Análisis bibliométrico de la producción científica cubana sobre asma en Scopus

Introducción: El asma es una entidad con alta prevalencia a nivel mundial y en Cuba, que ha suscitado nuevas investigaciones. Objetivo: Caracterizar la producción científica cubana sobre asma en la base de datos Scopus. Materiales y métodos: Se realizó un estudio observacional, descriptivo y bibliométrico de los artículos publicados sobre asma en Scopus con autores cubanos, desde 1973 hasta 2021. Para la recuperación de los registros se empleó una fórmula de búsqueda. Para el análisis de los datos se usaron los software Bibexcel y VOSviewer. Resultados: Se publicaron 154 investigaciones sobre asma, con predominio de artículos originales (136) y de revisión (12). Las áreas más productivas fueron Medicina (144) e Inmunología y Microbiología (34). Los artículos fueron publicados en 48 revistas; de ellas, 11 fueron cubanas, con la Revista Cubana de Medicina como la más productiva. México aportó el mayor número de colaboraciones (10). El Hospital Clínico Quirúrgico Docente General Calixto García (15) fue el más productivo. Se identificaron tres clústeres de palabras clave, con "human", "asthma" y "Cuban" como términos centrales y de mayor ocurrencia. Conclusiones: Existió una baja producción científica sobre asma, centrada principalmente en artículos originales, en el área de Medicina y en revistas nacionales. Se evidenció colaboración internacional. Los ejes principales de investigación fueron el diagnóstico, tratamiento, investigación básica en modelos animales, nuevas terapéuticas, factores de riesgo y prevención.

Introduction: Asthma is an entity with high prevalence worldwide and in Cuba, which has prompted new research. Objective: To characterize Cuban scientific production on asthma in the Scopus database. Materials and methods: An observational, descriptive and bibliometric study was carried out on articles on asthma published in Scopus by Cuban authors, from 1973 to 2021. A search formula was used to retrieve the records. Bibexcel and VOSviewer were used for data analysis. Results: 154 research papers on asthma were published; with a predominance of original (136) and review articles (12). The most productive areas were Medicine (144) and Immunology and Microbiology (34). Articles were published in 48 journals, of which 11 were Cuban, with the Revista Cubana de Medicina (Cuban Journal of Medicine) being the most productive. Mexico contributed the highest number of collaborations (10). The Teaching Hospital General Calixto García (15) was the most productive. 3 key word clusters were identified, with "human", "asthma" and "Cuban" as central and most occurring terms. Conclusions: There was a low scientific production on asthma, mainly focused on original articles, in the area of Medicine and in national journals. International collaboration was evident. The main areas of research were diagnosis, treatment, basic research in animal models, new therapeutics, risk factors and prevention.

Reactive airways dysfunction syndrome following inhalation of hydrogen chloride vapor

Hydrogen chloride is available commercially as an anhydrous gas or an aqueous solution, hydrochloric acid. Exposure to this gas has been associated with the development of reactive airways dysfunction syndrome. However, there are few published reports. A 37-year-old woman developed progressive bronchospasm and acute respiratory failure after cleaning an enclosed space with an unknown concentration of hydrochloric acid gas from a cleaning substance. She had no prior history of asthma or atopy. Severe bronchospasm developed, leading to hypoxemia and diffuse interstitial infiltrates, necessitating orotracheal intubation and admission to the intensive care unit. Asthma-like symptoms such as cough, wheezing, and dyspnea; requiring bronchodilators, and repeated hospitalizations are persistent a year after the accident. Pulmonary function testing showed mild airflow obstruction.

Risk Factors and Comorbidities Associated With the Allergic Rhinitis Phenotype in Children According to the ARIA Classification

