Abstract Objective: To investigate the clinical and swallowing indicators related to a successful decannulation process during the hospital stay. Methods: A retrospective cohort clinical study. The study sample comprised a heterogeneous patient population who had submitted to a tracheostomy procedure in a tertiary hospital. Patients were divided into two groups (dec-annulated vs. non-decannulated) and compared not only in terms of demographic and clinical data but also the results of a swallowing assessment and intervention outcome. Results: Sixty-four patients were included in the present study: 25 (39%) who had been successfully decannulated, and 39 (61%) who could not be decannulated. Between-group comparisons indicated that both groups presented similar clinical and demographic characteristics. The groups also presented similar swallowing assessment results prior to intervention. However, significant differences were observed regarding the time to begin swallowing rehabilitation. The decannulated group was assessed nine days earlier than the non-decannulated group. Other significant differences included the removal of the alternate feeding method (72.0% of decannulated patients vs. 5.1% of non-decannulated patients) and the reintroduction of oral feeding (96.0% of decannulated patients vs. 41.0% of non-decannulated patients) and functional swallowing level at patient disclosure. The non-decannulated patient group presented higher death rates at disclosure. Conclusion: The results of the present study indicated that the following parameters were associated with a successful decannulation process: early swallowing assessment, swallowing rehabilitation, and improvement in the swallowing functional level during the hospital stay. The maintenance of low swallowing functional levels was found to be negatively associated with successful decannulation. HIGHLIGHTS Deccanulation indicators were investigated in patients who were submitted to a tracheostomy procedure. Early swallowing evaluation and rehabilitation were associated with a successful decannulation process. Low swallowing functional levels were negatively associated with the success of decannulation.

RESUMO Objetivo: O câncer de pulmão (CP) é uma das principais causas de morte no mundo. Um estadiamento mediastinal preciso é obrigatório para avaliação do prognóstico e seleção de pacientes para tratamento cirúrgico. EBUS-TBNA é um procedimento minimamente invasivo que permite a amostragem de linfonodos mediastinais. Alguns estudos sugerem que a EBUS-TBNA é preferível que a mediastinoscopia cirúrgica no estadiamento mediastinal do CP. O objetivo desta revisão sistemática e meta-análise foi comparar a eficácia da EBUS-TBNA e da mediastinoscopia no estadiamento linfonodal mediastinal do câncer de pulmão de células não pequenas (CPCNP) potencialmente operável. Métodos: Foram pesquisados diversos bancos de dados. Estudos comparando a precisão da EBUS-TBNA e da mediastinoscopia no estadiamento linfonodal mediastinal em pacientes com CPCNP foram incluídos. Na meta-análise, foram calculadas sensibilidade e especificidade, bem como razões de verossimilhança positiva e negativa. A diferença de risco de complicações relatadas para cada procedimento também foi analisada. Resultados: A pesquisa identificou 4.201 artigos, dos quais 5 foram selecionados para a meta-análise (total combinado de 532 pacientes). Não houve diferenças estatisticamente significativas entre EBUS-TBNA e mediastinoscopia: sensibilidade (81% vs. 75%), especificidade (100% para ambas), razão de verossimilhança positiva (101,03 vs. 95,70) e razão de verossimilhança negativa (0,21 vs. 0,23). A área sob a curva summary ROC para EBUS-TBNA e para mediastinoscopia foi de 0,9881 e 0,9895, respectivamente. Embora o número de complicações tenha sido maior para mediastinoscopia, não foi encontrada diferença significativa (diferença de risco: −0,03; IC95%: −0,07 to 0,01; I2 = 76%). Conclusões: EBUS-TBNA e mediastinoscopia apresentaram resultados semelhantes no estadiamento mediastinal do CPCNP. EBUS-TBNA pode ser o procedimento de primeira escolha no estadiamento linfonodal em pacientes com CPCNP.

