Impacto de biópsia pulmonar a céu aberto na insuficiência respiratória aguda refratária / Impact of open lung biopsy on refractory acute respiratory failure

OBJETIVO: Verificar o impacto dos resultados da biópsia pulmonar a céu aberto nas decisões que determinem mudanças nas estratégias de tratamento de pacientes críticos, com infiltrados pulmonares difusos e insuficiência respiratória aguda refratária, bem como na melhora de seu quadro clínico. MÉTODOS: Foram avaliados 12 pacientes com insuficiência respiratória aguda e sob ventilação mecânica, que foram submetidos à biópsia pulmonar a céu aberto (por toracotomia) após a ausência de resposta clínica ao tratamento padrão. RESULTADOS: A maior causa isolada de insuficiência respiratória aguda foi a infecção viral, identificada em 5 pacientes (40 por cento). A avaliação pré-operatória da causa da insuficiência respiratória foi modificada em 11 pacientes (91,6 por cento), e um diagnóstico específico foi feito em 100 por cento dos casos. A taxa de mortalidade foi de 50 por cento, a despeito das mudanças no regime terapêutico. Seis pacientes (50 por cento) sobreviveram e obtiveram alta hospitalar. Todos os pacientes que obtiveram alta sobreviveram por pelo menos um ano após a biópsia pulmonar a céu aberto, totalizando uma taxa de sobrevida em um ano de 50 por cento dentre os 12 pacientes estudados. Quanto aos pacientes que faleceram no hospital, o tempo de sobrevida após a biópsia pulmonar a céu aberto foi de 14 + 10,8 dias. CONCLUSÃO: Concluímos que a biópsia pulmonar a céu aberto é uma ferramenta útil no controle da insuficiência respiratória aguda quando não se observa melhora clínica após o tratamento padrão, já que pode resultar em um diagnóstico específico que requeira tratamento distinto, provavelmente diminuindo a taxa de mortalidade desses pacientes.

OBJECTIVE: To determine the impact that open lung biopsy findings have on decisions regarding changes in the treatment strategies employed for critically ill patients presenting diffuse pulmonary infiltrates and suffering from refractory acute respiratory failure, as well as on their clinical improvement. METHODS: This study involved 12 mechanically ventilated patients with acute respiratory failure who were subjected to open lung biopsy (by thoracotomy) after not presenting a clinical response to standard treatment. RESULTS: The single most common cause of the acute respiratory failure was viral infection, which was identified in 5 patients (40 percent). The pre-operative evaluation of the cause of respiratory failure was modified in 11 patients (91.6 percent), and a specific diagnosis was made in 100 percent of the cases. Regardless of changes in treatment regimen, the mortality rate was 50 percent. Six patients (50 percent) survived to be discharged from the hospital. All of the discharged patients survived for at least one year after the open lung biopsy, for an overall one-year survival rate of 50 percent among the 12 patients studied. For the patients who died in the hospital, the time of survival after open lung biopsy was 14 + 10.8 days. CONCLUSION: We conclude that open lung biopsy is a useful tool in the management of acute respiratory failure when there is no clinical improvement after standard treatment, since it can lead to a specific diagnosis that requires distinct treatment, which probably lowers the mortality rate among such patients.

Impact of open lung biopsy on refractory acute respiratory failure.

OBJECTIVE: To determine the impact that open lung biopsy findings have on decisions regarding changes in the treatment strategies employed for critically ill patients presenting diffuse pulmonary infiltrates and suffering from refractory acute respiratory failure, as well as on their clinical improvement. METHODS: This study involved 12 mechanically ventilated patients with acute respiratory failure who were subjected to open lung biopsy (by thoracotomy) after not presenting a clinical response to standard treatment. RESULTS: The single most common cause of the acute respiratory failure was viral infection, which was identified in 5 patients (40%). The pre-operative evaluation of the cause of respiratory failure was modified in 11 patients (91.6%), and a specific diagnosis was made in 100% of the cases. Regardless of changes in treatment regimen, the mortality rate was 50%. Six patients (50%) survived to be discharged from the hospital. All of the discharged patients survived for at least one year after the open lung biopsy, for an overall one-year survival rate of 50% among the 12 patients studied. For the patients who died in the hospital, the time of survival after open lung biopsy was 14 + 10.8 days. CONCLUSION: We conclude that open lung biopsy is a useful tool in the management of acute respiratory failure when there is no clinical improvement after standard treatment, since it can lead to a specific diagnosis that requires distinct treatment, which probably lowers the mortality rate among such patients.

Ventilator associated pneumonia: comparison between quantitative and qualitative cultures of tracheal aspirates.

INTRODUCTION: Deferred or inappropriate antibiotic treatment in ventilator-associated pneumonia (VAP) is associated with increased mortality, and clinical and radiological criteria are frequently employed to establish an early diagnosis. Culture results are used to confirm the clinical diagnosis and to adjust or sometimes withdraw antibiotic treatment. Tracheal aspirates have been shown to be useful for these purposes. Nonetheless, little is known about the usefulness of quantitative findings in tracheal secretions for diagnosing VAP. METHODS: To determine the value of quantification of bacterial colonies in tracheal aspirates for diagnosing VAP, we conducted a prospective follow-up study of 106 intensive care unit patients who were under ventilatory support. In total, the findings from 219 sequential weekly evaluations for VAP were examined. Clinical and radiological parameters were recorded and evaluated by three independent experts; a diagnosis of VAP required the agreement of at least two of the three experts. At the same time, cultures of tracheal aspirates were analyzed qualitatively and quantitatively (10(5) colony-forming units [cfu]/ml and 10(6) cfu/ml) RESULTS: Quantitative cultures of tracheal aspirates (10(5) cfu/ml and 10(6) cfu/ml) exhibited increased specificity (48% and 78%, respectively) over qualitative cultures (23%), but decreased sensitivity (26% and 65%, respectively) as compared with the qualitative findings (81%). Quantification did not improve the ability to predict a diagnosis of VAP. CONCLUSION: Quantitative cultures of tracheal aspirates in selected critically ill patients have decreased sensitivity when compared with qualitative results, and they should not replace the latter to confirm a clinical diagnosis of VAP or to adjust antimicrobial therapy.

Acute remodeling of parenchyma in pulmonary and extrapulmonary ARDS. An autopsy study of collagen-elastic system fibers.

This study aimed at evaluating acute pulmonary remodeling, focusing on alterations of fibers of the collagenous and elastic systems in ARDS in the exudative phase according to the etiology of the disease. ARDS patients (n = 23), who died in our institution between 1989 and 1997, were retrospectively studied. Ten patients who died in accidents, without any pathological changes in the lung, and ten patients with Congestive Heart Failure (CHF), submitted to mechanical ventilation, were used as control groups. Histological slides were sampled from the autopsied lungs and stained by the Picrosirius and Weigert's resorcin-fuchsin methods. The fiber content of the collagenous and elastic systems of the alveolar septum was measured by image analysis. All patients were in the early ARDS phase (n = 23), 10 pulmonary and 13 extra-pulmonary diseases. Collagen content was greater in pulmonary (1.23+/-0.27) than in extra-pulmonary (0.92+/-0.39) ARDS in the early phase of the disease (p = 0.05). No differences were observed concerning the elastic fibers' content. Extracellular matrix (ECM) remodeling occurs early in the development of acute lung injury and appears to depend on the site of initial insult (pulmonary or extrapulmonary). The present study provides the basis for a prospective, controlled investigation.