Paola Viviani G

Curva nacional de distribución de peso al nacer según edad gestacional: Chile, 1993 a 2000

Background: The World Health Organization recently defined the criteria for constructing birth weight curves using population based data. Aim: To construct a national curve of weight, size and ponderal index at birth for Chile, following the criteria suggested by the World Health Organization (WHO) expert committee report from 1995. Material and methods: A national database from the Chilean Institute for Statistics was used. All alive singleton deliveries during the period from 1993 to 2000 were included. A birth weight curve for the total population as well as for size and ponderal index at birth was construted, including percentile distribution, mean and standard deviation of values for gestational age. Stratification by sex was performed. Results: A total of 2,049,446 singleton deliveries were analyzed. The 10 percentiles (raw data) for birth weight throughout gestation from 22 to 42 weeks were: 470, 520, 560, 630, 660, 749, 810, 926, 1,031, 1,160, 1,320, 1,480, 1,680, 1,920, 2,190, 2,500, 2,750, 2,910, 3,010, 3,080 and 3,090 g, respectively. Conclusions: A national birth weight for Chilean population (a predominant Hispanic population) was constructed. There are not differences between this curve and the standard proposed by WHO (population from California, USA) suggesting that under comparable perinatal indices, ethnicity is not a relevant factor determining birth weight (Rev Med Chile 2004; 132: 1155-65)

Neumonía adquirida en la comunidad en el adulto hospitalizado: Cuadro clínico y factores pronósticos

Background: Community-acquired pneumonia (CAP) is a serious health problem in Chile. Aim: To study prognostic factors on admission and outcome of CAP, in immune competent adult patients, hospitalized in the Catholic University Clinical Hospital. Patients and methods: All adult patients admitted with a CAP in a period of 2 years were prospectively studied. Patients with immunodeficiency, solid tumors or receiving oral adrenal steroids were excluded from the study. Results: In the study period, 463 patients (69±19 years, 55% male) were evaluated. Ninety four percent were treated with 2nd or 3rd generation cephalosporins. Mean hospital length of stay was 10 days. Mortality during hospital stay was 8% and in the ensuing 30 days, it was 12%. Bacterial etiology was established in 25% of cases. The most frequent pathogens isolated were Streptococcus pneumoniae (10.2%), Haemophilus influenzae (3.7%), Staphylococcus aureus (2.8%) and Gram negative bacilli (5.2%). Admission prognostic factors associated with hospital mortality were: an age over 65 years, presence of comorbidity, chronic neurological and hepatic disease, suspicion of aspiration, duration of symptoms for less than 3 days, presence of dyspnea and altered mental status, absence of cough, fever and chills; low blood pressure, tachypnea, metabolic acidosis, hypoxemia, high blood urea nitrogen, hypernatremia, hyperkalemia, hyperphosphatemia, hypoalbuminemia, multilobar radiographic pulmonary infiltrates, bacteremia, high risk categories of the Fine Index (IV and V), and admission to Intermediate Care Unit or ICU. Conclusions: The features of community acquired pneumonia of these patients are similar to those reported abroad (Rev Med Chile 2002; 130: 1373-82).

Influencia de la personalidad y el estilo de aprendizaje en la elección de especialidad médica

Background: Several studies indicate that doctors who work in the same area of the medical profession tend to behave somehow similarly. Thus, it has been suggested that personality relates to the medical specialty choice. However, it is not known whether people selfselect into the medical specialties according to their personality or the professional practice in a particular field influences their behavior. Aim: To explore the possible association between the graduate’s personality features and learning styles and their chosen specialty. Subjects and Methods: The psychological preferences and learning styles of 65 students of the 2001-graduating cohort of the Pontificia Universidad Catolica de Chile School of Medicine were evaluated with the Myers Briggs Type Indicator and the Kolb Learning Style Inventory, respectively. These variables were correlated with the information of their specialty choice or occupation two years after graduation. Results: Graduates distributed unevenly in different areas of the medical profession. Surgical specialties concentrated a larger proportion of extraverted, intuitive and structured doctors, whereas in Pediatrics and Internal Medicine predominated intuitive and people-oriented MD’s. Primary Care concentrated individuals with introverted, intuitive and flexible attitudes. Convergent learners (interested in problem-solving) preferred Surgery and Primary Care whereas Assimilator learners