ABSTRACT Objective: Lung cancer (LC) is one of the leading causes of death worldwide. Accurate mediastinal staging is mandatory in order to assess prognosis and to select patients for surgical treatment. EBUS-TBNA is a minimally invasive procedure that allows sampling of mediastinal lymph nodes (LNs). Some studies have suggested that EBUS-TBNA is preferable to surgical mediastinoscopy for mediastinal staging of LC. The objective of this systematic review and meta-analysis was to compare EBUS-TBNA and mediastinoscopy in terms of their effectiveness for mediastinal LN staging in potentially operable non-small cell lung cancer (NSCLC). Methods: This was a systematic review and meta-analysis, in which we searched various databases. We included studies comparing the accuracy of EBUS-TBNA with that of mediastinoscopy for mediastinal LN staging in patients with NSCLC. In the meta-analysis, we calculated sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios. We also analyzed the risk difference for the reported complications associated with each procedure. Results: The search identified 4,201 articles, 5 of which (with a combined total of 532 patients) were selected for inclusion in the meta-analysis. There were no statistically significant differences between EBUS-TBNA and mediastinoscopy in terms of the sensitivity (81% vs. 75%), specificity (100% for both), positive likelihood ratio (101.03 vs. 95.70), or negative likelihood ratio (0.21 vs. 0.23). The area under the summary ROC curve was 0.9881 and 0.9895 for EBUS-TBNA and mediastinoscopy, respectively. Although the number of complications was higher for mediastinoscopy, the difference was not significant (risk difference: −0.03; 95% CI: −0.07 to 0.01; I2 = 76%). Conclusions: EBUS-TBNA and mediastinoscopy produced similar results for mediastinal staging of NSCLC. EBUS-TBNA can be the procedure of first choice for LN staging in patients with NSCLC.

RESUMO Objetivo: Analisar as complicações relacionadas à broncoscopia flexível (BF) e a seus procedimentos de coleta em diferentes doenças pulmonares e de vias aéreas em pacientes ambulatoriais e internados em um hospital universitário. Métodos: Foram analisadas retrospectivamente complicações precoces que ocorreram durante e após BF (em até 2 h) registrados no banco de dados do Serviço de Endoscopia Respiratória de um complexo hospitalar localizado na cidade de São Paulo (SP) entre janeiro de 2012 e dezembro de 2013. Resultados: Foram analisadas 3.473 BF. Complicações ocorreram em 185 procedimentos (5,3%): sangramento moderado a acentuado, em 2,2%; pneumotórax, em 0,7%; broncoespasmo grave, em 0,8%; complicações gerais (hipoxemia, agitação psicomotora, arritmias, vômitos e hipotensão), em 1,6%; e parada cardiorrespiratória, em 0,03%. Não houve óbitos relacionados aos procedimentos. Especificamente, nos 1.728 pacientes submetidos a biópsias, escovado brônquico e punção aspirativa por agulha fina, houve sangramentos em 75 (4,3%.) Entre os 1.191 pacientes que realizaram biópsia transbrônquica, pneumotórax (com necessidade de drenagem torácica) ocorreu em 24 (2,0%). Conclusões: Neste grupo de pacientes, a BF se mostrou um método seguro com baixo índice de complicações. A formação adequada e continuada dos médicos especialistas e da equipe de enfermagem, bem como a elaboração de protocolos de atendimento padronizados, são importantes nesse sentido.

ABSTRACT Objective: To analyze the complications related to flexible bronchoscopy (FB) and its collection procedures in outpatients and inpatients with various lung and airway diseases treated at a university hospital. Methods: This was a retrospective analysis of complications occurring during or within 2 h after FB performed between January of 2012 and December of 2013, as recorded in the database of the respiratory endoscopy department of a hospital complex in the city of São Paulo, Brazil. Results: We analyzed 3,473 FBs. Complications occurred in 185 procedures (5.3%): moderate to severe bleeding, in 2.2%; pneumothorax, in 0.7%; severe bronchospasm, in 0.8%; general complications (hypoxemia, psychomotor agitation, arrhythmias, vomiting, or hypotension), in 1.6%; and cardiopulmonary arrest, in 0.03%. There were no deaths related to the procedures. Specifically, among the 1,728 patients undergoing biopsy, bronchial brushing, or fine-needle aspiration biopsy, bleeding occurred in 75 (4.3%). Among the 1,191 patients undergoing transbronchial biopsy, severe pneumothorax (requiring chest tube drainage) occurred in 24 (2.0%). Conclusions: In our patient sample, FB proved to be a safe method with a low rate of complications. Appropriate continuing training of specialist doctors and nursing staff, as well as the development of standardized care protocols, are important for maintaining those standards.

