Estudio de sobrevida a largo plazo en pacientes adultos con enfermedades respiratorias crónicas atendidos por infección respiratoria aguda por coronavirus SARS-CoV-2 / Study of long-term survival in adult patients with chronic respiratory diseases treated for acute respiratory infection by coronavirus SARS-CoV-2

La enfermedad respiratoria aguda por coronavirus SARS-CoV-2 (COVID-19) se ha convertido en un grave problema de salud pública a nivel mundial. Objetivos: Examinar el uso de recursos sanitarios, riesgo de complicaciones y muerte en pacientes adultos con enfermedades respiratorias crónicas atendidos por COVID-19. Métodos: Estudio clínico descriptivo prospectivo realizado en pacientes adultos atendidos por COVID-19 en la Red de Salud UC Christus entre el 1 de abril y 31 de diciembre de 2020. Resultados: Se evaluaron 2.160 pacientes adultos, edad: 47 ± 17 años (rango: 18-100), 51,3% sexo masculino, 43,8% tenía comorbilidades, especialmente hipertensión (23,2%), diabetes (11,7%) y enfermedades respiratorias crónicas: asma (5%), EPOC (1,4%) y enfermedad pulmonar difusa (EPD: 0,8%). Los pacientes adultos con enfermedades respiratorias crónicas tuvieron mayor riesgo de hospitalización y uso de oxígeno suplementario; sin embargo, la evolución de los pacientes asmáticos y la sobrevida a los doce meses fue similar a los pacientes sin comorbilidades atendidos por COVID-19, mientras que en los pacientes con EPOC y EPD la admisión a la unidad de paciente crítico y riesgo de muerte fueron más elevados. En el análisis multivariado, los principales predictores clínicos asociados al riesgo de muerte en el seguimiento a doce meses en pacientes adultos con COVID-19 fueron la edad y admisión al hospital, mientras que el asma fue un factor protector. Conclusión: Los pacientes asmáticos tuvieron bajo riesgo de complicaciones y muerte asociados a COVID-19; mientras que los pacientes con EPOC y EPD tuvieron mayor riesgo de complicaciones y muerte en el seguimiento a largo plazo.

The acute respiratory disease associated to coronavirus SARS-CoV-2 (COVID-19) has become a serious public health problem worldwide. Objectives: To examine the use of healthcare resources, risk of complications and death in adult patients with chronic respiratory diseases treated for COVID-19. Methods: Prospective descriptive clinical study conducted in adult patients treated for COVID-19 in the UC Christus Healthcare Network between April 1 and December 31, 2020. Results: 2,160 adult patients were evaluated, age: 47 ± 17 years-old (range: 18-100), 51.3% male, 43.8% had comorbidities, especially hypertension (23.2%), diabetes (11.7%), and chronic respiratory diseases: asthma (5%), COPD (1,4%) and interstitial lung disease (ILD: 0.8%). Adult patients with chronic respiratory diseases were at higher risk for hospitalization and use of supplemental oxygen; however, the evolution of asthmatic patients and survival at twelve months was similar to that of adult patients without comorbidities treated for COVID-19, while in patients with COPD and ILD admission to the critical care unit and risk of death were higher. In the multivariate analysis, the main clinical predictors associated to 12-month mortality risk in adult patients with COVID-19 were age and hospital admission, while asthma was a protective factor. Conclusion: Asthmatic patients had minor risk of complications and mortality associated with COVID-19; while patients with COPD and ILD had a significant higher risk of complications and 12-month mortality.

Estudios de prevalencia del síndrome de apneas obstructivas del sueño en la población adulta / Studies of prevalence of obstructive sleep apnea syndrome in adult population

El síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) es un trastorno respiratorio común asociado con múltiples consecuencias adversas para la salud y su prevalencia ha aumentado en paralelo con el aumento de la obesidad en la población. MÉTODOS: revisión sistemática que examina los estudios de prevalencia de SAHOS en la población general. Se incluyeron los estudios transversales y los componentes transversales de los estudios longitudinales que midieron objetivamente la prevalencia de SAHOS en adultos empleando instrumentos de laboratorio. Se evaluaron cuarenta estudios poblacionales de las 8.876 publicaciones encontradas en la búsqueda sistemática realizada en PubMed y otras bases de datos. RESULTADOS: Se ha observado importantes diferencias metodológicas en los estudios poblacionales, lo cual ha determinado una amplia variación en la prevalencia de SAHOS reportada, con un valor promedio de 36,9% (IC95% 28,3-45,4%) en hombres y 24,0% (IC 95% 16,3-31,6%) en mujeres. Se ha reportado un aumento en la prevalencia de SAHOS en el curso del tiempo desde 1987 hasta el 2020. Esta condición es más prevalente en varones, aumenta progresivamente con la edad y se asocia a la obesidad. La somnolencia diurna excesiva se ha asociado al diagnóstico de SAHOS, pero sólo una fracción de los sujetos con índice de apnea-hipopnea ≥ 5 eventos/hora presentan somnolencia diurna. CONCLUSIÓN: La prevalencia de SAHOS ha aumentado en los estudios poblacionales realizados en el curso del tiempo. La variabilidad reportada en la prevalencia de SAHOS probablemente esté relacionada con los diferentes equipos y definiciones operacionales empleados en el proceso diagnóstico, y las características de los sujetos examinados, incluyendo el importante aumento de la obesidad en la población.

Obstructive sleep apnea syndrome (OSAS) is a common disorder associated with multiple adverse health consequences and its prevalence is increasing in parallel with global rising in obesity. METHODS: We have developed a systematic review to examine obstructive sleep apnea syndrome prevalence studies in adults in the general population. We included the cross-sectional studies and the cross-sectional components of longitudinal studies that objectively measured OSAS in adults using laboratory instruments. Forty studies out of 8,876 articles found by systematically searching in PubMed and other databases were included in this review. RESULTS: Substantial methodological heterogeneity in population prevalence studies has been observed, determining a wide variation in OSAS prevalence defined at an apnea-hypopnea index (AHI) ≥ 5 events/hour, the average OSAS prevalence was 36.9% (CI95% 28.3-45.4%) in men and 24.0% (CI95% 16.3-31.6%) in women. The OSAS prevalence has increased over the time. OSAS is more prevalent in men than in women and increases with age and obesity. Excessive daytime sleepiness has been suggested as the most important symptom associated to OSAS, but only a fraction of subjects with AHI ≥ 5 events/hour report daytime sleepiness. CONCLUSION: The prevalence of OSAS has increased in epidemiological studies over time. The differences in reported prevalence of obstructive sleep apnea are probably due to different diagnostic equipment, operational definitions, study design and characteristics of included subjects, including effects of the obesity epidemic.

