INTRODUÇÃO: Técnicas de expansão pulmonar são empregadas rotineiramente na recuperação da função pulmonar no pós-operatório de cirurgia cardíaca valvar. Nossa hipótese é que as técnicas de exercícios respiratórios e incentivador inspiratório apresentam efeitos de não inferioridade na função pulmonar quando aplicadas em pacientes avaliados por um escore de risco, que apresentam características de disfunção pulmonar pós-operatória e foram classificados em nível 1 de assistência fisioterapêutica. OBJETIVOS: a) comparar a função pulmonar de pacientes com disfunção pulmonar pós-operatória, submetidos às técnicas de exercícios respiratórios e de incentivador inspiratório no pós-operatório de cirurgia valvar mitral; b) estudar a influência do tipo de lesão valvar mitral, estenose e insuficiência, na evolução da função pulmonar c) comparar a evolução da função pulmonar entre pacientes com hipertensão arterial pulmonar grave e não grave. MÉTODOS: Dados foram coletados no préoperatório, no dia do retorno do paciente à Enfermaria (pós-operatório) e 5 dias após a aplicação das técnicas de expansão pulmonar. Os pacientes foram randomizados para os grupos EXE (exercícios respiratórios) e IS (incentivador inspiratório) realizando três séries de exercícios com 10 repetições, seguidas de tosse, exercícios de mobilização e deambulação. A função pulmonar foi avaliada pela espirometria, oxigenação, pressões musculares respiratórias máximas e presença de colapso pulmonar utilizando radiografias de tórax. Análise estatística utilizou ANOVA para medidas repetidas, teste qui-quadrado ou de Fisher, teste t-Student para nível de significância p < 0,05. RESULTADOS: De 153 pacientes 116 foram incluídos e classificados como nível 1 da assistência fisioterapêutica com 59 pacientes (51%) no grupo de EXE e 57 (49%) no grupo IS. Não houve diferenças estatisticamente significantes entre os grupos, exceto para o movimento toracoabdominal que no grupo EXE apresentou um maior número de casos com recuperação mais precoce. A função pulmonar reduziu significantemente no pós-operatório, com recuperação parcial no 5ºdia (p < 0,05). Frequências cardíaca e respiratória mantiveram-se elevadas (p < 0,05). As taxas de colapso pulmonar antes e após o estudo foram de 61% e 43% no grupo EXE e de 51% e 35% no grupo de IS. Não houve diferenças estatisticamente significantes quando se comparou os pacientes com estenose e insuficiência mitral. Pacientes com PAP >= 50 mmHg (n=55) apresentaram padrão ventilatório restritivo leve e menor oxigenação no préoperatório. CONCLUSÕES: A evolução da função pulmonar dos grupos EXE e IS demonstra não inferioridade entre as técnicas no pós-operatório de cirurgia valvar mitral com disfunção pulmonar, classificados por um sistema de avaliação fisioterapêutica. A recuperação da função pulmonar não apresentou diferenças entre estenose e insuficiência mitral. A presença de hipertensão pulmonar grave não influenciou a evolução da função pulmonar dos pacientes em pós-operatório de cirurgia valvar mitral / INTRODUCTION: Pulmonary expansion techniques are routinely used in the recovery of pulmonary function in the postoperative period of heart valve surgery. Our hypothesis is that the techniques of breathing exercises and incentive spirometry present effects of non-inferiority in pulmonary function when applied in patients evaluated by a risk score, which present postoperative pulmonary dysfunction features and were classified as level 1 of physiotherapeutic assistance. OBJECTIVES: a) to compare the pulmonary function of patients with postoperative pulmonary dysfunction, submitted to the techniques of breathing exercises and incentive spirometry in the postoperative mitral valve surgery; b) to study the influence of the type of mitral valve disease, stenosis and regurgitation in the pulmonary function evolution; c) to compare the pulmonary function evolution between patients with severe and non-severe pulmonary arterial hypertension. METHODS: The data were collected in the preoperative, on the return to the patient\'s ward (postoperative) and 5 days after intervention of the techniques of lung expansion. The patients were randomized to the EXE group (breathing exercises) and IS group (incentive spirometry) performed three sets of exercises with 10 repetitions, followed by cough, mobilization exercises and ambulation. Pulmonary function was assessed by spirometry, oxygenation, maximal respiratory muscle pressures and pulmonary collapse using chest X-rays. The statistical analysis ANOVA for repeated measures, chi-square test or Fisher, Student\'s t-test for significance level of p < 0.05. RESULTS: Of 153 patients 116 were included and classified as level 1 physiotherapeutic assistance with 59 patients (51%) in the EXE group and 57 (49%) in the IS group. There were no statistically significant differences between groups, except for the thoracoabdominal motion in the EXE group had a greater number of cases with earlier recovery. Lung function decreased significantly in the postoperative period, with partial recovery at 5th day of intervention (p < 0.05). Heart and respiratory rate remained high (p < 0.05). The lung collapse rates before and after the study were 61% and 43% in the EXE group and 51% and 35% in IS group. There were no statistically significant differences when we compared the patients with stenosis and mitral regurgitation. PAP >= 50mmHg patients (n= 55) had mild restrictive ventilatory pattern and reduced oxygenation in the pre-operative. CONCLUSIONS: The evolution of pulmonary function of EXE and IS groups with pulmonary dysfunction, classified by physiotherapeutic assessment system showed non-inferiority between techniques in the mitral valve surgery postoperative. The recovery of pulmonary function was not different between mitral stenosis and regurgitation. The presence of severe pulmonary hypertension no affects the evolution of pulmonary function in patients in the postoperative mitral valve surgery

<p>Deep breathing exercises are widely used in the postoperative care to prevent or reduce pulmonary complications, but no scientific evidence for the efficacy has been found after coronary artery bypass grafting (CABG) surgery. </p><p>The aim of the thesis was to describe postoperative pulmonary function and to evaluate the efficacy of deep breathing exercises performed with or without a blow bottle device for positive expiratory pressure (PEP) 10 cmH₂O or an inspiratory resistance-positive expiratory pressure (IR-PEP) mask with an inspiratory pressure of -5 cmH₂O and an expiratory pressure of +10 to +15 cmH₂O. </p><p>Patients undergoing CABG were instructed to perform 30 slow deep breaths hourly during daytime for the first four postoperative days. Patient management was similar in the groups, except for the different breathing techniques. </p><p>Measurements were performed preoperatively, on the fourth postoperative day and four months after surgery. The immediate effect of the deep breathing exercises was examined on the second postoperative day. Pulmonary function was assessed by spirometry, diffusion capacity for carbon monoxide and arterial blood gases. Atelectasis was determined by chest roentgenograms or spiral computed tomography (CT). </p><p>Lung volumes were markedly reduced on the fourth postoperative day. Four months after surgery the pulmonary function was still significantly reduced. On the second and fourth postoperative day all patients had atelectasis visible on CT. A single session of deep breathing exercises performed with or without a mechanical device caused a significant reduction in atelectasis and an improvement in oxygenation. No major differences between deep breathing performed with or without a blow bottle or IR-PEP-device were found, except for a lesser decrease in total lung capacity in the blow bottle group on the fourth postoperative day. Patients who performed deep breathing exercises after CABG had significantly smaller atelectasis and better pulmonary function on the fourth postoperative day compared to a control group who performed no exercises.</p>

Deep breathing exercises are widely used in the postoperative care to prevent or reduce pulmonary complications, but no scientific evidence for the efficacy has been found after coronary artery bypass grafting (CABG) surgery. The aim of the thesis was to describe postoperative pulmonary function and to evaluate the efficacy of deep breathing exercises performed with or without a blow bottle device for positive expiratory pressure (PEP) 10 cmH2O or an inspiratory resistance-positive expiratory pressure (IR-PEP) mask with an inspiratory pressure of -5 cmH2O and an expiratory pressure of +10 to +15 cmH2O. Patients undergoing CABG were instructed to perform 30 slow deep breaths hourly during daytime for the first four postoperative days. Patient management was similar in the groups, except for the different breathing techniques. Measurements were performed preoperatively, on the fourth postoperative day and four months after surgery. The immediate effect of the deep breathing exercises was examined on the second postoperative day. Pulmonary function was assessed by spirometry, diffusion capacity for carbon monoxide and arterial blood gases. Atelectasis was determined by chest roentgenograms or spiral computed tomography (CT). Lung volumes were markedly reduced on the fourth postoperative day. Four months after surgery the pulmonary function was still significantly reduced. On the second and fourth postoperative day all patients had atelectasis visible on CT. A single session of deep breathing exercises performed with or without a mechanical device caused a significant reduction in atelectasis and an improvement in oxygenation. No major differences between deep breathing performed with or without a blow bottle or IR-PEP-device were found, except for a lesser decrease in total lung capacity in the blow bottle group on the fourth postoperative day. Patients who performed deep breathing exercises after CABG had significantly smaller atelectasis and better pulmonary function on the fourth postoperative day compared to a control group who performed no exercises.

