Effect of bronchial artery blood flow on cardiopulmonary bypass-induced lung injury.
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Cardiovascular surgery requiring cardiopulmonary bypass (CPB) is frequently complicated by postoperative lung injury. Bronchial artery (BA) blood flow has been hypothesized to attenuate this injury. The purpose of the present study was to determine the effect of BA blood flow on CPB-induced lung injury in anesthetized pigs. In eight pigs (BA ligated) the BA was ligated, whereas in six pigs (BA patent) the BA was identified but left intact. Warm (37 degrees C) CPB was then performed in all pigs with complete occlusion of the pulmonary artery and deflated lungs to maximize lung injury. BA ligation significantly exacerbated nearly all aspects of pulmonary function beginning at 5 min post-CPB. At 25 min, BA-ligated pigs had a lower arterial Po(2) at a fraction of inspired oxygen of 1.0 (52 +/- 5 vs. 312 +/- 58 mmHg) and greater peak tracheal pressure (39 +/- 6 vs. 15 +/- 4 mmHg), pulmonary vascular resistance (11 +/- 1 vs. 6 +/- 1 mmHg x l(-1) x min), plasma TNF-alpha (1.2 +/- 0.60 vs. 0.59 +/- 0.092 ng/ml), extravascular lung water (11.7 +/- 1.2 vs. 7.7 +/- 0.5 ml/g blood-free dry weight), and pulmonary vascular protein permeability, as assessed by a decreased reflection coefficient for albumin (sigma(alb); 0.53 +/- 0.1 vs. 0.82 +/- 0.05). There was a negative correlation (R = 0.95, P < 0.001) between sigma(alb) and the 25-min plasma TNF-alpha concentration. These results suggest that a severe decrease in BA blood flow during and after warm CPB causes increased pulmonary vascular permeability, edema formation, cytokine production, and severe arterial hypoxemia secondary to intrapulmonary shunt. (+info)
Giant mediastinal bronchial artery aneurysm mimicking benign esophageal tumor: a case report and review of 26 cases from literature.
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Mediastinal bronchial artery aneurysm is rare but potentially life-threatening, and requires prompt treatment to avert rupture with catastrophic results. A 78-year-old man was referred to our hospital with a benign esophageal tumor, which appeared as an extrinsic, extramucosal filling defect on an esophagogram. Chest computed tomography and selective bronchial arteriography led to a definitive diagnosis of mediastinal bronchial artery aneurysm. Aneurysmectomy and closure of the ostia of both the afferent and efferent bronchial arteries was performed via standard posterolateral thoracotomy. Postoperative course was uneventful, and the patient was discharged on the seventh postoperative day. (+info)
Color Doppler sonographic mapping of pulmonary lesions: evidence of dual arterial supply by spectral analysis.
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OBJECTIVE: Within pulmonary lesions, flow signals of pulmonary arteries can be discriminated from flow signals of central bronchial and peripheral bronchial arteries on color Doppler sonography. Our aim was to evaluate the evidence and frequency of different arterial supplies of pleural-based pulmonary lesions using qualitative and quantitative color Doppler sonography. METHODS: Forty-one patients with roentgenologically confirmed pleural-based pulmonary lesions were investigated by color Doppler sonography. The following parameters were investigated: (1) qualitative color Doppler sonographic evidence of vascularization, (2) quantitative color Doppler sonographic evidence of arterial flow signals (resistive index and pulsatility index), and (3) number of different arterial flow signals in 1 lesion by color Doppler sonographic mapping. RESULTS: We found no vascularization in 5 patients, sparse vascularization in 21, and pronounced vascularization in 15. Quantitative color Doppler sonographic parameters were as follows: mean pulmonary artery resistive index, 1.2; mean central bronchial artery resistive index, 0.5; mean peripheral bronchial artery resistive index, 0.7; mean pulmonary artery pulsatility index, 7.8; mean central bronchial artery pulsatility index, 0.7; and mean peripheral bronchial artery pulsatility index, 1.6. There was a significant difference between all types of flow signals for resistive and pulsatility index values but not between pulmonary and peripheral bronchial arteries (P = .068). In 41 patients, 57 different arterial flow signals were determined; 19 (46%) of these patients had 2 or more different arterial flow signals in a lesion. There was no significant difference between benign and malignant lesions regarding the number of flow signals. CONCLUSIONS: Evidence of at least a dual arterial supply can be found on quantitative color Doppler sonography in almost 50% of pulmonary lesions. A single spectral analysis is not suitable for characterization of the arterial supply of pulmonary lesions. (+info)
Soluble gas exchange in the pulmonary airways of sheep.
