2 gatillada por antígenos alimenticios, además disfunción de barrera esofágica y remodelación de tejido. Varias opciones terapéuticas tienen como objetivo la remisión clínica e histológica, incluyendo terapias dietéticas y tratamientos farmacológicos. La terapia dietética, inhibidores de bomba de protones o corticosteroides tópicos sin terapias de primera línea. Los corticosteroides tópicos alcanzan altas tasas de remisión histológica. El desarrollo de nuevas terapias se está llevando a cabo. Dupilumab, un anticuerpo contra IL-4Rα, muestra eficacia en alcanzar remisión histológica y sintomática en pacientes no responde- dores a inhibidores de bomba de protones. Otras terapias con estudios clínicos para EEo incluyen el mepolizumab, reslizumab, cendakimab, lirentelimab y etrasimod, con resultados variables. Un subgrupo de pacientes con EEo no respondedores o con mala adherencia a terapias de primera línea o con comorbilidades atópicas graves se podrían beneficiar de terapias biológicas como dupilumab. Esta revisión tiene como objetivo describir nuevas opciones tera- péuticas, detallando su mecanismo de acción, eficacia y perfil de seguridad.
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Humanos , Masculino , Femenino , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/terapia , Esófago/patología , Inhibidores de la Bomba de Protones/uso terapéutico , Esofagitis Eosinofílica/etiologíaRESUMEN
Pancreatic metastases of papillary thyroid carcinoma (PTC) are exceptional. We report a 80-year-old man consulting for obstructive jaundice and dysphonia. Abdominal ultrasonography showed biliary dilation and abdominal magnetic resonance imaging (MRI) showed a pancreatic head mass of 36 mm. A left vocal cord paralysis was confirmed and cervical computed tomography (CT) showed multiple thyroid nodules of up to 35 mm associated with bilateral cervical lymph nodes (LN). Positron emission tomography ( 18 F-FDG PET/CT) evidenced hyper-metabolic activity in bilateral cervical LN, lungs, pancreas and left intercostal soft tissue, as well as left gluteus. Thyroid biopsy reported a tall-cell variant of PTC, and endoscopic ultrasound guided fine needle aspiration (EUS-FNA) of pancreatic mass confirmed PTC metastasis. The molecular study was positive for BRAFV600E. Pancreatic metastasis from PTC can be accurately diagnosed with 18 F-FDG PET/CT and EUS-FNA, which is consistent with a predominant expression of BRAFV600E mutation and, thus, an aggressive presentation with poor short-term survival.
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Humanos , Neoplasias Pancreáticas/secundario , Neoplasias de la Tiroides/patología , Cáncer Papilar Tiroideo/patología , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Tiroidectomía , Neoplasias de la Tiroides/cirugía , Resultado del Tratamiento , Cáncer Papilar Tiroideo/cirugía , Escisión del Ganglio Linfático , Metástasis LinfáticaRESUMEN
Goodpasture Syndrome is described as a single episode disease entity. It is diagnosed with the demonstration of antiglomerular basement (anti-GBM) antibodies in plasma or renal tissue. Although the recurrence of anti-GBM disease is rare, it has been reported in up to 3% of cases. Recurrence with negative anti-GBM antibodies in plasma is even less frequent We report a 63 years old male in whom anti-GBM disease recurred without detectable anti-GBM antibodies in plasma, despite having positive antibodies at the onset.
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Humanos , Masculino , Persona de Mediana Edad , Autoanticuerpos/análisis , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/patología , Recurrencia , Biopsia , Prednisona/uso terapéutico , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Técnica del Anticuerpo Fluorescente , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/tratamiento farmacológico , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/diagnóstico por imagen , Ciclofosfamida/uso terapéutico , Enfermedades Renales/patología , Glomérulos Renales/patología , Antibacterianos/uso terapéuticoRESUMEN
Background: Simulation is a useful training tool for undergraduate medical students. A valid instrument is needed to assess students' perception of simulation workshops. Aim: To adapt and validate an instrument to assess the undergraduate medical student's perception of simulation workshops of clinical procedures. Material and Methods: Delphi Methodology was used to adapt the instrument. Exploratory and confirmatory analyses were performed to determine the construct validity and Cronbach's Alpha (0 to 1) for internal consistency of the instrument. Results: A Delphi panel of 10 experts adapted a seven-item questionnaire (Likert scale 1-5; ranging from 7 to 35) and four open-questions. After 3-delphi-rounds, the instrument was administered to 210 students in six simulation training programs (Paracentesis, Cardiopulmonary Resuscitation, Airway management, Sutures, Thoracentesis and Nursing Procedures). The instrument was considered unidimensional in the factorial analysis. The overall median (Q1-Q3) score was 34 ranging from 32 to 35 and the Cronbach Alpha coefficient was 0.72, indicating a good reliability. Conclusions: The perception questionnaire is a useful and reliable instrument to assess students' perceptions of clinical simulations.
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Humanos , Percepción , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios/normas , Competencia Clínica/normas , Educación de Pregrado en Medicina/métodos , Entrenamiento Simulado/métodos , Estándares de Referencia , Procedimientos Quirúrgicos Operativos/educación , Procedimientos Quirúrgicos Operativos/psicología , Reproducibilidad de los Resultados , Análisis Factorial , Técnica Delphi , Retroalimentación FormativaRESUMEN
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)