INTRODUÇÃO: Técnicas de expansão pulmonar são empregadas rotineiramente na recuperação da função pulmonar no pós-operatório de cirurgia cardíaca valvar. Nossa hipótese é que as técnicas de exercícios respiratórios e incentivador inspiratório apresentam efeitos de não inferioridade na função pulmonar quando aplicadas em pacientes avaliados por um escore de risco, que apresentam características de disfunção pulmonar pós-operatória e foram classificados em nível 1 de assistência fisioterapêutica. OBJETIVOS: a) comparar a função pulmonar de pacientes com disfunção pulmonar pós-operatória, submetidos às técnicas de exercícios respiratórios e de incentivador inspiratório no pós-operatório de cirurgia valvar mitral; b) estudar a influência do tipo de lesão valvar mitral, estenose e insuficiência, na evolução da função pulmonar c) comparar a evolução da função pulmonar entre pacientes com hipertensão arterial pulmonar grave e não grave. MÉTODOS: Dados foram coletados no préoperatório, no dia do retorno do paciente à Enfermaria (pós-operatório) e 5 dias após a aplicação das técnicas de expansão pulmonar. Os pacientes foram randomizados para os grupos EXE (exercícios respiratórios) e IS (incentivador inspiratório) realizando três séries de exercícios com 10 repetições, seguidas de tosse, exercícios de mobilização e deambulação. A função pulmonar foi avaliada pela espirometria, oxigenação, pressões musculares respiratórias máximas e presença de colapso pulmonar utilizando radiografias de tórax. Análise estatística utilizou ANOVA para medidas repetidas, teste qui-quadrado ou de Fisher, teste t-Student para nível de significância p < 0,05. RESULTADOS: De 153 pacientes 116 foram incluídos e classificados como nível 1 da assistência fisioterapêutica com 59 pacientes (51%) no grupo de EXE e 57 (49%) no grupo IS. Não houve diferenças estatisticamente significantes entre os grupos, exceto para o movimento toracoabdominal que no grupo EXE apresentou um maior número de casos com recuperação mais precoce. A função pulmonar reduziu significantemente no pós-operatório, com recuperação parcial no 5ºdia (p < 0,05). Frequências cardíaca e respiratória mantiveram-se elevadas (p < 0,05). As taxas de colapso pulmonar antes e após o estudo foram de 61% e 43% no grupo EXE e de 51% e 35% no grupo de IS. Não houve diferenças estatisticamente significantes quando se comparou os pacientes com estenose e insuficiência mitral. Pacientes com PAP >= 50 mmHg (n=55) apresentaram padrão ventilatório restritivo leve e menor oxigenação no préoperatório. CONCLUSÕES: A evolução da função pulmonar dos grupos EXE e IS demonstra não inferioridade entre as técnicas no pós-operatório de cirurgia valvar mitral com disfunção pulmonar, classificados por um sistema de avaliação fisioterapêutica. A recuperação da função pulmonar não apresentou diferenças entre estenose e insuficiência mitral. A presença de hipertensão pulmonar grave não influenciou a evolução da função pulmonar dos pacientes em pós-operatório de cirurgia valvar mitral / INTRODUCTION: Pulmonary expansion techniques are routinely used in the recovery of pulmonary function in the postoperative period of heart valve surgery. Our hypothesis is that the techniques of breathing exercises and incentive spirometry present effects of non-inferiority in pulmonary function when applied in patients evaluated by a risk score, which present postoperative pulmonary dysfunction features and were classified as level 1 of physiotherapeutic assistance. OBJECTIVES: a) to compare the pulmonary function of patients with postoperative pulmonary dysfunction, submitted to the techniques of breathing exercises and incentive spirometry in the postoperative mitral valve surgery; b) to study the influence of the type of mitral valve disease, stenosis and regurgitation in the pulmonary function evolution; c) to compare the pulmonary function evolution between patients with severe and non-severe pulmonary arterial hypertension. METHODS: The data were collected in the preoperative, on the return to the patient\'s ward (postoperative) and 5 days after intervention of the techniques of lung expansion. The patients were randomized to the EXE group (breathing exercises) and IS group (incentive spirometry) performed three sets of exercises with 10 repetitions, followed by cough, mobilization exercises and ambulation. Pulmonary function was assessed by spirometry, oxygenation, maximal respiratory muscle pressures and pulmonary collapse using chest X-rays. The statistical analysis ANOVA for repeated measures, chi-square test or Fisher, Student\'s t-test for significance level of p < 0.05. RESULTS: Of 153 patients 116 were included and classified as level 1 physiotherapeutic assistance with 59 patients (51%) in the EXE group and 57 (49%) in the IS group. There were no statistically significant differences between groups, except for the thoracoabdominal motion in the EXE group had a greater number of cases with earlier recovery. Lung function decreased significantly in the postoperative period, with partial recovery at 5th day of intervention (p < 0.05). Heart and respiratory rate remained high (p < 0.05). The lung collapse rates before and after the study were 61% and 43% in the EXE group and 51% and 35% in IS group. There were no statistically significant differences when we compared the patients with stenosis and mitral regurgitation. PAP >= 50mmHg patients (n= 55) had mild restrictive ventilatory pattern and reduced oxygenation in the pre-operative. CONCLUSIONS: The evolution of pulmonary function of EXE and IS groups with pulmonary dysfunction, classified by physiotherapeutic assessment system showed non-inferiority between techniques in the mitral valve surgery postoperative. The recovery of pulmonary function was not different between mitral stenosis and regurgitation. The presence of severe pulmonary hypertension no affects the evolution of pulmonary function in patients in the postoperative mitral valve surgery

