The importance of endobag use with incision-protective devices in VATS lung resection: a preliminary study.

OBJECTIVE: The advent of new techniques such as video-assisted thoracoscopic surgery (VATS) for the removal of lung segments leads to compression of the surgical specimen, with the possible dissemination of neoplastic cells. The sheer volume of surgeries performed using these techniques has caused many institutions to stop removing the surgical specimen using an endobag, even when retractors/protectors are used in the instrumentalization incision. This study aimed to collect data from patients undergoing lung resection by VATS and analyze the cytopathological results of the collected material. RESULTS: A total of 47 endobag fluid samples were collected from patients who underwent VATS. The surgical specimen was subjected to histopathological analysis, and all patients underwent pathological TNM staging. In the cytopathological analyses, only 2 (4.3%) specimens of endobag fluid aspirate were positive for neoplastic cells. In these two cases, the tumors were peripheral, both with diagnoses of moderately differentiated adenocarcinoma and with classifications of T1bN0M0 and T3N0M0. These results indicate that although there is a low incidence of tumor cells in endobag fluid, it is always better to perform surgery using all available protective measures to avoid tumor implantation in the thoracic cavity to the greatest extent possible.

Solid Indeterminate Nodules with a Radiological Stability Suggesting Benignity: A Texture Analysis of Computed Tomography Images Based on the Kurtosis and Skewness of the Nodule Volume Density Histogram.

BACKGROUND: The number of incidental findings of pulmonary nodules using imaging methods to diagnose other thoracic or extrathoracic conditions has increased, suggesting the need for in-depth radiological image analyses to identify nodule type and avoid unnecessary invasive procedures. OBJECTIVES: The present study evaluated solid indeterminate nodules with a radiological stability suggesting benignity (SINRSBs) through a texture analysis of computed tomography (CT) images. METHODS: A total of 100 chest CT scans were evaluated, including 50 cases of SINRSBs and 50 cases of malignant nodules. SINRSB CT scans were performed using the same noncontrast enhanced CT protocol and equipment; the malignant nodule data were acquired from several databases. The kurtosis (KUR) and skewness (SKW) values of these tests were determined for the whole volume of each nodule, and the histograms were classified into two basic patterns: peaks or plateaus. RESULTS: The mean (MEN) KUR values of the SINRSBs and malignant nodules were 3.37 ± 3.88 and 5.88 ± 5.11, respectively. The receiver operating characteristic (ROC) curve showed that the sensitivity and specificity for distinguishing SINRSBs from malignant nodules were 65% and 66% for KUR values >6, respectively, with an area under the curve (AUC) of 0.709 (p < 0.0001). The MEN SKW values of the SINRSBs and malignant nodules were 1.73 ± 0.94 and 2.07 ± 1.01, respectively. The ROC curve showed that the sensitivity and specificity for distinguishing malignant nodules from SINRSBs were 65% and 66% for SKW values >3.1, respectively, with an AUC of 0.709 (p < 0.0001). An analysis of the peak and plateau histograms revealed sensitivity, specificity, and accuracy values of 84%, 74%, and 79%, respectively. CONCLUSIONS: KUR, SKW, and histogram shape can help to noninvasively diagnose SINRSBs but should not be used alone or without considering clinical data.

Edema pulmonar de reexpansão na doença pleural / Re-expansion pulmonary edema in pleural disease

O edema pulmonar de reexpansão é uma condição clínica rara, porém frequentemente letal. É uma complicação secundária à rápida reexpansão do pulmão colapsado em consequência a um pneumotórax ou derrame pleural de grande volume. São de fundamental importância para sua prevenção, o conhecimento da etiopatogenia e a execução de técnica adequada na drenagem pleural tubular e na toracocentese. A sua patogênese é multifatorial. O esvaziamento lento da cavidade pleural, a monitorização da oximetria e administração de oxigênio são necessários para prevenção e tratamento. AU

The reexpansion pulmonary edema (RPE) is a rare clinical condition, but often lethal. It is a secondary complication to the rapid re-expansion of the lung collapsed as a result of a pneumothorax or pleural effusion of large volume. The fundamental importance for prevention are knowledge of the pathogenesis and executing proper technique on pleural drainage and thoracentesis. Its pathogenesis is multifactorial. Its prevention is still based on slow pleuralemptying procedures, without standards to avoid RPEevolution. The oximetry monitoring and administration of oxygen are needed for treatment. AU

Lung cancer with chest wall invasion: retrospective analysis comparing en-bloc resection and 'resection in bird cage'.

