Bronchial artery perfusion scintigraphy to assess bronchial artery blood flow after lung transplantation.
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The bronchial arterial system is inevitably interrupted in transplanted lungs when removing the organs from the donor, but it can be reestablished by direct bronchial artery revascularization (BAR) during implantation. The purpose of this study was to visualize and quantify the distribution of bronchial artery perfusion after en bloc double lung transplantation with BAR, by injecting radiolabeled macroaggregated albumin directly into the bronchial artery system. METHODS: BAR was performed using the internal mammary artery as conduit. Patients were imaged 1 mo (n = 13) or 2 y (n = 9) after en bloc double lung transplantation with BAR. Immediately after bronchial arteriography, 100 MBq macroaggregated albumin (45,000 particles) were injected through the arteriographic catheter. Gamma camera studies were then acquired in the anterior position. At the end of imaging, with the patient remaining in exactly the same position, 81mKr-ventilation scintigraphy or conventional intravenous pulmonary perfusion scintigraphy or both were performed. Images were evaluated by visual analysis, and a semiquantitative assessment of the bronchial arterial supply to the peripheral parts of the lungs was obtained with conventional pulmonary scintigraphy. RESULTS: The bronchial artery scintigraphic images showed that the major part of the bronchial arterial flow supplied central thoracic structures, but bronchial artery perfusion could also be demonstrated in the peripheral parts of the lungs when compared with conventional pulmonary scintigraphy. There were no differences between scintigrams obtained from patients studied 1 mo and 2 y post-transplantation. CONCLUSION: Total distribution of bronchial artery supply to the human lung has been visualized in lung transplant patients. This study demonstrates that this nutritive flow reaches even the most peripheral parts of the lungs and is present 1 mo as well as 2 y after lung transplantation. The results suggest that bronchial artery revascularization may be of significance for the long-term status of the lung transplant. (+info)
Audit of bronchial artery embolisation in a specialist respiratory centre.
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OBJECTIVE: To audit the use of bronchial arteriography and embolisation for controlling haemoptysis. DESIGN: Retrospective review of radiological and clinical data. SETTING: Brompton and National Heart Hospitals. PATIENTS: 35 patients with severe pulmonary disease in whom 58 bronchial arteriograms were obtained between 1 January 1984 and 31 December 1989 with the intention of bronchial artery embolisation for controlling haemoptysis. MAIN MEASURES: Rate of technical success and cessation of haemoptysis; detailed evaluation of patients, particularly those with major haemoptysis (> 100 ml expectorated blood); and retrospective assessment of the appropriateness of the procedure in each. RESULTS: 58 procedures were performed, nine of which were unsuitable for detailed analysis. Nine procedures were for minor haemoptysis, which subsequently recurred, and 40 for recent major haemoptysis in 26 patients with cystic fibrosis (16) aspergilloma (six), bronchiectasis (three), and an unknown diagnosis (one). The median total volume of haemoptysis in the episode before the procedure was 680 ml (range 270-2200 ml). Embolisation was technically successful in 33/40 procedures, in 17 of which, however, major haemoptysis recurred within 10 days of the procedure, leaving 16 clinically and technically successful procedures in 15 patients. Five patients (three with aspergilloma, two with cystic fibrosis) died of haemoptysis despite attempted embolisation. CONCLUSION: Success rate of bronchial artery embolisation was 40%(16/40). IMPLICATIONS: Bronchial artery embolisation is probably not justified for minor haemoptysis or when performed more than one week after a major haemoptysis. Repeat arteriograms during a single period of haemoptysis are seldom useful. With these criteria 43% fewer procedures would have been performed with no loss of clinical benefit. (+info)
The functional anatomy of the bronchial circulation of the domestic fowl.