¿El reflujo gastroesofágico y la aspiración de contenido gástrico están implicados en la etiopatogenia y la progresión de la fibrosis pulmonar idiopática? / Does gastroesophageal reflux and gastric content aspiration have some role in the pathogenesis and progression of Idiopathic Pulmonary Fibrosis?

Resumen El reflujo gastroesofágico (RGE) y la aspiración oculta de contenido digestivo están probablemente implicados en la etiopatogenia y progresión de la fibrosis pulmonar idiopática (FPI). Los mecanismos patogénicos involucrados son la disminución de la distensibilidad pulmonar y el consiguiente aumento de la presión negativa intratorácica durante la inspiración, así como la disminución de los mecanismos de control de la motilidad esofágica o del tono del esfínter esofágico inferior. La prevalencia de RGE y anomalías de la motilidad esofágica están aumentadas en los pacientes con FPI comparado con la población general. Entre los pacientes con FPI, el 67-76% demostraron exposición anormal al contenido ácido en el esófago. Sin embargo, no hubo relación entre la gravedad del RGE y la gravedad de la FPI. Los estudios que han examinado el tratamiento antirreflujo en esta población han sido escasos. Incluso, algunos datos sugieren que el tratamiento antiácido puede ser perjudicial en algunos pacientes con esta condición. Después de analizar toda la evidencia relevante encontrada hasta la fecha, concluimos que no se puede establecer una relación causal entre el RGE, la aspiración del contenido gástrico y la patogénesis de la FPI. Además, existe escasa evidencia clínica que haya examinado el tratamiento antirreflujo en pacientes con fibrosis pulmonar idiopática.

ABSTRACT Gastroesophageal reflux (GERD) and hidden aspiration of gastric contents are probably involved in the pathogenesis and progression of idiopathic pulmonary fibrosis (IPF). The pathological mechanisms involved are decreased pulmonary distensibility and consequent increase of intrathoracic negative pressure during inspiration, as well as decreased control mechanisms of esophageal motility or lower esophageal sphincter. The prevalence of GERD and oesophageal dysmotility was higher in patients with IPF as compared with general population. Among patients with IPF, 67-76% demonstrated abnormal oesophageal acid exposure. However, no relationship was demonstrated between severity of GERD and severity of IPF. Data are scant on outcomes of antireflux treatment in patients with IPF. Actually, some data suggests that antacid treatment may be deleterious in some IPF patients. After analyzing all the relevant evidence found to date, a causal relationship between GERD, gastric content aspiration and IPF pathogenesis cannot be established. There is scant evidence examining antireflux treatment in idiopathic pulmonary fibrosis patients.

Uso de corticoides sistémicos en pacientes adultos hospitalizados por neumonía adquirida en la comunidad / Clinical efficacy of corticoids treatment in hospitalized adult patients with community-acquired pneumonia

Resumen La neumonía adquirida en la comunidad (NAC) es una enfermedad infecciosa común y potencialmente grave que ocasiona elevada morbilidad y mortalidad. La terapia con corticosteroides (CS) sistémicos se ha propuesto para el manejo de pacientes adultos hospitalizados por neumonía adquirida en la comunidad. Objetivos: Evaluar la eficacia y seguridad del tratamiento con corticosteroides sistémicos en pacientes con NAC grave. Métodos: Se buscó la información actualizada en cinco bases de datos: PubMed, Scielo, Epistemonikos, Lilacs y Cochrane Library. Se evaluaron los ensayos clínicos controlados aleatorizados que examinaron la eficacia y seguridad de los corticosteroides en adultos hospitalizados con NAC grave. Resultados: Se incluyeron diez revisiones sistemáticas y quince estudios primarios que reclutaron pacientes hospitalizados con NAC grave. La terapia con corticosteroides redujo significativamente la mortalidad por todas las causas (cociente de riesgo [RR]: 0,58; IC95%: 0,40 a 0,84), fracaso clínico precoz (RR: 0,32; IC95%: 0,15 a 0,7), riesgo de síndrome de dificultad respiratoria del adulto (RR: 0,23; IC95%: 0,07 a 0,80), necesidad de ventilación mecánica (RR: 0,40; IC95%: 0,20 a 0,77) y se acortó la estancia hospitalaria (diferencia media: −2.91 días; IC95%: − 4,92 a −0,89). La terapia esteroidal aumentó el riesgo de hiperglicemia (RR: 1,72; IC95%: 1,38 a 2,14) pero no la frecuencia de hemorragia gastrointestinal (RR: 0,91; IC95%: 0,40 a 2,05). Conclusión: La terapia con corticosteroides sistémicos disminuye significativamente la mortalidad, riesgo de complicaciones y acorta la estancia hospitalaria en pacientes con NAC grave. Estos resultados deben ser confirmados por estudios controlados aleatorizados de mayor potencia.

Community-acquired pneumonia (CAP) is a common and serious infectious disease accompanied with high morbidity and mortality. Corticosteroids (CS) therapy has been proposed for community-acquired pneumonia hospitalized adult patients. However, the effectiveness of adjunctive corticosteroids on relevant clinical outcomes of CAP remains inconsistent. Objectives: We assessed the efficacy and safety of adjunctive corticosteroids therapy in severe CAP patients. Methods: Five databases: PubMed, Scielo, Epistemonikos, Lilacs and Cochrane Library were searched for related studies published up to June, 2018. Randomized controlled trials (RCTs) of corticosteroids in hospitalized adults with severe CAP were included. Results: We assessed ten systematic reviews and fifteen primary studies enrolling severe CAP hospitalized patients. Corticosteroids therapy significantly reduced all-cause mortality (risk ratio (RR): 0.58; 95%CI: 0.40 to 0.84), early clinical failure (RR: 0.32; 95%CI: 0.15 to 0.7), risk of adult respiratory distress syndrome (ARDS) (RR: 0.23; 95%CI: 0.07 to 0.80), need for mechanical ventilation (RR: 0.40; 95%CI: 0.20 to 0.77) and decreased hospital length of stay (mean difference: −2.91 days; 95%CI: −4.92 to −0.89). Corticosteroids therapy increased hyperglycemia risk (RR: 1.72; 95%CI: 1.38 to 2.14) but not gastrointestinal hemorrhage frequency (RR: 0.91; 95%CI: 0.40 to 2.05). Conclusions: Adjuvant therapy with systemic corticosteroids decreases mortality, risk of hospital complications and shortens hospital length of stay in patients with severe CAP. These results should be confirmed by adequately powered studies in the future.