BACKGROUND: Invasion of the chest wall per se is not a contraindication for tumor resection in non-small cell lung cancer (NSCLC), provided there is no mediastinal lymph node or vital structure involvement. Although widely known to Brazilian surgeons, the 'resection in bird cage' technique has never been widely studied in terms of patient survival. Thus, the objective of this study was to evaluate the postoperative consequences and overall survival of extra-musculoperiosteal resection compared with en-bloc resection in NSCLC patients with invasion of the endothoracic fascia. METHODS: Between January 1990 and December 2009, 33 NSCLC patients with invasion of the thoracic wall who underwent pulmonary resection were retrospectively analyzed. Of the 33 patients evaluated, 20 patients underwent en-bloc resection and 13 underwent 'resection in bird cage.' For each patient, a retrospective case note review was made. RESULTS: The median age at surgery, gender, indication, rate of comorbidities, tumor size and the degree of uptake in the costal margin were similar for both groups. The rate of postoperative complications and the duration of hospitalization did not differ between the groups. Regarding the outcome variables, the disease-free interval, rate of local recurrence, metastasis-free time after surgery, overall mortality rate, mortality rate related to metastatic disease, duration following surgery in which deaths occurred, and overall survival were also similar between groups. The cumulative survival curves between the 'resection in bird cage' and en-bloc resection and between stages Ia + Ib and IIb + IIIa + IV were not significantly different (p = 0.68 and p = 0.64, respectively). The cumulative metastasis-free survival curves were not significantly different between the two types of surgery (p = 0.38). CONCLUSIONS: In NSCLC patients with invasion of the endothoracic fascia, 'resection in bird cage' is a less aggressive procedure that yields similar results in terms of morbidity and mortality compared with en-bloc resection. Thus, 'resection in bird cage' meets the oncologic principles of resection and does not adversely affect the patients in terms of cure.

The surprising outcome of a giant primary mediastinal synovial sarcoma treated with neoadjuvant chemotherapy.

There are only a few cases of primary mediastinal synovial sarcoma in the literature. Normally, they do not respond well to chemotherapy. In our case, a 30-year-old patient was admitted due to thoracic pain, dyspnea, orthopnea, cough, hoarseness and weight loss over a 3-month period as well as a dramatic worsening a week before the admission. A chest radiography showed a completely white left hemithorax and contralateral mediastinal shift; in addition, a chest tomography revealed a giant heterogeneous mediastinal mass, lung atelectasia and a small pleural effusion. The patient was submitted to Chamberlain procedure (biopsy) under local anesthesia and the diagnosis of a synovial sarcoma was obtained after immunohistochemical analysis. Due to his poor general condition, he received chemotherapy first, with a dramatic response, after what, the mass that had been reduced was removed surgically. After a 5-year- follow-up period there are no signs of disease recurrence.

Results and complications of CT-guided transthoracic fine-needle aspiration biopsy of pulmonary lesions.

OBJECTIVE: To analyze the cytological findings of CT-guided percutaneous fine-needle aspiration biopsies of the lung, to demonstrate the diagnostic feasibility of the method in the investigation of pulmonary lesions, and to determine the complications of the procedure, evaluating its safety. METHODS: A retrospective analysis of 89 patients with various types of pulmonary lesions who underwent 97 procedures over a period of five years. The patients were divided into groups regarding the indication for the procedure: suspicion of primary lung cancer (stages IIIB or IV); suspicion of lung cancer (stages I, II, or IIIA) and clinical contraindications for surgery; suspicion of pulmonary metastasis from other organs; and pulmonary lesions with benign radiological aspect. All of the procedures were performed with 25-gauge needles and were guided by spiral CT. The final diagnosis was confirmed by surgical biopsy and clinical/oncological follow-up. For the analysis of complications, the total number of procedures was considered. RESULTS: The main indication for the procedure was suspicion of advanced-stage primary lung cancer. The accuracy of the method for malignant lesions was 91.5%. The lesion was confirmed as cancer in 73% of the patients. The major complication was pneumothorax (27.8%), which required chest tube drainage in 12.4% of the procedures. CONCLUSIONS: The principal indication for CT-guided fine-needle biopsy was suspicion of primary lung cancer in patients who were not surgical candidates. The procedure has high diagnostic feasibility for malignant pulmonary diseases. The most prevalent complication was pneumothorax. However, in most cases, chest tube drainage was unnecessary. No deaths were related to the procedure.

