ANATOMY OF THE RESPIRATORY SYSTEM 8.10.2013 Kaan Yücel M.D., Ph.D. Vincent Van Gogh – Skull with Cigarette (1886) 8.10.2013 Kaan Yücel M.D., Ph.D.

MEDIASTINUM Mod. L. middle septum, L, mediastinus, midway

MEDIASTINUM

MEDIASTINUM

MEDIASTINUM

SUPERIOR MEDIASTINUM

ANTERIOR MEDIASTINUM

POSTERIOR MEDIASTINUM

Nose is divisible into : External nose Nasal cavity

External Nose Extends the nasal cavities onto the front of the face Pyramidal in shape

External nose has bony & cartilaginous parts. Bones Cartilages Nasal bones Lateral cartilages (paired) Frontal process of maxilla Alar cartilages (paired) Nasal part of frontal bone Septal cartilage (single)

Nasal cavITIES olfactory receptors separated from: uppermost parts of the respiratory tract olfactory receptors separated from: each other by a midline nasal septum oral cavity below by the hard palate cranial cavity above by parts of the frontal, ethmoid, &sphenoid bones. Posteriorly, each nasal cavity communicates with the nasopharynx through two openings choana.

Each nasal cavity consists of 3 regions. nasal vestibule internal to the naris respiratory region largest , rich neurovascular supply olfactory region @ apex of each nasal cavity, olfactory receptors 3 2 1

the most anterior part of the nasal cavity.

Functions of the nose & nasal cavities   Olfaction (sense of smell) Respiration Filtration of the dust in the inspired air Humidification and warming of the inspired air (cooling the internal carotid artery for brain) Reception of the secretions from the paranasal sinuses and nasolacrimal ducts

2. PARANASAL SINUSES Frontal sinuses Ethmoid sinuses Sphenoid sinuses air filled spaces lying within the bones around the nasal cavity lined by respiratory mucosa. open into the nasal cavities innervated by branches of the trigeminal nerve [V]. Frontal sinuses Ethmoid sinuses Sphenoid sinuses Maxillary sinuses

organ of phonation (vocalization) 3. LARYNX between C3- C6 organ of phonation (vocalization) continuous below with the trachea above opens into the pharynx immediately posterior & slightly inferior to the tongue Cartilage Muscles Connective tissue

SKELETON OF LARYNX LARYNGEAL CARTILAGES Unpaired cartilages Thyroid cartilage (biggest) Cricoid cartilage Epiglottic cartilage Paired cartilages Arytenoid Corniculate Cuneiform

Thyroid cartilage largest cartilage of the larynx 2 laminae which fuse anteriorly at the thyroid angle & form laryngeal prominence (Adam’s apple)

Cricoid cartilage a ring shaped cartilage, most inferior of the laryngeal cartilages Inferiorly attaches to 1st tracheal ring via cricotracheal ligament. Completely encircles the airway Broad lamina of cricoid cartilage posteriorly Narrower arch of cricoid cartilage anteriorly

Arytenoid cartilages pyramidal in shape 3 processes Apex (superior) articulation w/corniculate cartilage Vocal process (anterior) vocal ligament attaches here Muscular process (lateral) posterior & lateral crico-arytenoid muscles

Epiglottic cartilage (Epiglottis) a leaf-shaped cartilage attached by its stem to the posterior aspect of the thyroid cartilage @ the angle Most superior end is free.

Corniculate & cuneiform cartilages corniculate cartilages two small conical cartilages Located on the arytenoid cartilages cuneiform cartilages small cartilages anterior to corniculate cartilages lie in the posterior part of the aryepiglottic fold.

EXTRINSIC LIGAMENTS OF THE LARYNX . Thyrohyoid membrane Below superior margin of the thyroid cartilage, above hyoid bone lateral thyrohyoid ligament (posterior thickening), triticeal cartilage median thyrohyoid ligament (midline thickening) Hyo-epiglottic ligament from the midline of the epiglottis to the body of hyoid bone Cricotracheal ligament between lower border of cricoid cartilage & upper border of 1st tracheal cartilage

Fibroelastic membrane of the larynx INTRINSIC LIGAMENTS OF THE LARYNX . Fibroelastic membrane of the larynx lies under the mucosa of the larynx links together the laryngeal cartilages completes the architectural framework of the laryngeal cavity forms some of the ligaments between the cartilages.

