Objective: To evaluate the effect of the association of the breath stacking (BS) technique associated with routine physiotherapy on pulmonary function, lung volumes, maximum respiratory pressures, vital signs, peripheral oxygenation, thoracoabdominal mobility, and pain in the surgical incision in patients submitted to upper abdominal surgery during the postoperative period, as well as to analyze BS safety. Methods: This was a randomized clinical trial involving 34 patients divided into a control group (CG; n = 16), who underwent conventional physiotherapy only, and the BS group (BSG; n = 18), who underwent conventional physiotherapy and BS. Both groups performed two daily sessions from postoperative day 2 until hospital discharge. The primary outcomes were FVC and Vt. The safety of BS was assessed by the incidence of gastrointestinal, hemodynamic, and respiratory repercussions. Results: Although FVC significantly increased at hospital discharge in both groups, the effect was greater on the BSG. Significant increases in FEV1, FEV1/FVC ratio, PEF, and FEF25-75% occurred only in the BSG. There were also significant increases in Ve and Vt in the BSG, but not when compared with the CG values at discharge. MIP and MEP significantly increased in both groups, with a greater effect on the BSG. There was a significant decrease in RR, as well as a significant increase in SpO2 only in the BSG. SpO2 acutely increased after BS; however, no changes were observed in the degree of dyspnea, vital signs, or signs of respiratory distress, and no gastrointestinal and hemodynamic repercussions were observed. Conclusions: BS has proven to be safe and effective for recovering pulmonary function; improving lung volumes, maximum respiratory pressures, and peripheral oxygenation; and reducing respiratory work during the postoperative period after upper abdominal surgery.

Keywords: Abdomen/surgery; Pulmonary ventilation; Physical therapy modalities. (ClinicalTrials.gov identifier: NCT 04418700 [http://www.clinicaltrials.gov/])

Objective: To compare the effects of voluntary breath stacking (VBS) and involuntary breath stacking (IBS) techniques on respiratory mechanics, lung function patterns, and inspiratory capacity in tracheostomized patients. Methods: This was a randomized crossover clinical trial involving 20 tracheostomized patients admitted to the ICU and submitted to the VBS and IBS techniques, in random order, with an interval of 5 h between each. Ten cycles of each technique were performed with an interval of 30 s between each cycle. In VBS, patients performed successive inspirations for up to 30 s through a one-way valve, whereas in IBS, successive slow insufflations were performed with a resuscitator bag until the pressure reached 40 cmH2O. Respiratory mechanics, inspiratory capacity, and the lung function pattern were evaluated before and after the interventions. Results: After IBS, there was an increase in static compliance (p = 0.007), which was also higher after IBS than after VBS (p = 0.03). There was no significant difference between the pre-VBS and post-VBS evaluations in terms of static compliance (p = 0.42). Inspiratory capacity was also greater after IBS than after VBS (2,420.7 ± 480.9 mL vs. 1,211.3 ± 562.8 mL; p < 0.001), as was airway pressure (38.3 ± 2.6 cmH2O vs. 25.8 ± 5.5 cmH2O; p < 0.001). There were no changes in resistance or lung function pattern after the application of either technique. Conclusions: In comparison with VBS, IBS promoted greater inspiratory capacity and higher airway pressure, resulting in an increase in static compliance.

Keywords: Mucociliary clearance; Respiratory care units; Respiratory mechanics; Physical therapy modalities.

Objective: To assess the association between smoking and abdominal fat among male blood donors. Methods: This was a cross-sectional study involving 1,235 adult male blood donors (age, 20-59 years) in the city of Cuiabá, Brazil. Socioeconomic, demographic, and anthropometric data, as well as information on the lifestyle of the participants, were collected. In this study, waist circumference and waist-to-hip ratio were used as markers of abdominal fat. The association between these two markers and smoking was analyzed by multiple linear regression in separate models, adjusted for potential confounders. Results: Of the 1,235 respondents, 273 (22.1%) reported being smokers, and, of those, 99 (36.3%) reported smoking more than 15 cigarettes per day. The average body mass index was lower among smokers than among nonsmokers (p < 0.001). In the multiple linear regression analyses, smoking was associated with waist circumference and waist-to-hip ratio for smokers of 6-10 cigarettes/day and of ≥ 11 cigarettes/day. Conclusions: In our sample, smoking was positively associated with indicators of abdominal fat, regardless of potential confounding factors, including the consumption of alcoholic beverages.

Keywords: Smoking; Obesity; Abdominal fat.