PURPOSE: Data are lacking on the association between the allergic rhinitis (AR) phenotype and sensitization to specific allergens or bronchial hyperresponsiveness (BHR) in children. We here investigated risk factors and comorbidities, including sensitization to specific allergens and BHR, for the AR phenotype by AR and its Impact on Asthma (ARIA) classification in a general population-based birth cohort study. METHODS: We enrolled 606 children aged 7 years from the Panel Study of Korean Children. The AR phenotype was assigned in accordance with the ARIA classification in children. Skin prick tests and Provocholine provocation test were performed. Risk factors and comorbidities for AR phenotypes were then analyzed. RESULTS: The prevalence of mild and moderate to severe AR in our study cohort was 37.2% and 8.8%, respectively. Recent use of analgesics or antipyretics and current cat ownership were associated with the risk of mild persistent AR. Sensitizations to Dermatophagoides Pteronyssinus (Der p), Japanese hop and cat were associated with moderate to severe persistent AR. Children with moderate to severe AR had a higher risk of current asthma and BHR compared to mild AR cases (adjusted odds ratio [aOR], 5.26; 95% confidence interval [CI], 1.77–15.62). Moderate to severe AR with allergic sensitization was associated with the highest risk of BHR (aOR, 11.77; 95% CI, 3.40–40.74). CONCLUSIONS: Moderate to severe-persistent AR is more closely related to respiratory comorbidities and sensitizations than mild AR. Stratifying the AR phenotype by ARIA classification may assist in disease management.

Bronchial Response to High and Low Molecular Weight Occupational Inhalant Allergens

PURPOSE: Occupational asthma may be induced by high- or low-molecular weight allergens (HMWA or LMWA, respectively). The study was conducted to compare the pattern of bronchial response in 200 HMWA-induced asthmatics (n = 130) and LMWA-induced asthmatics (n = 70). METHODS: The study participants underwent a single-blind, placebo-controlled specific inhalation challenge (SIC) with workplace allergens, accompanied by evaluation of non-specific bronchial hyperresponsiveness (NSBHR) with methacholine before and after the SIC. RESULTS: A single early bronchial response more frequently occurred in HMWA-induced asthmatics than in LMWA-induced asthmatics (86.2% vs. 20%). An isolated late bronchial response or atypical patterns were more frequently observed in LMWA-induced asthmatics than in LMWA-induced asthmatics (45.7% vs. 3.8% or 34.3% vs. 10%, respectively). Baseline NSBHR before SIC was more often detected in LMWA-induced asthmatics than in HMWA-induced asthmatics (81.4% vs. 54.6%), and the median value of the provocation concentration of methacholine was relevantly lower in these patients before and after SIC. A significant 3-fold increase in NSBHR after SIC was observed more often in LMWA-induced asthmatics than in HMWA-induced asthmatics (82.8% vs. 66.1%). In addition, compared to LMWA-induced asthmatics, HMWA-induced asthmatics were older, were more frequently active smokers, showed lower level of NSBHR, and more frequently continued their work in harmful occupational exposure. CONCLUSIONS: The results of this study suggest that HMWA-induced asthmatics may have milder clinical courses and that there is a possibility of job continuation despite asthma exacerbation requiring medical surveillance.

Actualización de la prueba de provocación bronquial con ejercicio (PPBE) / Update of the bronchial provocation test with exercise

The bronchial challenge test with exercise aims to demonstrate the presence of exercise-induced bronchial hyperreactivity, characteristic of bronchial asthma. Its realization is well standardized, requiring special environmental conditions, preparation and submaximum effort of the patient. The response is measured by spirometry, and it is considered a positive exercise test a drop in the expired volume at the first second (FEV1) of 10%. This article describes the elements necessary to facilitate this exam, according to national and international standards and guidelines.

La prueba de provocación bronquial con ejercicio tiene como objetivo demostrar la presencia de hiperreactividad bronquial inducida por ejercicio, característica del asma bronquial. Su realización está bien estandarizada, requiriendo de condiciones ambientales especiales, preparación y esfuerzo submáximo del paciente. La respuesta se mide mediante espirometría, y se considera una prueba de provocación con ejercicio positivo, a una caída del volumen espirado al primer segundo (VEF1) del 10%. En este artículo se describen los elementos necesarios para facilitar la realización de este examen, acorde a normas y guías nacionales e internacionales.

Actualización en la prueba de provocación bronquial con metacolina en el niño / Update in the bronchial challenge test with methacholine in children

This document updates the recommendations of the bronchial challenge test with methacholine in children. It is based primarily on the recommendations contained in the guide on the technical standard of the bronchial challenge test for methacholine from the European Society of Respiratory Diseases. The main change is the recommendation to use PD20 (methacholine dose that causes a 20% drop in FEV1) instead of PC20 (methacholine concentration that causes a 20% drop in FEV1), which allows for comparable results when different devices and different protocols are used.