Fibroelastic membrane of the larynx INTRINSIC LIGAMENTS OF THE LARYNX . Fibroelastic membrane of the larynx 2 parts lower conus elasticus upper quadrangular membrane

cricothyroid ligament, cricovocal membrane, cricothyroid membrane Conus elesticus cricothyroid ligament, cricovocal membrane, cricothyroid membrane Free upper margin thickens & forms vocal ligament  vocal fold opening between the 2 vocal folds (rima) glottis median cricothyroid ligament anterior midline thickening of conus elasticus

cricothyroid ligament, cricovocal membrane, cricothyroid membrane Conus elasticus cricothyroid ligament, cricovocal membrane, cricothyroid membrane Each vocal ligament free upper margin attaches to anterior part of inner surface of thyroid cartilage @ thyroid angle posteriorly attach to vocal processes of the arytenoid cartilages.

Rima glottis Inspiration Widens Phonation Narrows- 2 vocal fold come together Pitch increases with tensing, decreases by relaxation. Intensity of expiration determines the loudness of sound.

Quadrangular membrane . vestibular ligament attached posteriorly arytenoid cartilage anteriorly thyroid angle superior to the attachment of the vocal ligament. lateral margin of epiglottis free lower margin is thickened anterolateral surface

Quadrangular membrane . vestibular ligament attached posteriorly arytenoid cartilage anteriorly thyroid angle superior to the attachment of the vocal ligament.

LARYNGEAL CAVITY tubular architectural support fibro-elastic membrane of the larynx laryngeal cartilages .

superior aperture (laryngeal inlet) V.S. inferior aperture 1) opens into anterior aspect of pharynx just below and posterior to the tongue continuous with the lumen of trachea completely encircled by cricoid cartilage

superior aperture (laryngeal inlet) V.S. inferior aperture 2) oblique and points posterosuperiorly into the pharynx horizontal in position

superior aperture (laryngeal inlet) V.S. inferior aperture 3) can be closed by downward movement of the epiglottis. continuously open

vestibular and vocal folds divide into three major regions LARYNGEAL CAVITY vestibular and vocal folds divide into three major regions Vestibule between laryngeal inlet & vestibular folds Middle part between vestibular folds & vocal folds Infraglottic space between the vocal folds & inferior opening of the larynx

separates middle chamber from infraglottic cavity. base Rima glottidis between vocal folds separates middle chamber from infraglottic cavity. base formed by interarytenoid fold @ bottom of interarytenoid notch. .

LARYNGEAL MUSCLES MOVE THE LARYNX AS A WHOLE INTRINSIC LARYNGEAL MUSCLES EXTRINSIC LARYNGEAL MUSCLES MOVE THE LARYNX AS A WHOLE move the laryngeal components altering the length and tension of the vocal folds and the size and shape of the rima glottidis

TENSOR OF THE VOCAL LIGAMENT * Superior laryngeal nerve . TENSOR OF THE VOCAL LIGAMENT Pulls the thyroid angle anteriorly/inferiorly

RELAXER OF THE VOCAL LIGAMENT . RELAXER OF THE VOCAL LIGAMENT pulls the arytenoid cartilages anteriorly, toward the thyroid angle relaxes the vocal ligaments to lower the pitch of the voice.

Phonation Adductors of the vocal cords lateral crico-arytenoid muscles . lateral crico-arytenoid muscles muscular processes anterior vocal processes medial transverse and oblique arytenoid muscles Vibration of vocal ligaments Phonation

Abductors of the vocal cords posterior crico-arytenoid muscles

FUNCTIONAL ANATOMY OF THE LARYNX Respiration Quiet: laryngeal inlet, rima glottidis open arytenoid cartilages abducted Forced: rima glottidis widens arytenoid cartilages rotated laterally, vocal folds abducted

FUNCTIONAL ANATOMY OF THE LARYNX Effort closure occurs when air is retained in the thoracic cavity to stabilize the trunk increasing intra-abdominal pressure Rima glottidis is completely closed. Completely and forcefully shut the airway

FUNCTIONAL ANATOMY OF THE LARYNX Phonation arytenoid cartilages & vocal folds adducted rima glottidis closed Air is forced through the closed rima glottidis Vocal folds vibrate against each other and produce sounds. Tension in the vocal folds adjusted by vocalis & cricothyroid muscles

FUNCTIONAL ANATOMY OF THE LARYNX Swallowing Rima glottidis closed. Laryngeal inlet narrowed Larynx moves up & forward – opens the esophagus attached to the posterior aspect of the lamina of cricoid cartilage Epiglottis goes down toward the arytenoid cartilages laryngeal inlet narrowed or closed .