Introdução: A Abertura e fechamento alveolar a cada ciclo respiratório (TR) é mecanismo de lesão pulmonar associada à ventilação mecânica. É frequente, especialmente em pacientes com lesão pulmonar aguda/ sindrome do desconforto respiratório agudo, mas pode ocorrer em pulmões normais, devido à pressão expiratória final positiva (PEEP) insuficiente. A fração inspirada de oxigênio (FiO2) também pode ter um papel na modulação da lesão pulmonar: frações mais baixas, em situação de relação ventilação perfusão (V/Q) crítica, podem retardar o colapso alveolar. A Tomografia de Impedância Elétrica (TIE) é uma nova ferramenta de imagem não invasiva, à beira do leito, que reconstrói imagens transversas da resistividade dos tecidos torácicos, obtidas a partir de uma corrente elétrica injetada por eletrodos colocados circunferencialmente no tórax. Atualmente, o padrão ouro de detecção de TR é a tomografia computadorizada (TC), que utiliza radiação, transporte de pacientes para sua execução, exigindo manobras que podem ocasionar a instabilização dos pacientes. Hipótese deste estudo: é possível detectar e quantificar a ocorrência de TR com TIE. Métodos: 7 suinos traqueostomizados, sob sedação, bloqueio neuromuscular e ventilação mecânica, foram submetidos a manobra de recrutamento alveolar (MRA) em pressão controlada, com pressão platô=50 cmH2O, PEEP=35 cmH2O, aplicada por 2 minutos. Seguiu-se ventilação com volume controlado, posição supina, volume corrente (VT) = 10 ml/kg, fluxo 10l/min FR=10irpm, FiO2=100% e PEEP decremental (20-10-3cmH2O), em passos de 10 minutos. Ao final de cada passo, os animais foram submetidos a uma pressão positiva contínua sobre as vias aéreas em dois níveis, quando se procedeu à TC: pressão de platô (representando inspiração) e PEEP (expiração). Imagens de TIE foram adquiridas continuamente. Os animais foram submetidos à nova MRA, repetindo-se o protocolo em FiO2=40%. Após lesão pulmonar (lavagem pulmonar com SF 0,9% até atingir SpO2< 95%), os passos acima foram repetidos. Para detecção de TR pela TIE, dois métodos foram testados, um método original proposto por este estudo, baseado nas variações de complacência regional (pixel a pixel) ao longo do volume corrente (Método1) e um método descrito em estudo recente por Putensen et al. (Método2). Ambos foram comparados à TC. Resultados: Ocorreu colapso progressivo durante PEEP decremental, sempre maior na FiO2=100% (versus 40%) e após lesão (versus pré-lesão) para as PEEPs correspondentes. A análise de regressão linear, Métodos 1 e 2 para TR em relação à TC evidenciou; Método 1 - R²=0,578 e Método 2 - R²=0,409. As correlações foram melhores quando se considerou apenas as medidas a 100%: R²=0,756 (Método 1) e R2=0,646 (Método 2). Curva ROC; Método 1- área sob a curva: 0,86 e Método2 - 0,79. Regressão logística; Método1 superior ao Método2. Pela ANOVA avaliamos PEEP, lesão, FiO2 e P.Platô na detecção de TR pela TC e Método1..A principal difrerença foi não haver influência da FiO2 sobre TR, Método1 Conclusão: O Método 1 foi superior ao Método2 na detecção de TR, com sensibilidade e especificidade suficiente para se avaliar a utilização clínica. A detecção de TR pelo Método1, não foi influenciada pela FiO2, ao contrário da TC. Estes achados foram compatíveis com os resultados de mecânica pulmonar ( pressão de platô). Portanto, o Método1 foi mais sensível que a TC, pois foi capaz de detectar TR mesmo em situações de ventilação pouco acima do V/Q crítico nas situações de FiO2 de 40%, ao contrário da TC. A TIE não sofreu alterações como o efeito de volume parcial como a TC / Introduction: Cyclic opening and closure of alveolar units during the respiratory cycle, or tidal recruitment (TR), is a harmful mechanism of ventilation induced lung injury. It is frequent, especially in acute lung injury and acute respiratory distress syndrome patients, but can occur in normal lungs under mechanical ventilation, because of an insufficient PEEP. Oxygen concentration (FiO2) can modulate collapse and low FiO2 can delay it. Electrical Impedance tomography (EIT) is a noninvasive imaging tool that reconstructs a cross-sectional image of lungs regional resistivity using electrodes placed around the thorax. EIT is a useful imaging tool for regional ventilation monitoring, as proved by many studies. We hypothesized that is possible to detect and quantify the occurrence of TR by EIT. Seven pigs tracheostomized, sedated and using neuromuscular blockade were submitted to mechanical ventilation. A recruitment maneuver (RM) using plateau pressure = 50cmH2O and positive end expiratory pressure (PEEP) = 35cmH2O for 2 minutes was applied. After, animals were ventilated in volume controlled ventilation mode (VCV), with a tidal volume (Vt) =10ml/kg, inspiratory flow=10l/min, respiratory frequency=10irpm, FiO2=100%. Decremental PEEP (20-10-3cmH2O) steps were applied with 10 minutes intervals between them. Thoracic computed tomography (CT) images were done with a continuous positive airway pressure (CPAP) = Plateau pressure achieved in VCV and PEEP applied, simulating an inspiration and expiration respectively. EIT was acquired continuously during the protocol. RM was repeated and then protocol was repeated, using FiO2=40%. Lung injury was induced (with lung lavage - SF 0.9% until SpO2< 95%). After protocol was repeated including both FiO2. Two TR detectors were tested; an original imaging tool created by our group (Method 1) and a second imaging tool created in a recent study by Putensen. (Method 2). Both methods were compared to CT. Results: A progressive alveolar collapse during decremental PEEP was observed, always greater with FiO2=100% (versus FiO2=40%) and after lung injury (versus before lung injury). Linear regression analysis for Methods 1 and 2 showed for Method1 R2=0.578 and Method 2 R2=0,409. Correlations were better when FiO2=100% was considered individually; Method1 - R²=0,756 and Method2 - R²=0,646. ROC curve presented an area under the curve better for Method1 (0,86) related to Method2 (0,79). Logistic regression also showed better result for Method1. ANOVA was used to test influence of variables as PEEP, lung lesion, FiO2 and Plateau pressure on tidal recruitment. Method1 and CT were tested. The main difference between them was that Method 1 was not influenced by FiO2. Conclusion: Method 1 was superior than 2 for TR detection with sufficient specificity and sensibility for a trial on clinical application. Tidal recruitment detection by Method1 was not influenced by FiO2, but it was for CT, what was supported by results of lung mechanic (plateau pressure). Under lower FiO2 (40%) occurred an underestimation of TR by CT, once the change in ventilation occurs even in lower FiO2 which is not detected by CT. CT is also influenced by partial volume effect, what didn´t occurred with EIT

