RESUMO
The biogenic amine, radioactive 5-hydroxytryptamine, is removed from the blood during passage through the pulmonary vasculature. After one hour of hemorrhagic shock, the extraction rate increased from 74 to 89 per cent. One and two hours after resuscitation, the lung extracted only 30 per cent of the 5-hydroxytryptamine. The relationship between the pathophysiologic state and altered amine removal is a reflection of prolonged exposure to receptor sites or increased diffusion of serotonin across the endothelium.
Assuntos
Pulmão/metabolismo , Serotonina/metabolismo , Choque Hemorrágico/metabolismo , Animais , Pressão Sanguínea , Radioisótopos de Carbono , Cães , Hemodinâmica , Pulmão/irrigação sanguíneaRESUMO
Pneumothorax occurs in approximately 25% of patients maintained on high levels of positive end-expiratory pressure. In several cases at our Institution, a sudden and rapid elevation in pulmonary artery pressure (PAP) monitored by use of the Swan-Ganz catheter accompanied the development of a pneumothorax. In the three cases described, the change in PAP was observed before a pneumothorax became otherwise clinically evident. Two of the three patients had marked restrictive lung disease associated with the adult respiratory distress syndrome and the third patient had large bilateral pleural effusions. It is postulated that the rise in PAP was related to a sudden decrease in the size of an already compromised pulmonary arterial vascular bed produced by hypoxic vasoconstriction and mechanical compression secondary to the pneumothorax. In the ICU, elevation of PAP may be a useful and early indicator of pulmonary barotrauma.
Assuntos
Pressão Sanguínea , Pneumotórax/diagnóstico , Artéria Pulmonar , Adulto , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumotórax/diagnóstico por imagem , Pneumotórax/etiologia , Respiração com Pressão Positiva/efeitos adversos , Radiografia , Síndrome do Desconforto Respiratório/terapiaRESUMO
The risk factor of pulmonary artery catheterization was assessed in 392 critically ill patients. Major indications for catheterization in the operating room were marginal cardiovascular reserve, anticipated large fluid and blood loss, and hypotensive anesthesia. Immediate complications included cardiac arrhythmia, carotid artery puncture, and pneumotherax. Long-term complications included positive bacterial cultures, pulmonary infarction and neuropathy. None of the complications were directly responsible for the deaths in this series. Pulmonary artery monitoring in critically ill persons is a relatively safe procedure.