Predictores clínicos de eventos adversos serios en el adulto inmunocompetente hospitalizado por neumonía adquirida en la comunidad / Clinical predictors of serious adverse events in immunocompetent adult patients hospitalized with community-acquired pneumonia

Introducción: La neumonía adquirida en la comunidad (NAC) ocasiona morbilidad y mortalidad significativa en la población adulta. Objetivos: Examinar las variables clínicas y de laboratorio medidas en la admisión al hospital que permiten predecir los eventos adversos clínicamente relevantes en pacientes adultos hospitalizados por neumonía comunitaria. Métodos: Evaluamos las variables clínicas y de laboratorio asociadas a eventos adversos serios en una cohorte de adultos hospitalizados por NAC. Los eventos adversos examinados fueron la admisión a UCI, necesidad de ventilación mecánica, shock séptico, complicaciones cardiovasculares y generales y estadía prolongada en el hospital y mortalidad a 30 días. Las variables predictoras fueron sometidas a análisis univariado y multivariado en un modelo de regresión logística. Resultados: Se evaluaron 659 pacientes, edad: 67 ± 18 años, 52% varones, 77% tenía comorbilidad, 23% fueron admitidos a la UCI, 12% requirieron ventilación mecánica, 31% presentaron complicaciones en el hospital, la estadía media en el hospital fue 9 días y 9,9% fallecieron en el seguimiento a 30 días. Las comorbilidades, inestabilidad hemodinámica y disfunción renal se asociaron con la admisión a UCI, riesgo de complicaciones y estadía prolongada en el hospital. El uso de ventilación mecánica y shock séptico fue más frecuente en pacientes con inestabilidad hemodinámica y disfunción renal. La edad avanzada, enfermedades cardiovasculares y respiratorias crónicas, sospecha de aspiración, taquipnea y disfunción renal se asociaron al riesgo de eventos cardiovasculares en el hospital. Conclusión: Las variables clínicas y de laboratorio medidas en la admisión al hospital permiten predecir el riesgo de eventos adversos serios en el adulto hospitalizado por neumonía.

Introduction: Community-acquired pneumonia (CAP) causes significant morbidity and mortality in adult population. Objectives: To assess clinical and laboratory variables measured at hospital admission associated to clinically relevant adverse outcomes in patients hospitalized with community-acquired pneumonia. Methods: We prospectively assessed clinical and laboratory variables associated to serious adverse events in a cohort of CAP hospitalized adult patients. Major adverse outcomes were admission to ICU, need for mechanical ventilation, septic shock, prolonged hospital stay, cardiovascular and in-hospital complications and 30-day mortality. The clinical and laboratory variables measured at hospital admission associated to serious adverse events were assessed by univariate and multivariate analysis using logistic regression models. Results: 659 CAP hospitalized immunocompetent adult patients were assessed, mean age: 67 years, 52% were male, 77% had comorbidities, 23% were admitted to the intensive care unit (ICU), 12% needed mechanical ventilation, 31% had hospital complication, mean hospital length of stay was 9 days and 9.9% died at 30-days follow up. Comorbidities, hemodynamic instability and renal dysfunction were associated with ICU admission, risk of complications, and prolonged hospital stay. Mechanical ventilation requirement and septic shock were more frequent in patients with hemodynamic instability and renal dysfunction. Advanced age, chronic cardiovascular and respiratory diseases, aspiration pneumonia, tachypnea, and renal dysfunction were associated with high risk of cardiovascular events in the hospital. Conclusion: The clinical and laboratory variables measured at hospital admission allow us to predict the risk of serious adverse events in CAP hospitalized adult patients.

Detección precoz de cáncer pulmonar con tomografía computarizada de tórax en pacientes con enfermedad pulmonar obstructiva crónica tabáquica / Early detection of lung cancer using computed tomography among patients with chronic obstructive pulmonary disease

Background: Chest computed tomography (CT) scan may improve lung cancer detection at early stages in high risk populations. Aim: To assess the diagnostic performance of chest CT in early lung cancer detection in patients with chronic obstructive pulmonary disease (COPD). Patients and Methods: One hundred sixty one patients aged 50 to 80 years, active or former smokers of 15 or more pack-years and with COPD were enrolled. They underwent annual respiratory functional assessment and chest computed tomography for three years and were followed for five years. Results: Chest CT allowed the detection of lung cancer in nine patients (diagnostic yield: 5.6%). Three cases were detected in the initial CT and six cases in follow-up scans. Most patients were in early stages of the disease (6 stage Ia and 1 stage Ib). Two patients were diagnosed at advanced stages of the disease and died due to complications of cancer. Two thirds of patients had nonspecific pulmonary nodules on the initial chest CT scan (100 patients, 62%). Seventy four percent had less than three nodules and were of less than 5 mm of diameter in 57%. In 92% of cases, these were false positive findings. In the follow-up chest CT, lung nodules were detected in two thirds of patients and 94% of cases corresponded to false positive findings. Conclusions: Chest CT scans may detect lung cancer at earlier stages in COPD patients.