RESUMO Objetivo: A broncoscopia convencional possui baixo rendimento diagnóstico para lesões pulmonares periféricas. A ecobroncoscopia radial (EBUS radial) emprega um transdutor ultrassonográfico rotatório na extremidade de uma sonda que é inserida no canal de trabalho do broncoscópio. O EBUS radial facilita a localização de nódulos pulmonares periféricos, aumentando assim o rendimento diagnóstico. O objetivo deste estudo foi apresentar nossa experiência inicial com o uso de EBUS radial para o diagnóstico de lesões pulmonares periféricas em um hospital terciário. Métodos: Foi realizada uma análise retrospectiva de 54 pacientes submetidos à broncoscopia guiada por EBUS radial para a investigação de nódulos ou massas pulmonares entre fevereiro de 2012 e setembro de 2013. O EBUS radial foi realizado com uma sonda flexível de 20 MHz, que foi inserida no canal de trabalho do broncoscópio até chegar à lesão-alvo. A fluoroscopia foi usada para localizar a lesão e realizar procedimentos de coleta (escovado brônquico, aspiração transbrônquica com agulha e biópsia transbrônquica). Resultados: O EBUS radial identificou 39 nódulos (média de diâmetro: 1,9 ± 0,7 cm) e 19 massas (média de diâmetro: 4,1 ± 0,9 cm). A sensibilidade global do EBUS radial foi de 66,7% (79,5% para as lesões visíveis pelo método e 25% para as lesões não visíveis pelo método). Nas lesões visíveis pelo método, a sensibilidade foi de 91,7% para massas e de 74,1% para nódulos. As complicações foram pneumotórax (3,7%) e sangramento brônquico controlado broncoscopicamente (9,3%). Conclusões: O EBUS radial apresenta bom perfil de segurança, baixo índice de complicações e alta sensibilidade para o diagnóstico de lesões pulmonares periféricas.

ABSTRACT Objective: Conventional bronchoscopy has a low diagnostic yield for peripheral pulmonary lesions. Radial-probe EBUS employs a rotating ultrasound transducer at the end of a probe that is passed through the working channel of the bronchoscope. Radial-probe EBUS facilitates the localization of peripheral pulmonary nodules, thus increasing the diagnostic yield. The objective of this study was to present our initial experience using radial-probe EBUS in the diagnosis of peripheral pulmonary lesions at a tertiary hospital. Methods: We conducted a retrospective analysis of 54 patients who underwent radial-probe EBUS-guided bronchoscopy for the investigation of pulmonary nodules or masses between February of 2012 and September of 2013. Radial-probe EBUS was performed with a flexible 20-MHz probe, which was passed through the working channel of the bronchoscope and advanced through the bronchus to the target lesion. For localization of the lesion and for collection procedures (bronchial brushing, transbronchial needle aspiration, and transbronchial biopsy), we used fluoroscopy. Results: Radial-probe EBUS identified 39 nodules (mean diameter, 1.9 ± 0.7 cm) and 19 masses (mean diameter, 4.1 ± 0.9 cm). The overall sensitivity of the method was 66.7% (79.5% and 25.0%, respectively, for lesions that were visible and not visible by radial-probe EBUS). Among the lesions that were visible by radial-probe EBUS, the sensitivity was 91.7% for masses and 74.1% for nodules. The complications were pneumothorax (in 3.7%) and bronchial bleeding, which was controlled bronchoscopically (in 9.3%). Conclusions: Radial-probe EBUS shows a good safety profile, a low complication rate, and high sensitivity for the diagnosis of peripheral pulmonary lesions.

