LUNGS AND BRONCHIAL TREE 2021.pdf

LUNGS AND BRONCHIAL TREE DR EID NADDAR ALI  Trachea:  10 cm tube  It lies in the midline, its upper 1/2 lies in the neck while its lower ½ is in thorax  Begins at the level of C6 (cricoid cartilage) as continuation of larynx  Ends in the th...

LUNGS AND BRONCHIAL TREE DR EID NADDAR ALI  Trachea:  10 cm tube  It lies in the midline, its upper 1/2 lies in the neck while its lower ½ is in thorax  Begins at the level of C6 (cricoid cartilage) as continuation of larynx  Ends in the thorax, at the level of sternal angle ( lower border of T4) by dividing into two main bronchi.  Structure : It consists of 16-20 C-shaped cartilages  transmits the air from the larynx to the lungs.  The 2 bronchi is separated from inside by the CARINA. CARINA  Tracheostomy  tracheostomy is a medical procedure — either temporary or permanent — that involves creating an opening in the neck in order to place a tube into the trachea  is performed in case of restricted airways making normal breathing impossible as cancer larynx.  Bronchial Tree The trachea divides into 23 generations before it becomes alveolar sac Main bronchi  Right bronchus Left bronchus Shorter , 2.5 cm ( one inch) Longer, 5 cm (2 inches) Wider Narrower Enters the lung opposite T5 Enters the lung opposite T6 More in line with trachea Less in line with trachea Foreign body usually enters the right Less to occur lung Divides into 3 lobar bronchi Divides into 2 lobar bronchi Upper, middle & lower Upper & lower  Secondary (lobar) Bronchi  Three in right lung, two in left lung.  Intrapulmonary bronchi  Each extend into a pulmonary lobe of the lung  Sometimes called lobar bronchi  Each secondary bronchi enters a lung lobe and divides to form tertiary bronchi Teriary bronchi (segmental)  10 in each side  Each tertiary bronchus supplies bronchopulmonary segment  Bronchioles  When tertiary bronchi lose their cartilage, they are called bronchioles which are microscopic  Diameter 5mm  Bronchioles make up 5th-16th generations  The bronchioles divide into respiratory bronchioles (17th -19th generations) that contain alveoli on their walls  Each respiratory bronchiole terminates in an alveolar duct ( 20th -22th generation) that open in alveolar sac (23th) and then the alveoli  The walls of the alveoli are one-cell thick and is covered by capillaries.  The alveoli are the functional unit of the lungs.  Conducting air ways Nose , larynx, trachea , main bronchi. Lobar bronchi, segmental bronchi Bronchioles down to terminal bronchioles Respiratory air ways Respiratory bronchioles Alveolar ducts , alveolar sacs and alveoli Lungs  apex - We have 2 lungs Lungs - Each lung has -apex, base ,surfaces and borders - apex above lies at the root of the neck - base below, concave related to diaphragm base Each lung is divided into lobes by fissures : Lobe fissure - 3 borders : anterior, posterior and inferior borders - The anterior border of the left lung has the lingula and cardiac notch cardiac notch - The posterior border lies on each side of the vertebral column - The inferior border surrounds the base lingula Posterior border Anterior border inferior borderv  lateral surface - 2 surfaces : - lateral (costal) related to ribs and intercostal spaces - medial (mediastinal) related to the heart and structures in the mediastinum - The medial surface contains the HILUM through which contains : - Pulmonary artery - 2 pulmonary veins - Main bronchus. - beonchial vessels - bronchopulmonary lymph nodes - Autonomic fibers Blood supply: Bronchial artery, branch of descending aorta Bronchial veins drain into azygous and hemiazygous vein Nerve supply: Pulmonary plexus of autonomic nerve  Bronchopulmonary Segments The bronchopulmonary segments are the anatomic, functional, and surgical units of the lungs Area of lung supplied by tertiary bronchus (segmental bronchus) Characteristics: Subdivision of a lung lobe Pyramidal in shape with its apex toward the lung root Surrounded by connective tissue Each segment has : - a segmental bronchus - segmental branch of pulmonary artery, - branches of pulmonary veins run between segments - lymph vessels, and autonomic nerves Because it is a structural unit, a diseased segment can be removed surgically  Comparison between 2 lungs RT lung LT lung Height Short, wide long, narrow Weight heavy light Fissures 2 (oblique & horizontal) 1 (oblique) Lobes 3 (upper, middle &lower) 2 (upper & lower) Cardiac notch and lingual Absent Present In anterior border Segments 10 8