Pleural empyema carries high morbidity and mortality rates. Therapy focuses on the control of the infectious process in its initial phase when parenteral antibiotics and chest drainage are likely to be most effective. The ability of dextrans in preventing peritoneal adhesions leads one to test their potential effectiveness in reducing fibrinous proliferation in a rat model of pleural empyema. Twenty-four Wistar rats weighing 250-400 grams were anesthetized, submitted to a right thoracotomy and then randomized into 3 groups (n = 8 each). Animals in group I were given intrapleural dextran 40 (1 ml/kg) + 1 ml/kg of Staphylococcus aureus extract (1010 cells/ml) in heart-brain culture media obtained from oropharyngeal swabs of the animals. Animals in group II received saline solution (1 ml/kg) +1 ml/kg of Staphylococcus aureus extract (1010 cells/ml) in heart-brain culture media. Animals in group III (controls) were given the culture media without bacteria (1 ml/kg) in addition to saline (1 ml/kg). Upon completion, the chest was deaired, the thoracotomy wound was closed, the animals recovered, observed for 4 days, and sacrificed. Only the animals in groups I and II developed pleural effusion and empyema (average volume of 9.7 ml and 8.1 ml respectively, p > 0.05, NS). There was a significant weight loss in groups I and II compared to control animals (p = 0.004). There were no significant differences in blood work-up tests between groups. The pleural fluid of all animals in groups I and II had positive cultures for Staphylococcus aureus. The biochemical analysis of the pleural fluid in animals from groups I and II did not show any significant differences. The authors concluded that in this novel and reliable model of pleural empyema in rats, the intrapleural administration of dextran 40 at time of inoculation of bacteria did not result in any measurable reduction of the pleural reaction after 96 hours of observation.

Keywords: Empyema. Pleura. Rat. Dextrans. Staphylococcus.

Objective: To determine the efficacy of thoracoscopy in the management of children with complicated parapneumonic pleural effusion at the fibrinopurulent stage. Methods: Retrospective study of 99 children submitted to thoracoscopy for the treatment of complicated parapneumonic pleural effusion at the fibrinopurulent stage between November of 1995 and July of 2005. The mean age was 2.6 years (range, 0.4-12 years), and 60% were males. Thoracoscopy was performed at three different hospitals following the same treatment algorithm. Results: Thoracoscopy was effective for 87 children (88%). In 12 (12%), a second surgical procedure was required: another thoracoscopy (n = 6) or thoracotomy/thoracostomy (n = 6). Mean duration of chest tube drainage following successful thoracoscopy was 3 days vs. 10 days in patients submitted to a second procedure (p < 0.001). In all of the children, the pleural infection resolved after treatment. Thoracoscopy-related complications included air leak (30%), chest tube bleeding (12%), subcutaneous emphysema associated with trocar insertion (2%) and surgical wound infection (2%). None of the children required additional surgical procedures due to the complications. Conclusions: The effectiveness of thoracoscopy in children with parapneumonic pleural effusion at the fibrinopurulent stage was 88%. The procedure was safe, with a low rate of severe complications. Thoracoscopy should be the first-choice treatment for children with parapneumonic pleural effusion at the fibrinopurulent stage.

Keywords: Thoracoscopy; Pleural effusion; Empyema, pleural.

Objective: To evaluate the results of thoracoscopy for the treatment of pleural empyema in pediatric patients. Methods: A retrospective study of 117 patients who underwent mediastinoscopy or video-assisted thoracoscopy for pleural empyema treatment. General anesthesia and single-lumen oral intubation were used. Surgery was indicated when there was pleural effusion and no clinical and radiological response to clinical treatment (antibiotics, physiotherapy and thoracocentesis) or severe sepsis, together with loculated pleural effusion (confirmed through ultrasound or computed tomography of the chest). Results: Between February of 1983 and July of 2006, 117 thoracoscopies were performed in patients ranging in age from 5 months to 17 years (mean, 4 years). Mean time for thoracic drainage was 9 days (range, 2-33 days), and mean period of hospitalization was 16.4 days (range, 4 to 49 days). One patient (0.8%) died after surgery, and persistent fistula was observed in 33 patients (28%). In 7 cases (6%), open thoracotomy with pulmonary decortication was performed due to the disposition of the empyema. Conclusions: Management of pleural empyema in this age bracket is still controversial, and surgical indication is often delayed, particularly when there are multiple loculations or severe sepsis. Early thoracoscopy yields a better clinical outcome for pediatric patients with pleural empyema, with apparent decreased morbidity and mortality, earlier chest tube removal, earlier hospital discharge and improved response to antibiotic therapy.