Introdução: As estratégias ventilatórias protetoras têm contribuído para a redução da letalidade da Síndrome do Desconforto Respiratório Agudo (SDRA), mas ainda está em debate qual, entre as diversas existentes, é a mais eficaz. A estratégia ARDSNet, muito utilizada na prática clínica, prioriza a redução do volume corrente para minimizar a hiperdistensão. As estratégias Open Lung Approach (OLA), além de procurarem reduzir a hiperdistensão, buscam minimizar o colapso pulmonar para evitar a atelectasia cíclica. Os métodos para ajuste da PEEP ideal nas estratégias OLA apresentam imperfeições: difícil implementação, não permitem avaliação regional do pulmão ou não podem ser realizados a beira leito. Uma estratégia OLA guiada por Tomografia de Impedância Elétrica (TIE) que permite a avaliação regional pulmonar de modo contínuo e a beira leito pode trazer benefícios. Objetivo: Comparar os efeitos fisiológicos (imagem, mecânica e trocas gasosas) ao longo de 42 h entre duas estratégias ventilatórias protetoras em um modelo suíno de SDRA (estratégia ARDSNET X estratégia guiada por TIE: (PEEPTIE). Comparar a mecânica pulmonar e troca gasosa nas duas estratégias ao final das 42 h de ventilação, em uma mesma condição de ventilação, para avaliar efeitos duradouros das estratégias sobre o parênquima pulmonar. Métodos: Sete porcos foram submetidos a ventilação mecânica por 42 horas em cada uma das duas estratégias. A lesão pulmonary foi induzida com lavagem de solução fisiológica associada a ventilação lesiva. No grupo PEEPTIE, a PEEP foi ajustada pela TIE após manobra de recrutamento, mantendo o pulmão com o mínimo de colapso menor que 5%), enquanto que na estratégia ARDSNet era ajustada através da tabela PEEPxFiO2. O volume corrente foi mantido entre 4-6ml/Kg em ambas estratégias, com a pressão de platô menor que 30 cmH2O. Resultados: Oxigenação e mecânica pulmonary eram semelhantes em ambos os grupos após a lesão pulmonar. Durante as 42h de protocolo, a troca gasosa foi significativamente maior no grupo PEEPTIE quando comparado ao grupo ARDSNet tanto no início (p< 0.01) quanto ao final do protocolo(p< 0.01). A PEEP inicial não foi diferente nas duas estratégias (p= 0.14), mas foi significantemente maior no grupo PEEPTIE (p< 0.01) em grande parte do período de 42 h e também ao final. Não houve diferença na pressão de platô entre os grupos (p=0.05). O delta de pressão foi significativamente maior no grupo ARDSNet no começo (p= 0.03) e ao final do protocolo (p= 0.00). Atelectasia cíclica (p < 0.01) e a porcentagem de tecido não-aerado (p= 0.029) foram significativamente maiores no grupo ARDSNet. Ao final do protocolo, nos mesmos ajuste de ventilação, a complacência pulmonar global (p=0.021) e regional (p= 0.002) foram significativamente maiores no grupo PEEPTIE, bem como a troca gasosa (p= 0.048). Conclusões: a estratégia PEEPTIE, quando comparada a estratégia ARDSNet determinou melhor oxigenação, menor grau de colapso e de atelectasia cíclica, além de melhor mecânica pulmonar, tanto global, quanto regional. Esta melhora foi mantida ao final das 42 horas, quando os dois grupos eram ventilados com os mesmos ajustes, sugerindo que a estratégia PEEPTIE determinou menor dano pulmonar / Introduction: Protective ventilatory strategies have contributed for the reduction in Acute Respiratory Distress Syndrome (ARDS) mortality, but so far there is still debate which strategy is more effective. The ARDSNet strategy, used widely in the clinical practice, emphasizes in tidal volume reduction to minimize hiperdistension. The Open Lung Approach (OLA), besides the reduction of hiperdistension, emphasizes reduction of lung collapse to avoid tidal recruitment. The methods to adjust ideal PEEP in the OLA strategies have some imperfections: difficult implementation, do not allow regional lung evaluation or cant be performed at the bedside. The OLA strategy guided by Electrical Impedance Tomography (EIT) which allows a continuous and regional lung evaluation can bring benefits. Objective: Compare physiological effects (image, mechanics and gas exchange) during a period of 42 hours between two protective ventilatory strategies in an ARDS suine model (ARDSNet strategy x strategy guided by EIT PEEPTIE). Compare lung mechanics and gas exchange in both strategies at the end of 42 hours of ventilation, in the same ventilation condition, to evaluate the strategies longtime effects on lung parenchyma. Methods: Seven suines were submitted to mechanical ventilation for 42 hours in each ventilator strategy. Lung injury was induced by saline lavage associated to injurious mechanical ventilation. In the PEEPTIE arm, PEEP was selected by the electrical impedance tomography after a recruitment maneuver, trying to keep lung collapse at minimum, while the ARDSnet group followed a PEEPxFiO2 table. Tidal volume of 4-6ml/kg was maintained in both strategies, with a plateau pressure not higher than 30 cmH2O. Results: Oxygenation and lung mechanics were equally impaired in both arms after injury. During the 42 hours of protocol, gas exchange was significantly higher in the PEEPTIE arm as compared to the ARDSNet arm in the beginning (p< 0.01) and at the end of the protocol (p< 0.01). PEEP at the beginning of the protocol was similar between groups (p= 0.14), but at most part of the protocol and at the end, PEEP was significantly higher in the PEEPTIE arm (p< 0.01).There were no difference in plateau pressure (p=0.06). Driving pressure was significantly higher in the ARDSNet arm at the beginning (p= 0.03) and at the end (p= 0.00). Tidal recruitment was significantly higher in the ARDSNet arm (p < 0.01), and a higher percentage of non-aerated lung tissue (p= 0.029). At the end of the protocol, global lung compliance was significantly higher in the PEEPTIE arm (p=0.021), as for regional lung compliance (p= 0.002) and gas exchange (p= 0.048). Conclusion: The PEEPTIE strategy when compared to the ARDSNet strategy determined better gas exchange, lower percentage of collapse and tidal recruitment, besides better lung mechanics (global and regional). This improvement was maintained at the end of the 42 hours, when both groups were ventilated with the same parameters, suggesting that the PEEPTIE strategy determined less lung injury

Quantitative computertomographische Studie zu den pulmonalen Auswirkungen intramuskulär applizierten Xylazins beim Schaf Einleitung. α2-Agonisten wie z.B. Xylazin werden in der veterinärmedizinischen Praxis häufig zur Se-dierung eingesetzt. Dabei ist für das Schaf eine besonders ausgeprägte Sensibilität gegenüber Xylazin nachgewiesen. Bisher nur unzureichend untersucht wurde der Einfluss der Applikationsform des α2-Agonisten Xylazin (intravenöse versus intramuskuläre Injektion) auf den Ausprägungsgrad der entste-henden Lungenveränderungen. Ziele der Untersuchungen. Ziel der vorliegenden Arbeit war es, die Xylazin-induzierten pulmonalen Reaktionen nach intramuskulärer Applikation zu quantifizieren und mit den Auswirkungen einer intrave-nösen Gabe beim Schaf zu vergleichen. Um wissenschaftlich konsequent zu arbeiten, wurde weiterhin die Wirkung der in Xylazin-Präparaten enthaltenen sonstigen Bestandteile untersucht. Material und Methode. Als Studientiere wurden sieben weibliche Schafe der Rasse Merinoland zwei-malig in einem Abstand von acht Wochen untersucht. Bei diesen Tieren handelte es sich um die Scha-fe, welche in einem vorausgegangenen Projekt zu den pulmonalen Wirkungen von intravenös appliziertem Xylazin in identischer Dosierung am deutlichsten reagiert hatten. Nach Prämedikation der Tiere mit Midazolam (0,25 mg/kg KM) und Sufentanil (0,6 µg/kg KM) wurde die Narkose mit Propofol aufrechterhalten (5-10 mg/kg KM/h). Nach abgeschlossener Instrumentierung wurden die Schafe in Rückenlage im Computertomographen positioniert und mit einer inspiratorischen Sauerstoffkonzentration von 100 Vol.