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Background Near-fatal asthma (NFA) is a heterogeneous clinical entity and several profiles of patients have been described according to different clinical, pathophysiological and histological features. However, there are no previous studies that identify in a unbiased way – using statistical methods such as clusters analysis – different phenotypes of NFA. Therefore, the aim of the present study was to identify and to characterize phenotypes of near fatal asthma using a cluster analysis. Methods Over a period of 2 years, 33 Spanish hospitals enrolled 179 asthmatics admitted for an episode of NFA. A cluster analysis using two-steps algorithm was performed from data of 84 of these cases. Results The analysis defined three clusters of patients with NFA: cluster 1, the largest, including older patients with clinical and therapeutic criteria of severe asthma; cluster 2, with an high proportion of respiratory arrest (68%), impaired conciousness level (82%) and mechanical ventilation (93%); and cluster 3, which included younger patients, characterized by an insufficient anti-inflammatory treatment and frequent sensitization to Alternaria alternata and soybean. Conclusions These results identify specific asthma phenotypes involved in NFA, confirming in part previous findings observed in studies with a clinical approach. The identification of patients with a specific NFA phenotype could suggest interventions to prevent future severe asthma exacerbations.

During the past 10 years, the acoustic analysis of breath sounds has been used as a diagnostic tool in patients suffering from obstructive respiratory diseases. Acoustic analysis might be able to monitor the response to bronchodilator therapy in a clinical setting. So far, few studies have been carried out in asthmatic patients. To assess the responses of a sampling of asthma patients to an inhaled bronchodilator (terbutaline) by means of spectral analysis of the tracheal sound performed during forced expiratory maneuvers.Seventeen nonsmoking asthma patients (9 were male, 8 were female) who had been suffering from the disease foror = 15 years were included in the study, as were 15 normal subjects (7 were male, 8 were female). The average age (+/- SD) was 56.5 +/- 15.2 years (FVC, 2.7 +/- 0.9 L [63.4%]; FEV1, 1.5 +/- 0.6 L [53.0%]). The tracheal sounds were collected during three forced expiratory maneuvers with a sampling frequency of 5,000 Hz and were analyzed by applying a 16-parameter autoregressive model.The centroid frequency decreased after the bronchodilator was given at different flow segments between 1.2 and 0.4 L/s, with significant changes between 0.6 and 0.4 L/s.Patients with asthma showed changes in the spectral acoustic analysis frequencies after the administration of a bronchodilator drug (terbutaline) during forced expiratory maneuvers.

To analyze which factors were related to the development of pleural thickening in pleural tuberculosis (PT).We reported 99 patients diagnosed as having PT separated into two different groups according to the presence of radiographic pleural thickening after completing the treatment: normal chest roentgenogram (group 1) or pleural thickening (group 2). We compared: clinical history, chest radiography, pleural fluid analysis, microbiological studies and effects of the treatment.35 cases in group 1 (35.35%) and 64 in group 2 (64.45%). All the compared results did not differ between the two groups, excluding a higher incidence of febrile cases, increased white cell count and decreased relative percentage of pleural lymphocytes in group 1, and increased number of cases with hemoptysis, positive sputum cultures in patients with parenchymal infiltrates, relative percentage of pleural lymphocytes and decreased white cell count in group 2.We reported an elevated incidence of residual pleural thickening, but it is unlikely that all the cases could have any clinical significance. We didn't confirm a characteristic pattern. Our findings suggested that a different reaction related or not to the hypersensitivity, rather than the inflammatory response to infection was the responsible for the fibrosis.

BACKGROUND: Minor differences in technique may account for the wide range of published normal values of maximum expiratory and inspiratory pressures. The effects of holding the lips while the subject performed a maximal expiratory pressure manoeuvre were investigated in this study. METHODS: Maximum static expiratory pressures (PEmax) obtained with a cylindrical tube by means of lip compression by the subject and technician aided compression were compared in 20 men (mean age 27 years) and 20 women (mean age 28 years). RESULTS: Technician aided lip compression was associated with higher maximum expiratory pressure than compression by the subject in both men (195 v 110 cm H2O) and women (134 v 80 cm H2O). CONCLUSION: Compression of the lips and corners of the mouth should be performed by a trained technician for maximum expiratory pressure measurements when a cylindrical mouthpiece is used.

Se midieron las presiones inspiratorias maximas estaticas (pico y meseta) —PIM— en diez sujetos normales. Las medidas fueron repetidas 6 veces a lo largo de 6 semanas consecutivas. Se observo un aumento estadisticamente significativo a partir de la cuarta determinacion en la presion pico y de la sexta en la presion meseta. La presion pico y la presion meseta se comportaron siempre de un modo similar siendo su diferencia practicamente constante a lo largo de las seis semanas. En consecuencia, creemos que para una interpretacion correcta de la PIM debe de tenerse en cuenta el efecto aprendizaje. Con fines practicos la presion pico puede ser usada para medir la funcion muscular al igual que la presion meseta.

To determine the number of maximal mouth pressure manoeuvres needed to obtain a reproducible value of maximal inspiratory mouth pressure (MIP), we studied 44 patients with chronic airflow obstruction, with a mean (SD) % predicted FEV1 value of 53.9 (25), who were clinically stable. Maximal inspiratory mouth pressure was determined with an anaeroid manometer during maximal inspiratory efforts in a quasi static condition at residual volume. All patients performed 20 consecutive maximal inspiratory mouth manoeuvres, each one separated by 30-40 seconds. The mean (SD) values of MIP varied from 71.5 (25.5) cm H2O at the first measurement to 80.1 (27) cm H2O at the last measurement. Maximal values of MIP were usually achieved after nine determinations. It is concluded that to obtain a reproducible MIP value in patients with chronic airflow obstruction who are untrained and unexperienced in such manoeuvres a minimum of nine technically acceptable maximal mouth pressure manoeuvres should be performed.