Tipos psicológicos y estilos de aprendizaje de los estudiantes que ingresan a Medicina en la Pontificia Universidad Católica de Chile

abstracto-reflexivas tenganventajas en el ciclo basico de la carrera y los concreto-activos en el ciclo clinico e internado. Dehecho, se han reportado diferencias en la habilidaddiagnostica de aprendices abstractos y concretos 31 ,destacandose los abstractos por su capacidad deestructurar el pensamiento y los concretos por suflexibilidad de pensamiento.C ONCLUSIONES GENERALES En resumen, de cada 10 estudiantes que ingresana estudiar medicina en la PUC, 7 se caracterizanpor analizar la informacion de un modo logico,objetivo e imparcial o por tener una posturaestructurada y decidida en la vida. El fuerte deestos estudiantes es la capacidad de asimilar grancantidad de informacion y abstraer los conceptosy patrones generales. Tienen una tendencia masreflexiva que activa, por lo que evaluanexhaustivamente las alternativas de accion.Por otra parte, 30% que posee el perfil opues-to, basa sus decisiones en consideraciones perso-nales, privilegia la armonia entre las personas, ytiene una actitud flexible y abierta ante la vida ysus posibilidades. Las fortalezas de estos estudian-tes residen en su capacidad para aprender de laexperiencia directa y trabajar en equipo; en suaprecio y cuidado por los detalles, y en suvaloracion de las relaciones interpersonales.Sin lugar a dudas, las caracteristicas de personali-dad y estilos de aprender atraviesan la vida academicade cada estudiante, influyendo en la adquisicion tantode conocimientos como de habilidades y actitu-des

Influyen las características psicológicas y los estilos de aprendizaje en el rendimiento académico de los estudiantes de medicina? Un estudio retrospectivo

BACKGROUND The degree of difficulty we experience while learning different concepts and skills depends, among other things, on our psychological features and learning style. This may be particularly true for medical students, whose formation involves the acquisition of multiple cognitive, affective and psychomotor skills. AIM To assess whether the psychological features and learning styles of medical students are associated with their academic performance. SUBJECTS AND METHODS The psychological preferences and learning styles of 66 students of the 2001-graduating cohort were determined with the Myers Briggs Type Inventory (MBTI) and the Kolb Learning Style Inventory (LSI), respectively. The academic performance was assessed by the Calificación Médica Nacional (CMN), Chile and by the marks obtained during the Basic (1st to 3rd), Preclinical (4th and 5th) and Clinical (6th and 7th) years of undergraduate training. RESULTS The psychological features, together with the sex of students were found to be associated with the performance in the Preclinical and Clinical years, and to the CMN. In men, the interest and ability to communicate with people and the concern for harmony, and in women the tendency to function in a systematic and orderly way are the features associated to high academic performance. No associations were found between learning styles and academic performance. CONCLUSIONS The finding that the psychological preferences of medical students are relevent to their academic performance opens a new perspective to analyze the medical education and to design programs aimed at improving learning.

Pruebas cutáneas de hipersensibilidad inmediata en una población pediátrica seleccionada

Background: Skin prick test (SPT) of immediate hypersensitivity is a main instrument in the diagnosis of allergy. Aim: To demonstrate the applicability of skin prick test in different age groups. Patients and Methods: We studied children and adolescents with the diagnosis of allergy in the Pediatric Respiratory Laboratory of the Catholic University of Chile, from January 2001 to March 2002. The SPT was performed using a standardized technique. The allergens were applied on the volar surface of the forearm in children older than 4 years of age and in younger children it was applied on their back. For study purposes we separated them into three age groups: GI ≤2 years and 11 months, GII from 3 to 4 years and 11 months, GIII ≥5 years. Results: We studied 408 children, aged between 8 months and 15 years. The SPT was applied to all patients with no adverse effects of any kind. There was a positive reaction in 57.7% of children. The reaction was positive in 37% in G1, 39% in GII and 65% in GIII (p <0.001). The predominant allergens for each group were dust mites (Dermatophagoides pteronissinus and farinae). Conclusions: SPT was useful when used on a selected pediatric population. The frequency of sensitization increased significantly with age. However, more than one third of children between 2 and 4 years of age tested positive to one or more allergen, demonstrating its applicability in this age group (Rev Med Chile 2005; 133: 195-201). (Key Words: Antigens, Dermatophagoides; House dust mites; Hypersensitivity; Skin tests)

Pólipos vesiculares: correlación entre hallazgos ecográficos e histopatológicos

BACKGROUND Gallbladder polyps are becoming a common finding. The management of these polyps is complicated considering that they can bear malignant lesions. AIM To analyze the ultrasonographic and histopathologic findings of patients operated due to gallbladder polyps. PATIENTS AND METHODS The records of patients with ultrasonographic diagnosis of gallbladder polyp and that underwent cholecystectomy in a thirteen years period were reviewed, collecting their demographic, ultrasonographic and histopathological data. RESULTS One hundred and twenty three patients were operated. The mean age was 44+/-13 years, and 69% were women. The mean size of polyps in ultrasonography was 7.3+/-5 mm. Histopathology confirmed the presence of polyps in 79% of patients, with a mean size and number of lesions of 5.1+/-3.8 mm and 2.1+/-2, respectively. Nine percent of polyps were greater than 10 mm, and single polyps were significantly larger than the multiple ones (p =0.003). Four cases of adenoma (3.2%) were diagnosed; one of them had in situ carcinoma. All were single and larger than 10 mm. We found a significant correlation between ultrasonographic and histopathological polyp size determination (r =0.47; p =0.002). Polyp size was also a predictor of the presence of adenoma (p =0.043; confidence intervals: 1.006-1.424). CONCLUSIONS There is a good correlation between the size of the gallbladder polyp in ultrasonography and the size in the histopathology report. Gallbladder adenoma is uncommon and it correlates with the size of the polyp. In this series, size was the only predictor of the presence of adenoma.