Objetivo: A endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA, punção aspirativa por agulha guiada por ultrassom endobrônquico) é um método seguro e preciso para a coleta de amostras de linfonodos mediastinais e hilares. O presente estudo teve por objetivo avaliar os resultados iniciais com EBUS-TBNA para o estadiamento linfonodal de câncer de pulmão em 3 hospitais acadêmicos no Brasil. Métodos: Análise retrospectiva de pacientes com neoplasia de pulmão diagnosticada e submetidos a EBUS-TBNA para estadiamento linfonodal mediastinal. Todos os procedimentos foram realizados sob anestesia geral. Utilizou-se um ecobroncoscópio, uma processadora de ultrassom e agulhas 22 G descartáveis e compatíveis com o ecobroncoscópio. Resultados: Entre janeiro de 2011 e janeiro de 2014, 149 pacientes foram submetidos ao estadiamento linfonodal com EBUS-TBNA. A média de idade foi 66 ± 12 anos, sendo 58% do sexo masculino. Um total de 407 linfonodos foram puncionados via EBUS-TBNA. Os tipos mais comuns de neoplasia brônquica foram adenocarcinoma (em 67%) e carcinoma escamoso (em 24%). Para o estadiamento da neoplasia, o EBUS-TBNA apresentou sensibilidade de 96%, especificidade de 100% e valor preditivo negativo de 85%. Conclusões: A EBUS-TBNA mostrou-se um método seguro e acurado no estadiamento linfonodal em pacientes com câncer de pulmão.

Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive, safe and accurate method for collecting samples from mediastinal and hilar lymph nodes. This study focused on the initial results obtained with EBUS-TBNA for lung cancer and lymph node staging at three teaching hospitals in Brazil. Methods: This was a retrospective analysis of patients diagnosed with lung cancer and submitted to EBUS-TBNA for mediastinal lymph node staging. The EBUS-TBNA procedures, which involved the use of an EBUS scope, an ultrasound processor, and a compatible, disposable 22 G needle, were performed while the patients were under general anesthesia. Results: Between January of 2011 and January of 2014, 149 patients underwent EBUS-TBNA for lymph node staging. The mean age was 66 ± 12 years, and 58% were male. A total of 407 lymph nodes were sampled by EBUS-TBNA. The most common types of lung neoplasm were adenocarcinoma (in 67%) and squamous cell carcinoma (in 24%). For lung cancer staging, EBUS-TBNA was found to have a sensitivity of 96%, a specificity of 100%, and a negative predictive value of 85%. Conclusions: We found EBUS-TBNA to be a safe and accurate method for lymph node staging in lung cancer patients.

OBJECTIVES:Despite the recent success regarding the transplantation of tissue-engineered airways, the mechanical properties of these grafts are not well understood. Mechanical assessment of a tissue-engineered airway graft before implantation may be used in the future as a predictor of function. The aim of this preliminary work was to develop a noninvasive image-processing environment for the assessment of airway mechanics.METHOD:Decellularized, recellularized and normal tracheas (groups DECEL, RECEL, and CONTROL, respectively) immersed in Krebs-Henseleit solution were ventilated by a small-animal ventilator connected to a Fleisch pneumotachograph and two pressure transducers (differential and gauge). A camera connected to a stereomicroscope captured images of the pulsation of the trachea before instillation of saline solution and after instillation of Krebs-Henseleit solution, followed by instillation with Krebs-Henseleit with methacholine 0.1 M (protocols A, K and KMCh, respectively). The data were post-processed with computer software and statistical comparisons between groups and protocols were performed.RESULTS:There were statistically significant variations in the image measurements of the medial region of the trachea between the groups (two-way analysis of variance [ANOVA], p<0.01) and of the proximal region between the groups and protocols (two-way ANOVA, p<0.01).CONCLUSIONS:The technique developed in this study is an innovative method for performing a mechanical assessment of engineered tracheal grafts that will enable evaluation of the viscoelastic properties of neo-tracheas prior to transplantation.

Objetivo: Determinar os efeitos da administração aguda e crônica de metilprednisolona no estresse oxidativo, por meio da quantificação da peroxidação lipídica (POL) e do potencial antioxidante reativo total (PART), em pulmões de ratos. Métodos: Quarenta ratos Wistar foram divididos em quatro grupos: tratamento agudo, com ratos recebendo uma dose única de metilprednisolona (50 mg/kg i.p.); controle agudo, com ratos recebendo injeção unida de salina; tratamento crônico, com ratos recebendo metilprednisolona v.o. na água do bebedouro (6 mg/kg por dia durante 30 dias; e controle crônico, com ratos recebendo água de bebedouro normal). Resultados: Os níveis de PART foram significativamente maiores no grupo tratamento agudo que no grupo controle agudo, sugerindo uma melhora do sistema de defesa pulmonar. Os níveis de POL foram significativamente maiores no grupo tratamento crônico que no grupo controle crônico, indicando dano oxidativo no tecido pulmonar. Conclusões: Nossos resultados sugerem que o uso agudo de corticoides foi benéfico aos tecidos pulmonares, enquanto seu uso crônico não o foi. O uso crônico de metilprednisolona parece aumentar os níveis pulmonares da POL.