Keywords: Empyema, pleural; Pediatrics/instrumentation; Thoracoscopy; Thoracic surgery, video-assisted.

Some techniques used in respiratory therapy are not based on sound scientific evidence. The misuse of such techniques can be harmful in terms of adverse effects and may not be cost-effective. A systematic review of the literature was performed using the Oldmedline, Medline, Cinahl and Lilacs databases, as well as the registry of clinical trials registered by the Cochrane Library and National Institutes of Health. The focus of the review was on trials addressing the efficacy of respiratory therapy in treating pleural empyema in children, adolescents and adults. No such trials were found. We can conclude that there is a lack of data regarding the efficacy of respiratory therapy in pleural empyema. In order to provide such data, clinical trials are warranted.

Keywords: Empyema pleural/rehabilitation; Evidence-based medicine; Physical therapy techniques; Review [Publication Type]; Randomized controlled trials

Objective: To investigate the effects of maternal protein malnutrition during lactation on the elastic fibers in the tracheas of Wistar rat pups. Methods: At delivery, 12 male pups of two Wistar rat dams were equally divided into two groups: control, in which the dam received water and standard rat chow ad libitum during lactation; and protein-restricted (PR), in which the dam received water ad libitum and an isoenergetic PR diet (8% protein). At 21 days of age, the pups were killed and their tracheas were excised. The elastic fibers were stained with Weigert's resorcin-fuchsin (after oxidation) and evaluated under light microscopy. Morphometric determinations were performed by stereology, with the point-counting method, and expressed as volumetric densities. Results: Elastic fibers, most having a longitudinal distribution, were identified beneath the tracheal mucosa. In addition, well-defined circular layers of elastic fibers were found around the inner and outer surfaces of the cartilaginous ring. There were no differences between the groups regarding the organization and distribution of the elastic fibers. The volumetric density of the elastic fibers of the pups in the control and PR groups was 2.46 ± 0.99% and 3.25 ± 1.13%, respectively (p < 0.01). Conclusions: The volumetric density of elastic fibers appears to be greater in rat pups breastfed by dams receiving a PR diet than in those breastfed by dams receiving a normal diet.

Keywords: Trachea/growth and development; Trachea/anatomy and histology; Extracellular matrix; Airway remodeling; Malnutrition.

Objective: To compare histopathological findings and the degree of apoptosis among rat lungs preserved with low-potassium dextran (LPD) solution, histidine-tryptophan-ketoglutarate (HTK) solution, or normal saline (NS) at two ischemia periods (6 h and 12 h) using an experimental rat model of ex vivo lung perfusion. Methods: Sixty Wistar rats were anesthetized, randomized, and submitted to antegrade perfusion via pulmonary artery with one of the preservation solutions. Following en bloc extraction, the heart-lung blocks were preserved for 6 h or 12 h at 4°C and then reperfused with homologous blood for 60 min in an ex vivo lung perfusion system. At the end of the reperfusion, fragments of the middle lobe were extracted and processed for histopathological examination. The parameters evaluated were congestion, alveolar edema, alveolar hemorrhage, inflammatory infiltrate, and interstitial infiltrate. The degree of apoptosis was assessed using the TdT-mediated dUTP nick end labeling method. Results: The histopathological examination showed that all of the lungs preserved with NS presented alveolar edema after 12 h of ischemia. There were no statistically significant differences among the groups in terms of the degree of apoptosis. Conclusions: In this study, the histopathological and apoptosis findings were similar with the use of either LPD or HTK solutions, whereas the occurrence of edema was significantly more common with the use of NS.

Keywords: : Organ preservation; Organ preservation solutions; Lung transplantation; Reperfusion injury; Apoptosis.

