Abstract Objective: To evaluate whether respiratory therapy techniques influence the number of cells within and quantity of induced sputum in patients with asthma or chronic obstructive pulmonary disease (COPD). Methods: Randomized clinical trial, in which patients with asthma or COPD under intervention (n = 16 and 10, respectively) were compared with control groups (n = 16 and 10). Patients in the asthma/intervention (A/I) and COPD/intervention (C/I) groups were submitted to oscillating positive expiratory pressure maneuvers for 5 min, followed by 10 forced expiratory technique sequences. These patients were also submitted to an induced sputum protocol with inhaled hypertonic saline (3%, 4% or 5%; A/I group) or inhaled isotonic saline (C/I group). The asthma/control (A/C) and COPD/control (C/C) groups were submitted only to the standard induced sputum protocol. Results: The final mean weight of the sputum samples was significantly greater in the A/I group than in the A/C group (2,767.25 ± 998.08 mg vs. 1,689.17 ± 1,189.96 mg; p = 0.03). The mean/median total cell counts (×106/mL) were higher in the A/I and C/I groups than in the A/C and C/C groups (4.06/0.95 and 0.63/0.39, p = 0.05, vs. 5.08/1.77 and 0.64/0.40, p = 0.02). There were no statistically significant differences among the groups in terms of cell viability. Conclusions: The use of respiratory therapy techniques can increase sputum sample weight in asthma patients, as well as increasing total cell counts in patients with asthma or COPD.

Keywords: Asthma; Pulmonary disease, obstructive chronic; Sputum; Physical therapy modalities.

Objective: To determine the effectiveness of oscillating positive expiratory pressure (OPEP) using predetermined expiratory pressures on the viscosity and transportability of sputum in patients with bronchiectasis. Methods: The study involved 15 stable patients with bronchiectasis (7 males; mean age = 53 ± 16 years), submitted to two consecutive OPEP interventions, with a 24-h interval between the two, using positive expiratory pressures set at 15 cmH2O (P15) and 25 cmH2O (P25). The protocol consisted of a voluntary cough; another voluntary cough 20 min later, designated time zero (T0); a 10-min rest period; and two 10-min series (S1 and S2, using OPEP at P15 and P25 in both), with a 10-min interval between the two. The viscosity and transportability of sputum were evaluated by viscometry, relative transport velocity on frog palate, transport in a simulated cough machine and contact angle. Sputum samples were collected at T0, after S1 and after S2. Specific statistical tests were performed depending on the type of data distribution. Results: In comparison with the values obtained at T0, sputum viscosity decreased significantly after S1 at P15 and after S2 at P25. There were no significant differences among all of the samples in terms of transportability. Conclusions: The fact that sputum viscosity decreased whether OPEP was performed at P15 or at P25 suggests that there is no need to generate high expiratory pressure to achieve the desired result.

Keywords: Viscosity; Bronchiectasis; Physical therapy (specialty); Sputum.

Objective: To determine cell profiles, as well as to identify CD4+ and CD8+ lymphocyte subgroups, in induced sputum (IS) and peripheral venous blood (PVB) of patients with chronic obstructive pulmonary disease (COPD). Methods: Total cell counts and counts of individual cell types, including CD4+ and CD8+ T lymphocytes, were determined in the IS and PVB of 85 subjects (38 with COPD without exacerbation, 29 smokers without obstruction and 18 nonsmokers). Mann-Whitney and Spearman non-parametric tests were used in the statistical analysis, and values of p < 0.05 were considered statistically significant. Results: Comparing the IS of subjects with COPD to that of nonsmokers, neutrophil, eosinophil and CD8+ T lymphocyte counts were higher (respectively p = 0.005, p < 0.05 and p < 0.05), whereas the percentage of macrophages was lower (p = 0.003). There were weak linear correlations (r2 < 0.1) between each cell type in IS and forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and FEV1/FVC ratio. Eosinophil and CD8+ T lymphocyte counts were also higher in PVB (p = 0.04 and p = 0.02). Conclusions: In patients with stable COPD, CD8+ T lymphocyte counts were higher in PVB, whereas total leukocyte counts were similar to those of the other two groups analyzed, suggesting systemic inflammatory involvement. The CD8+ T lymphocyte count in blood can be a useful marker of systemic inflammation and can help identify smokers who already present a COPD inflammatory pattern.

Keywords: Sputum; T-lymphocytes; Neutrophils; Macrophages; Eosinophils; Pulmonary disease, chronic obstructive.