Este documento actualiza las recomendaciones de la prueba de provocación bronquial con metacolina en niños. Se basa fundamentalmente en las recomendaciones contenidas en la guía sobre el estándar técnico de la prueba de provocación bronquial de metacolina de la Sociedad Europea de Enfermedades Respiratorias. El principal cambio es la recomendación de utilizar la PD20 (dosis de metacolina que provoca una caída de 20% del VEF1) en vez de PC20 (concentración de metacolina que provoca una caída del 20% en el VEF1), lo cual permite tener resultados comparables cuando se usan diferentes dispositivos y diferentes protocolos.

Effects of neonatal Streptococcus pneumoniae pneumonia on airway epithelial injury of mice / 解放军医学杂志

Objective To investigate the effects of neonatal Streptococcus pneumoniae pneumonia (S.pp) on airway epithelial injury of mice. Methods Neonatal C57BL/6 (1-week-old) mice were infected intranasally with 2×105 cfu of Streptococcus pneumoniae (S.p) in a volume of 5 μl sterile phosphate buffered saline (PBS) (S.pp group), while the mock-infected controls received the same volume of sterile PBS (control group). Five weeks after the infection, the airway hyperresponsiveness (AHR) was evaluated by invasive body plethysmography system. The lung tissue was harvested, CDH1 and TJP1 mRNA levels were analyzed by RT-PCR. Immunohistochemical method and Western blotting were used to evaluate the expressions of E-cadherin and tight junction protein (ZO-1). Airway inflammation was detected by HE staining, the subcutaneous collagen deposition beneath the airway epithelium was evaluated by Masson staining, and the number of goblet cells was detected by Alcian Blue Periodic Acid Schiff (AB-PAS) staining. Results When the concentration of aerosolized methacholine inhaled by mice ranged from 6.25 to 50 mg/ml, the AHR was obviously higher in S.pp group than that in control group (P<0.001); the levels of CDH1 and TJP1 mRNA in the lung tissue were markedly lower in S.pp group (0.85±0.29 and 0.43±0.16) than those in control group (0.85±0.29 vs. 1.42±0.40, P=0.033; 0.43±0.16 vs. 0.83±0.26, P=0.010, respectively); the expression levels of E-cadherin and ZO-1 in airway epithelium were lower in S.pp group than those in control group (9.66±4.89 vs. 24.52±7.58, P=0.001; 13.54±3.79 vs. 25.53±5.99, P=0.005, respectively); the protein levels of E-cadherin and ZO-1 in lung tissue were remarkably lower in S.pp group than those in control group (0.23±0.06 vs. 0.38±0.06, P=0.019; 0.68±0.12 vs. 0.96±0.16, P=0.032, respectively); the subcutaneous collagen deposition beneath the airway epithelium increased significantly in S.pp group than that in control group (45.54±5.79 vs. 26.3±5.53, P=0.001). The number of goblet cells and inflammatory cell infiltration showed no statistical significance between the two groups. Conclusion Neonatal S.pp may lead to airway epithelial injury and be involved in the formation of AHR.

¿Es la patogenia del virus sincitial respiratorio humano un factor de riesgo para el desarrollo de asma infantil? / Is the pathogenesis of the human respiratory syncytial virus a risk factor for the development of childhood asthma?

Resumen El virus sincitial respiratorio humano (VSRh) es considerado como el principal agente causal de infecciones del tracto respiratorio en niños. Su presentación clínica varía en cuanto a la gravedad: desde infecciones no complicadas de la vía aérea superior en adultos y niños sanos, hasta bronquiolitis y bronconeumonía en niños con factores de riesgo y menores de 2 años. Perteneciente a la familia Pneumoviridae y al género Orthopneumovirus, el VSRh es un virus envuelto que contiene un genoma de ácido ribonucleico (RNA) monocatenario de polaridad negativa, que codifica para 7 proteínas estructurales (G, F, SH, M, P, N y L) y 4 no estructurales (NS1, NS2, M1, M2). La presencia del virus se ha considerado como factor de riesgo para el desarrollo de asma infantil, que es una enfermedad inflamatoria de la vía aérea caracterizada por episodios recurrentes de obstrucción de la vía aérea inferior ante estímulos ambientales generalmente inocuos. El riesgo de desarrollar asma aumenta si la primoinfección sucede a edad temprana y si hay factores de riesgo como prematuridad y broncodisplasia pulmonar. En México, debido a la morbilidad y mortalidad asociada al VSRh, y como profilaxis en pacientes de alto riesgo; desde el año 2008, se recomienda el uso del biofármaco Pavilizumab. El objetivo de la presente revisión es describir los factores asociados a la patogénesis VSRh que podrían estar implicados en el desarrollo del asma infantil y, con ello, plantear que población está en riesgo. Para estos fines, se presenta un breve análisis de la biología del virus, la respuesta inmune que se induce durante la infección, así como aquellos fármacos aprobados en México para el tratamiento y profilaxis de infecciones asociadas al VRSh.