Objective: To present a model of prostaglandin I2 (PGI2) administration (inhaled vs. parenteral) and to assess the functional performance of the lungs in an ex vivo lung perfusion system. Methods: Forty Wistar rats were anesthetized and placed on mechanical ventilation followed by median sterno-laparotomy and anticoagulation. The main pulmonary artery was cannulated. All animals were maintained on mechanical ventilation and were randomized into four groups (10 rats/group): inhaled saline (IS); parenteral saline (PS); inhaled PGI2 (IPGI2); and parenteral PGI2 (PPGI2). The dose of PGI2 used in the IPGI2 and PPGI2 groups was 20 and 10 µg/kg, respectively. The heart-lung blocks were submitted to antegrade perfusion with a low potassium and dextran solution via the pulmonary artery, followed by en bloc extraction and storage at 4°C for 6 h. The heart-lung blocks were then ventilated and perfused in an ex vivo lung perfusion system for 50 min. Respiratory mechanics, hemodynamics, and gas exchange were assessed. Results: Mean pulmonary artery pressure following nebulization decreased in all groups (p < 0.001), with no significant differences among the groups. During the ex vivo perfusion, respiratory mechanics did not differ among the groups, although relative oxygenation capacity decreased significantly in the IS and PS groups (p = 0.04), whereas mean pulmonary artery pressure increased significantly in the IS group. Conclusions: The experimental model of inhaled PGI2 administration during lung extraction is feasible and reliable. During reperfusion, hemodynamics and gas exchange trended toward better performance with the use of PGI2 than that with the use of saline.

Keywords: Prostaglandins; Lung transplantation; Reperfusion; Models, animal; Rats.

Liquid perfluorocarbon (PFC) instillation has been studied experimentally as an adjuvant therapy in the preservation of lung grafts during cold ischemia. The objective of this study was to evaluate whether vaporized PFC is also protective of lung grafts at different cold ischemia times. We performed histological analysis of and measured oxidative stress in the lungs of animals that received only preservation solution with low-potassium dextran (LPD) or vaporized PFC together with LPD. We conclude that vaporized PFC reduces the production of free radicals and the number of pulmonary structural changes resulting from cold ischemia.

Keywords: Ischemia; Reperfusion; Fluorocarbons; Lung transplantation; Oxidative stress.

Objective: Mometasone furoate (MF) is a new potent synthetic inhaled corticosteroid. Internationally, MF is administered via a dry-powder inhaler that contains multiple doses. As a preparation that would be more cost-effective, single-dose MF capsules were developed in Brazil. The objective of the present study was to evaluate the efficacy and safety of the two inhalers for MF administration in patients with asthma. Methods: A randomized, multicenter, open-label, parallel-group clinical trial involving 74 adult patients with moderate persistent asthma who were randomized into two groups to receive approximately 400 µg of MF once a day for 60 days, either via the multiple-dose inhaler or via the newly developed single-dose inhaler. Results: No significant differences were observed between the two groups regarding the primary endpoints (FEV1 and rescue medication use) or the secondary endpoints (morning PEF, tolerability, and safety, the last as assessed on the basis of hypothalamic-pituitary-adrenal axis function). Conclusions: The use of the single-dose inhaler developed in Brazil for MF administration is as effective and safe as is that of a standard inhaler in the treatment of patients with asthma. Keywords: Anti-asthmatic agents; Pregnadienediols; Metered dose inhalers.

Keywords: Anti-asthmatic agents; Pregnadienediols; Metered dose inhalers. (ClinicalTrials.gov identifier: NCT00975741 [http://www.clinicaltrials.gov/])

Background: Empyema is a serious disease classically characterized by purulence within the pleural cavity. Early diagnosis demands immediate treatment, although there is still great controversy surrounding the question of what is the best therapy. Objective: To analyze the method of using thoracentesis and pleural irrigation, combined with the intrapleural application of an antimicrobial agent, to treat empyema - and to compare this method with others described in the literature. Method: Between January 1999 and May 2000, 17 patients diagnosed with loculated or diffuse pleural empyema were submitted to thoracentesis, followed by thorough washing of the pleural cavity with isotonic solution and intrapleural administration of a non-irritating antimicrobial agent to the pleura. Results: The group of patients studied consisted of 15 men and 2 women, and the average age was 44. The most common clinical symptoms were fever, productive cough, chest pain and dyspnea, and the most common cause was pneumonia. Macroscopically, 12 patients presented obviously purulent pleural fluid. In 4 (26.67%) of the patients, the etiological agent was identified, the most frequent being Staphylococcus sp. Pulmonary decortication was indicated in 2 cases, and those 2 patients were therefore excluded. The average length of hospitalization was 17.1 days, although 3 patients received the treatment as outpatients. No recurrence or mortality was observed with the use of this methodology. Conclusion: This approach reduced the need for invasive procedures, proving to be safe and efficient, with lower rates of morbidity and mortality than other modalities of treatment.