Objective: To investigate the effects of manual chest compression (MCC) on the expiratory flow bias during the positive end-expiratory pressure-zero end-expiratory pressure (PEEP-ZEEP) airway clearance maneuver applied in patients on mechanical ventilation. The flow bias, which influences pulmonary secretion removal, is evaluated by the ratio and difference between the peak expiratory flow (PEF) and the peak inspiratory flow (PIF). Methods: This was a crossover randomized study involving 10 patients. The PEEP-ZEEP maneuver was applied at four time points, one without MCC and the other three with MCC, which were performed by three different respiratory therapists. Respiratory mechanics data were obtained with a specific monitor. Results: The PEEP-ZEEP maneuver without MCC was enough to exceed the threshold that is considered necessary to move secretion toward the glottis (PEF − PIF difference > 33 L/min): a mean PEF − PIF difference of 49.1 ± 9.4 L/min was achieved. The mean PEF/PIF ratio achieved was 3.3 ± 0.7. Using MCC with PEEP-ZEEP increased the mean PEF − PIF difference by 6.7 ± 3.4 L/min. We found a moderate correlation between respiratory therapist hand grip strength and the flow bias generated with MCC. No adverse hemodynamic or respiratory effects were found. Conclusions: The PEEP-ZEEP maneuver, without MCC, resulted in an expiratory flow bias superior to that necessary to facilitate pulmonary secretion removal. Combining MCC with the PEEP-ZEEP maneuver increased the expiratory flow bias, which increases the potential of the maneuver to remove secretions.

Keywords: Physical therapy modalities; Critical care; Respiration, artificial; Bodily secretions.

Objective: To evaluate the effects of positive expiratory pressure (PEP) on pulmonary epithelial membrane permeability in healthy subjects. Methods: We evaluated a cohort of 30 healthy subjects (15 males and 15 females) with a mean age of 28.3 ± 5.4 years, a mean FEV1/FVC ratio of 0.89 ± 0.14, and a mean FEV1 of 98.5 ± 13.1% of predicted. Subjects underwent technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA) radioaerosol inhalation lung scintigraphy in two stages: during spontaneous breathing; and while breathing through a PEP mask at one of three PEP levels-10 cmH2O (n = 10), 15 cmH2O (n = 10), and 20 cmH2O (n = 10). The 99mTc-DTPA was nebulized for 3 min, and its clearance was recorded by scintigraphy over a 30-min period during spontaneous breathing and over a 30-min period during breathing through a PEP mask. Results: The pulmonary clearance of 99mTc-DTPA was significantly shorter when PEP was applied-at 10 cmH2O (p = 0.044), 15 cmH2O (p = 0.044), and 20 cmH2O (p = 0.004)-in comparison with that observed during spontaneous breathing. Conclusions: Our findings indicate that PEP, at the levels tested, is able to induce an increase in pulmonary epithelial membrane permeability and lung volume in healthy subjects.

Keywords: Lung/metabolism; Technetium Tc 99m pentetate/pharmacokinetics; Radiopharmaceuticals; Positive-pressure respiration.

Objective: To evaluate the electromyographic activity (EA) of sternocleidomastoid (SCM) and scalene muscles during and after the use of expiratory positive airway pressure (EPAP) in patients with COPD. Methods: This was a clinical single-blind trial involving 13 healthy subjects as controls and 12 patients with stable COPD. At baseline, we determined EA during spontaneous respiration, lung function parameters, and respiratory muscle strength. Subsequently, EPAP at 15 cmH2O was applied by means of a face mask for 25 min, during which the EA of the SCM and scalene muscles was recorded every 5 min. A final record was obtained 10 min after the mask removal. Results: We found that the behavior of the EA of SCM and scalene muscles was comparable between the controls and the COPD patients (p = 0.716 and p = 0.789, respectively). However, during the use of EPAP, both muscles showed a trend toward an increase in the EA. In addition, there was a significant decrease in the EA of the SCM between the baseline and final measurements (p = 0.034). Conclusions: The use of EPAP promoted a significant reduction in the EA of the SCM in the controls and in the patients with stable COPD. However, this did not occur regarding the EA of the scalene muscle.

Keywords: Electromyography; Respiratory muscles; Pulmonary disease, chronic obstructive; Positive-pressure respiration.