Biópsia aspirativa transtorácica por agulha fina guiada por TC de lesões pulmonares: resultados e complicações / Results and complications of CT-guided transthoracic fine-needle aspiration biopsy of pulmonary lesions

OBJETIVO: Analisar os resultados citológicos de biópsias aspirativas percutâneas por agulha fina guiada por TC de pulmão, demonstrar a viabilidade diagnóstica do método na investigação de lesões pulmonares e determinar as complicações do procedimento, avaliando sua segurança. MÉTODOS: Análise retrospectiva com 89 pacientes com tipos diversos de lesões pulmonares que foram submetidos a 97 procedimentos em um período de cinco anos. Os pacientes foram divididos em grupos de acordo com a indicação para o procedimento: suspeita de neoplasia pulmonar primária (estádios IIIB e IV); suspeita de neoplasia pulmonar (estádios I, II e IIIA) e contraindicações clínicas para cirurgia; suspeita de metástase pulmonar oriunda de outros órgãos; e lesões pulmonares com aspecto radiológico benigno. O método foi padronizado com agulha fina de 25 gauge. Todos os procedimentos foram guiados por TC helicoidal. O diagnóstico final foi confirmado por biópsias cirúrgicas e acompanhamento clínico/oncológico. Para a análise das complicações, foi considerado o número total de procedimentos. RESULTADOS: A principal indicação do procedimento foi a suspeita de neoplasia pulmonar primária avançada. O método apresentou acurácia de 91,5 por cento para lesões malignas. A lesão foi confirmada como neoplásica em 73 por cento dos pacientes. A principal complicação foi o pneumotórax (27,8 por cento), com necessidade de drenagem tubular em 12,4 por cento do total de procedimentos. CONCLUSÕES: A principal indicação para biópsia por agulha fina guiada por TC foi a suspeita de doença neoplásica pulmonar primária sem possibilidade de tratamento cirúrgico. O procedimento tem alta viabilidade diagnóstica para doenças pulmonares de origem neoplásica. A mais prevalente complicação foi o pneumotórax, sem necessidade de drenagem tubular na maioria dos casos. Não ocorreram óbitos relacionados ao procedimento.

OBJECTIVE: To analyze the cytological findings of CT-guided percutaneous fine-needle aspiration biopsies of the lung, to demonstrate the diagnostic feasibility of the method in the investigation of pulmonary lesions, and to determine the complications of the procedure, evaluating its safety. METHODS: A retrospective analysis of 89 patients with various types of pulmonary lesions who underwent 97 procedures over a period of five years. The patients were divided into groups regarding the indication for the procedure: suspicion of primary lung cancer (stages IIIB or IV); suspicion of lung cancer (stages I, II, or IIIA) and clinical contraindications for surgery; suspicion of pulmonary metastasis from other organs; and pulmonary lesions with benign radiological aspect. All of the procedures were performed with 25-gauge needles and were guided by spiral CT. The final diagnosis was confirmed by surgical biopsy and clinical/oncological follow-up. For the analysis of complications, the total number of procedures was considered. RESULTS: The main indication for the procedure was suspicion of advanced-stage primary lung cancer. The accuracy of the method for malignant lesions was 91.5 percent. The lesion was confirmed as cancer in 73 percent of the patients. The major complication was pneumothorax (27.8 percent), which required chest tube drainage in 12.4 percent of the procedures. CONCLUSIONS: The principal indication for CT-guided fine-needle biopsy was suspicion of primary lung cancer in patients who were not surgical candidates. The procedure has high diagnostic feasibility for malignant pulmonary diseases. The most prevalent complication was pneumothorax. However, in most cases, chest tube drainage was unnecessary. No deaths were related to the procedure.

[Usefulness of chest CT in the diagnosis of pulmonary sequestration]. / A utilidade da TC de tórax no diagnóstico do sequestro pulmonar.

Pulmonary sequestration is a rare congenital anomaly, characterized by nonfunctional embryonic pulmonary tissue. Pulmonary sequestration accounts for 0.15-6.40% of all congenital pulmonary malformations. This anomaly, which is classified as intralobar or extralobar, involves the lung parenchyma and its vascularization. We report the case of a 56-year-old male presenting with hemoptysis. A chest X-ray showed an area of opacity behind the cardiac silhouette in the base of the left hemithorax. Chest CT scans with intravenous contrast revealed pulmonary sequestration. The patient underwent surgery, in which the anomalous tissue was successful resected. The postoperative evolution was favorable, and the patient was discharged to outpatient treatment.