Abstract The human respiratory syncytial virus (hRSV) is the main pathogen of respiratory tract infections in children. The severity of the infection is depending of its clinical presentation that is moving from uncomplicated upper airway infections, in healthy adults and children, to bronchiolitis and bronchopneumonia that could be developed, in presence of risk factors, in children younger than 2 years. The virus belongs to the Pneumoviridae family and Orthopneumovirus genus, it is an enveloped virus with a single-stranded RNA genome of negative polarity that is codifying 7 structural proteins (G, F, SH, M, P, N and L) and four non-structural proteins (NS1, NS2, M1, M2). The viral infection has been considered as a risk factor for the development of childhood asthma, which is the most common airway inflammatory disease in children and characterized, by recurrent episodes of lower airway obstruction, by harmless environmental stimuli. The risk increases if primary infection occurs at an early age and in risk factors as prematurity and pulmonary broncho-dysplasia. Due to the morbidity and mortality associated with hRSV, since 2008 it has been approved the use of biopharmaceuticals as Palivizumab for prophylaxis in high-risk patients. In the present review, the aim is to present those factors that could be involved in the development of childhood asthma and their possible link to the presence of hRSV. In addition, it is an intention for presenting the possible facts of the risks in the potentially infected population. For a better comprehension of the virus, it is presented a briefly analysis of the viral structure, the induced immune response against the viral infection and those drugs that are approved in Mexico for the treatment and prophylaxis against hRSV.

Prevalence, Risk Factors and Cutoff Values for Bronchial Hyperresponsiveness to Provocholine in 7-Year-Old Children

BACKGROUND: A US Food and Drug Administration (FDA)-approved drug methacholine chloride (Provocholine®) was recently introduced to Korea where it is now widely used in clinical practice. We aimed to evaluate the prevalence, risk factors and cutoff value of bronchial hyperresponsiveness (BHR) to Provocholine in 7-year-old children. METHODS: Six hundred and thirty-three children from the Panel Study on Korean Children who visited 16 regional hospitals were evaluated. Skin prick tests, spirometry and bronchial provocation tests for Provocholine as well as a detailed history and physical examinations were performed. The bronchial provocation test was reliably performed on 559 of these children. RESULTS: The prevalence of ever-diagnosed asthma via medical records was 7.7%, and that of current asthma (wheezy episode in the last 12 months + diagnosed asthma by physicians) was 3.2%. The prevalence of BHR to Provocholine was 17.2% and 25.8%, respectively, for a PC20 < 8 and < 16 mg/mL. The risk factors for BHR (PC20 < 16 mg/mL) were atopic dermatitis diagnosis and current dog ownership, whereas those for current asthma were allergy rhinitis diagnosis, a history of bronchiolitis before the age of 3, recent use of analgesics/antipyretics and maternal history of asthma. The BHR prevalence trend showed an increase along with the increased immunoglobulin E (IgE) quartile. The cutoff value of PC20 for the diagnosis of current asthma in children at age 7 was 5.8 mg/mL (sensitivity: 47.1%, specificity: 87.4%). CONCLUSIONS: BHR to Provocholine (PC20 < 8 mg/mL) was observed in 17.2% of 7-year-olds children from the general population and the cutoff value of PC20 for the diagnosis of current asthma was 5.8 mg/mL in this age group. The risk factors for BHR and current asthma showed discrepancies suggesting different underlying mechanisms. Bronchial provocation testing with Provocholine will be a useful clinical tool in the future.