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We studied the airway gas exchange properties of five inert gases with different blood solubilities in the lungs of anesthetized sheep. Animals were ventilated through a bifurcated endobronchial tube to allow independent ventilation and collection of exhaled gases from each lung. An aortic pouch at the origin of the bronchial artery was created to control perfusion and enable infusion of a solution of inert gases into the bronchial circulation. Occlusion of the left pulmonary artery prevented pulmonary perfusion of that lung so that gas exchange occurred predominantly via the bronchial circulation. Excretion from the bronchial circulation (defined as the partial pressure of gas in exhaled gas divided by the partial pressure of gas in bronchial arterial blood) increased with increasing gas solubility (ranging from a mean of 4.2 x 10(-5) for SF6 to 4.8 x 10(-2) for ether) and increasing bronchial blood flow. Excretion was inversely affected by molecular weight (MW), demonstrating a dependence on diffusion. Excretions of the higher MW gases, halothane (MW = 194) and SF6 (MW = 146), were depressed relative to excretion of the lower MW gases ethane, cyclopropane, and ether (MW = 30, 42, 74, respectively). All results were consistent with previous studies of gas exchange in the isolated in situ trachea. (+info)
Major haemoptysis in children with cystic fibrosis: a 20-year retrospective study.
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BACKGROUND: Major haemoptysis occurs in approximately 1% of children with cystic fibrosis (CF). This report describes management and follow-up of these children at a tertiary centre in Australia. METHODS: Retrospective review of medical records from 1980-1999. RESULTS: Fifty-one children (45% female) had major haemoptysis (102 episodes). Mean age at first episode was 15 years (range 7-19) and mean FEV(1) was 56% predicted (range 14-98). Massive life-threatening haemoptysis was not confined to those with severe lung disease (FEV1 < 50% predicted). Bronchial artery embolisation (BAE) was more likely to be the initial treatment for those with massive haemoptysis and chronic recurrent bleeding tended to be treated conservatively (P = 0.01). Overall, 52 BAE were performed in 28 children with an immediate success rate of 98%; 13 children (46%) had repeated BAE. Four patients died as a direct result of severe haemoptysis. Mean follow-up was 54 months (range 0.5-183). Median survival time (Kaplan-Meier estimate) after first haemoptysis was 70 months, with a significantly longer survival for male patients independent of age (RR 3.8; 95% CI 1.7-8.8; P = 0.001). Median survival time following initial treatment with BAE was longer (103 months) compared to conservative treatment (52 months, P = 0.09). CONCLUSIONS: Massive haemoptysis was unrelated to the severity of lung disease and was more likely to be treated with embolisation. BAE was highly effective, however, 46% of the children required re-embolisation at some time, which is similar to the recurrence risk for major hemoptysis treated conservatively on longer term follow-up. (+info)
Bronchial to subclavian shunt in a CF patient. A potential pitfall for embolization.
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Bronchial artery embolization is a well accepted and widely used technique in the management of massive haemoptysis in cystic fibrosis (CF). It can be a complex procedure requiring a deep knowledge of the bronchial artery anatomy including the possible bronchial anastomoses. We report a case of complex vascular anatomy of the left bronchial artery with multiple anastomoses with the ipsilateral subclavian artery as cause of non-attempted embolization. (+info)
Structure and size of bronchopulmonary anastomoses in sheep lung.
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The distribution and drainage of bronchial arterial blood flow are complex. We used two different methods to study the bronchial-pulmonary anastomoses in sheep lung. Initially, we injected two different sizes of fluorescent microspheres (15 and 100 microm diameter) into the bronchial artery and histologically determined where the different-size microspheres were entrapped in the lung. In a second series of animals, we injected Microfil into the bronchial artery to observe the anastomotic vessels. The microsphere data confirmed the existence of bronchial-to-pulmonary anastomoses. No microspheres were found in the systemic organs (heart and kidney), confirming the absence of large bronchial artery-to-pulmonary vein anastomoses. Unexpectedly, proportionately more large microspheres (100 microm) lodged in the alveolar parenchyma when compared to 15 microm microspheres. This suggests that there are many more small bronchial (< 100 microm) arterioles feeding the airway mucosa than the larger anastomotic vessels feeding into the parenchyma. In the Microfil cast lungs, we observed four types of anastomotic vessels: bronchial arteries/arterioles that anastomose with pulmonary arteries/arterioles that accompany airways; bronchial arterioles that anastomose directly with parenchymal (and eventually alveolar) vessels; bronchial arterioles that anastomose with blood vessels that do not accompany airways; and bronchial arterioles that anastomose with bronchial veins. Based on our in vivo microsphere data, the vessels that do not accompany the airways are most likely bronchial venules, not pulmonary venules. (+info)
Topographic anatomy of bronchial arteries in the pig: a corrosion cast study.
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The anatomy of porcine bronchial circulation has not been fully described. The purpose of this study was to investigate the extrapulmonary topographic anatomy of bronchial arteries in pig. Ten pigs weighing 15-25 kg were studied. Between one and four bronchial arteries were found in each pig. The bronchoesophageal artery (BEA), tracheobronchial artery (TBA), inferior bronchial artery (IBA) and accessory bronchial artery (ABA) were present in 10/10, 8/10, 6/10 and 2/10 animals, respectively. The trunk of BEA had a diameter of about 3 mm, a length of 1-7 mm, and originated from the anterior and medial aspect of the descending thoracic aorta at the level between the 2nd and 4th thoracic vertebrae (T2-T4) in all animals. The extrapulmonary topographic anatomy of bronchial arteries in pigs exhibits similarities to that of humans. BEA is the main blood supplier of the porcine tracheobronchial tree with a relatively constant location of origin and a sufficient size for anastomosis. These characteristics render BEA the ideal vessel for bronchial revascularization in pigs. (+info)