Bronchial artery

In response to the longitudinal stress, the bronchial arteries sometimes develop a characteristic layer of longitudinally oriented smooth muscle (Preto Parvis 1954). The smooth muscle cells in this layer were often separated by elastic fibrils. The lamina elastica interna is thin or even lacking. The bronchial arterioles are typical of the systemic vasculature with a thick media of circular myocytes. 

Bronchopulmonary anastomoses were described in the human lung (Verloop 1948) and in the lungs of rabbits, guinea-pigs, rats and mice (Verloop 1949). 

Constriction of the bronchial veins by norepinephrine leads to a shift of venous blood to the bronchopulmonary anastomoses, thus increasing venous admixture in the systemic arterial blood. With parenteral injection of epinephrine or isopre-naUne in asthmatics, a reduction in oxygen content of the blood occurs (Aviado and Micozzi 1981). 

The role of the tracheobronchial circulation in aerosol clearance has been discussed by Wagner (1995). Its supportive role for ciliated cells and mucus glands has not been studied. For this reason it is unclear whether this circulation plays a significant part in maintaining mucociliary clearance. Consequently, the capacity of the airway circulation to influence the clearance of soluble and insoluble particles remains ill-defined and requires investigation at a fundamental level. 

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The airways receive their blood supply from the systemic circulation via laryngeal, tracheal and bronchial arteries. In the trachea and large bronchi of humans and other large mammals, branches of arterioles deep in the airway wall supply the airway mucosa. In some peripheral airways, mucosal vessels may be supplied by the pulmonary circulation through vascular anastomoses. The airway mucosa has a rich blood supply, with a p>articularly extensive vascular network located immediately beneath the epithelium. Mucosal capillaries are tributaries of an extensive system of venules. In humans, a superficial plexus of venules connects with another plexus of venules located deeper in the mucosa. 

Cudkowicz, L. (1979). Bronchial arterial circulation in man. In Pulmonary Vascular Diseases (ed. K.M. Moser), pp. 111-232. Marcel Dekker, New York. 

Fig. 4. The vascular systems of the lung one originating from the pulmonary artery and supplying the alveolar spaces of the lung and the second originating from the bronchial arteries and supplying the central airways and respiratory bronchioles.

The dual blood supply to the lungs is from the pulmonary artery and the bronchial arteries. 

III. I. Expedlorants are fuppofed to increafe the fecretion of mucus in the branches of the windpipe, or to increafe the perfpiration of the lungs fecreted at the terminations of the bronchial artery. 

We found that the NO-releasing agent isosorbide dinitrate (ISDN, Nitrol ) enhanced antitumor activity of SMANCS/Lipiodol when they were infused into the tumor-feeding bronchial artery of lung cancer using a catheter preceding to the infusion of SMANCS arterially. This ISDN infusion enhanced... 

There is also a high-pressure systemic blood delivery system to the bronchi that is completely independent of the pulmonary low-pressure ( 3330 N/m ) circulation in healthy individuals. In diseased states, however, bronchial arteries are reported to enlarge when pulmonary blood flow is reduced, and some arteriovenous shunts become prominent [West, 1977]. 

Mai H, Rullon RMellot F,et al. (1999) Immediate and longterm results of bronchial artery embolization for life-threatening hemoptysis [see comment]. Chest 115 996-1001... 

IS.Uflacker R, Kaemmerer A, Picon PD, et al. (1985) Bronchial artery embolization in the management of hemoptysis technical aspects and long-term results. Radiology 157 637-644... 

Tomashefski JF, Cohen AM, Doershuk CF (1988) Longterm histopathologic follow-up of bronchial arteries after therapeutic embolization with polyvinyl alcohol (Ivalon) in patients with cystic fibrosis. Hum Pathol 19 555-561... 

Yoon W (2004) Embolic agents used for bronchial artery embolization in massive haemoptysis. Expert Opin Phar-macother 5 361-367... 

Bronchial artery embolization was first described in the literature in the 1970s by Remy [1], and over time it has become a well established treatment for patients with (massive) hemoptysis [2-5]. Technical improvements in both catheters and embolizing agents have attributed to the increase of the safety of the procedure and it s applicability. 

In this chapter the pathophysiology and etiology of hemoptysis will be discussed, as well as the diagnostic work-up of patients suffering from severe bronchial bleeding. Anatomy of bronchial arterial supply will be described. The techniques, pitfalls, complications and results of bronchial artery embolization will be discussed. 

Fig. 16.1. Curved multi-planar reconstruction of CT of the thoracic aorta, clearly demonstrating the origin arrowhead) and bifurcation into intercostal branches and bronchial artery arrow) of right inter-costobronchial trunk...

At fluoroscopy in the AP-projection, the vast majority of the bronchial arteries have their origin at the level where the left main stem bronchus over-lies the aorta, slightly below the level of the tracheal Carina (Fig. 16.3) [19,24). 

Four classical bronchial artery patterns have been identified [8] ... 

Type I two bronchial arteries on the left, and one on the right (intercostobronchial trunk) present in 40% of cases. 

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