Cat ownership is associated with increased asthma prevalence and dog ownership with decreased spirometry values

The association between pet ownership and the development of allergic and respiratory diseases has been the aim of several studies, however, the effects of exposure in adults remain uncertain. The aims of the present study were to investigate the prevalence of asthma and lung function status among dog and cat owners. This cross-sectional study was performed at two universities with students and workers who were allocated into 3 groups according to pet ownership in the previous year: cat owners, dog owners, and no pets (control group). Subjects underwent spirometry, bronchial challenge test with mannitol, skin prick tests, and questionnaires about animal exposures and respiratory symptoms. Control group comprised 125 subjects; cat owner group, 51 subjects; and dog owner group, 140 subjects. Cat owners had increased asthma prevalence (defined by symptoms and positive bronchial challenge test), but no changes in lung function compared to the control group. The dog owner group had lower spirometry values (forced expiratory volume in one second and lower forced vital capacity), but similar asthma prevalence, compared to the control group. In the cat owner group, excess of asthma may have an immunological basis, since we found an association with atopy. Although we did not have endotoxin data from volunteers' households, we postulated that low values of lung function were associated to exposure to endotoxins present in environments exposed to dogs.

THE DIAGNOSIS AND DIFFERENTIAL DIAGNOSIS OF ASTHMA IN ADOLESCENTS AND ADULTS

Asthma is the most common chronic respiratory illnessworldwide, and makes up a large part of primary carepractice. Family physicians need to be well-versed inasthma diagnosis, while avoiding overdiagnosis ormisdiagnosis. The tetrad of cough, chest tightness,wheezing and dyspnea are conventionally thought to bethe key presenting symptoms of asthma. However, thesesymptoms can occur in many other conditions, makingaccurate diagnosis of asthma challenging. This article aimsto outline the clinical features and investigations that can help the family physician diagnose asthma and formpossible differential diagnoses in adolescents and adults.Diligent history-taking remains paramount for diagnosis,while no investigation is definitive.

Accuracy of spirometry for detection of asthma: a cross-sectional study

ABSTRACT BACKGROUND: Asthma is a chronic inflammatory disease with airway hyperresponsiveness. Spirometry is the most commonly used test among asthmatic patients. Another functional test used for diagnosing asthma is the bronchial challenge test. The aim of this study was to analyze the accuracy of spirometry for detecting asthma in the general population. DESIGN AND SETTING: Cross-sectional study with data analysis to evaluate the accuracy of spirometry through calculating sensitivity, specificity and predictive values and through the kappa agreement test. METHODS: Subjects who constituted a birth cohort were enrolled at the age of 23 to 25 years. Spirometric abnormality was defined as reduced forced expiratory volume in one second, i.e. lower than 80% of the predicted value. Measurement of bronchial responsiveness was performed by means of the bronchial challenge test with methacholine. The gold-standard diagnosis of asthma was defined as the presence of bronchial hyperresponsiveness in association with respiratory symptoms. RESULTS: Asthma was detected in 200 subjects (10.4%) out of the sample of 1922 individuals. Spirometric abnormality was detected in 208 subjects (10.9%) of the sample. The specificity of spirometric abnormality for detecting asthma was 90%, sensitivity was 23%, positive predictive value was 22%, and negative predictive value was 91%. The kappa test revealed weak agreement of 0.13 (95% confidence interval, CI: 0.07-0.19) between spirometry and the diagnosis of asthma. CONCLUSION: Spirometry, as a single test, has limitations for detecting asthma in the general population.

Risk factors, lung function and bronchial hyperresponsiveness in current dust mite-induced allergic rhinitis