Predictores clínicos de bacteriemia en adultos inmunocompetentes hospitalizados por neumonía adquirida en la comunidad / Clinical predictors of bacteremia in immunocompetent adult patients hospitalized for community-acquired pneumonia

Background: The clinical usefulness of blood cultures in the management of patients hospitalized with community-acquired pneumonia (CAP) is controversial. Aim: To determine clinical predictors of bacteremia in a cohort of adult patients hospitalized for community-acquired pneumonia. Material and Methods: A prospective cohort of 605 immunocompetent adult patients aged 16 to 101 years (54% male) hospitalized for CAP was studied. The clinical and laboratory variables measured at admission were associated with the risk of bacteremia by univariate and multivariate analysis using logistic regression models. Results: Seventy seven percent of patients had comorbidities, median hospital stay was 9 days, 7.6% died in hospital and 10.7% at 30 days. The yield of the blood cultures was 12.6% (S. pneumoniae in 69 patients, H. influenzae in 3, Gram negative bacteria in three and S. aureus in one). These results modified the initial antimicrobial treatment in one case (0.2%). In a multivariate analysis, clinical and laboratory variables associated with increased risk of bacteremia were low diastolic blood pressure (Odds ratio (OR): 1.85, 95% confidence intervals (CI) 1.02 to 3.36, p < 0.05), leukocytosis e" 15,000/mm³ (OR: 2.18, 95% CI 1.22 to 3.88, p < 0.009), serum urea nitrogen e" 30 mg/dL (OR: 2.23, 95% CI 1.22 to 4.05, p < 0.009) and serum C-reactive protein e" 30 mg/dL (OR: 2.20, 95% CI 1.22 to 3.97, p < 0.01). Antimicrobial use before hospital admission significantly decreased the blood culture yield (OR: 0.14, 95% CI 0.04 to 0.46, p < 0.002). Conclusions: Blood cultures do not contribute significantly to the initial management of patients hospitalized for community-acquired pneumonia. The main clinical predictors of bacteremia were antibiotic use, hypotension, renal dysfunction and systemic inflammation.

Hospitalización diurna como modelo de atención de salud en pacientes adultos inmunocompetentes con neumonía adquirida en la comunidad / Respiratory day hospital care for immunocompetent adult patients with community-acquired pneumonia

Background: Day hospitals can reduce health care costs without increasing the risks of patients with lower respiratory tract infection. Aim: To report the experience of a respiratory day hospital care delivered to adult patients with community-acquired pneumonia (CAP) in a public hospital. Material and Methods: During the fall and winter of 2011 and 2012, adult patients with CAP of intermediate risk categories were assessed in the emergency room, their severity was stratified according to confusion, respiratory rate, blood pressure, 65 years of age or older (CRB-65) score and the Chilean CAP Clinical Guidelines, and were admitted to the respiratory day hospital. Results: One hundred seventeen patients aged 67 ± 16 years, (62% females) with CAP were attended in the respiratory day hospital. Ninety percent had comorbidities, especially chronic obstructive pulmonary disease in 58%, heart disease in 32%, diabetes in 16% and asthma in 13%. Their most important risk factors were age over 65 years in 60%, comorbidities in 88%, failure of antibiotic treatment in 17%, loss of autonomy in 21%, vital sign abnormalities in 60%, mental confusion in 5%, multilobar CAP in 23%, pleural effusion in 15%, hypoxemia in 41% and a serum urea nitrogen over 30 mg/dL in 16%. Patients stayed an average of seven days in the day hospital with oxygen, hydration, chest physiotherapy and third-generation cephalosporins (89%) associated with quinolones (52%) or macrolides (4%). Thirteen patients required noninvasive ventilation, eight patients were hospitalized because of clinical deterioration and three died in hospital. Conclusions: Day hospital care reduced hospital admission rates of patients with lower respiratory tract infections.

Factores pronósticos y sobrevida a mediano plazo de una cohorte de pacientes con cáncer pulmonar atendidos en la red de salud de la Universidad Católica: Período 2007-2011 / Prognostic factors and short-term survival of a cohort of adult patients with lung cancer treated in a network of health, 2007-2011

Lung cancer is the leading cause of death from malignancy worldwide. In Chile the magnitude of the problem and the diagnosis-associated survival are unknown. Methods: We examined a cohort of 202 adult patients with lung cancer histologically confirmed in a single health network between January 2007 and December 2011. We accessed to medical records and images files of patients, recording the clinical, histological, imaging and staging data. Patients were followed until December 2013 to assess survival. Results: The mean age of the cohort was 68.1 ± 11.5 years, 53% were male and 86% had a smoking history. 82.2% of the cases were symptomatic at diagnosis, been cough the symptom most frequently reported. The predominant histological subtype was adenocarcinoma (42%), followed by squamous cell carcinoma (26.2%). In women, adenocarcinoma was the leading histology variety (56.4%), and in males it was adenocarcinoma (37%) and squamous cell carcinoma (33.3%). The majority of the patients were diagnosed at advanced stages of the disease. The 36-month survival rate was 46.1%. The mean survival according to clinical stage was 70.7 month in stage I, 60.3 in stage II, 47.1 in IIIA, 12.3 in IIIB and 11.7 month in stage IV. According to histological variety, the mean survival was 36.6 month in adenocarcinoma, 33.8 in squamous cell carcinoma, 20.9 in large-cell carcinoma, 11.9 in small-cell carcinoma and 19.6 month in undifferentiated non small-cell carcinoma. There were no significant differences in survival by age or gender. Conclusion: The most common histological type was adenocarcinoma and short-term survival was related to the clinical staging and histological variants.

El cáncer pulmonar es la principal causa de muerte por neoplasia a nivel mundial. En Chile se desconoce la magnitud del problema y la sobrevida asociada al diagnóstico. Material y Métodos: Se examinó una cohorte de 202 pacientes adultos con cáncer pulmonar confirmados histopatológicamente en una red de salud entre Enero de 2007 y Diciembre de 2011. Se accedió a las fichas clínicas y archivos de imágenes de los pacientes, registrando las variables clínicas, histológicas, imagenológicas y la etapificación clínica. Se siguió prospectivamente a los pacientes hasta Diciembre de 2013 para determinar sobrevida. Resultados: La edad promedio de la cohorte fue de 68,1 ± 11,5 años, 53% eran varones y 86% tenía historia de tabaquismo. El 82,2% de los casos presentaron síntomas al momento del diagnóstico, siendo la tos el más frecuente. La variedad histológica preponderante fue el adenocarcinoma (42%), seguido del carcinoma escamoso (26,2%). En las mujeres la mayoría de los tumores correspondieron a adenocarcinomas (56,4% del total) y en varones predominaron el adenocarcinoma (37%) y el carcinoma escamoso (33,3%). La mayoría de los pacientes se diagnosticaron en estadios avanzados de la enfermedad. La sobrevida global a los 36 meses fue 46,1%. La sobrevida media por estadio clínico fue de 70,7 meses en el estadio I, 60,3 meses en estadio II, 47,1 meses en IIIA, 12,3 meses en IIIB y 11,7 meses en IV Según histología, la sobrevida media en meses fue de 36,6 en adenocarcinoma, 33,8 en carcinoma escamoso, 20,9 en células grandes, 11,9 en células pequeñas y 19,6 en tumor no células pequeñas indiferenciado. No hubo diferencias significativas en la sobrevida por edad y género. Conclusión: La variedad histológica más frecuente es el adenocarcinoma y la sobrevida está relacionada a la etapificación clínica y variedad histológica.