Objective: To evaluate the usefulness of determining the inflammatory component of airway diseases (inflammometry) by induced sputum cell counts, as well as its influence on treatment decisions in a tertiary facility for the treatment of respiratory diseases. Methods: We analyzed 151 sputum samples from 132 consecutive patients referred for clinical sputum induction by five pulmonologists between July of 2006 and February of 2007. A structured questionnaire related to the reasons for requesting the test and to the therapeutic decision making based on test results was completed by each attending physician upon receiving the test results. Induced sputum was obtained and processed according to a technique previously described. Results: The principal motives for ordering the test were inhaled corticosteroid dose titration in patients with moderate-to-severe asthma (in 54.3%), investigation of chronic cough (in 30.5%), and monitoring airway inflammation in patients with bronchiectasis (in 7.3%) or chronic obstructive pulmonary disease (in 6%). Of the 82 patients with asthma, 47 (57%) presented eosinophilic bronchitis (>3% eosinophils). Nonasthmatic eosinophilic bronchitis was diagnosed in 9 (19%) of the 46 patients with chronic cough. Neutrophilic bronchitis (>65% neutrophils) was found in 13 patients, of which 5 had asthma, 2 had chronic cough, and 6 had chronic obstructive pulmonary disease/bronchiectasis. Based on the induced sputum results, the corticosteroid dose was modified in 48 asthma patients (64.7%). Conclusions: The systematic application of inflammometry using induced sputum cell counts can be beneficial for patients with airway diseases, particularly those with asthma or chronic cough.

Keywords: Sputum; Asthma; Bronchitis.

Objective: To assess the frequency of variation in forced expiratory volume in one second after bronchodilator use in a sample of patients with chronic obstructive pulmonary disease, correlating such variation with clinical and demographic variables and evaluating the frequency of response presented in forced vital capacity, slow vital capacity, inspiratory capacity, residual volume, airway resistance and specific airway conductance. Methods: A total of 64 patients with chronic obstructive pulmonary disease were submitted to whole body plethysmography, and reversibility of bronchoconstriction after the administration 400 µg of fenoterol was quantified. Results: A response in forced expiratory volume in one second was observed in 31% of the patients. Excluding patients presenting a response in forced expiratory volume in one second, 5% presented responses in 5 of the other 6 parameters, 10% presented responses in 4 parameters, 17.5% in 3 parameters, 27.5% in 2 parameters, and 25% in only 1 parameter. Conclusion: When included in the evaluation of bronchodilator response together with forced expiratory volume in one second, static lung volumes, airway resistance and airway conductance allowed a broader evaluation of those patients presenting a functional pharmacodynamic response. These results are in accordance with the observation that bronchodilator use provides clinical improvement and relief of dyspnea to many patients with chronic obstructive pulmonary disease, even to those in whom such treatment leads to no improvement in forced expiratory volume in one second.

Keywords: Pulmonary disease, chronic obstructive/drug therapy; Bronchodilator agents/therapeutic use; Airway resistance/drug effects; Respiratory function tests; Vital capacity; Forced expiratory volume

Background: Pulmonary Rehabilitation (PR) improves the quality of life of chronic obstructive pulmonary disease (COPD) patients. However, the influence of PR on the sleep pattern of these patients is unknown. Objective: To evaluate the influence of PR on the sleep patterns of patients with COPD. Method: A total of 27 patients (22 men/5 women) were submitted to polysomnographic, gasometric and anthropometric studies before and after six weeks of PR and were evaluated using the Epworth Sleepiness Scale. The results were analyzed using paired Student's t-test, ANOVA and Newman-Keuls multiple comparison test. Results: Mean age was 63.3 5.3 years, mean FEV1 was 54.8 25.4% of predicted, mean FEV1/FVC was 49.9 12.0% of predicted, mean resting PaO2 was 69.7 7.3 mmHg, and mean resting SaO2 was 93.7 2.1%. Polysomnography revealed sleep patterns to be fragmented, with frequent waking and reduced slow-wave sleep, as well as oxygen desaturation. The most significant drops in oxygen saturation occurred during rapid eye movement sleep. No significant differences were observed between pre- and post-PR values for the other variables studied (p > 0.05).Conclusion: In the group of patients studied, PR did not alter sleep patterns.

Keywords: Sleep. Pulmonary Disease. Chronic Obstructive. Lung Diseases, rehabilitation.