PURPOSE: We analyzed the pulmonary function and risk factors of allergic rhinitis (AR) in dust mite-sensitized children with current AR and no history of asthma. METHODS: In this cross-sectional study, demographic and disease-related information was obtained from 1,792 Korean children aged 9-12 years using a questionnaire, skin-prick testing, spirometric analysis, and methacholine challenge testing. RESULTS: A total of 672 children were analyzed. The control group consisted of 583 children without any allergic diseases who were not sensitized to 16 common allergens. The group with current AR and dust mite sensitization consisted of 89 children. Binary logistic regression analysis showed that helminth infection (adjusted odds ratio [aOR], 2.88; 95% confidence interval [CI], 1.23-6.77) and antibiotic use during infancy (aOR, 1.89; 95% CI, 1.10-3.25) were the risk factors. Pet ownership (aOR, 0.32; 95% CI, 0.15-0.69) and older siblings (aOR, 0.58; 95% CI, 0.35-0.96) were protective factors. Spirometry results did not differ between the control and dust mite-induced AR groups. None of the children showed a bronchodilator response. However, 8.5%, 7.1%, and 2.1% of the control-group children and 28.7%, 23.0%, and 8.0% of the dust mite-induced AR-group children showed methacholine PC20 (provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second) values of < or =25 mg/mL, < or =16 mg/mL, and < or =8 mg/mL, respectively (P<0.01). CONCLUSION: The prevalence of current dust mite-induced AR may be reduced by controlling environmental factors. Even though the spirometry results seemed to be normal, bronchial hyperresponsiveness occurred more frequently in children with dust mite-induced AR than in normal children.

The Lung Function Impairment in Non-Atopic Patients With Chronic Rhinosinusitis and Its Correlation Analysis

OBJECTIVES: Chronic rhinosinusitis (CRS) is common disease in otorhinolaryngology and will lead to lower airway abnormality. However, the only lung function in CRS patients and associated factors have not been much studied. METHODS: One hundred patients with CRS with nasal polyps (CRSwNP group), 40 patients with CRS without nasal polyps (CRSsNP group), and 100 patients without CRS were enrolled. The difference in lung function was compared. Meanwhile, CRSwNP and CRSsNP group were required to undergo a bronchial provocation or dilation test. Additionally, subjective and objective outcomes were measured by the visual analogue scale (VAS), 20-item Sino-Nasal Outcome Test (SNOT-20), Lund-Mackay score, Lund-Kennedy endoscopic score. The correlation and regression methods were used to analyze the relationship between their lung function and the above parameters. RESULTS: The forced expiratory volume in 1 second (FEV1) and forced expiratory flow between 25% and 75% of forced vital capacity (FEF25-75) of CRSwNP group were significantly lower than other groups (P<0.05). On peak expiratory flow, there was no difference between three groups. In CRSwNP group, FEV1 was negatively correlated with peripheral blood eosinophil count (PBEC) and duration of disease (r=–0.348, P=0.013 and r=–0.344, P=0.014, respectively), FEF25-75 negatively with VAS, SNOT-20 (r=–0.490, P=0.028 and r=–0.478, P=0.033, respectively) in CRSsNP group. The incidence of positive bronchial provocation and dilation test was lower in CRSwNP group (10% and 0%, respectively), with both 0% in CRSsNP group. The multiple linear regression analysis indicated that change ratio of FEV1 before and after bronchial provocation or dilation test were correlated with PBEC in CRSwNP group (β=0.403, P=0.006). CONCLUSION: CRS leading to impaired maximum ventilation and small airway is associated with the existence of nasal polyp. Lung function impairments can be reflected by PBEC, duration, VAS, and SNOT-20. In CRSwNP patients, PBEC is independent predictor of FEV₁ change ratio.

Inhalation therapy in mechanical ventilation / Terapia inalatória em ventilação mecânica

Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients.

Pacientes com doenças pulmonares obstrutivas frequentemente necessitam de suporte ventilatório através de ventilação mecânica invasiva ou não invasiva, dependendo da gravidade da exacerbação. O uso de broncodilatadores inalatórios pode reduzir significativamente a resistência das vias aéreas, contribuindo para a melhora da mecânica respiratória e da sincronia do paciente com o respirador. Apesar dos diversos estudos publicados, pouco se conhece sobre a eficácia dos broncodilatadores rotineiramente prescritos para pacientes em ventilação mecânica ou sobre sua distribuição pulmonar. Os agonistas beta-adrenérgicos e as drogas anticolinérgicas são os broncodilatadores inalatórios mais usados em UTIs. Muitos fatores podem influenciar no efeito das drogas broncodilatadoras, entre eles o modo ventilatório, a posição do espaçador no circuito, o tamanho do tubo, a formulação/dose da droga, a gravidade da doença e a sincronia do paciente. O conhecimento das propriedades farmacológicas das drogas broncodilatadoras e das técnicas adequadas para sua administração são fundamentais para otimizar o tratamento desses pacientes.