Objective: To determine the effects of acute and chronic administration of methylprednisolone on oxidative stress, as quantified by measuring lipid peroxidation (LPO) and total reactive antioxidant potential (TRAP), in rat lungs. Methods: Forty Wistar rats were divided into four groups: acute treatment, comprising rats receiving a single injection of methylprednisolone (50 mg/kg i.p.); acute control, comprising rats i.p. injected with saline; chronic treatment, comprising rats receiving methylprednisolone in drinking water (6 mg/kg per day for 30 days); and chronic control, comprising rats receiving normal drinking water. Results: The levels of TRAP were significantly higher in the acute treatment group rats than in the acute control rats, suggesting an improvement in the pulmonary defenses of the former. The levels of lung LPO were significantly higher in the chronic treatment group rats than in the chronic control rats, indicating oxidative damage in the lung tissue of the former. Conclusions: Our results suggest that the acute use of corticosteroids is beneficial to lung tissue, whereas their chronic use is not. The chronic use of methylprednisolone appears to increase lung LPO levels.

OBJETIVO: Avaliar os efeitos da administração sistêmica precoce e tardia de metilprednisolona nos pulmões em um modelo de morte encefálica em ratos. MÉTODOS: Vinte e quatro ratos Wistar machos foram anestesiados e randomizados em quatro grupos (n = 6 por grupo): sham, somente morte encefálica (ME), metilprednisolona i.v. (30 mg/kg) administrada 5 min após a morte encefálica (MP5) e 60 min após a morte encefálica (MP60). Os grupos ME, MP5 e MP60 foram submetidos à morte encefálica por insuflação de um balão no espaço extradural. Todos os animais foram observados e ventilados durante 120 min. Foram determinadas variáveis hemodinâmicas e gasométricas, relação peso úmido/seco, escore histológico, thiobarbituric acid reactive substances (TBARS, substâncias reativas ao ácido tiobarbitúrico), atividade de superóxido dismutase (SOD) e de catalase, assim como contagem diferencial de células brancas, proteína total e nível de desidrogenase lática no LBA. A atividade da mieloperoxidase, peroxidação lipídica e níveis de TNF-α foram avaliados no tecido pulmonar. RESULTADOS: Não foram observadas diferenças significativas nas variáveis hemodinâmicas e gasométricas, relação peso úmido/seco, análises do LBA, escore histológico, SOD, mieloperoxidase e catalase entre os grupos. Os níveis de TBARS foram significativamente maiores nos grupos MP5 e MP60 do que nos grupos sham e ME (p < 0,001). Os níveis de TNF-α foram significativamente menores nos grupos MP5 e MP60 do que no grupo ME (p < 0,001). CONCLUSÕES: Neste modelo de morte cerebral, a administração precoce e tardia de metilprednisolona apresentou efeitos semelhantes sobre a inflamação e a peroxidação lipídica no tecido pulmonar.