-% beatmet. Zur Reduktion lagerungsbedingter Atelektasen wurde vor Versuchsbeginn ein Recruit¬ment¬ma¬nö¬ver (druckkontrollierte Beatmung, inspiratorischer Spitzendruck 60 cmH2O, PEEP 40 cmH2O, Atemfrequenz 10/min, Dauer zwei Minuten) durchgeführt. Nach abgeschlossenem Recruitmentmanöver wurden die Schafe bis zum Ende des Versuchsabschnittes volumenkontrolliert beatmet (Atemzugvolumen 8 ml/kg KM, PEEP 10 cmH2O, Adjustierung der Atemfrequenz, Ziel endexspiratorische Kohlendioxidkonzentration etwa 4,5 Vol.-%). Im Versuchsabschnitt „i.m.“ wurde Xylazin intramuskulär in einer Dosierung von 0,3 mg/kg KM injiziert. 10 Minuten vor sowie 5, 15, 30 und 60 Minuten nach der Xylazin-Injektion wurden computertomographische Untersuchungen des Thorax durchgeführt. Im Versuchsabschnitt „Vehikel“ wurde den Schafen eine dem verwendeten Xylazin-Präparat analoge, jedoch Xylazin-freie Lösung intravenös appliziert (enthält 1 mg/ml des Konservierungsstoffs Methyl-para-hydroxybenzoat). Als Dosis wurde eine der Xylazin-Gabe entsprechende Dosis von 0,015 ml/kg KM gewählt. Zusätzlich wurde 45 Minuten nach Versuchsbeginn Xylazin® 2 % in einer Dosis von 0,3 mg/kg KM intravenös injiziert. Die computertomographischen Untersuchungen wurden 10 Minuten vor sowie 5, 15, 30 Minuten nach erfolgter Injektion des Vehikel-Präparates und 5 Minuten nach erfolgter Injektion von Xylazin® durchgeführt. Unter Anwendung der Extrapolationsmethode wurden mit der quantitativen computertomographischen Analyse jeweils das totale Lungenvolumen (Vtot), das totale Lungengewicht (Mtot) und der Anteil der nicht belüfteten Lungenmasse (% Mnon) bestimmt. Dabei galt ein Abfall im totalen Lungenvolumen als Nachweis für Atelektasen, ein Anstieg im totalen Lungengewicht war gleichbedeutend mit der Entstehung eines Lungenödems. Als klinisch relevant galt eine Zunahme der totalen Lungenmasse um 100 g. In beiden Versuchsabschnitten wurden mittels arterieller Blutgasanalysen zusätzlich der arterielle Sauerstoff- und Kohlenstoffdioxidpartialdruck (PaO2, PaCO2) erfasst. Ergebnisse. Vor der intramuskulären Xylazin-Gabe wurden folgende Medianwerte ermittelt: Vtot: 4220 ml, Mtot: 1280 g, % Mnon: 3 %, PaO2: 443 mmHg, PaCO2: 48 mmHg. Nach intramuskulärer Xylazin-Injektion zeigten sich die nachfolgenden statistisch signifikanten Maximaländerungen: Vtot-Abfall: 516 ml (Interquartilbereich 408-607), Mtot bzw. % Mnon-Zunahme: 108 g (Interquartilbereich 70-140) bzw. 15 % (Interquartilbereich 8-24) PaO2-Abfall: 280 mmHg (Interquartilbereich 200-346), PaCO2-Anstieg: 17 mmHg (Interquartilbereich 7-27). Die intramuskuläre Gabe von Xylazin verursachte im Vergleich zur intravenösen tendenziell, aber statistisch nicht signifikant, geringere Abnahmen im totalen Lungenvolumen sowie eine tendenziell, aber statistisch nicht signifikant geringere Zunahme im Anteil der nicht belüfteten Lungenmasse. Des Weiteren konnte ein statistisch signifikant geringerer Abfall im arteriellen Sauerstoffpartialdruck bei intramuskulär erfolgter Injektion nachgewiesen werden. Die Xylazin-induzierte Hypoxämie erreichte unter Beatmung mit 100 Vol.-% Sauerstoff auch nach intramuskulärer Gabe des α2-Agonisten im Mittel einen moderaten Ausprägungsgrad, wobei 50 % der Studientiere sogar eine schwere Belüftungsstörung zeigten (PaO2 < 100 mmHg). Entsprechend dem Schweregrad der durch den α2-Agonisten induzierten Belüftungsstörung trat eine Hyperkapnie auch nach intramuskulärer Xylazin-Gabe auf. Auch die korrespondierenden % Mnon-Zunahmen erreichten bei intramuskulärer Xylazin-Injektion neben der statistischen Signifikanz erhebliche klinische Relevanz. So waren im Mittel 18 % (Interquartilbereich 10-28) des Lungengewebes nach intramuskulärer Gabe des α2-Ago¬nis¬ten nicht belüftet. Bei jeweils 50 % der Tiere konnte für beide Applikationsformen ein klinisch relevantes Lungenödem nachgewiesen werden. Eine Reaktion der Versuchstiere auf die sonstigen im Xylazin-Präparat enthaltenen Bestandteile konnte ausgeschlossen werden. So konnte für keinen der untersuchten Parameter eine statistisch signifikante Änderung nach Injektion der Vehikel-Lösung nachgewiesen werden. Statistisch signifikante Zu- bzw. Abnahmen in den untersuchten Parametern konnten eindeutig der Wirkung des α2-Agonisten Xylazin zugewiesen werden. Schlussfolgerungen. Trotz quantitativ geringerer Ausprägung in den detektierten Änderungen von Vtot, PaO2 und % Mnon zeigten die Xylazin-induzierten pulmonalen Reaktionen bei der Mehrzahl der Studientiere auch nach intramuskulär erfolgter Applikation des α2-Agonisten erhebliche klinische Relevanz. Ein zeitlich verzögertes Eintreten im Vergleich zur intravenösen Gabe des α2-Agonisten konnte nur für die Formation des Xylazin-induzierten Lungenödems festgestellt werden. Analog zu den Ergebnissen des vorausgegangenen Projektes zur Wirkung von intravenös verabreichtem Xylazin, kann das morphologische Bild der Xylazin-induzierten Lungenveränderungen durch eine Koexistenz von Atelektasen und Lungenödem beschrieben werden. Derzeit konnte noch kein logisches Muster gefunden werden, dass die interindividuelle Variabilität in der Reaktion auf Xylazin beim Schaf aufzuklären vermag. Ebenso ist der Erkenntnisstand bezüglich einer möglicherweise vorhandenen Rasseabhängigkeit bis dato nicht ausreichend, um im Vorfeld die Sensibilität gegenüber Xylazin bei einem Schaf abschätzen zu können. Demzufolge muss beim Schaf auf der Grundlage der vorliegenden Ergebnisse im Einzelfall auch nach einer intramuskulären Xylazin-Gabe mit einer Dosierung von 0,3 mg/kg KM von schwerwiegenden Lungenveränderungen ausgegangen werden. Sofern Schafe als Tier-Modell in der experimentellen Lungenforschung verwendet werden, sollte aufgrund der Gefahr von fehlerhaften Forschungsergebnissen sowohl auf den intramuskulären Einsatz von Xylazin zur Prämedikation verzichtet werden als auch auf die intravenöse Verabreichung des α2-Agonisten als Narkosebestandteil. Um in der Praxis zukünftig unnötiges Leiden oder gar Versterben von Tieren verhindern zu können, muss die Problematik der Xylazin-induzierten Lungenveränderungen beim Schaf weiter verfolgt und näher erforscht werden.