Objective: Making the differential diagnosis between asthma and chronic obstructive pulmonary disease (COPD) based on the response to inhaled bronchodilators by means of spirometry is controversial.The objective of this study was to identify the most useful spirometric variables in order to distinguish between asthma and COPD. Methods: Retrospective study conducted from April of 2004 to January of 2006, comparing the spirometric parameters of 103 nonsmoking patients with asthma to those of 108 patients with COPD who were smokers for more than 10 pack-years. All of the patients included in the study were older than 40 and presented stable disease at the time of the test. Results: Initial forced expiratory volume in one second (FEV1) was the same in the two groups (pre-bronchodilator FEV1 = 51%). However, patients with COPD were older (66 ± 9 years vs. 59 ± 11 years, p < 0.001) and more frequently male (73% vs. 27%, p < 0,001).After the use of the bronchodilator, the median absolute difference in FEV1 was 0.25 L (range, −0.09 to 1.13 L) in patients with asthma and 0.09 L (range, −0.1 to 0.73 L) in those with COPD (p < 0.001).The highest sensitivity (55%), specificity (91%) and likelihood ratio (6.1) for asthma diagnosis was obtained when the percentage increase in postbronchodilator FEV1 in relation to the predicted FEV1 (Δ%predFEV1) was equal to or greater than 10%.Isolated significant increases in forced vital capacity were more common in patients with COPD. Conclusions: In patients over the age of 40 and presenting obstructive lung disease, a Δ%predFEV1 ≥ 10% is the best spirometric parameter to distinguish asthma from COPD.

Keywords: Spirometry; Respiratory function tests; Lung diseases, obstructive.

Background: Induced sputum is widely used in assessing airway inflammation. However, its utility as a diagnostic tool in the diagnosis of lung disease in immunosuppressed patients merits further investigation. Objectives: To determinate the diagnostic yield of sputum induction in the diagnosis of lung diseases in HIV-positive patients. Method: Subjects were selected from among HIV-positive patients older than 14 years who were evaluated at a reference hospital between January 2001 and September 2002. Those with respiratory symptoms for 7 days or longer with normal or abnormal chest X-rays, as well as those without respiratory symptoms but with abnormal chest X-rays, were included. All subjects were submitted to clinical examination, radiologic evaluation, sputum induction and laboratory testing. Subsequently, flexible fiberoptic bronchoscopy, bronchoalveolar lavage and transbronchial lung biopsy were performed. Samples were processed for Gram and Ziehl-Neelsen staining, quantitative culture for pyogenic bacteria, direct staining for fungi, culture for mycobacteria and fungi, silver stain for Pneumocystis jiroveci, as well as for total and differential cellularity determination. Results: A total of 54 patients were included. Upon testing negative for any etiologic agent, 7 patients were excluded, resulting in a total of 54 patients studied. A total of 60 infectious agents were isolated. Among the etiologic agents isolated, 46.7% were P. jiroveci, 33.5 were pyogenic bacteria and 16.7% were Mycobacterium tuberculosis. Sputum induction presented 57.5% sensitivity, 42.9% specificity, 87.1% predictive positive value, 13% predictive negative value and 55.6% overall accuracy. Conclusions: In this population, sputum induction proved to be a technique that is safe and easily performed, with a good diagnostic yield.

Keywords: HIV, Acquired Immunodeficiency Syndrome, Bronchoscopy, Sputum, Lung Disease/diagnosi.

Background: There is currently no consensus regarding which factors influence the quality of life of patients suffering from chronic obstructive pulmonary disease (COPD). However, identifying such factors could orient approaches to improving the quality of the lives of these patients. Objective: To evaluate factors that can interfere with quality of life in COPD patients selected for pulmonary rehabilitation. Methods: Twenty-one patients with moderate to severe COPD were evaluated. Maximal inspiratory pressure (MIP), 6-minute walk test (6MWT), body mass index (BMI), pulmonary function, blood gases, grip strength (measured with a dynamometer), quadriceps strength and St. George's Respiratory Questionnaire (SGRQ) scores were assessed. Results: Statistically significant negative correlations with quality of life were found for the following factors: "impact" scores of: forced expiratory volume in one second (FEV1) (r = -0.68; p = 0.004), FEV1 to forced vital capacity ratio (FEV1/FVC) (r = -0.61; p = 0.014), peak expiratory flow (PEF) (r = -0.53 (p = 0.015), 6MWT (r = -0.63; p = 0.001) and BMI (r = -0.64; p = 0.002); "activity" scores for: MIP (r = -0.57; p = 0.007), baseline arterial oxygen saturation by pulse oximetry (SpO2) (r = -0.52; p = 0.018) and 6MWT (r = -0.58; p = 0.007); "symptom" score for: BMI (r = -0.60; p = 0.005); and "total" scores for: FEV1 (r = -0.64; p = 0.01), PEF (r = -0.47; p = 0.033) and BMI (r = -0.57; p = 0.009). Multiple linear regression revealed the primary factors influencing quality of life to be: BMI, which presented a significant influence on "symptom", "impact" and "total" scores (p = 0.002, p = 0.009 and p = 0.024, respectively); and 6MWT, which had a significant influence on "activity" and "impact" scores (p = 0.048 and p = 0.010, respectively). Conclusions: The BMI and 6MWT were shown to have an influence on quality of life in the COPD patients studied. Therefore, therapeutic approaches to improving the quality of life of COPD patients should take these indices into consideration.