A series of pulmonary complications can occur after abdominal surgery. Therefore, it is necessary to introduce appropriate treatment early in order to minimize postoperative complications. The objective of the present study was to evaluate patients submitted to abdominal surgery in terms of the effect of physical therapy in the immediate postoperative period. This was a randomized clinical trial, in which one group of patients was submitted to physical therapy in the postoperative recovery room and, subsequently, in the infirmary, whereas another group was submitted to physical therapy in the infirmary exclusively. We conclude that physical therapy performed in the immediate postoperative period minimizes losses in lung function and respiratory muscle strength, as well as shortening recovery room stays.

Keywords: Physical therapy (specialty); Postoperative period; Surgery/abdomen.

Objective: To evaluate cough efficiency using two manually-assisted cough techniques. Methods: We selected 28 patients with Duchenne muscular dystrophy. The patients were receiving noninvasive nocturnal ventilatory support and presented FVC values < 60% of predicted. Peak cough flow (PCF) was measured, with the patient seated, at four time points: at baseline, during a spontaneous maximal expiratory effort (MEE); during an MEE while receiving chest compression; during an MEE after air stacking with a manual resuscitation bag; and during an MEE with air stacking and compression (combined technique). The last three measurements were conducted in random order. The results were compared using Pearson's correlation test and ANOVA with repeated measures, followed by Tukey's post-hoc test (p < 0.05). Results: The mean age of the patients was 20 ± 4 years, and the mean FVC was 29 ± 12%. Mean PCF at baseline, with chest compression, after air stacking and with the use of the combined technique was 171 ± 67, 231 ± 81, 225 ± 80, and 292 ± 86 L/min, respectively. The results obtained with the use of the combined technique were significantly better than were those obtained with the use of either technique alone (F[3.69] = 67.07; p < 0.001). Conclusions: Both chest compression and air stacking techniques were efficient in increasing PCF. However, the combination of these two techniques had a significant additional effect (p < 0.0001).

Keywords: Muscular dystrophy, Duchenne; Intermittent positive-pressure ventilation; Cough; Insufflation;Peak expiratory flow rate.

Introduction: Smoking is the major preventable risk of morbidity and mortality. However, its prevalence is high in developed countries and increasing in developing countries, even though its effects are now better known. The purpose of this study was to compare the exhaled carbon monoxide concentration (exCO) between smokers and nonsmokers, evaluate the factors that influence this parameter among smokers and the potential influence of passive smoking by measuring exCO in workers and patients of Instituto do Coração HC-FMUSP. Materials and methods: This cross study included 256 volunteers who responded to a questionnaire and were submitted to exCO measuring with the MicroCo meter device. Results: There were 106 males and 150 females. Mean age was 43.4 years (Vmin-max: 15-83). There were 107 smokers, 118 nonsmokers and 31 passive smokers. Mean exCO was 14.01 ppm (Vmin-max: 1-44) among smokers, 2.03 ppm (Vmin-max: 0-5) among passive smokers and 2.50 ppm (Vmin-max: 0-9) among nonsmokers. Significant statistical difference was observed between smokers and the other groups (p < 0.001), but not between nonsmokers and passive smokers. A positive correlation was found between the number of cigarettes smoked per day and exCO values while there was a negative correlation between the exCO values and the timing of the last cigarette. For a reference limit value of 6 ppm, sensitivity was 70% and specificity was 96%. Conclusion: exCO metering is easy to perform, low-cost, noninvasive and allows the obtention of immediate results and the reference limit value of 6 ppm has good specificity to evaluate the smoking habit.

Keywords: Smoking. Carbon monoxide. Tobacco smoke pollution. Brazil.

Objective: To evaluate whether the exhaled breath temperature (EBT), measured by a noninvasive method, is an effective means of monitoring patients with uncontrolled asthma. Methods: A pilot study comprising nine patients (seven women and two men; mean age: 39 years) diagnosed with asthma at least one year prior to the beginning of the study and not having been under maintenance therapy for the last three months. In the first visit, the patients underwent spirometry and measurement of EBT. The patients were then instructed to use inhaled budesonide/formoterol (200/6 µg) every 12 h for six weeks. In addition, the patients with severe asthma (FEV1 < 60% of predicted) were instructed to use oral prednisolone (40 mg/day) for five days. After six weeks, the patients underwent the same tests. Results: All of the patients reported an improvement in the symptoms of asthma, as confirmed by a statistically significant increase in FEV1 from the first to the second visit (mean, 56.1% vs. 88.7% of predicted; p < 0.05). Five patients used oral prednisolone for the first five days of the treatment period. Six patients used additional doses of inhaled budesonide/formoterol (mean duration, 2.5 weeks). The EBT decreased significantly from the first to the second visit (mean EBT: 35.1°C vs. 34.1°C; p < 0.05). Conclusions: Uncontrolled asthma, especially during exacerbations, is followed by an increase in EBT, which decreases after appropriate asthma control, as demonstrated by an increase in FEV1 and an improvement of the reported symptoms. These preliminary results suggest that EBT can be used as a parameter for the assessment of asthma control.