Association of nasal inflammation and lower airway responsiveness in schoolchildren based on an epidemiological survey

BACKGROUND/AIMS: We sought to increase our understanding of the rhinitis-asthma relationship and improve strategies for the treatment of patients with these diseases. The aim of this study was to identify a connection between upper airway inflammation and lower airway responsiveness. METHODS: We counted eosinophils on nasal smears, and performed spirometry, allergic skin tests, and methacholine challenge tests in 308 schoolchildren plus a questionnaire on respiratory symptoms. The methacholine concentration causing a 20% fall in forced expiratory volume in 1 second (PC20 0.05). No difference in BHR was detected when comparing subjects with and without nasal eosinophils. There were significant differences in the PC20 between subjects with greater than 50% nasal eosinophils and without nasal eosinophils (11.01 +/- 2.92 mg/mL vs. 17.38 +/- 0.61 mg/mL; p < 0.001). CONCLUSIONS: These findings demonstrated that nasal eosinophilic inflammation might contribute to lower airway responsiveness in schoolchildren, based on an epidemiological survey.

Effect of Traffic-Related Air Pollution on Allergic Disease: Results of the Children's Health and Environmental Research

PURPOSE: This study evaluated the relationship of living near to main roads to allergic diseases, airway hyperresponsiveness (AHR), allergic sensitization, and lung function in Korean children. METHODS: A total of 5,443 children aged 6-14 years from 33 elementary schools in 10 cities during 2005-2006 were included in a baseline survey of the Children's Health and Environmental Research. We assessed association of traffic-related air pollution (TAP) exposure with the distance to the nearest main road, total road length of main roads and the proportion of the main road area within the 200-m home area. RESULTS: Positive exposure-response relationships were found between the length of the main road within the 200-m home area and lifetime wheeze (adjusted prevalence ratio [PR] for comparison of the longest to the shortest length categories=1.24; 95% CIs, 1.04-1.47; P for trend=0.022) and diagnosed asthma (PR=1.42; 95% CIs, 1.08-1.86; P for trend=0.011). Living less than 75 m from the main road was significantly associated with lifetime allergic rhinitis (AR), past-year AR symptoms, diagnosed AR, and treated AR. The distance to the main road (P for trend=0.001), the length of the main road (P for trend=0.041), and the proportion of the main road area (P for trend=0.006) had an exposure-response relationship with allergic sensitization. A strong inverse association was observed between residential proximity to the main load and lung function, especially FEV1, FEV1/FVC, and FEF25-75. The length of the main road and the proportion of the main road area were associated with reduced FEV1 in schoolchildren. CONCLUSIONS: The results of this study suggest that exposure to traffic-related air pollution may be associated with increased risk of asthma, AR, and allergic sensitization, and with reduced lung function in schoolchildren.

Exhaled nitric oxide and bronchial hyperresponsiveness in atopic asthmatic children with and without allergic rhinitis

PURPOSE: Children with asthma frequently have allergic rhinitis (AR) as a comorbidity. Asthmatic children with AR have a higher exhaled nitric oxide (eNO) level and bronchial hyperresponsiveness (BHR) than those without. The purpose of this study is to investigate the difference in lung function, eNO, and BHR between atopic asthma with and without AR, and the association of eNO and BHR with atopic intensity in total asthmatics. METHODS: We recruited 69 atopic asthmatic children with AR, 19 atopic asthmatic children without AR, 38 children with AR, and 43 nonatopic controls. We measured forced expiratory volume in one second (FEV1) and forced expiratory flow at 25% to 75% of forced vital capacity (FEF(25%-75%)), dose response slope (DRS) of bronchial challenge with methacholine and adenosine 5'-monophosphate (AMP), the levels of eNO, and the ratio of sum of allergen wheal diameter to histamine using skin prick tests. RESULTS: Atopic asthmatic children with AR had a higher eNO level compared to those without AR (P<0.05). However, there was no difference in FEV1 %predicted, FEF(25%-75%) %predicted, methacholine DRS, and AMP DRS between asthmatic children with and without AR. In total asthmatics, methacholine DRS and AMP DRS significantly correlated with eNO levels (r=0.338, P<0.001; r=0.365, P<0.001), but not with total IgE levels. However, eNO significantly correlated with total IgE levels (r=0.479, P<0.001). CONCLUSION: These results suggest that AR may enhance airway inflammation but may not lead to enhanced BHR in children with asthma.