Keywords: Lung diseases, obstructive/rehabilitation. Quality of life

Background: Patients with chronic obstructive pulmonary disease usually present intolerance to physical exertion due to ventilatory limitation. L-carnitine has been used to enhance aerobic capacity in patients with chronic diseases, but no study seems to be available for this patient population. Objective: To evaluate the influence of L-carnitine supplementation (2 g/day) in chronic obstructive pulmonary disease patients undergoing physical training three times a week for six weeks. Method: Patients (mean age 69 ± 7 years, n = 30) with stable chronic obstructive pulmonary disease and < 65% of predicted forced expiratory volume in 1 second (FEV1) were separated into three groups of 10 patients each. Group 1 (G1, n = 10) received physical training and L-carnitine (2 g/day), group 2 (G2, n = 10) received physical training and placebo, and group 3 (G3, n = 10) received only L-carnitine (2 g/day). Spirometry and a 6-minute walking distance test were performed before and after intervention. Plasma levels of free carnitine were measured at the beginning and end of the study. Results: A significant increase in walking distance was found only in G1 and G2 (421 ± 100 to 508 ± 80.7 and 496 ± 78.7 to 526 ± 64.3 respectively). In addition, heart rates during physical training sessions were found to be significantly lower in G1 when compared to G2. There were no significant changes in spirometric variables, oxygen saturation or dyspnea in any group. Plasma levels of free L-carnitine were found to increase only in G3 (59.2 ± 13.8 to 102.3 ± 15.3 mmol/L). Conclusion: Oral L-carnitine supplementation combined with physical training may improve tolerance to physical exertion in chronic obstructive pulmonary disease patients.

Keywords: Chronic obstructive pulmonary disease. Carnitine/therapeutic use. Spirometry/methods. Exercise. Walking.

Background: Nasal and pharyngeal symptoms are common in patients with obstructive sleep apnoea (OSA) treated with nasal continuous positive airway pressure (CPAP). However, these symptoms are common in OSA patients even before the treatment. Objectives: Determine the impact of nasal CPAP on nasal and pharyngeal symptoms in OSA patients. Method: Thirty-five adult patients (28 males), age 54±10 years old, with OSA diagnosed by polissonography. All patients answered to a questionnaire about the presence and quantification of sneezing, rhinorrhea, nasal pruritus, obstruction and bleeding, nasal and pharyngeal dryness. The questionnaire was answered before and after at least three months of CPAP therapy. Results: The apnea-hypopnea index was 50±25 events per hour. Twenty six patients (74%) presented at least one naso-pharingeal symptom before treatment. Nasal obstruction was the most common symptom, being referred by 18 patients (51%). Among the patients that were initially assymptomatic (n=9), 78% developed adverse nasal reactions to CPAP. In contrast, among the patients that presented nasal symptoms before treatment, there was a significant reduction in nasal obstruction, nasal and throat dryness scores as well as nasal bleeding after CPAP therapy. Conclusions: Nasal na pharyngeal symptoms are frequent in OSAS patients. CPAP therapy may originate nasal symptoms in patients previously assymptomatic, as well as reduce the intensity of these symptoms in patients that are previously symptomatic.

Keywords: Obstructive sleep apnea syndrome. Nasal obstruction. Continuous positive airway pressure, compliance.

