2Trachea, Bronchi and Lungs Benish IslamCoordinator Lecturer Surgical (IPMs) kmu
3Trachea Mobile cartilaginous, membranous tube. Begins at neck, lower border of cricoid cartilage.(at level of 6th cervical vertebra)In thorax trachea ends at Carina by dividing into principle (main) bronchi.(Level of sternal angle, 4th 5th thoracic vertebra)
4Cont. Right: azygous vein,rt. Vagus nerve, pleura In adults:4 ½ inch long1 inch diameter.U shped bars (rings) of hyaline crtilage embedded in wall.Anterior: sternum,thymus,lt. bracheocephalic vein,lt. bcommon caroti arteries,arch of aortaPosterior: esophagus, lt recurrent laryngeal nerveRight: azygous vein,rt. Vagus nerve, pleuraLeft: arch of aorta, lt subclavian, lt common carotid,phrenic nerves, pleura.Arterial supply:upper 2/3 inf. Thyroid arteriesLower 1/3 bronchial arteriesLymph nodes:pre tracheal,para tracheal,deep cervical nodes.Nerve Supply: sessory supply from vagi and recurrent laryngeal nerves.
5BronchiTrachea bifurcates into rt. and lt. principal (primary) bronchi.Rt. Principal bronchi is wider shorter, vertical 1inch.Before entering hilum gives superior lobar bronchus.On entering hilum it divides into: Middle, inferior lobar bronchusLeft principal bronchi: narrow, longer, more horizontal, 2 inchOn entering hilum divides into:Superior, inferior lobar bronchus
8Lungs Apex: projects upward into neck 1 inch above clavicle. Costal surface: convexMediastinal surface:concave,molds to pericardiumHilum: bronchi vessels and nerves form root,enter and leave lung.Anterior border is thin,overlaps heartCardiac notch on lt. lung.
14Blood Supply Arterial supply: bronchial artery Bronchi, lung, pleuraAlveoliArterial supply: bronchial artery(Branches of descending aorta)Bronchial veins-communicates with pulmonary veins (drains into hemizygos Azygos veins)Alveoli receives deoxygenated blood from branches of pulmonary arteries.Oxygenated blood drains into tributaries of pulmonary veins.
15Lymphatic supplySuperficial plexus drains to broncho pulmonary nodes at hilum.Deep plexus travels along bronchi, pass through pulmonary nodes.All lymph from lungs drains to tracheobronchial nodes and then to bronchomediastinal lymph trunk.
16Nerve supply Pulmonary plexus Sympathetic trunk + Para sympathetic fibers from vagus nerveSympathetic efferent fibers cause bronchodilation and vasoconstrictionParasympathetic efferent fibers: bronchoconstrition,vasodilation, inc.glandular secretion,Afferent impulse from both sympathtic and parasym.Derives from stretch receptors in alveoli walls to central nervous system.