OBJECTIVE: To evaluate the effects that early and late systemic administration of methylprednisolone have on lungs in a rat model of brain death. METHODS: Twenty-four male Wistar rats were anesthetized and randomly divided into four groups (n = 6 per group): sham-operated (sham); brain death only (BD); brain death plus methylprednisolone (30 mg/kg i.v.) after 5 min (MP5); and brain death plus methylprednisolone (30 mg/kg i.v.) after 60 min (MP60). In the BD, MP5, and MP60 group rats, we induced brain death by inflating a balloon catheter in the extradural space. All of the animals were observed and ventilated for 120 min. We determined hemodynamic and arterial blood gas variables; wet/dry weight ratio; histological score; levels of thiobarbituric acid reactive substances (TBARS); superoxide dismutase (SOD) activity; and catalase activity. In BAL fluid, we determined differential white cell counts, total protein, and lactate dehydrogenase levels. Myeloperoxidase activity, lipid peroxidation, and TNF-α levels were assessed in lung tissue. RESULTS: No significant differences were found among the groups in terms of hemodynamics, arterial blood gases, wet/dry weight ratio, BAL fluid analysis, or histological score-nor in terms of SOD, myeloperoxidase, and catalase activity. The levels of TBARS were significantly higher in the MP5 and MP60 groups than in the sham and BD groups (p < 0.001). The levels of TNF-α were significantly lower in the MP5 and MP60 groups than in the BD group (p < 0.001). CONCLUSIONS: In this model of brain death, the early and late administration of methylprednisolone had similar effects on inflammatory activity and lipid peroxidation in lung tissue.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA, punção aspirativa por agulha guiada por ultrassom endobrônquico) tem desempenhado um papel fundamental no diagnóstico de lesões mediastinais, paratraqueais e peribrônquicas, assim como no estadiamento linfonodal da neoplasia pulmonar. Por se tratar de exame endoscópico minimamente invasivo cujo rendimento diagnóstico tem se mostrado comparável aos métodos cirúrgicos estabelecidos, o procedimento de EBUS-TBNA ganhou espaço rapidamente e já se encontra integrado à rotina de investigação em serviços de referência. Para a realização de EBUS-TBNA, é importante o planejamento prévio ao procedimento, que deve incluir uma análise minuciosa dos exames radiológicos e cuidado especial com a coleta e preparo do material, além do domínio da técnica e conhecimento de eventuais complicações inerentes ao procedimento. As principais indicações para a realização de EBUS-TBNA são o estadiamento linfonodal da neoplasia pulmonar e a investigação diagnóstica de massas e linfonodomegalias mediastinais ou hilares. Recentemente, iniciou-se a identificação de biomarcadores tumorais em amostras neoplásicas; essa análise molecular no material coletado durante o procedimento de EBUS-TBNA provou ser totalmente possível. Até o momento, o procedimento de EBUS-TBNA não consta nas tabelas de procedimentos médicos da Associação Médica Brasileira. O procedimento de EBUS-TBNA tem se mostrado seguro e eficaz no estadiamento e reestadiamento de neoplasia de pulmão e no esclarecimento diagnóstico de lesões ou linfonodomegalias mediastinais, paratraqueais e peribrônquicas.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has played a key role in the diagnosis of mediastinal, paratracheal, and peribronchial lesions, as well as in lymph node staging for lung cancer. Despite its minimally invasive character, EBUS-TBNA has demonstrated a diagnostic yield comparable with that of established surgical methods. It has therefore gained credibility and has become a routine procedure at various referral centers. A successful EBUS-TBNA procedure requires careful planning, which includes a thorough review of the radiological imaging and special care during specimen collection and preparation, as well as technical expertise, experience with the procedure itself, and knowledge of the potential complications inherent to the procedure. The most common indications for EBUS-TBNA include lymph node staging for lung cancer and the diagnostic investigation of mediastinal/hilar masses and lymph node enlargement. Recently, tumor biomarkers in malignant samples collected during the EBUS-TBNA procedure have begun to be identified, and this molecular analysis has proven to be absolutely feasible. The EBUS-TBNA procedure has yet to be included on the Brazilian Medical Association list of medical procedures approved for reimbursement. The EBUS-TBNA procedure has shown to be a safe and accurate tool for lung cancer staging/restaging, as well as for the diagnosis of mediastinal, paratracheal, and peribronchial lesions/lymph node enlargement

OBJECTIVE: This study evaluated the performance of lungs that were preserved with different solutions (Celsior, Perfadex or saline) in an ex vivo rat lung perfusion system. METHODS: Sixty Wistar rats were anesthetized, anticoagulated and randomized into three groups (n = 20). The rats were subjected to antegrade perfusion via the pulmonary artery with Perfadex, Celsior, or saline, followed by 6 or 12 hours of ischemia (4ºC, n = 10 in each group). Respiratory mechanics, gas exchange and hemodynamics were measured at 10-minute intervals during the reperfusion of heart-lung blocks in an ex vivo system (IL2-Isolated Perfused Rat or Guinea Pig Lung System, Harvard Apparatus, Holliston, Massachusetts, USA; Hugo Sachs Elektronik, Germany) for 60 minutes. The lungs were prepared for histopathology and evaluated for edema following reperfusion. Group comparisons were performed using ANOVA and the Kruskal-Wallis test with a 5% level of significance. RESULTS: Gas exchange was not significantly different between lungs perfused with either Perfadex or Celsior at the same ischemic times, but it was very low in lungs that were preserved with saline. Airway resistance was greater in the lungs that were preserved for 12 hours. Celsior lungs that were preserved for 6 and 12 hours exhibited lower airway resistance (p = 0.01) compared to Perfadex lungs. Pulmonary artery pressure was not different between the groups, and no significant differences in histopathology and apoptosis were observed between the groups. CONCLUSIONS: Lungs that were preserved with Celsior or Perfadex exhibited similar gas exchange and histopathological findings. Airway resistance was slightly lower in the Celsior-preserved lungs compared with the Perfadex-preserved lungs.