Das Auftreten pulmonaler Belüftungsstörungen nach Injektion von Xylazin beim Schaf ist in der wissenschaftlichen Literatur an Einzeltieren beschrieben. Der dabei noch ausstehende Nachweis eines postulierten Lungenödems anhand objektiver Parameter in statistisch relevanter Anzahl wurde in der hier vorliegenden Arbeit angestrebt. Weiterhin wurden ein Einfluss der wiederholten Exposition und eine Dosisabhängigkeit überprüft. Zur Bearbeitung dieser Fragen wurden 16 weibliche Merinolandschafe dreimalig in einem Abstand von 8 Wochen untersucht. Nach Prämedikation mit Midazolam (0,25 mg/kg) und Sufentanil (0,6 µg/kg) erfolgte die Allgemeinanästhesie mit Propofol (5-10 mg/kg/h). Zu den ersten beiden Versuchsabschnitten wurde Xylazin in einer Dosis von 0,15 mg/kg, im dritten Versuchsdurchgang in Höhe von 0,3 mg/kg intravenös verabreicht. Jeweils 10 Minuten vor und 5, 15, 30 Minuten nach Applikation von Xylazin wurden computertomographische Untersuchungen durchgeführt. Mit Hilfe der quantitativen computertomographischen Analyse konnte das totale Lungengewicht, der Anteil nicht belüftetes Lungengewicht und das totale Lungenvolumen ermittelt werden. Zusätzlich wurden mittels arterieller Blutgasanalysen der arterielle Sauerstoff- und Kohlenstoffdioxidpartialdruck bestimmt. In der dieser Arbeit zu Grunde liegenden Annahme nimmt im Falle eines Lungenödems das totale Lungengewicht bei konstantem Lungenvolumen zu. Eine Zunahme des totalen Lungengewichts war in allen drei Versuchsdurchgängen statitisch signifikant nachweisbar. Im Vergleich zu den Angaben in der Literatur wurden dabei jedoch keine Zunahmen in Höhe eines klinisch relevanten Lungenödems erreicht. Unerwartet konnte zusätzlich ein signifikanter Rückgang des totalen Lungenvolumens detektiert werden. Weiterhin waren bereits 5 Minuten nach Xylazininjektion bis zu einem Drittel des totalen Lungengewichts nicht belüftet. Diese pulmonalen Belüftungsstörungen nach Applikation von Xylazin beim Schaf wurden aufgrund der vorliegenden Ergebnisse nicht ausschließlich der Entstehung eines Lungenödems zugeordnet. Die detektierte Reduktion des totalen Lungenvolumens bei konstanter Beatmung kann nur durch Atelektasen begründet werden. Entsprechend dem Ausmaß der detektierten pulmonalen Reaktionen nach Xylazingabe wurden eine schwere Hypoxämie sowie eine Hyperkapnie festgestellt. Durch die mehrfache Exposition von Xylazin erfolgte der Nachweis der Wiederholbarkeit dieser Ergebnisse. Eine Dosisabhängigkeit des Ausprägungsgrades der pulmonalen Befunde hingegen konnte nicht statistisch signifikant bestätigt werden. Anhand der hier vorliegenden Ergebnisse muss die Ätiologie der pulmonalen Veränderungen nach Injektion von Xylazin beim Schaf neu durchdacht und in weiteren Studien verfolgt werden. Einflussfaktoren wie die Form der Applikation oder eine genetische Prädisposition gilt es in Zukunft zu analysieren. Neben der klinischen Anwendung von Xylazin sind die erarbeiteten Resultate relevant für humanmedizinische Fragestellungen in der Pulmologie. Dort sollte in der häufigen Verwendung des Schafes als Tiermodell in Hinblick auf mögliche Interaktionen mit den experimentellen Ergebnissen auf die Applikation von Xylazin verzichtet werden.

<p>UVOD: Drenaža grudnog ko&scaron;a nakon resekcija pluća je osnovni grudno hirur&scaron;ki postupak, koji omogućuje pro&scaron;irenje (reekspanziju) pluća iz kolabiranog stanja, evakuaciju vazduha, krvi i izliva iz pleuralnog prostora i potpomognuta je primenom aspiracije na drenove (sukciona ili aspiraciona drenaža). Iako je drenaža&nbsp; svakodnevna grudno hirur&scaron;ka procedura, postupak sa drenovima je zasnovan prvenstveno na iskustvu, a manje na osnovu naučnih studija. Pri mirnom disanju inspiratorni pritisak u pleuralnom prostoru je prosečno - 8 cm H2O, a ekspiratorni - 4 cm H2O. Pri forsiranom disanju pritisci mogu dostići - 50 cm H2O i +70 cm H2O. Na osnovu tih fiziolo&scaron;kih podataka, većina hirurga primenjuje aspiraciju od - 10 do - 40 cm H2O. Koncepta pleuralnog deficita - disproporcije volumena preostalog plućnog tkiva i zapremine grudnog ko&scaron;a doveo je do razvoja tehničkih postupaka za postizanje nove fiziolo&scaron;ke ravnoteže u pleuralnom prostoru i razmatranja rutinske primene podvodne (pasivne) drenaže nakon resekcija pluća. Pritisak na zdravstvenu službu za smanjenje tro&scaron;kova i skraćenje postoperativne hospitalizacije uz mogućnost rane mobilizacije pacijenta čine podvodnu drenažu zanimljivom alternativom tradicionalno prihvaćenoj aktivnoj aspiraciji na drenove.&nbsp; CILJ: Da se utvrdi da li aplikacija aktivne aspiracije na drenove nakon lobektomije pluća u poređenju da podvodnom drenažom ima povoljno terapijsko dejstvo na postizanje i održavanje reekspanzije pluća; Da se kvantitativno uporede različiti modovi aktivne aspiracije preko drenova; Da se uporedi dužina hospitalizacije i pojava hirur&scaron;kih i nehirur&scaron;kih komplikacija između grupa ispitanika kod kojih se primenjuje podvodna (pasivna) drenaža i aspiracija preko drenova. METODOLOGIJA: Prospektivna studija bez randomizacije obuhvatila je 301 ispitanika kojima je načinjena lobektomija pluća zbog karcinoma pluća na Klinici za grudnu hirurgiju Instituta za plućne bolesti Vojvodine u Sremskoj Kamenici u periodu od 01.01.2008. - 28.02.2010. godine. Beleženi su i analizirani podaci o preoperativnom stanju: plućnoj funkciji, prethodno primljenoj neoadjuvantnoj hemioterapiji i pridruženim bolestima. Analizirani su hirur&scaron;ki operativni podaci o postojanju buloznog emfizema, adhezija u pleuralnom prostoru, anatomskoj vrsti lobektomije, dodatnim hirur&scaron;kim procedurama i postojanju gubitka vazduha na kraju operacije. Analizirani su postoperativni podaci o secernaciji na drenove tokom prva 24 h i ukupno, trajanju gubitka vazduha na drenove u danima, ukupnom trajanju drenaže, ukupnom trajanju hospitalizacije, pojavi produženog gubitka vazduha na dren definisanog kao gubitak duže od 7 dana, potrebi za redrenažom grudnog ko&scaron;a (broj drenova upotrebljenih za redrenažu), kompletnost reekspanzije pluća pre vađenja drenova, pojavi drugih hirur&scaron;kih komplikacija, pojavi op&scaron;tih medicinskih komplikacija i pojavi kasnih komplikacija &ndash; vi&scaron;e od 30 dana nakon operacije ili nakon otpusta. Prvu grupu ispitanika sačinjavaju pacijenti kojima je načinjena lobektomija pluća, nakon čega je aplikovana aspiracija od -20 cm vodenog stuba do klemovanja i vađenja drenova. Drugu grupu ispitanika sačinjavaju pacijenti kojima je aplikovana aspiracija od -20 cm vodenog stuba na dan operacije i zatim -10 cm vodenog stuba do klemovanja i vađenja drenova. Treću grupu ispitanika sačinjavaju pacijenti kojima je načinjena lobektomija pluća, nakon čega je aplikovana aspiracija od -20 cm vodenog stuba na dan operacije i zatim podvodna drenaža do klemovanja i vađenja drenova. Četvrtu grupu ispitanika sačinjavaju pacijenti kojima je načinjena lobektomija pluća, nakon čega je aplikovana aspiracija od -20 cm vodenog stuba na dan operacije i zatim dnevna procena i modifikacija na sledeći način: aspiracija od -20 cm vodenog stuba do postizanja reekspanzije pluća, zatim postepeno smanjenje aspiracije po nahođenju operatera do klemovanja i vađenja drenova. REZULTATI: Između grupa ispitanika ne postoji statistički značajna razlika po starosti (p=0,77),&nbsp; parametrima plućne funkcije: vrednost FEV1 (p=0,6316), vrednost ITGV (p=0,6202), vrednost TLC (p=0,6922) i za vrednost RV ne postoji razlika (p=0,6552). Razlika ne postoji između grupa ni u učestalosti pridruženih bolesti (p=0,4522). Grupe su međusobno homogene po preoperativnim parametrima. Snižen FEV1 u ukupnoj populaciji pacijenata nije uticao na pojavu produženog gubitka vazduha (P=0,571), kao ni povi&scaron;enje ITGV (P=0,22), RV (p=0,912), niti vrednost TLC (0,521). Upoređene su međusobno osnovne vrste lobektomija: desna gornja, leva gornja, desna donja, leva donja, srednja lobektomija, kao i donja i gornja bilobektomija desno. Kako je učestalost svake pojedinačne lobektomije u 4 grupe ispitanika mali da bi se uporedile iste lobektomije između grupa, poređenje je moguće samo između anatomski