Objective: To determine the effect that re-education of the thoracic and abdominal muscles has on the respiratory muscle strength of patients with cystic fibrosis evaluated over time at the Cystic Fibrosis Outpatient Clinic of the Universidade Católica de Brasília (Catholic University of Brasília). Methods: The sample consisted of 29 cystic fibrosis patients, characterized based on anthropometric, genetic and bacterial colonization data. The patients were submitted to physical therapy sessions, involving re-education of the respiratory muscles, twice a week for four months. Spirometry, pressure manometry and anthropometry were performed before and after each session. Results: Comparing baselines values to those obtained after physical therapy, increases in maximum inspiratory pressure and maximum expiratory pressure were observed in all patients, those without any obstructive respiratory disease and those with mild obstructive respiratory disease (p < 0.05). A positive correlation between age and maximum expiratory pressure was observed for most of the patients. Maximum inspiratory pressure correlated positively with age only in the group with mild obstructive respiratory disease (p = 0.012; r = 0.817). In female patients and in the group of patients without obstructive respiratory disease, a negative correlation was observed between maximum expiratory pressure and colonization with Pseudomonas aeruginosa (p = 0.036; r = -0.585). Conclusion: Use of the thoracic and abdominal muscle re-education technique increased respiratory muscle strength in the cystic fibrosis patients studied, a finding that underscores the importance of including physical therapy in the treatment of these patients.

Keywords: Cystic fibrosis/rehabilitation; Physical therapy technique; Respiratory muscles; Forced expiratory volume; Inspiratory capacity; Vital capacity

Objective: To analyze the effects of the continuous positive airway pressure (CPAP), with 30% of FiO2 and in compressed air, used during the performance of submaximal physical activity on an ergometric treadmill. Materials and methods: Nine male individuals with COPD were submitted to physical activity on the ergometric treadmill using CPAP with 30% FiO2 .The authors evaluated the behavior of the spirometric parameters, the forced vital capacity (FVC), the forced expiratory volume in the first second (FEV1) before and after physical activity, the respiratory frequency (f), the arterial oxygen saturation (SaO2), the cardiac frequency (cf), the systolic arterial pressure (SAP), and the diastolic arterial pressure (DAP) at rest and during physical activity. Results and conclusion: Results have shown that, when using CPAP in both situations analyzed, there has been an increase in the FVC and a decrease in f and in cf with statistically significant difference (α = 0.05). SaO2 has showned a significantly higher mean when CPAP was used with 30% of FiO2 (α = 0.05). The FEV1, the SAP and DAP have maintained the same value in the statistical analyses.

Keywords: Exercise test. Forced expiratory volume. Vital capacity.

Objective: To use the forced oscillation technique to evaluate asthma patients presenting positive bronchodilator responses (confirmed through spirometry) and compare the results with those obtained in healthy individuals. Methods: The study sample consisted of 53 non-smoking volunteers: 24 healthy subjects with no history of pulmonary disease and 29 asthmatics presenting positive bronchodilator response, as determined through analysis of spirometry findings. All of the subjects were submitted to forced oscillation technique and spirometry immediately before and 20 minutes after the administration of salbutamol spray (300 g). The parameters derived from the forced oscillation technique were total respiratory resistance, total respiratory reactance, resistance extrapolated to the y axis, the slope of resistance, and dynamic compliance. The parameters measured in the spirometry evaluation tests were forced expiratory volume in one second and forced vital capacity. Results: In the control group, bronchodilator use produced a significant alteration in the resistance extrapolated to the y axis (p < 0.001), although no significant differences were observed in the slope of resistance or in dynamic compliance. Analysis of the asthma patients revealed significant differences between the prebronchodilator and postbronchodilator values for all spirometry and forced oscillation technique parameters. Values of p < 0.001 were obtained for all comparisons between the two groups. Conclusion: The modifications provoked by use of the forced oscillation technique were in direct concordance with the pathophysiology of the bronchodilator response in asthma patients, indicating that the forced oscillation technique could be useful as a complement to spirometry in these patients.

Keywords: Asthma; Bronchial hyperreactivity; Spirometry/methods; Bronchial provocation tests; Forced expiratory volume/physiology; Oscillometry

Introduction: Spirometry and analysis of blood gases data have been extensively used to assess ventilatory limitation and prognosis of COPD patients. However, functional physical tests, such as the six-minute walk test (6wt) have been used for the dynamic assessment of COPD patients. Objective: To determine correlations between respiratory function test data and the six-minute walk test in COPD patients. Patients and methods: 45 patients were submitted to clinical history survey and complete physical examination performed by the medical staff of the Pneumology Department of the Brasilia University Hospital, followed by spirometry, analysis of arterial blood gases, maximal respiratory pressures data, and the six-minute walk test. Results: Concerning the spirometric, analysis of blood gases and maximal respiratory pressures data, statistically significant positive correlations (p < 0.05) between FEV1, PaO2, SpO2, MEP and the six-minute walk test were obtained. Conclusions: For the studied group, the six minute walk test has significant correlation with FEV1, PaO2, SpO2 and MEP, and can be used as an alternative functional assessment of COPD patients.