OBJETIVO: Comparar os achados histopatológicos e de apoptose em pulmões de ratos preservados em soluções low-potassium dextran (LPD, baixo potássio dextrana), histidine-tryptophan-ketoglutarate (HTK, histidina-triptofano-cetoglutarato) ou salina normal (SN) em 6 h e 12 h de isquemia pela utilização de um modelo experimental de perfusão pulmonar ex vivo. MÉTODOS: Sessenta ratos Wistar foram anestesiados, randomizados e submetidos à perfusão anterógrada pela artéria pulmonar com uma das soluções preservadoras. Após a extração, os blocos cardiopulmonares foram preservados por 6 ou 12 h a 4ºC, sendo então reperfundidos com sangue homólogo em um sistema de perfusão ex vivo durante 60 min. Ao final da reperfusão, fragmentos do lobo médio foram extraídos e processados para histopatologia, sendo avaliados os seguintes parâmetros: congestão, edema alveolar, hemorragia alveolar, hemorragia, infiltrado inflamatório e infiltrado intersticial. O grau de apoptose foi avaliado pelo método TdT-mediated dUTP nick end labeling. RESULTADOS: A histopatologia demonstrou que todos os pulmões preservados com SN apresentaram edema alveolar após 12 h de isquemia. Não houve diferenças em relação ao grau de apoptose nos grupos estudados. CONCLUSÕES: No presente estudo, os achados histopatológicos e de apoptose foram semelhantes com o uso das soluções LPD e HTK, enquanto a presença de edema foi significativamente maior com o uso de SN.

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 4ºC 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.

OBJETIVO: Apresentar um modelo experimental de administração de prostaglandina I2 (PGI2) por via inalatória vs. parenteral e avaliar o desempenho funcional dos pulmões em um sistema de perfusão pulmonar ex vivo. MÉTODOS: Quarenta ratos Wistar foram anestesiados, ventilados, submetidos a laparotomia com ressecção do esterno e anticoagulados. O tronco da artéria pulmonar foi canulado. Todos os animais foram submetidos a ventilação mecânica. Os animais foram randomizados em quatro grupos (10 ratos/grupo): salina nebulizada (SN); salina parenteral (SP); PGI2 nebulizada (PGI2N); e PGI2 parenteral (PGI2P). A dose de PGI2 nos grupos PGI2N e PGI2P foi de 20 e 10 µg/kg, respectivamente. Os blocos cardiopulmonares foram submetidos in situ a perfusão anterógrada com solução de baixo potássio e dextrana a 4ºC via artéria pulmonar, extraídos em bloco e armazenados a 4ºC por 6 h. Os blocos foram ventilados e perfundidos em um sistema ex vivo por 50 min, sendo obtidas medidas de mecânica ventilatória, hemodinâmica e trocas gasosas. RESULTADOS: Houve redução da pressão arterial pulmonar média após a nebulização em todos os grupos (p < 0,001), sem diferença entre os grupos. Na perfusão ex vivo, a mecânica ventilatória não diferiu entre os grupos. Houve redução da capacidade relativa de oxigenação ao longo da perfusão nos grupos SN e SP (p = 0,04), e houve aumento significativo da pressão arterial pulmonar no grupo SN. CONCLUSÕES: O modelo experimental de administração de PGI2 na extração pulmonar é exequível e confiável. Na reperfusão, os resultados de hemodinâmica e de trocas gasosas demonstraram tendência a um melhor desempenho com o uso de PGI2 do que com solução salina.

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 4ºC 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.