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The bronchial circulation was studied in 25 adult domestic fowls. The right and left bronchial arteries originated caudal to the syrinx from a bronchoesophageal artery which is a branch of the right common carotid artery. Each bronchial artery ramified on the wall of the extrapulmonary part of the corresponding primary bronchus and finally anastomosed directly with a branch of the pulmonary artery at the hilus of the lung. Thr bronchial artery did not accompany the intrapulmonary part of the primary bronchus. The branches of each bronchial artery formed an anastomosing network on the wall of the extrapulmonary part of the primary bronchus. The calibre of the bronchial artery at its anastomosis with the branch of the pulmonary artery was greater than at its origin from the bronchoesophageal artery. Intravenous injections of Lycopodium spores indicated that the blood flows from the pulmonary artery into the bronchial artery. Small bronchial veins drained the extrapulmonary part of the primary bronchus into the pulmonary vein and the oesophageal veins. The intrapulmonary part of the primary bronchus was supplied by branches of the pulmonary artery and drained by tributaries of the pulmonary vein. The blood supply to the primary bronchus could constitute a shunt capable of passing blood from the pulmonary artery into the pulmonary vein without going through the exchange tissue. The parabronchial (atrial) muscles received a blood supply directly from the exchange tissue via septal venules which formed a network underneath the muscle bundles, without actually penetrating between the muscle cells. These venules drained into atrial veins which were tributaries of the pulmonary vein. The atrial muscles probably also received oxygen by direct diffusion from the parabronchial lumen. The pleura was supplied by the oesophageal branches of the bronchoesophageal artery, and by small twigs from the internal thoracic and intercostal arteries. (+info)
Altered contractile sensitivity of isolated bronchial artery to phenylephrine in ovalbumin-sensitized rabbits.
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We tested the hypothesis that atopy and/or allergic lung inflammation enhances alpha1-adrenoceptor-mediated contractions of the bronchial artery. Bronchial arterial resistance vessels were isolated from rabbits that had undergone either systemic ovalbumin (OVA) sensitization followed by saline aerosol challenge (OVA/saline rabbits), or OVA sensitization followed by OVA aerosol challenge (OVA/OVA rabbits), or no sensitization followed by saline aerosol challenge (control rabbits). In OVA/OVA rabbits, bronchoalveolar lavage and lung histology revealed lymphocytic and eosinophilic inflammation. Arterial rings were contracted with phenylephrine (PE). In endothelium-intact arteries isolated from OVA/saline and OVA/OVA rabbits, PE responsiveness was enhanced compared with that of arteries isolated from controls. The nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester increased the contractile response to PE in all three experimental groups to a similar degree, suggesting that depressed NOS activity was not involved in the enhanced PE responsiveness in OVA/saline and OVA/OVA rabbits. After endothelium removal, arteries from OVA/saline and control rabbits showed similar PE responsiveness, indicating that the enhancement of PE responsiveness was endothelium dependent, possibly due to an endothelial constricting factor. In OVA/OVA rabbits, endothelium-denuded arteries showed decreased PE responsiveness compared with the other two groups; this difference was abolished by NG-nitro-L-arginine methyl ester. We conclude that systemic sensitization with OVA per se enhances PE-induced contractions of isolated bronchial arteries in rabbits by an endothelium-dependent mechanism and that allergic lung inflammation attenuates this effect by increased nonendothelial NOS activity. (+info)
The porcine bronchial artery: surgical and angiographic anatomy.
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The pig is often used in experimental studies on the significance of bronchial artery circulation, but the anatomy of this artery is only poorly described. The purpose of this study was to improve the anatomical basis for experimental studies on the porcine bronchial artery circulation. The origin of the artery from the aorta is described in 32 pigs. Heart-lung blocks were perfused with saline and removed in 16 pigs, and the broncho-oesophageal orifice was identified and cannulated. In these 16 specimens the intrapulmonary ramification was studied by angiography, and the extrapulmonary distribution and supply area by injection of Evans Blue. The broncho-oesophageal artery originated from the aorta as a single trunk in 91%. Angiography showed that each principal bronchus was accompanied by 2 bronchial artery branches far into the lung parenchyma. The central branching pattern of the artery between the aorta and the principal bronchi was divided into 3 subtypes. Evans Blue showed communication with the whole mediastinum. The anatomical relations are described. It is concluded that the broncho-oesophageal artery divides to follow each bronchus with 2 bronchial branches. A nomenclature for these branches is suggested. The pig anatomy is suited for experimental investigations on the bronchial circulation. (+info)
The porcine bronchial artery. Anastomoses with oesophageal, coronary and intercostal arteries.