Keywords: Empyema/Pleural, Pleura/Blood Supply, Treatment Outcome, Treatment Effectiveness.

Introduction: Most of the experimental studies on amiodarone-induced pulmonary toxicity have been performed in male Fischer-344 rats. Objective: To investigate the effect of amiodarone on body weight and on lung morphological and cytopathologic parameters in both genders of other rat strains. Methods: Groups of male and female Wistar, Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats received, 175 mg/kg/day of amiodarone suspended in saline by gavage for four weeks. Controls received saline alone. Body weight gain, total cellularity, and differential of the bronchoalveolar lavage (BAL) and lung histopathology were studied. Results: Mortality due to amiodarone was observed in treated WKY rats, mostly in males. Treated male and female SHR animals had less body weight gain among all strains studied. Male Wistar and SHR treated rats presented more body weight gain than females of the respective strains. BAL of treated SHR rats were hemorrhagic. BAL cellularity was higher in treated males (WKY > Wistar > SHR). In WKY males and females, however, the differential count showed a lesser percent of macrophages and higher of neutrophils than in the other strains. BAL macrophages of treated Wistar rats presented phospholipidosis, whereas most macrophages of treated SHR rats were normal. In lung anatomicopathologic examination, no difference was found related to gender and no pneumonitis was observed. In Wistar rats, the examination was characterized by a marked quantity of intra-alveolar "foamy" macrophages, numerous intraparenchymal abscesses were found in WKY rats, and alveolar hemorrhage was present in SHR rats. Conclusions: 1) amiodarone induces more foamy macrophages in Wistar rats than in the WKY and SHR strains, although they do not develop pneumonitis in the model used; 2) amiodarone has greater effect on lung morphological and cytopathologic parameters of male rats.

Small animal models are particularly suitable for lung preservation studies, because they are simple and cost-effective. This brief communication focuses on the technical description of an ex vivo lung perfusion model in rats by means of a commercially available apparatus, which was the first to be installed in a thoracic surgery research laboratory in Brazil. The model and its preparation, together with its applications for lung preservation studies, are described in detail. All technical details can also be seen in a video posted on the website of the Brazilian Journal of Pulmonology.

Keywords: Lung transplantation; Reperfusion injury; Rats; Models, animal.

Objective: To describe a new murine model of cigarette smoke-induced emphysema. Methods: Twenty-four male Wistar rats were divided into two groups: the cigarette smoke group, comprising 12 rats exposed to smoke from 12 commercial filter cigarettes three times a day (a total of 36 cigarettes per day) every day for 30 weeks; and the control group, comprising 12 rats exposed to room air three times a day every day for 30 weeks. Lung function was assessed by mechanical ventilation, and emphysema was morphometrically assessed by measurement of the mean linear intercept (Lm). Results: The mean weight gain was significantly (approximately ten times) lower in the cigarette smoke group than in the control group. The Lm was 25.0% higher in the cigarette smoke group. There was a trend toward worsening of lung function parameters in the cigarette smoke group. Conclusions: The new murine model of cigarette smoke-induced emphysema and the methodology employed in the present study are effective and reproducible, representing a promising and economically viable option for use in studies investigating the pathophysiology of and therapeutic approaches to COPD.

Keywords: Tobacco smoke pollution; Emphysema; Disease models, animal; Equipment and supplies.