Evaluación de los músculos respiratorios en la parálisis diafragmática bilateral / Assessment of respiratory muscle strength in bilateral diaphragmatic paralysis

Measurement of respiratory muscle strength is useful in order to detect respiratory muscle weakness and to quantify its severity. Apropos of a patient with bilateral diaphragmatic paralysis, we review the clinical manifestations and methods for assessing the strength of the respiratory muscles. In patients with severe respiratory muscle weakness, vital capacity and total lung capacity are reduced but are a non-specific and relatively insensitive measure. Conventionally, inspiratory and expiratory muscle strength has been assessed by maximal inspiratory and expiratory mouth pressures sustained for one second (PIMax and PEMax). The sniffmanoeuvre is natural and probably easier to perform. Sniff pressures are more reproducible and useful measure of diaphragmatic strength. However, the PIMax-PEMax and sniff manoeuvres are volition dependent, and submaximal efforts are most likely to occur in patients who are ill or breathless. Non-volitional tests include measurements of twitch esophageal, gastric and transdiaphragmatic pressure during bilateral electrical and magnetic phrenic nerve stimulation. Electrical phrenic nerve stimulation is technically difficult and is also uncomfortable and painful. Magnetic phrenic nerve stimulation is less painful and transdiaphragmatic pressure is reproducible in normal subjects. Systematic clinical evaluation and additional laboratory tests allow the diagnosis in most patients with respiratory muscle weakness.

La evaluación de la fuerza de los músculos respiratorios permite diagnosticar y cuantificar la gravedad de la debilidad muscular en diferentes enfermedades. A propósito de un paciente con parálisis diafragmática bilateral, hemos revisado el cuadro clínico y los procedimientos diagnósticos para evaluar la fuerza de los músculos respiratorios. En los pacientes con debilidad muscular respiratoria severa, disminuye la capacidad vital y la capacidad pulmonar total, pero es una medida inespecífica y relativamente insensible. Tradicionalmente, la fuerza muscular respiratoria es evaluada midiendo la presión inspiratoria y espiratoria máximas en la boca sostenidas durante un segundo (PIMax y PEMax). La medición de la presión inspiratoria máxima en la nariz (SNIP) es una maniobra natural, más simple de medir y más reproducible, siendo útil en la evaluación de la fuerza diafragmática. Sin embargo, estas técnicas no invasivas son operador dependiente, por lo tanto, esfuerzos submáximos es más probable que ocurran en pacientes graves o con disnea. Las mediciones de las presiones esofágica, gástrica y transdiafragmática mediante estimulación eléctrica o magnética del nervio frénico no son dependientes de la voluntad y son más confiables. Sin embargo, la estimulación eléctrica del nervio frénico es técnicamente difícil y puede ser incómoda y dolorosa. La estimulación magnética del nervio frénico es menos dolorosa y la medición de la presión transdiafragmática es reproducible en sujetos normales. La evaluación clínica sistemática y los exámenes de laboratorio complementarios permiten establecer el diagnóstico en la mayoría de los pacientes con debilidad de los músculos respiratorios.

Caracterización de las infecciones respiratorias en pacientes adultos oncológicos / Clinical characteristics of respiratory infections in patients with cancer

Introduction: Infections are common in oncology. Aim: To characterize respiratory infections in hospitalized adult cancer patients. Methods: Prospective, descriptive study of febrile adult patients in oncology at the Hospital Clínico Universidad Católica de Chile, between April 2008 and April 2009. Results: 187 episodes were evaluated. Clinical infection was recognized in 70% and 33 episodes (25%) were respiratory focus. Neoplastic disease corresponded to solid organ cancer in 77% of cases and 33% were admitted with febrile neutropenia. The upper respiratory tract infection accounted for 36% and low respiratory tract infection 65% of cases; 55% was pneumonia. Etiology of these was isolated in 39% (S. pneumoniae 2 cases, S. bovis 1, E. faecalis 1, P. jirovecii 2, S. maltophilia 1 and A. fumigatus 1). Hospital mortality for pneumonia was 22% and overall mortality 12%. Conclusions: Respiratory infections are a major focus in adult cancer patients, highlighting pneumonia. It carries high mortality and varied etiology.

Introducción: Las infecciones en oncología son frecuentes. Objetivo: Caracterizar las infecciones respiratorias en pacientes oncológicos hospitalizados. Métodos: Estudio descriptivo prospectivo de pacientes adultos oncológicos febriles en el Hospital Clínico de la Universidad Católica, entre abril de 2008 y abril de 2009. Resultados: Se evaluaron 187 episodios. Se identificó foco clínico en 70% y 33 episodios (25%) correspondieron a foco respiratorio. La patología oncológica correspondió a tumores de órgano sólido en 77% de los casos y el 33% ingresó con neutropenia febril. La infección respiratoria alta representó el 36% y baja un 65% de los casos; 55% fueron neumonía. De estos, se aisló el agente causal en un 39% (S. pneumoniae 2 casos, S. bovis 1, E. faecalis 1, P. jirovecii 2, S. maltophilia 1 y A. fumigatus 1). La letalidad en el hospital por neumonía fue 22% y la mortalidad general 12%. Conclusiones: La infección respiratoria es un motivo de consulta y hospitalización frecuente en pacientes oncológicos, destacando la neumonía. Conlleva elevada mortalidad y etiología variada.

