upper respiratory air ways.pdf

Respiratory system Upper airways Prepared by dr Hatoon abdelkareem components of RESPIRATORY SYSTEM : - Nose - Pharynx - Larynx - Trachea - Bronchial tree - Lungs  NOSE formed of external nose and nasal cavity....

Respiratory system Upper airways Prepared by dr Hatoon abdelkareem components of RESPIRATORY SYSTEM : - Nose - Pharynx - Larynx - Trachea - Bronchial tree - Lungs  NOSE formed of external nose and nasal cavity.  External nose: formed of upper bony part lower cartilaginous part. Parts of external nose Nasal bridge Ala Nostril  Nasal cavity: - There are two nasal cavities separated by a nasal septum. - Each cavity opens on the face through the anterior nasal opening ( nares or nostril) nasopharynx - opens posteriorly in the nasopharynx through the posterior nasal opening (choana) Nasal cavity has: roof Lateral wall Medial wall floor  Frontal Cribriform plate of bone ethmoid Body of Roof sphenoid Nasal Anterior sloping part: bone Nasal Frontal bones. Middle horizontal part: The cribriform plate of ethmoid bone. Posterior sloping part: body of sphenoid Floor Palatine process of maxilla Horizontal plate of palatine bone Palatine process Horizontal plate of maxilla of palatine bone  Perpendicular plate of ethmoid Septal cartilage Vomer Source: Netter atlas of Anatomy Septal cartilage: Medial wall Perpendicular plate of ethmoid (nasal septum) Vomer  Superior concha (turbinate) middle concha (turbinate) superior meatus inferior concha (turbinate) Middle meatus Inferior meatus Its lateral wall has three elevations called superior, middle and Lateral wall inferior conchae that are separated by three meatuses receiving openings of the para-nasal sinuses Its lateral wall has three elevations called superior, middle and inferior conchae that are separated by three meatuses receiving openings of the para-nasal sinuses Superior Superior meatus concha Middle meatus Inferior Middle meatus concha Inferior concha  Olfactory mucosa Nasal mucosa Respiratory mucosa 1- Vestibule : contain hair prevent dust from entering 2- Respiratory mucosa warm inspired air 3- Olfactory mucosa The upper part , responsible for olfaction ( smell) Vestibule Source: Gray’s Anatomy for Students  Applied anatomy 1- deviated nasal septum 2- turbinates hypertrophy Both may cause difficulty in breathing Functions of the nose: 1. Smell. 2. Filtration and warming of the inspired air. 3. Nasal conchae increase the surface area of the nasal cavity which magnifies the turbulence of air and thus improves olfaction. Paranasal air sinuses  Frontal air sinus  Paranasal sinuses: They are air-filled spaces in the skull bones surrounding the nose (pneumatic bones) and open in Ethmoidal the nasal meatuses. air sinus  Functions of paranasal sinuses 1. Decrease the weight of the skull. 2. Increase the resonance of voice. 3. They act as air cushions ( protection ) Maxillary air sinus for the brain, eye and pituitary gland Spenoidal air sinus Source: Gray’s Anatomy for Students Frontal sinus present in the frontal bone drain into the middle meatus Frontal sinus Maxillary sinus: Maxillary sinus: The largest air sinus present in the maxilla The only sinus present at birth Opens at the middle meatus  sphenoidal sinus Sphenoidal sinus: It occupies the body of the sphenoid bone below pituitary gland It opens above the superior concha Ethmoidal sinuses Three groups : Anterior ethmoidal sinus Ethmoidal sinuses Middle ethmoidal sinus Posterior ethmoidal sinus Applied anatomy : Sinusitis : Inflammation of sinuses due to retention of mucus secretion inside the sinuses  pharynx - Funnel-shaped muscular tube about 12 cm long, lies behind the nasal cavity, oral cavity and larynx. - Extends from the base of the skull to the level of 6th cervical vertebra (C6) where It continues as the esophagus  pharynx is divided into 3 parts 1-Nasopharynx: It lies behind the nasal cavity, 2- Oropharynx: It lies behind the oral (mouth) cavity 3- Laryngopharynx: It lies behind the larynx.  Nasopharynx: It lies behind the nasal cavity, adenoid - acts as a passage for air only. - Its upper part contains the nasopharyngeal tonsil (adenoid) while the lower part shows the opening of Eustachian tube enlarged adenoid may lead to 1- difficulty in breathing 2- Nasal tone Eustachian tube 3- Mouth breathing  Oropharynx: It lies behind the oral (mouth) cavity - acts as a passage for food and air. - Its lateral wall contains the palatine tonsil. Laryngopharynx: It lies behind the larynx and acts as a passage for food only. larynx Larynx: - It is a tube consisting of 9 cartilages (3 single and 3 paired) connected together by membranes and ligaments and moved by special muscles. It extends from the root of the tongue till the beginning of trachea at the level of C6 vertebra. It contains the vocal cords which are responsible for production of voice. Function: 1. Passage of air to trachea and lungs. 2. Production of voice by vocal cords. 3. Reflex expulsion of foreign bodies. Laryngeal cartilages: A. Thyroid: Single hyaline cartilage, forms a median elevation called the laryngeal prominence (Adam apple) B. Cricoid: Single hyaline cartilage, shaped like signet ring C. Epiglottis: single elasic caritlage,, behind the root of the tongue, closes the laryngeal orifice during swallowing D. Arytenoid: paired cartilages, shaped liked pyramids E. Cuneiform: paired lie in the aryepiglottic folds F. Corniculate: paired lie on the apices of the arytenoid cartilages  Ligaments of the larynx 1. Thyrohyoid membrane between the thyroid cartilage and the hyoid bone 3-Cricothyroid ligament between the cricoid cartilage and the thyroid cartilge 2. Conus elasticus (cricovocal) membrane, it is the lower part of the fibroelatic membrane lining the larynx. Its upper part is called Vocal folds (true vocal cord) Vocal folds (true vocal cords), contain the vocal ligament, important in voice production because they control the stream of air passing through the rima glottidis Rima glottids, is the space between the vocal folds and arytenoid cartilages, it is the narrowest part of the laryngeal cavity Muscles of the larynx responsible for controlling sound production. Adductors: - lateral cricoarytenoid - transverse arytenoid and oblique arytenoid - cricothyroid ( tenses and adducts) Abductors : posterior cricoarytenoid Nerve supply of the larynx All muscles of the larynx are supplied by recurrent laryngeal nerve external laryngeal nerve except cricothyroid muscle which is supplied by external laryngeal nerve recurrent laryngeal nerve Applied anatomy - Laryngitis: is inflammation and swelling of the larynx - Laryngomalacia is a congenital softening of the tissues of the larynx (voice box) above the vocal cords. - Lesion of the recurrent laryngeal nerve: occurs as a complication to thyroidectomy operation may cause: stridor hoarseness of voice aphonia