Objective: To identify how pediatric surgeons manage children with pneumonia and parapneumonic pleural effusion in Brazil. Methods: An online cross-sectional survey with 27 questions was applied to pediatric surgeons in Brazil through the Brazilian Association of Pediatric Surgery. The questionnaire had questions about type of treatment, exams, hospital structure, and epidemiological data. Results: A total of 131 respondents completed the questionnaire. The mean age of respondents was 44 ± 11 years, and more than half (51%) had been practicing pediatric surgery for more than 10 years. The majority of respondents (33.6%) reported performing chest drainage and fibrinolysis when facing a case of fibrinopurulent parapneumonic pleural effusion. A preference for video-assisted thoracic surgery instead of chest drainage plus fibrinolysis was noted only in the Northeast region. Conclusions: Chest drainage plus fibrinolysis was the treatment adopted by most of the respondents in this Brazilian sample. There was a preference for large drains; in contrast, smaller drains were preferred by those who perform chest drainage plus fibrinolysis. Respondents would rather change treatment when facing treatment failure or in critically ill children.

Keywords: Empyema, pleural; Thoracic surgery, video-assisted; Fibrinolysis; Surveys and questionnaires; Pediatric surgery .

Objective: To determine the incidence of residual pneumothorax after video-assisted thoracic sympathectomy, with and without postoperative pleural drainage, and to evaluate the possible influence of this type of pneumothorax on postoperative pain within the first 28 postoperative days. Methods: All patients presenting symptoms consistent with primary palmoplantar hyperhidrosis and treated at the Thoracic Surgery Outpatient Clinic of the State Hospital of Sumaré between July and December of 2006 were included. All were submitted to sympathectomy up to the third ganglion using video-assisted thoracoscopy and were randomized to receive or not receive postoperative pleural drainage for 3 h. Chest X-rays and low-dose computed tomography scans of the chest were performed on the first postoperative day in order to determine the incidence of residual pneumothorax. At different time points up to postoperative day 28, patient pain was assessed using a visual numeric scale and by measuring the quantity of opioid analgesics required. Results: This study comprised 56 patients, 27 submitted to bilateral pleural drainage and 29 not submitted to drainage. There was no statistical difference between the two groups in terms of the incidence of post-sympathectomy residual pneumothorax. Residual pneumothorax diagnosed through any of the methods did not influence pain within the first 28 postoperative days. Conclusion: Performing closed pleural drainage for 3 h immediately after video-assisted thoracic sympathectomy did not affect lung re-expansion or the incidence of residual pneumothorax. When residual pneumothorax was present, it did not affect pain within the first 28 postoperative days.

Keywords: Hyperhidrosis; Sympathectomy; Pain, postoperative; Pneumothorax; Drainage; Pleura.

Objective: To evaluate the role of intrapleural positioning of a pleural catheter in early lung expansion and pleurodesis success in patients with recurrent malignant pleural effusion (RMPE). Methods: This was a retrospective study nested into a larger prospective cohort study including patients with RMPE recruited from a tertiary university teaching hospital between June of 2009 and September of 2014. The patients underwent pleural catheter insertion followed by bedside pleurodesis. Chest CT scans were performed twice: immediately before pleurodesis (iCT) and 30 days after pleurodesis (CT30). Catheter positioning was categorized based on iCT scans as posterolateral, anterior, fissural, and subpulmonary. We used the pleural volume on iCT scans to estimate early lung expansion and the difference between the pleural volumes on CT30 and iCT scans to evaluate radiological success of pleurodesis. Clinical pleurodesis success was defined as no need for any other pleural procedure. Results: Of the 131 eligible patients from the original study, 85 were included in this nested study (64 women; mean age: 60.74 years). Catheter tip positioning was subpulmonary in 35 patients (41%), anterior in 23 (27%), posterolateral in 17 (20%), and fissural in 10 (12%). No significant differences were found among the groups regarding early lung expansion (median residual pleural cavity = 377 mL; interquartile range: 171-722 mL; p = 0.645), radiological success of pleurodesis (median volume = 33 mL; interquartile range: −225 to 257 mL; p = 0.923), and clinical success of pleurodesis (85.8%; p = 0.676). Conclusions: Our results suggest that the position of the tip of the pleural catheter influences neither early lung expansion nor bedside pleurodesis success in patients with RMPE.

Keywords: Pleurodesis; Pleural effusion, malignant; Tomography; Catheters.