Consultas ambulatorias pediátricas atendidas en el servicio de urgencia de un hospital universitario / Pediatric outpatient consultation at the emergency department of a university hospital

Introducción: Conocer el perfil epidemiológico de las consultas pediátricas atendidas en el servicio de urgencia (SU) es esencial para planificar los procesos de atención médica y orientar los programas de educación e investigación. Objetivos: Describir las características de la población infantil y los principales motivos de consulta (MC) atendidos en un SU pediátrico. Pacientes y Método: Estudio clínico descriptivo retrospectivo de las visitas realizadas a un SU infantil en un hospital académico de Santiago durante un período de doce meses. Se analizaron los MC por grupo etario, gravedad, estacionalidad, forma de egreso y frecuencia de visitas recurrentes. Resultados: Se evaluaron 24.531 consultas pediátricas, 51,9 por ciento (n = 12.720) eran varones. La edad de los pacientes osciló entre un día y 15 años, con una mediana de 36,5 meses. El 1,5 por ciento de los pacientes (n = 362) eran recién nacidos (RN), 17,6 por ciento (n = 4.326) lactantes, 51,9 por ciento (n = 12.725) preescolares y 29 por ciento (n = 7.118) escolares. Los principales MC fueron fiebre (n = 6.643, 28,2 por ciento), síntomas gastrointestinales (n = 5.606, 23,8 por ciento) y síntomas respiratorios (n = 5.018, 21,3 por ciento), los cuales no difirieron significativamente según género. La mayoría de los pacientes (95,5 por ciento) fueron enviados a su domicilio. El riesgo de hospitalización fue más elevado en los RN y en aquellos que consultaron por ictericia (OR = 7,20; IC 95 por ciento 3,12-16,6), síntomas neurológicos (OR = 6,90; IC 95 por ciento 4,60-10,4) e intoxicaciones (OR = 6,45; IC 95 por ciento 2,82-14,7). Alrededor del 4 por ciento fueron consultas repetidas, especialmente en los RN. Conclusiones: El perfil epidemiológico de las consultas pediátricas atendidas en el SU fue similar al descrito en estudios internacionales. Sin embargo, encontramos una menor tasa de hospitalización a pesar que los pacientes presentaban un perfil de riesgo similar en la admisión al SU.

Introduction: To determine the epidemiological profile of pediatric consultations treated at the emergency department (ED) is essential for planning processes of medical care and to guide education programs and research. Objectives: To describe the characteristics of the child population and the main reasons for consultation (RFC) seen in a pediatric emergency service. Patients and Method: A retrospective, descriptive clinical study was conducted regarding the visits to the Children's Emergency Service of an academic hospital in Santiago, for a period of twelve months. RFC were analyzed by age group, severity, seasonality, disposition and frequency of recurrent visits. Results: 24,531 pediatric consultations were evaluated, 51.9 percent were male (n = 12,720). The age of the patients ranged between one day old and 15 years, with a median age of 36.5 months. 1.5 percent of patients were newborns (NB), 17.6 percent were infants (n = 4,326), 51.9 percent were preschoolers (n = 12,725) and 29 percent were school children (n = 7,118). Major RFC were fever (n = 6,643, 28.2 percent), gastrointestinal symptoms (n = 5,606, 23.8 percent) and respiratory symptoms (n = 5,018, 21.3 percent), which did not differ significantly according to gender. Most patients (95.5 percent) were sent to their homes. The risk of hospitalization was more elevated in NB and in those with jaundice (OR = 7.20, 95 percent CI 3.12 to 16.6), neurological symptoms (OR = 6.90, 95 percent CI 4.60 -10.4) and poisoning (OR = 6.45, 95 percent CI 2.82 to 14.7). About 4 percent were repeat visits, especially in the NB group. Conclusions: The epidemiological profile of pediatric consultations seen at the ED was similar to that described in previous studies. However, a lower rate of hospitalization was found even though the patients had similar risk profile.

Infección pulmonar por mycobacterium avium complex en el huésped inmunocompetente / Mycobacterium avium complex pulmonary disease in immunocompetent adult patients

Las micobacterias no tuberculosas (MNT) se reconocen cada vez más como importantes patógenos pulmonares. El complejo Mycobacterium avium-intracellulare (MAC) causa la mayoría de las infecciones pulmonares por MNT. Aunque el organismo fue identificado en la década de 1890, su potencial patogenicidad en seres humanos fue reconocida sólo cincuenta años después. Los pacientes con enfermedad pulmonar preexistente o inmunodeficiencia están en mayor riesgo de desarrollar infección por MAC. Sin embargo, la mayoría de los casos se producen en mujeres de edad avanzada inmunocompetentes en asociación con infiltrados nodulares y bronquiectasias. Recientemente, la enfermedad pulmonar también se ha descrito en pacientes inmunocompetentes expuestos a equipos de hidroterapia o jacuzzis contaminados con MAC. En relación a dos pacientes adultos inmunocompetentes con enfermedad pulmonar por MAC examinamos el cuadro clínico, los criterios diagnósticos y el tratamiento de esta entidad.

Nontuberculous mycobacteria (NTM) are increasingly recognized as important pulmonary pathogens. Mycobacterium avium intracellulare complex (MAC) causes most lung infections due to NTM. Although the organism was identified in the 1890s, its potential to cause human disease was only recognized 50 years later. Patients with preexisting lung disease or immunodeficiency are at greatest risk for developing MAC infection. The majority of MAC pulmonary cases, however, occur in immunocompetent elderly women in association with nodular infiltrates and bronchiectasis. More recently, pulmonary disease has also been described in immunocompetent patients after exposure to MAC-contaminated hot tubs. We describe two cases of MAC lung disease in immunocompetent adult patients without preexisting lung disease and we review clinical manifestations, diagnostic criteria and treatment of this entity.