A utilidade da TC de tórax no diagnóstico do sequestro pulmonar / Usefulness of chest CT in the diagnosis of pulmonary sequestration

O sequestro pulmonar é uma rara anomalia congênita, caracterizada por tecido pulmonar embrionário não funcionante, perfazendo 0,15-6,40 por cento de todas as malformações pulmonares congênitas. Essa anomalia envolve o parênquima e a vascularização pulmonar, sendo classificado como intralobar ou extralobar. Neste relato, descrevemos o caso de um paciente de 56 anos com hemoptise e imagem hipotransparente retrocardíaca em base de hemitórax esquerdo na radiografia de tórax. Após a realização de TC com contraste endovenoso, foi evidenciada a presença de sequestro pulmonar. O paciente foi submetido à cirurgia para a retirada do tecido anômalo, que foi realizada com sucesso. Apresentou boa evolução pós-operatória e recebeu alta com acompanhamento ambulatorial.

Pulmonary sequestration is a rare congenital anomaly, characterized by nonfunctional embryonic pulmonary tissue. Pulmonary sequestration accounts for 0.15-6.40 percent of all congenital pulmonary malformations. This anomaly, which is classified as intralobar or extralobar, involves the lung parenchyma and its vascularization. We report the case of a 56-year-old male presenting with hemoptysis. A chest X-ray showed an area of opacity behind the cardiac silhouette in the base of the left hemithorax. Chest CT scans with intravenous contrast revealed pulmonary sequestration. The patient underwent surgery, in which the anomalous tissue was successful resected. The postoperative evolution was favorable, and the patient was discharged to outpatient treatment.

Quantitative assessment of elastic fibers in chronic obstructive pulmonary disease.

OBJECTIVE: To quantify elastic fibers (EFs) and smooth muscle (SM) cells, as well as CD4+ and CD8+ T lymphocytes, in stable chronic obstructive pulmonary disease (COPD). METHODS: Surgical specimens were obtained from 15 COPD patients, 18 smokers without airflow limitation, and 14 nonsmokers. Histological and immunohistochemical methods were employed in order to quantify EFs, SM cells, CD4+ T cells, and CD8+ T cells. RESULTS: There was no significant difference in EF numbers among the three groups (p > 0.05). The number of EFs per unit area of lung tissue (mm(2)) and the percentage of EFs in the lung tissue were similar among the three groups. The numbers of SM cells were found to be higher in the COPD patients than in the smokers (p = 0.003) or in the nonsmokers (p = 0.009). There was a tendency toward an increase in CD8+ T-cell counts in the COPD patients. In specimens collected from the COPD patients, CD4+ T-cell counts were lower than in those collected from the smokers (p = 0.015) or from the nonsmokers (p = 0.003). There was a weak correlation between CD4+ T-cell count and the ratio of forced expiratory volume in one second to forced vital capacity (r(2) = 0.003). CONCLUSIONS: The EF counts were similar among the three groups. Hypertrophy/hyperplasia of airway wall SM cells was found in the COPD patients and in the smokers, indicating that airway remodeling occurs in smokers. The CD4/CD8 ratio was lower in the COPD patients.

Avaliação quantitativa das fibras elásticas na doença pulmonar obstrutiva crônica / Quantitative assessment of elastic fibers in chronic obstructive pulmonary disease

OBJETIVO: Quantificar fibras elásticas (FE), músculo liso (ML) e linfócitos T CD4+ e CD8+ na doença pulmonar obstrutiva crônica (DPOC) estável. MÉTODOS: Biópsias cirúrgicas foram obtidas de 15 pacientes com DPOC, 18 tabagistas sem limitação do fluxo aéreo e 14 não tabagistas. FE, ML e células T CD4+ e CD8+ foram quantificados através de métodos histológicos e imuno-histoquímicos. RESULTADOS: Não foi observada diferença estatisticamente significativa das FE nos três grupos (p > 0,05). Tanto a quantidade de FE por unidade de área pulmonar (mm²), quanto o percentual destas fibras por tecido pulmonar foram semelhantes nos três grupos. Foi encontrado aumento da quantidade de ML em pacientes com DPOC quando comparados a tabagistas (p = 0,003) e não tabagistas (p = 0,009). Houve tendência de aumento das células T CD8+ nos pacientes com DPOC. O total de células T CD4+ estava diminuído nos pacientes com DPOC quando comparados aos tabagistas (p = 0,015) e não tabagistas (p = 0,003). Observou-se fraca correlação entre estas células e a relação entre o volume expiratório forçado no primeiro segundo e a capacidade vital forçada (r² = 0,003). CONCLUSÕES: A quantidade de FE foi semelhante nos três grupos estudados. A hipertrofia/hiperplasia muscular da parede das vias aéreas foi encontrada tanto em pacientes com DPOC quanto em tabagistas, indicando que o remodelamento ocorra também nos tabagistas sem limitação do fluxo aéreo. Houve diminuição da relação CD4/CD8 em pacientes com DPOC.