Efeito do treinamento físico aeróbio na hiperresponsividade brônquica e no processo inflamatório pulmonar de pacientes com asma moderada a grave / Effect of aerobic training on bronchial hyperresponsiveness and pulmonary inflammation in patients with moderate to severe asthma

Introdução: A asma é caracterizada por um processo inflamatório crônico que está associado ao desenvolvimento da hiperresponsividade brônquica (HRB). O exercício físico regular proporciona inúmeros benefícios aos pacientes com asma porém, os efeitos do treinamento físico na HRB permanecem pouco compreendidos. Objetivo: Avaliar o efeito do treinamento físico aeróbio na hiperresponsividade brônquica, inflamação pulmonar, controle clínico e fatores relacionados à qualidade de vida de pacientes adultos com asma persistente moderada a grave. Métodos: Cinquenta e oito adultos com asma moderada a grave foram divididos aleatoriamente, em dois grupos: Controle (GC, n=28) e Treinado (GT, n=30). Os pacientes do GC foram submetidos a um programa educacional e a um programa de exercícios respiratórios, enquanto os pacientes do GT foram submetidos a todos os procedimentos do GC e a um programa de condicionamento físico aeróbio. A hiperresponsividade brônquica foi avaliada através do teste de broncoprovocação inespecífica com histamina antes e após a intervenção. Nestas ocasiões, todos os pacientes também realizaram, análise do escarro induzido e da fração exalada de óxido nítrico, espirometria, teste ergoespirométrico e responderam aos questionários de controle clínico, fatores de saúde relacionados à qualidade de vida (FSRQV) e níveis de depressão. Além disso, foi coletada uma amostra do sangue venoso dos pacientes para quantificação do IgE total e de IgE específica. Resultados: Após três meses de intervenção, os pacientes do GT aumentaram 1 dupla dose de concentração (dd) (1 dd; 0,3-1,7 dd, 95% CI) (p < 0,05) enquanto o GC (0,06 dd; -0,6dd a 0,7 dd, 95% CI) não apresentou mudança significativa na hiperresponsividade brônquica. A inflamação pulmonar reduziu apenas nos pacientes do GT que apresentaram níveis elevados de eosinófilos (> 3%) e FeNO (> 26ppb) (p < 0,05). O condicionamento aeróbio melhorou os FSRQV, controle clínico da asma e níveis...

Introduction: Asthma is characterized by a chronic inflammatory process that is associated with the development of bronchial hyperresponsiveness (BHR). Regular exercise provides numerous benefits in patients with asthma; however, the effects of exercise training on BHR remain poorly understood. Objective: To evaluate the effect an aerobic training on bronchial hyperresponsiveness, pulmonary inflammation, clinical control and health related quality of life (HRQoL) in adults patients with moderate to severe asthma. Methods: Fifty-eigth patients adults with moderate to severe asthma were randomly assigned into two groups: Control (CG, n = 28) and Trained (TG, n = 30).The GC patients undertake an educational program and performed breathing exercises, while the TG patients underwent the same procedures than CG plus an aerobic training program. Bronchial hyperresponsiveness was assessed by nonspecific bronchial provocation test with histamine before and after the intervention. On these occasions, all patients also performed induced sputum analysis and fractional exhaled nitric oxide (FeNO), spirometry, cardiopulmonary exercise testing and fulfilled questionnaires to evaluate clinical control test, HRQoL and depression levels. In addition, blood samples were collect in order to quantify total serum immunoglobulin (IgE) and specific IgE. Results: After 3 months of intervention, the TG increased 1 double dose of concentration (dd) (0.3 to 1.7 dd, 95% IC) and CG did not change significantly on bronchial hyperresponsiveness 0.06 dd (-0.6 to 0.7 dd, 95% IC) (p < 0.05).The pulmonary inflammation reduced only in the GT patients with high levels of eosinophils (> 3%) and FeNO (> 26ppb) (p < 0.05). Aerobic training also improved HRQoL, clinical control and depression levels (p < 0.05).Conclusion: Our results demonstrate that aerobic training...