External carotid artery Subclavian artery

Cricothyroid muscle recurrent (inferior) laryngeal nerve

from the inferior end of larynx to the level of T5-T6 . from the inferior end of larynx to the level of T5-T6 Terminates by dividing into right & left main bronchi @ sternal angle. Main bronchi give branches inside the lungs & form bronchial tree.

formed of tracheal rings which are incomplete posteriorly Posterior parts of the tracheal rings closed by smooth muscle trachealis muscle. .

5. PLEURA covers the pulmonary cavities and external surfaces of the lungs in these cavities visceral pleura invests all surfaces of the lungs parietal pleura lines the pulmonary cavities & thorax’s inner surface

Visceral pleura insensitive to pain Parietal pleura extremely sensitive to pain Irritation causes local pain or referred pain projecting to the dermatomes supplied by the same spinal nerve.

pleural cavity contains a capillary layer of serous pleural fluid potential space between the layers of pleura contains a capillary layer of serous pleural fluid lubricates the pleural surfaces allows layers of pleura slide smoothly over each other during respiration. lung surface in contact with thoracic wall lung expands fills with air when thorax expands

5. LUNGS organs of respiration lie on either side of the mediastinum surrounded by right & left pleural cavities

5. LUNGS Air enters and leaves the lungs via main bronchi branches of trachea Inspired air into close relation with venous blood in pulmonary capillaries.

5. LUNGS Apex upper pole 3 surfaces costal, mediastinal and diaphragmatic Root of the lung 2 lobes in the left lung oblique fissure 3 lobes in the right lung horizontal & oblique fissures

Tracheobronchial Tree sublaryngeal airway Trachea @ superior mediastinum TRUNK OF THE TREE Bifurcation @ sternal angle Main bronchi Right main bronchus & Left main bronchus enter hilum of the lung Branches of the tracheobranchial tree

Tracheobronchial Tree Main (primary) bronchus Secondary (lobar) bronchi 2 on the left, 3 on the right Tertiary (segmental) bronchi .

BRONCHOPULMONARY SEGMENTS largest subdivisions of a lobe Pyramidal-shaped segments of the lung apices facing the root of the lung. Separated from adjacent segments by connective tissue septa.

BRONCHOPULMONARY SEGMENTS largest subdivisions of a lobe Segmental bronchus & Tertiary branch of pulmonary artery Drained by intersegmental parts of the pulmonary veins

BRONCHOPULMONARY SEGMENTS largest subdivisions of a lobe Named according to the segmental bronchi supplying them. Usually 18-20 in number Surgically resectable.

tertiary segmental bronchi conducting (lobular) bronchioles end as terminal bronchioles respiratory bronchioles pulmonary alveolus basic structural unit of gas exchange in the lung

Branching of the bronchial tree Trachea Principal bronchus Lobar bronchi (secondary bronchi) Segmental bronchi (tertiary bronchi) Terminal bronchiol Respiratory bronchiol Alveolar duct Alveolar sac Alveolus

mediastinal pleura reflects off mediastinum root of the lung mediastinal pleura reflects off mediastinum a sleeve-like covering for airway, vessels, nerves, lymphatics which pass between the lung and mediastinum

hilum of lung The root of the lung joins medial surface of the lung here! mediastinal pleura continuous with visceral pleura @ hilum of the lung.

Vasculature of pleaura & lungs 1 pulmonary artery (venous blood) 2 pulmonary veins (arterial blood) Each lobe and segment its own artery Branching of the arteries follow the bronchial tree Terminate as capillaries around the alveols.

Vasculature of pleaura & lungs Veins of the parietal pleura drain into systemic veins mainly through the intercostal veins.

BRONCHIAL ARTERIES follow bronchial tree as far as respiratory bronchioles. Left bronchial arteries from thoracic aorta paired Right bronchial artery usually arises from 3rd posterior intercostal artery single artery.

BRONCHIAL VEINS Right bronchial vein into azygos vein Left bronchial vein into accessory hemiazygos vein.

pulmonary plexuses parasympathetic innervation vagus nerve bronchoconstrictor, vasodilator to the lung vessels, secretomotor to the glands sympathetic sympathetic trunk bronchodilator, vasoconstrictor to the lung vessels, inhibitor to glands parietal pleura intercostal & phrenic nerves