Sobrevida a largo plazo en adultos inmunocompetentes mayores de 60 años hospitalizados por neumonía adquirida en la comunidad / Long-term survival of immunocompetent patients older than 60 years hospitalized for community-acquired pneumonia

Background: A reduction in long-term survival of adult patients hospitalized with community-acquired pneumonia (CAP), especially older people with múltiple comorbidities, has been reported. Aim: To examine the clinical variables associated to mortality at 72 months of adult patients older than 60 years hospitalized with CAP and compare their mortality with a control group matched for age, gender and place of admission. Material and Methods: Prospective assessment of 465 immunocompetent patients aged 61 to 101 years, hospitalized for CAP in a teaching hospital. Hospital and 30 day mortality was obtained from medical records. Seventy two months survival ofthe 424 patients who were discharged olive, was compared with a group of 851 patients without pneumonia paired for gender and age. Mortality at 72 months was obtained from death certificates. Results: Eighty seven percent of patients had comorbidity. The median hospital length ofstay was 10 days, 8.8% died in the hospital, 29.7% at one year follow-up and 61.9%o at 6 years. The actuarial survival at six years was similar in the cohort of adults hospitalized with CAP and the control group matched for age, gender and site of care. In a multivariate analysis, the clinical variables associated with increased risk of dying during long-term follow-up were older age, chronic cardiovascular and neurological diseases, malignancy, absence of fever, low C-reactive protein at hospital admission and high-risk parameters of the Fine índex. Conclusions: Advanced age, some specific comorbidities, poor systemic inflammatory response at admission and high risk parameters of the Fine Index were associated to increased risk of dying on long-term follow-up among older adults hospitalized for CAP.

Predictores clínicos de mortalidad en el seguimiento a mediano plazo en pacientes adultos inmunocompetentes hospitalizados por neumonía adquirida en la comunidad / Predictors of one year mortality among immunocompetent adults hospitalized for community-acquired pneumonia

Background: Mortality increases in adults, especially in older adults, after recovery from an episode of community-acquired pneumonia (CAP). Aim: To analyze survival and predictors of death at one year follow up of a cohort of adult patients hospitalized with CAP. Material and Methods: Immunocompetent patients admitted to a clinical hospital for an episode of CAP were included in the study and were assessed according to a standardized protocol. One year mortality after admission was assessed using death records of the National Identification Service. Clinical and laboratory variables measured at hospital admission associated with risk of death at one year follow up were subjected to univariate and multivariate analysis by a logistic regression model. Results: We evaluated 659 patients aged 68 ± 19 years, 52% were male, 77% had underlying conditions (especially cardiovascular, neurological and respiratory diseases). Mean hospital length of stay was 9 days, 7.1% died during hospital stay and 15.8% did so during the year of follow-up. A causal agent was identified in one third of cases. The main pathogens isolated were Streptococcus pneumoniae (12.9%), Haemophilus influenzae (4.1%), respiratory viruses (6.5%) and Gram-negative bacilli (6.5%). In multivariate analysis, the clinical variables associated with increased risk of dying during the year of follow-up were older age, chronic neurological disease, malignancies, lack of fever at admission and prolonged hospital length of stay. Conclusions: Age, specific co-morbidities such as chronic neurological disease and cancer, absence of fever at hospital admission and prolonged hospital length of stay were associated with increased risk of dying during the year after admission among adult patients hospitalized with community-acquired pneumonia.

Evaluación de un módulo de docencia ambulatoria de enfermedades respiratorias en el currículo de pregrado de Medicina / Evaluation of a teaching ambulatory module of respiratory diseases in the undergraduate medical curriculum

Background: As the focus of healthcare provision shifts towards ambulatory care, increasing attention must now be given to develop opportunities for clinical teaching in this setting. Aim: To assess teacher and students' views about the strengths and weaknesses of real and simulated patient interactions for teaching undergraduate students clinical skills in the ambulatory setting. Material and Methods: Fourth-year medical students were exposed in a systematic way, during two weeks, to real and simulated patients in an outpatient clinic, who presented common respiratory problems, such as asthma, chronic obstructive pulmonary disease, smoking and sleep apnea syndrome. After the clinical interview, students received feedback from the tutor and their peers. The module was assessed interviewing the teachers and evaluating the results qualitatively. Students evaluated the contents and quality of teaching at the end of the rotation. Results: Tutors identified the factors that facilitate ambulatory teaching. These depended on the module design, resources and patient care, of characteristics of students and their participation, leadership and interaction with professors. They also identified factors that hamper teaching activities such as availability of resources, student motivation and academic recognition. Most students evaluated favorably the interaction with real and simulated patients in the ambulatory setting. Conclusions: Teaching in the ambulatory setting was well evaluated by students and teachers. The use of qualitative methodology allowed contrasting the opinions of teachers and students.

Etiología y biomarcadores de inflamación sistémica en las exacerbaciones leves a moderadas de la enfermedad pulmonar obstructiva crónica / Etiology and biomarkers of systemic inflammation in mild to moderate COPD exacerbations

Background: The etiology of acute exacerbations of chronic obstructive pulmonary disease (COPD) is heterogeneous and still under discussion. Inflammation increases during exacerbation of COPD. The identification of inflammatory changes will increase our knowledge and potentially guide therapy. Aim: To identify which inflammatory parameters increase during COPD exacerbations compared to stable disease, and to compare bacterial and viral exacerbations. Material and Methods: In 85 COPD patients (45 males, mean age 68 ± 8 years, FEV1 46 ± 17% of predicted) sputum, nasopharyngeal swabs and blood samples were collected to identify the causative organism, during a mild to moderate exacerbation. Serum ultrasensitive C reactive protein (CRP), fibrinogen and interleukin 6 (IL 6), neutrophil and leukocyte counts were measured in stable conditions, during a COPD exacerbation, 15 and 30 days post exacerbation. Results: A total of 120 mild to moderate COPD exacerbations were included. In 74 (61.7%), a microbial etiology could be identified, most commonly Mycoplasma pneumoniae (15.8%), Rhinovirus (15%), Haemophilus influenzae (14.2%), Chlamydia pneumoniae (11.7%), Streptococcus pneumoniae (5.8%) and Gram negative bacilli (5.8%). Serum CRP, fibrinogen and IL 6, and neutrophil and leukocyte counts significantly increased during exacerbation and recovered at 30 days post exacerbation. Compared to viral exacerbations, bacterial aggravations were associated with a systemic inflammation of higher magnitude. Conclusions: Biomarkers of systemic inflammation increase during mild to moderate COPD exacerbations. The increase in systemic inflammation seems to be limited to exacerbations caused by bacterial infections.