različitih lobektomija kumulativno u svim grupama. Razlika u pojavi produženog gubitka vazduha između različitih lobektomija postoji, ali nije dostigla statističku značajnost (p=0,061). Međutim, kada se analizira svaka lobektomija pojedinačno, uočava se da desna donja bilobektomija ima značajno veću učestalost produženog gubitka vazduha u odnosu na sve ostale lobektomije zajedno (P=0,009). Razlika u dužini drenaže kod&nbsp; različitih lobektomija je dostigla statistički značaj (p=0,0356), kao i u ukupnoj dužini hospitalizacije (p=0,0007). Dodatak resekcije perikarda, grudnog zida ili dijafragme, klinasta resekcija susednog režnja ili sleeve resekcija bronha kao dodatne procedure nisu uticali na pojavu produženog gubitka vazduha (p=0,58). Podaci o učestalosti adhezija u ispitivanoj populaciji pacijenata i njihovom uticaju na pojavu produženog gubitka vazduha daju granične vrednosti. I ovde je broj pacijenata u svakoj pojedinačnoj kategoriji adhezija (postojanje adhezija na skali od 0-3) mali da bi testiranje povezanosti sa produženim gubitkom vazduha moglo dostići statističku značajnost - razlika postoji, ali nije značajna (p=0,065). Radi povećanja statističke snage je izvedeno testiranje za podelu ima ili nema adhezija. Razlika postoji, ali ni ovim testiranjem nije dostignuta statistički značajna razlika (p=0,057). Postojanje buloznog emfizema takođe dovodi do povećanja učestalosti produženog gubitka vazduha, ali ni ovde razlika nije značajna (p=0,063).&nbsp; Primena hemoterapije pre operacije nije dovela do statistički značajne razlike u pojavi produženog gubitka vazduha (p=0,0623) i ukupnoj stopi komplikacija (p=0,088), kao ni dužine hospitalizacije (p=0,2), iako razlika postoji i paradoksalno rezultat je bolji kod pacijenata koji su primili hemioterapiju, &scaron;to može ukazivati na uticaj selekcije pacijenata za operaciju. Između 4 grupe ispitanika nije uočena razlika u potrebi za redrenažom grudnog ko&scaron;a (p=0,101), potrebi za povećanjem nivoa aktivne aspiracije (p=0,326), ukupnoj pojavi komplikacija (p=0,087) i pojavi produženog gubitka vazduha (P=0,323). Razlika postoji i visoko je značajna u dužini trajanja drenaže (p=0,001) i dužini hospitalizacije (P=0,000). Broj drenova (1 ili 2 drena postavljena intraoperativno) nije uticao na pojavu produženog gubitka vazduha (p=0,279), ali je značajno kraća hospitalizacija kod pacijenata sa jednim drenom (p=0,0001). Logistička regresiona analiza je pokazala da je samo donja bilobektomija značajno uticala na pojavu produženog gubitka vazduha na dren, dok nije nađen uticaj aktivne aspiracije na drenove, prisustva adhezija, buloznog emfizema, sniženih vrednosti FEV1, primene redukcije pleuralnog prostora (space reducing), broja drenova i dodatne operacije (resekcije). ZAKLJUČAK: Sprovedenim istraživanjem utvrđeno je da primena aktivne aspiracije na drenove ne pokazuje razliku u odnosu na podvodnu drenažu u postizanju i održavanju reekspanzije pluća nakon lobektomije. Aktivna aspiracija ne utiče na pojavu produženog gubitka vazduha na drenove definisanog kao gubitak vazduha duže od 7 dana, ali utiče na produženje ukupnog trajanja drenaže i hospitalizacije. Nivo aktivne aspiracije ili primena dnevnih modifikacija nivoa aspiracije ne utiče na rezultate lečenja.&nbsp; U ovom istraživanju preoperativna plućna funkcija, kao ni preoperativna hemoterapija ne utiču na pojavu produženog gubitka vazduha na drenove. Desna donja bilobektomija u odnosu na sve druge lobektomije dovodi do če&scaron;će pojave produženog gubitka vazduha, produžene drenaže i hospitalizacije. Dodatne resekcije okolnih tkiva u sklopu lobektomije ili primena redukcije pleuralnog prostora ne utiču na pojavu produženog gubitka vazduha. Intraoperativni nalaz adhezija u pleuri i buloznog emfizema pluća povećavaju rizik produženog gubitka vazduha, ali je taj uticaj na granici statističke značajnosti. Primena jednog drena nakon lobektomije umesto dva ne utiče na pojavu produženog gubitka vazduha, ali utiče na skraćenje drenaže i hospitalizacije. U multivarijatnoj analizi samo je donja bilobektomija značajno uticala na pojavu produženog gubitka vazduha na dren, dok nije nađen uticaj aktivne aspiracije na drenove, prisustva adhezija, buloznog emfizema, sniženih vrednosti FEV1, primene redukcije pleuralnog, broja drenova i dodatne resekcije okolnih tkiva.</p> / <p>INTRODUCTION: The drainage of the thorax after pulmonary resection is a basic thoracic surgery procedure which enables reexpansion after lung collapse and the evacuation of air, blood and effusion from the pleural cavity. It is supported by the use of drainage aspiration (suction or aspiration drainage). Although drainage is an everyday procedure in thoracic surgery, the use of drains is based mainly on specialist experience and less on scientific research. During calm breathing the inspiratory pressure in the pleural cavity is &ndash; 8cm H2O on average, while the expiratory pressure is &ndash; 4cm H2O. During forced breathing the pressures can reach up to &ndash; 50 cm H2O and + 70 cm H2O. Based on this physiological data, most surgeons apply the aspiration from &ndash; 10 to &ndash; 40 cm H2O. The concept of pleural deficit (the disproportion of the volume of the remaining pulmonary tissue and the volume of the thorax) has attributed to development of new technical procedures in order to achieve a new physiological balance in the pleural cavity. It has also brought upon the consideration of routine underwater seal drainage after pulmonary resection. Underwater seal drainage represents an interesting alternative to the traditional active drainage aspiration, especially considering the need to reduce medical expenses and shorten the postoperative hospitalization period. AIM: To determine whether active drainage aspiration after pulmonary lobectomy has a favorable therapeutic effect on achieving and maintaining pulmonary reexpansion in comparison with underwater seal drainage; to quantitatively compare the different modes of active drainage aspiration; to compare hospitalization duration and surgical and non-surgical complication with groups of patients on whom either underwater seal drainage or aspiration drainage was applied. METHODOLOGY: The prospective study without randomization has covered 301 patients on whom pulmonary lobectomy was performed due to lung carcinoma at the Thoracic Surgery Clinic of the Institute of Pulmonary Diseases of Vojvodina from 1st January 2008 to 28th February 2010. The data collected in the pre-operative state included: pulmonary function, previous neoadjuvant chemotherapy and comorbidities. In the research, surgical operative data and postoperative data were analyzed. Surgical operative data included information about the bullous emphysema, adhesion in the pleural cavity, anatomic type of lobectomy, additional surgical procedures and air leak after surgery. Postoperative data involved information about amount of fluid on drainage during the first 24 hours and in total, air leak duration in days, total drainage period, overall hospitalization period, prolonged air leak defined as leak longer than 7 days, the need for redrainage of thorax (number of tubes used for redrainage), completeness of pulmonary reexpansion before the end of drainage, other surgical complications, comorbidities and late complications (after more than 30 days following the surgery or release). The first group consists of patients on whom pulmonary lobectomy was performed, after which an aspiration of &ndash; 20 cm H2O was applied before clamping and tube extraction. The second group consists of patients on whom pulmonary lobectomy was performed, after which an aspiration of &ndash; 20 cm H2O was applied on surgery day and again &ndash; 10 cm H2O before clamping and tube extraction. The third group consists of patients on whom pulmonary lobectomy was performed, after which an aspiration of &ndash; 20 cm H2O was applied on surgery day and underwater seal drainage was applied before clamping and tube extraction. The fourth group consists of patients on whom pulmonary lobectomy was performed, after which an aspiration of &ndash; 20 cm H2O