Biomedical subjects

Paula Carvalho

Publications and source records attributed to Paula Carvalho.

2 recordsLinked to original sources

PubMed2006

Functional anatomy of bronchial veins.

The amount of bronchial arterial blood that drains into the systemic venous system is not known. Therefore, in this study we further delineated the functional anatomy of the bronchial venous system in six adult, anesthetized, and mechanically ventilated sheep. Through a left thoracotomy, the left azygos vein was dissected and the insertion of the bronchial vein into the azygos vein was identified. A pouch was created by ligating the azygos vein on either side of the insertion of the bronchial vein. A catheter was inserted into this pouch for the measurement of bronchial venous occlusion pressure and bronchial venous blood flow. An ultrasonic flow probe was placed around the common bronchial branch of the bronchoesophageal artery to monitor the bronchial arterial blood flow. Catheters were also placed into the carotid artery and the pulmonary artery. The mean bronchial blood flow was 20.6+/-4.2mlmin(-1) (mean+/-SEM) and, of this, only about 13% of the blood flow drained into the azygos vein. The mean systemic artery pressure was 72.4+/-4.1mmHg whereas the mean bronchial venous occlusion pressure was 38.1+/-2.1mmHg. The mean values for blood gas analysis were as follows: bronchial venous blood pH=7.54+/-0.02, PCO(2)=35+/-2.6, PO(2)=95+/-5.7mmHg; systemic venous blood-pH=7.43+/-0.02, PCO(2)=48+/-3.2, PO(2)=42+/-2.0mmHg; systemic arterial blood-pH=7.51+/-0.03, PCO(2)=39+/-2.1, PO(2)=169+/-9.8mmHg. We conclude that the major portion of the bronchial arterial blood flow normally drains into the pulmonary circulation and only about 13% drains into the bronchial venous system. In addition, the oxygen content of the bronchial venous blood is similar to that in the systemic arterial blood.

Animals↗

PubMed2006

Bronchial arterial imaging using helical computed tomography.

The bronchial arteries, which provide the systemic arterial supply to the lungs, are involved in a variety of disease processes in humans, including congenital disorders, infection, and pulmonary thromboembolism. In these conditions, the bronchial arteries hypertrophy and bronchial blood flow increases. Consequently, in many disorders, such as bronchiectasis, the bronchial arteries are a frequent source of haemoptysis, which may be massive and life-threatening. Evaluation of the bronchial circulation has typically required invasive imaging with angiography to determine the location of bleeding. Non-invasive assessment of bronchial arterial anatomy and morphology is currently being investigated with the use of helical computed tomography (CT). We evaluated eight patients with various lung diseases with helical CT (GE Medical Systems, LS16, Milwaukee, WI) to determine the imaging features of the bronchial circulation. Non-ionic contrast medium (iopromide) was injected intravenously (80-1000ml/30s) and scanning was triggered once contrast material was present in the pulmonary artery (average delay=15s) or ascending aorta (average delay=20s). Detector collimation (16-row unit) was 10mm. Imaging parameters included a section thickness of 0.6mm, kilovolt peak of 120, 150-440mA, pitch factor of 1.375, matrix of 512x512, and tube rotation time of 0.8s. The images were reconstructed and scanned isotropically (Advantage Workstation 4.1,GE Medical Systems). We conclude that helical computed tomography may provide a non-invasive means of evaluating the bronchial arteries and their role in pulmonary disease processes.

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