Características psicológicas y estilos cognitivos de estudiantes de medicina y de otras carreras de la Pontificia Universidad Católica de Chile

Background: The similarity between the psychological features of medical school freshmen of different cohorts suggests that Medicine attracts students with specific psychological types. However, it is also possible that medical students are similar to the students admitted to any other career with high admission requirements. Aim: To determine if medical school freshmen are different from those of Engineering, Architecture, Psychology and Journalism. Subjects and methods: The Spanish version of the Myers Briggs Psychological Type Indicator (MBTI) was applied to two cohorts of Medical School freshmen (90 students of the 2000 cohort and 91 students of the 2001 cohort) and to a sample of 669 freshmen from the careers of Engineering, Psychology, Architecture and Journalism. Results: Students entering Medical School are similar to the students admitted to Engineering and different from those that entered Architecture, Psychology and Journalism in the Pontificia Universidad Catolica de Chile in 2000 and 2001. Medicine attracts a larger proportion of concrete and practical students that have an objective and systematic approach to study and to life in general. Unlike Medicine, Psychology and Architecture attract more students that have a cognitive style characterized by an intuitive perception, and that face life with an open and flexible attitude. Conclusions. This study reveals that the psychological features of undergraduate students are associated to their career choice. These psychological variables, therefore, may be relevant to the students’ vocational preferences and possibly to their future specialty choice (Rev Med Chile 2004; 132: 809-16). (Key Words: Education, medical; Personality inventory; Psychological tests; Students, medical)

Factores determinantes en la aparición de fibrilación auricular post-cirugía de revascularización miocárdica: Un estudio prospectivo

Background: Atrial fibrillation (AF) is a relevant complication after coronary artery bypass grafting (CABG). However there is controversy regarding possible contributing factors. Aim: To study the incidence of AF, its risk factors and its repercussion on hospital stay and charges, in patients undergoing CABG. Material and methods: We prospectively collected information from all patients undergoing CABG in our institution, including demographic, surgical and laboratory variables. Exclusion criteria were chronic AF, recent onset AF and patients who needed additional surgical procedures. The primary endpoint was the incidence of AF during the hospital stay. Secondary endpoints were hospital length of stay and hospital charges. Results: We included 250 patients aged 62±9 years (199 males) in the analysis. Incidence of AF was 22% (54 patients). Multivariable analysis showed that age (Odds Ratio (OR) =1.10), previous CABG (OR =9.39), previous use of ACE inhibitors (OR =3.28) and aortic clamp >57 minutes (OR =3.97) were significantly associated with an increased risk of postoperative AF. Previous use of beta-blockers was associated with risk reduction (OR =0.43). Patients who developed AF had a longer hospital stay (p <0.001) and higher hospital charges (p =0.003). Conclusion: AF is a frequent complication in patients undergoing CABG. Risk factors are age, time of aortic clamp, previous CABG and ACE inhibitors. Beta-blockers may prevent its occurrence. Furthermore, AF has a negative impact on both hospital stay and hospital charges (Rev Med Chile 2007; 135: 967-74).

Factores pronósticos, evolución y mortalidad en el adulto inmunocompetente hospitalizado por neumonía neumocócica adquirida en la comunidad

One hundred fifty one immunocompetent patients, aged 16 to 92 years, 58%males, were studied. Seventy five percent had other diseases, 26% were admitted to the intensive careunit and 9% needed mechanical ventilation. There were no differences in clinical features, ICUadmission or hospital length of stay among bacteremic and nonbacteremic patients. Thirty dayslethality for bacteremic and nonbacteremic patients, was 10.9% and 11.5%, respectively. Thepredictive values for lethality of Fine pneumonia severity index and CURB-65 (Confusion, Ureanitrogen, Respiratory rate, Blood pressure, 65 years of age and older) had an area under the ROCcurve of 0.8 and 0.69, respectively. Multivariate analysis disclosed blood urea nitrogen over 30 mg/dL (odds ratio (OR), 6.8), need for mechanical ventilation (OR, 7.4) and diastolic blood pressurebelow 50 mmHg (OR, 3.9), as significant independent predictors of death.