was applied on surgery day, and then daily monitored and modified in such a way that an aspiration of &ndash; 20 cm H2O was applied until pulmonary reexpansion and then gradually lowered according to individual surgery experience before clamping and tube extraction. RESULTS: There is no significant statistical difference between groups of patients in: age (p=0.77), FEV1 (p=0.6316), ITGV (p=0.6202), TLC (p=0.6922) and RV (p=0.6552) and comorbidities (p=0.4522). The groups are homogenous in pre-operative parameters. Lowered FEV1 among all patients did not affect prolonged air leak (p=0.571), nor the increase in values of ITGV (p=0.22), RV (p=0.912) and TLC (p=0.5211). The lobectomies that were compared were: upper right, upper left, lower right, lower left, middle, as well as upper and lower right bilobectomy. The comparison was implemented only on anatomically different lobectomies cumulatively among groups, due to the low occurrence of each type of lobectomy in groups. The difference in prolonged air leak does exist, but is not statistically significant (p=0.061). Prolonged air leak has a significantly higher occurrence in lower right bilobectomies (p=0.009). Drainage duration and hospitalization period variations in different kinds of lobectomy are statistically significant (p=0.0356 and p=0.0007, respectively). Additional pericardial, thoracic or diaphragm resection, wedge resection of the neighboring lobe, or sleeve bronchial resection did not affect prolonged air leak (p=0.58). The research has established that the occurrence of adhesion (on a scale 0-3) in patients and bulous emphysema attribute to prolonged air leak (p=0.065 and p=0.063, respectively).&nbsp; Comparison between patients with and without adhesions revealed similar result. Difference exists, but it is not statistically significant (p=0,057).&nbsp; Pre-operative chemotherapy had no statistical significance on prolonged air leak (p=0.0623), total rate of complications (p=0.088), nor hospitalization period (p=0.2). Paradoxically, the treatment was in favor of those patients who had taken pre-operative chemotherapy, which could be due to the selection of patients for surgery.&nbsp; Among the four groups, there was no difference in need for thoracic redrainage (p=0.101), need for increase in level of active aspiration (p=0.326), overall complication occurrence (p=0.087) and prolonged air leak occurrence (p=0.323). There is a statistically significant difference in drainage duration (p=0.001) and hospitalization period (p=0.000). The number of tubes (1 or 2 tubes set intraoperatively) did not affect prolonged air leak occurrence (p=0.279). The hospitalization period in patients with one tube set intraoperatively is significantly shorter (p=0.0001). Logistic regression analysis has shown that only lower bilobectomy had a significant impact on prolonged air leak, unlike active drainage aspiration, the presence of adhesions, bullous emphysema or lowered FEV1 values, pleural cavity space reducing, number of tubes and resection. CONCLUSION: The research has shown: Active drainage aspiration has no difference in effect in achieving and maintaining pulmonary reexpansion after lobectomy when compared to underwater seal drainage; Active drainage aspiration does not affect prolonged air leak, defined as air leak longer than 7 days; Active drainage aspiration has an impact on the overall drainage duration and hospitalization period; The level of active drainage aspiration and daily modification of the mentioned do not affect treatment results; Preoperative pulmonary function does not affect prolonged air leak occurrence; Preoperative chemotherapy does not affect prolonged air leak occurrence; Prolonged air leak and drainage and hospitalization period occur most often in lower right bilobectomies; Nor additional resections nor pleural cavity reduction affect prolonged air leak occurrence; The presence of pleural adhesions and bullous emphysema rarely attribute to the increase of prolonged air leak occurrence; The number of tubes implemented intraoperatively does not affect prolonged air leak occurrence, but it shortens drainage and hospitalization periods; By multivariate analysis, that only lower bilobectomy has a significant impact on prolonged air leak, unlike active drainage aspiration, the presence of adhesions, bulous emphysema or lowered FEV1 values, pleural cavity space reducing, number of tubes and resection.</p>

É sabido que a ventilação mecânica é essencial para oxigenação do sangue e remoção de dióxido de carbono, sendo realizada sobre sedação ou anestesia geral. Contudo, durante à ventilação mecânica, podem ocorrer alterações na estrutura pulmonar caracterizadas por aparecimento de colapso ao final da expiração e zonas de hiperinsuflação alveolar durante a fase inspiratória, podendo levar ao aparecimento de lesão pulmonar associada à ventilação mecânica. Como não existe consenso sobre a melhor estratégia para ventilação mecânica intraoperatória em pequenos animais submetidos a procedimentos cirúrgicos sobre anestesia geral, o objetivo desse estudo foi avaliar a hiperinsuflação pulmonar em diferentes níveis pressóricos nas vias aéreas por meio de tomografia computadorizada em gatos submetidos à anestesia geral. Foram utilizados 17 gatos machos adultos, submetidos à ventilação mecânica a pressão controlada, iniciando a uma pressão de pico de 5cmH2O em \"ZEEP\", subindo escalonadamente 2 cmH2O a cada 5 minutos, até chegar a 15 cmH2O, em seguida, descendo escalonadamente 2 cmH2O a cada 5 minutos, até chegar a 5 cmH2O. A frequência respiratória foi mantida em 15 movimentos por minuto e o tempo inspiratório em um segundo, independente de seu EtCO2. Imediatamente a cada aumento de pressão, foi realizada uma pausa inspiratória de 4 segundos para realização da imagem tomográfica; dados de mecânica respiratória e gasometria arterial. A pressão inspiratória de 5cmH2O apresentou menores áreas hiperinsufladas (4,68±4,7%) e maiores áreas normoaredas (83,6%±6,24%) em comparação aos outros momentos de subida. A pressão de 5cmH2O demostrou ser a ventilação mais protetora para felinos com pulmão íntegro, pois apresentou a maior área normoaerada com boa oxigenação apesar de apresentar acidemia por acidose respiratória. Fato este que pode ser controlado aumentando a freqüência respiratória e/ou diminuindo o tempo inspiratório / Mechanical ventilation is crucial to blood oxygenation and carbon dioxide removal during sedation or general anesthesia. However, lung structure alterations may occur during anesthesia induction period, characterized by emergence of end-expiration collapse and alveolar overinsuflation zones during the inspiratory period, leading to lung injury associated to mechanical ventilation. Since there is no consensus on the best strategy to intraoperative mechanical ventilation in small animals undergoing surgery and general anesthesia, the aim of this study was to evaluate pulmonary hyperinflation at different pressure levels in the airways by computed tomography in cats undergoing general anesthesia. There were used 17 male adult cats undergoing controlled pressure mechanical ventilation, starting at a peak pressure of 5 cmH2O at \"ZEEP\", rising steeply 2 cmH2O every 5 minutes until reaching 15 cmH2O and then descending steeply each 2 cmH2O 5 minutes until it reached 5 cmH2O. The respiratory rate was maintained at 15 movements per minute and inspiratory time on 1 second, regardless of EtCO2. Immediately each pressure increase, it was performed an inspiratory pause of 4 seconds to perform the tomographic image, collect respiratory mechanic\'s data and arterial blood gases. inspiratory pressure 5cmH2O had shown lower hyperinflated areas (4,68±4,7%) and larger normoaerated areas (83,6%±6,24%) compared to other times of ascension. The pressure of 5cmH2O demonstrated to be the most protective ventilation for cats with intact lung, because it showed the largest normoaerated area with good oxygenation despite presenting acidemia by respiratory acidosis. This fact can be controlled by increasing or decreasing respiratory rate and inspiratory time