OBJECTIVE: To quantify elastic fibers (EFs) and smooth muscle (SM) cells, as well as CD4+ and CD8+ T lymphocytes, in stable chronic obstructive pulmonary disease (COPD). METHODS: Surgical specimens were obtained from 15 COPD patients, 18 smokers without airflow limitation, and 14 nonsmokers. Histological and immunohistochemical methods were employed in order to quantify EFs, SM cells, CD4+ T cells, and CD8+ T cells. RESULTS: There was no significant difference in EF numbers among the three groups (p > 0.05). The number of EFs per unit area of lung tissue (mm²) and the percentage of EFs in the lung tissue were similar among the three groups. The numbers of SM cells were found to be higher in the COPD patients than in the smokers (p = 0.003) or in the nonsmokers (p = 0.009). There was a tendency toward an increase in CD8+ T-cell counts in the COPD patients. In specimens collected from the COPD patients, CD4+ T-cell counts were lower than in those collected from the smokers (p = 0.015) or from the nonsmokers (p = 0.003). There was a weak correlation between CD4+ T-cell count and the ratio of forced expiratory volume in one second to forced vital capacity (r² = 0.003). CONCLUSIONS: The EF counts were similar among the three groups. Hypertrophy/hyperplasia of airway wall SM cells was found in the COPD patients and in the smokers, indicating that airway remodeling occurs in smokers. The CD4/CD8 ratio was lower in the COPD patients.

Adenoma alveolar / Alveolar adenoma

O adenoma alveolar é uma neoplasia benigna rara dos pulmões, com poucos casos descritos na literatura. Freqüentemente, o paciente é assintomático e apresenta-se com um achado acidental em telerradiografias de tórax de um nódulo solitário e bem circunscrito. O diagnóstico definitivo é histológico e o tratamento consiste na ressecção cirúrgica do nódulo.

Alveolar adenoma is a rare benign neoplasm of the lungs, and very few cases have been described in the literature. Patients with alveolar adenoma are frequently asymptomatic and are diagnosed through the accidental discovery of a singular, well-delineated nodule on a routine chest X-ray. The definitive diagnosis is made histologically, and the treatment consists of surgical resection of the nodule.

Alveolar adenoma.

Alveolar adenoma is a rare benign neoplasm of the lungs, and very few cases have been described in the literature. Patients with alveolar adenoma are frequently asymptomatic and are diagnosed through the accidental discovery of a singular, well-delineated nodule on a routine chest X-ray. The definitive diagnosis is made histologically, and the treatment consists of surgical resection of the nodule.

Ressecção de hemangioma de pleura por cirurgia torácica vídeo-assistida (CTVA) / Ressection of pleural haemangioma by video-assisted thoracic surgery (VATS)

O presente caso refere-se a uma paciente de 79 anos que se apresentou com quadro de astenia, mialgia e coriza. Ao realizar uma telerradiografia de tórax foi evidenciada uma tumoração como achado incidental. Foi solicitada uma tomografia computadorizada que evidenciou lesão de provável localização pleural, sugerida pelo seu ângulo de implantação com a parede torácica. A paciente não apresentava sintomatologia ou fatores de risco relacionados a neoplasias pulmonares. Por tratar-se de lesão única, pequena e de localização pleural foi submetida à ressecção da tumoração, por cirurgia torácica vídeo-assistida. O resultado do exame histopatológico foi conclusivo de hemangioma capilar localizado na pleura. A paciente evoluiu bem e obteve alta no quarto dia pós-operatório.