Keywords: Asthma; Biomarkers, pharmacological; Hydroxycorticosteroids.

In recent years, the analysis of exhaled breath condensate samples has been given great weight as a noninvasive methodology of studying physiology and lung diseases. The present study describes a device for measuring exhaled breath condensate that is affordable, easily constructed, portable and suitable for use in the field, as well as allowing the collection of simultaneous samples. The results obtained with this device in terms of the concentrations of pH, hydrogen peroxide and nitrite, metabolites related to inflammatory and oxidative damage, in exhaled breath condensate samples are comparable to those obtained with other devices previously described.

Keywords: Exhalation; Lung diseases; Equipment design.

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: Respiratory complications are the main causes of morbidity and mortality in patients with neuromuscular disease (NMD). The objectives of this study were to determine the effects that routine daily home air-stacking maneuvers have on pulmonary function in patients with spinal muscular atrophy (SMA) and in patients with congenital muscular dystrophy (CMD), as well as to identify associations between spinal deformities and the effects of the maneuvers. Methods: Eighteen NMD patients (ten with CMD and eight with SMA) were submitted to routine daily air-stacking maneuvers at home with manual resuscitators for four to six months, undergoing pulmonary function tests before and after that period. The pulmonary function tests included measurements of FVC; PEF; maximum insufflation capacity (MIC); and assisted and unassisted peak cough flow (APCF and UPCF, respectively) with insufflations. Results: After the use of home air-stacking maneuvers, there were improvements in the APCF and UPCF. In the patients without scoliosis, there was also a significant increase in FVC. When comparing patients with and without scoliosis, the increases in APCF and UPCF were more pronounced in those without scoliosis. Conclusions: Routine daily air-stacking maneuvers with a manual resuscitator appear to increase UPCF and APCF in patients with NMD, especially in those without scoliosis.

Keywords: Neuromuscular diseases; Cough; Respiratory function tests; Respiratory therapy.

Objective: To assess respiratory system impedance (Zrs) and spirometric parameters in children and adolescents with and without a history of preterm birth. Methods: We evaluated a sample of 51 subjects between 11 and 14 years of age: 35 who had a history of preterm birth (preterm group) and 16 who had been born at term (full-term group). Lung function was measured by spirometry, spectral oscillometry, and intra-breath oscillometry. Results: Neither spirometry nor spectral oscillometry revealed any statistically significant differences between the preterm and full-term groups. However, intra-breath oscillometry demonstrated significant differences between the two groups in terms of the change in resistance, reactance at end-inspiration, and the change in reactance (p < 0.05 for all). Conclusions: Our findings suggest that abnormalities in Zrs persist in children and adolescents with a history of preterm birth and that intra-breath oscillometry is more sensitive than is spectral oscillometry. Larger studies are needed in order to validate these findings and to explore the impact that birth weight and gestational age at birth have on Zrs later in life.

Keywords: Oscillometry; Premature birth; Respiratory function tests; Respiratory mechanics; Spirometry.

Objective: To investigate the reliability, internal consistency and validity of the Brazilian Portuguese version of the University of California San Diego Shortness of Breath Questionnaire (UCSD SOBQ) in patients with interstitial lung disease (ILD). Methods: Patients with ILD completed the questionnaire at three different time points, one week apart, with the assistance of two independent assessors. Intra- and inter-rater reliability were analysed via the intraclass correlation coefficient (ICC). Internal consistency was assessed with the Cronbach's alpha coefficient. For the validity analysis, associations between variables were assessed with Spearman's or Pearson's correlation coefficient. Results: Thirty patients with ILD (idiopathic pulmonary fibrosis, connective tissue disease-associated pulmonary fibrosis, sarcoidosis, asbestosis or non-specific interstitial pneumonia) were included (15 men; mean age, 59 ± 10 years; DLCO: 46 [33-64] % predicted). UCSD SOBQ scores showed excellent agreement and internal consistency in the intra-rater analysis (ICC: 0.93 [0.85-0.97]; Cronbach alpha: 0.95) and in the inter-rater analysis (ICC: 0.95 [0.89-0.97]; Cronbach alpha: 0.95), as well as correlating significantly with dyspnoea (as assessed by the Medical Research Council scale; r = 0.56); Medical Outcomes Study 36-item Short-Form Health Survey domains bodily pain, general health, vitality and physical functioning (-0.40 = r = -0.74); six-minute walk distance (r = -0.38); and quadriceps muscle strength (r = -0.41). Conclusions: The Brazilian Portuguese version of the UCSD SOBQ is valid, is reliable and has internal consistency in patients with ILD in Brazil.

Keywords: Lung diseases, interstitial; Dyspnea; Surveys and questionnaires.