Metodología de adaptación de una guía clínica para el manejo de pacientes adultos con neumonía adquirida en la comunidad en una red de salud privada / The adaptation methodology of a guideline for the management of adults with community-acquired pneumonia

Background: Clinical practice guidelines (CPG) are widely used as tools for improving quality of health care. Guidelines developed elsewhere, can be adapted using a valid and systematic process. Aim: To describe the methodology used in the process of adaptation of a guideline for the management of adults with community-acquired pneumonia (CAP) in a private health care organization. Material and Methods: We used the ADAPTE framework involving three main phases. At the set-up phase a guideline adaptation group integrated by medical specialists from different disciplines, a methodologist and a nurse coordinator was formed. At the adaptation phase, the specific clinical questions to be addressed by the guidelines were identified. Results: Twenty five guidelines were initially retrieved. After their assessment, the number was reduced to only three. Recommendations from these guidelines were 'mapped' and focused searches were carried out where 'evidence gaps' were identified. An initial draft was written and revised by the adaptation group. At the finalization phase, the external review of the guideline was carried out and a process for the regular review and update of the adapted guideline was defined. Conclusions: We developed a guideline for the management of adults with CAP, adapted to the local context of our health care system, using guidelines developed elsewhere. This guideline creation method can be an efficient means of saving professional resources.

Evaluación clínico-radiológica y clasificación de la bronquiolitis del adulto / Bronchiolar disorders: clinical-radiological assessment and classification

Bronchiolar disorders are generally difficult to diagnose. A detailed clinical history may point toward a specific diagnosis. Pertinent clinical questions include history of smoking, collagen vascular disease, inhalation injury, medication use and organ transplantation. It is important also to evaluate possible systemic and pulmonary signs of infection, evidence of air trapping, and high-pitched expiratory wheezing, which may suggest small airways involvement. Pulmonary function tests and plain chest radiography may demonstrate abnormalities; however, they rarely prove sufficiently specific to obviate bronchoscopic or surgical biopsy. High-resolution CT (HRCT) scanning of the chest is often an important diagnostic tool to guide diagnosis in these difficult cases, because different subtypes of bronchiolar disorders may present with characteristic image findings. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Primary bronchiolar disorders include acute bronchiolitis, respiratory bronchiolitis, follicular bronchiolitis, mineral dust airway disease, constrictive bronchiolitis, diffuse panbronchiolitis, and other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, collagen vascular disease, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia, and pulmonary Langerhans’ cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical and prognostic significance of a bronchiolar lesion is best determined by identifying the etiology, underlying histopathologic pattern and assessing the correlative clinic-physiologic-radiologic context.

Índices predictores de eventos adversos en el adulto inmunocompetente hospitalizado por neumonía neumocóccica adquirida en la comunidad / Severity scores for predicting clinically relevant outcomes for immunocompetent adult patients hospitalized with community-acquired pneumococcal pneumonia

Streptococcus pneumoniae is the main cause of community-acquired pneumonia (CAP) in adults. Objectives: To compare accuracy and discriminatory power of three validated rules for predicting clinically relevant adverse outcomes in patients hospitalized with community-acquired pneumococcal pneumonia. Measurements: We pros-pectively compared the pneumonia severity index (PSI), British Thoracic Society score (CURB-65) and severe CAP score (SCAP) in a cohort of 151 consecutive immunocompetent adult patients hospitalized with pneumo-coccal pneumonia. Major adverse outcomes were admission to ICU, need for mechanical ventilation, in-hospital complications and 30-day mortality. Mean hospital length of stay (LOS) was also evaluated. The predictive indexes were compared based on sensitivity, specificity, and area under the curve of the receiver operating characteristic. Results: The mean age of 151 immunocompetent adult patients hospitalized with pneumococcal pneumonia was 64 years (range, 16 to 92); 58 percent were male, 75 percent had comorbidities, 26 percent were admitted to the intensive care unit and 9 percent needed mechanical ventilation. The rate of all adverse outcomes and hospital LOS increased directly with increasing PSI, CURB-65 and SCAP scores. The three severity scores allowed us to predict the risk of in-hospital complications and 30-day mortality. The PSI score was more sensitive and the SCAP was more specific to predict in-hospital complications and the risk of death. However, the SCAP was more sensitive and specific in predicting the use of mechanical ventilation. Conclusion: The severity scores validated in the literature allow us to predict the risk of complications and death in adult patients hospitalized with pneumococcal pneumonia. Nevertheless, the clinical indexes differ in their sensitivity, specificity and discriminatory power to predict different adverse events.

Streptococcus pneumoniae es el principal agente causal de la neumonía adquirida en la comunidad. Objetivos: Examinar el poder discriminativo de tres índices pronósticos en la predicción de eventos adversos clínicamente relevantes en pacientes hospitalizados por neumonía neumocóccica adquirida en la comunidad. Métodos: Evaluamos el índice de gravedad de la neumonía (IGN), CURB-65 y el índice de neumonía grave adquirida en la comunidad (INGAC) en una cohorte de 151 adultos inmunocompetentes hospitalizados por neumonía neu-mocóccica. Los eventos adversos examinados fueron la admisión a UCI, necesidad de ventilación mecánica, complicaciones en el hospital y mortalidad a 30 días. Las reglas predictoras fueron comparadas en base a su sensibilidad, especificidad y área bajo la curva receptor operador. Resultados: Se evaluaron 151 pacientes (64 ± 18 años), 58 por ciento varones, 75 por ciento tenía co-morbilidad, 26 por ciento fueron admitidos a la UCI y 9 por ciento requirieron ventilación mecánica. La tasa de eventos adversos fue más elevada y la estadía en el hospital más prolongada en las categorías de alto riesgo de los tres índices predictores. Los tres índices permitieron, a su vez, predecir el riesgo de complicaciones y muerte en el seguimiento a 30 días. El IGN fue más sensible y el INGAC más específico en la pesquisa de complicaciones en el hospital y en predecir el riesgo de muerte. El INGAC fue más sensible y específico en predecir el uso de ventilación mecánica. El CURB-65 tuvo menor poder discriminatorio comparado con el IGN e INGAC. Conclusión: Los índices pronósticos validados en la literatura médica permiten predecir el riesgo de complicaciones y muerte en el adulto hospitalizado por neumonía neumocóccica. Sin embargo, difieren en su sensibilidad, especificidad y poder discriminatorio de los distintos eventos adversos.