Pleurodese / Pleurodesis

A pleurodese é um dos tratamentos mais utilizados para o derrame pleural sintomático recorrente, pois promove a obliteração da cavidade pleural. Não apenas o derrame pleural não responsivo ao tratamento clínico (derrame pleural neoplásico recidivante e os derrames crônicos não neoplásicos) teria indicação de pleurodese, mas também o pneumotórax de repetição. Verificamos que inúmeros trabalhos sobre pleurodese buscam a substância ideal para este propósito, levando-se em consideração não só a capacidade da substância de provocar aderências entre as pleuras, mas também aqueles com menos efeitos colaterais. Nesta revisão de literatura, procuramos enfocar as diversas maneiras de realização de pleurodese, bem como as principais substâncias utilizadas para este propósito.

Timectomia estendida por cirurgia torácica videoassistida e cervicotomia no tratamento da miastenia / Extended thymectomy through video assisted thoracic surgery and cervicotomy in the treatment of myasthenia

INTRODUÇAO: A relação entre a miastenia e o timo é evidente e o tratamento atual desta condição inclui a timectomia. No entanto, uma revisão de nossa experiência com a timectomia revelou a necessidade do uso de uma técnica mais radical. OBJETIVO: Analisar retrospectivamente pacientes portadores de miastenia gravis que foram submetidos a timectomia radical por videotoracoscopia, ressaltando vantagens do método, complicações, análise histopatológica e resultados em relação ao controle da doença. MATERIAL E MÉTODO: Vinte e um pacientes miastênicos (18 do sexo feminino e três do sexo masculino, com idade variando de 17 a 51 anos) foram submetidos a timectomia por videotoracoscopia bilateral associada a cervicotomia transversa com ressecção da glândula tímica, dos tecidos peritímicos e das gorduras pericárdicas direita e esquerda. Todos os tecidos implicados foram analisados pela anatomia patológica separadamente. Houve acompanhamento por período médio de 39,2 meses. RESULTADOS: Não houve mortalidade operatória. Ocorreram duas (9,5 por cento) lesões vasculares e um (4,8 por cento) paciente passou a apresentar disfonia leve permanente. Dezenove (90,4 por cento) pacientes estão com boa evolução, sem medicação ou com dose reduzida da mesma. A histopatologia demonstrou 10 hiperplasias do timo, seis involuções tímicas e cinco timos normais. A presença de tecido tímico ectópico foi detectada em seis (28,6 por cento) pacientes. CONCLUSAO: A timectomia radical por videotoracoscopia ofereceu bom controle da miastenia gravis. Fez-se ressecção de tecido tímico ectópico em alguns pacientes.

Modelo experimental de pleurodese induzida por sulfato de bário: estudo da mecânica respiratória e histoplatologia / Model experimental of pleurodesis induced by barium sulfate: respiratory mechanics and histopatology study

Este estudo tenciona desenvolver um modelo de pleurodese através da injeçäo intrapleural de sulfato de bário a 100 por cento e analisar a mecânica respiratória e a histologia pleural e do parêmquima pulmonar. Foram injetados na cavidade pleural direita soluçäo salina (2mL) (controle) ou sulfato de bário (suspensäo 2mL) (pleurodese) em ratos Wistar machos. Os animais foram sedados, anestesiados, traqueotomizados e as pressões elásticas, resistivas e viscoelástica/inomogêneas do sistema respiratório, pulmäo e parede torácica foram medidas pelo método de oclusäo no final da inspiraçäo. A pleura foi estudada determinando-se macroscopicamente a existência de pleurodose e microscopicamente a presença de inflamaçäo e fibrose, bem como a análise quantitativa do colágeno. Os efeitos no parênquima pulmonar também foram avaliados com relaçäo à presença de inflamaçäo e fibrose alveolar. As pressões elásticas, resistivas e viscoelásticas pulmonares aumentaram 48h após a injeçäo de sulfato de bário de forma significativa em relaçäo ao seu grupo controle. Em 30 dias, houve normalizaçäo desses parâmetro mecânicos. A pleurodese, juntamente com a fibrose pleural, além da quantidade de colágeno, foram significativamente maiores em relaçäo ao grupo controle, 48 horas e 30 dias. Quando se comparou os grupos submetidos à pleurodese, esses parâmetros näo se modificaram com o tempo, exceto pela presença de derrame pleural presente em 48 horas e por uma diminuiçäo de sulfato de bário, na cavidade pleural, em 30 dias. Näo foram observadas inflamaçäo ou fibrose alveolar em qualquer um dos grupos. Em conclusäo, o presente modelo demonstra que o sulfato de bário induz a pleurodese já numa fase precoce, sendo inócua ao pulmäo e com normalizaçäo das alterações da mecânica respiratória na fase tardia