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Information about the existence and anatomy of arterial anastomoses with the porcine bronchial artery is lacking in the literature. Prior to basic physiological investigations in a porcine model related to lung transplantation with bronchial artery revascularisation, this study was designed to examine the anatomy of systemic arterial anastomoses with the bronchial artery system. Twenty pigs were studied in 3 groups. In 2 groups the heart-lung block was removed with all mediastinal structures. One group served for investigation of coronary-bronchial artery anastomoses and one for investigation of oesophageal-bronchial artery anastomoses. The systemic arteries to be examined were cannulated. The inflated heart-lung block was examined macroscopically with Evans blue, and radiographically after contrast injection. In the 3rd group intercostobronchial artery anastomoses were studied radiographically with the heart-lung block in situ. Coronary-bronchial artery anastomoses were demonstrated in 3 of the 5 pigs with an aortic 'pouch' technique, but contrast was very limited in 2 of these 3. Oesophageal arterial anastomoses with bronchial arterial branches and/or the pulmonary veins were demonstrated in 6 of the 7 pigs and more markedly than the coronary-bronchial anastomoses. Intercostobronchial artery anastomoses could not be demonstrated angiographically. It was concluded that the existence of coronary-bronchial and oesophageal-bronchial artery anastomoses in the pig appear to establish an arterial net between the base of the heart and the distal oesophagus. The resemblance to human oesophageal-bronchial artery anastomoses supports use of a porcine model for experimental studies. (+info)
Human bronchial artery blood flow after lung Tx with direct bronchial artery revascularization.
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The inaccuracy of measuring human bronchial artery blood flow has previously been considerable. En bloc double-lung transplantation with bronchial artery revascularization (BAR) using a single conduit offers the unique opportunity of direct measurement of the total bronchial artery blood flow. In eight en bloc double-lung-transplanted patients with complete BAR, the basal blood flow was measured by using a 0.014-in. Doppler guide wire and arteriography. The average peak velocity in the conduit was 12-73 cm/s [+/-2.1 (SD) cm/s], and the conduit diameter was 1.7-3.1 mm [+/-0.10 (SD) mm], giving individual basal flow values between 19 and 67 ml/min [+/-5 (SD) ml/min], or 0.2-1.9% of estimated cardiac output. In three patients basal measurements were followed by injection of nitroglycerin and verapamil into the conduit. This increased the bronchial artery flow to 121-262% of basal values (31-89 ml/min). The measured values appear more physiologically plausible than previous bronchial artery blood flow measurements in humans. (+info)
Bronchial vasodilation evoked by increased lower airway osmolarity in dogs.
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Hyperosmotic saline solutions stimulate lower airway sensory nerves. To determine whether airway hyperosmolarity evokes neurally mediated changes in bronchial artery blood flow (Qbr), we measured the effect of injection of small volumes (1 ml) of hyperosmotic saline into a right lobar bronchus on Qbr of anesthetized, artificially ventilated dogs. In 14 dogs, hyperosmotic saline (1,200 and 2,400 mmol/l) increased Qbr by 58 +/- 12 (SE) and 118 +/- 12%, respectively, from a baseline of 8 +/- 2 ml/min. Qbr increased within 6-8 s of the injections, peaked at 20 s, and returned to control over 2-3 min. Isosmotic saline had minimal effects. In contrast, hyperosmotic saline decreased flow in an intercostal artery that did not supply the airways. The bronchial vasodilation was decreased by 72 +/- 11% after combined blockade of alpha-adrenoceptors and muscarinic cholinergic receptors and by 66 +/- 6% when the cervical vagus nerves were cooled to 0 degrees C. Blockade of H(1) and H(2) histamine receptors did not reduce the nonvagal response. We conclude that hyperosmolarity of the lower airways evokes bronchial vasodilation by both a centrally mediated reflex that includes cholinergic and adrenergic efferent pathways and by unidentified local mechanisms. (+info)