Anatomy and Physiology of the Respiratory Tract.pptx

Anatomy and Physiology of the Respiratory Tract.pptx

1. Anatomy and Physiology of the Respiratory Tract Rasha abulubbad

2. Upper Respiratory Tract الجهاز التنفسي العلوي Nasal Cavity Oral Cavity Pharynx Larynx

3. Nasal Cavity التجويف ال أنفي Heats, humidifies, filters, resonates sound, and olfaction Velum elevates during the swallow, closes the nasal cavity, and prevents nasal regurgitation

4. Oral Cavity تجويف الفم Primary role is respiration, but is also used for swallow, digestion and speech  Lips - seal oral cavity for swallow Tongue - oral prep, oral transit (base of tongue is the primary muscle used to propel food - it rests on hyoid bone) Salivary Glands - secrete lubrication

5. Muscular tube that is dual passageway for respiration and swallow The 3 segments are: 1)Nasopharynx 2) Oropharynx Gag reflex (13% no gag-not predictor of dysphagia) 3)Laryngopharynx - separates digestive and respiratory tracts Pharynx: البلعوم

6. Pharynx: البلعوم Vallecula Recess between base of tongue and epiglottis Common landmark during intubation   Pharyngeal muscles  Suspended from hyoid bone for laryngeal elevation and anterior motion Epiglottis Separates the respiratory and digestive system for airway protection Acts like a rudder to deflect food laterally away from the airway

7. Larynx الحنجرة Cricoid Cartilage Thyroid Cartilage (Adam's Apple) Arytenoid Cartilages Along with muscles, responsible for opening and closing vocal cords Larynx is the "gatekeeper" to prevent aspiration at multiple levels   Pharyngeal Muscles - Muscles attached to hyoid elevate larynx up and pull it forward   Laryngeal Muscles - Close larynx at vocal fold level to create a seal that separates airway from digestive tract

8. Esophagus المريء Muscular organ for swallow Peristalsis Cricopharyngeal Sphincter or Upper Esophageal Sphincter Muscular band that relaxes to allow food to enter esophagus when larynx elevates & pulls forward, and pressures change

9. Innervation of the upper airway the upper airway is innervated by three main cranial nerves: Trigeminal nerve (Cranial nerve V): Branches of the trigeminal nerve innervate the nose and the anterior two thirds of the tongue. Glossopharyngeal (Cranial nerve IX): Branches of the glossopharyngeal nerve innervate the posterior third of the tongue, roof of pharynx and tonsils. Vagus (Cranial nerve X): The two major divisions of the vagus nerve in airway innervation are the superior laryngeal and the recurrent laryngeal nerves.

10. Sensory innervation 1. Trigeminal nerve – the sensory innervation of the nasal mucosa arises from two divisions: – The anterior ethmoidal nerve supplies the anterior septum and lateral wall; – The nasopalatine nerves from the sphenopalatine ganglion innervate the posterior areas. 2. Glossopharyngeal nerve – supplies the posterior third of the tongue, soft palate, epiglottis, fauces and the pharyngo- oesophageal junction. 3. Superior laryngeal nerve – the internal branch of the vagus nerve innervates mucosa from the epiglottis to and including the vocal cords. 4. Recurrent laryngeal nerve – a branch of the vagus nerve innervates mucosa below the vocal chords to the trachea.

11. Motor innervation 1. The external branch of the superior laryngeal nerve is responsible for innervation of the cricothyroid muscle. 2. The recurrent laryngeal nerve provides a motor supply to all the muscles of the larynx (posterior and lateral cricoarythenoid muscles) except the cricothyroid muscle. The lateral cricoarythenoid adducts the cords The posterior cricoarythenoid abducts the cords Unilateral damage to the recurrent laryngeal nerve causes hoarseness. Bilateral damage causes respiratory distress and stridor whilst chronic damage can cause aphonia.

12. Lower Respiratory Tract الجهاز التنفسي السفلي Trachea Bronchi Right and left mainstem Bronchioles Alveoli - air sacs  Lined with surfactant, filled with air to prevent collapse/ atelectasis

13. Lower Respiratory Tract الجهاز التنفسي السفلي Lungs Fill the thorax Highly elastic properties- elastic recoil Cradled in Pleura Visceral Pleura (Covers the lung surface) Parietal Pleura ( Lines the chest wall)   Pleural fluid is lubricant, and pleural space maintains negative pressure that holds lungs open (opposes the elastic recoil)

14. Muscles of Respiration عضلات التنفس  Respiratory Muscles – Inhalation Diaphragm (phrenic nerve at C3, 4, and 5) Intercostals  Pectoralis Major and Minor Strap Muscles of Neck Sternocleidomastoid Scalene Muscles

15. Neurophysiology of Breathing Respiratory Control Center - Brainstem Medulla Oblongata Pons Chemoreceptors  CO2 and O2 levels define inspiration and respiratory drive Stretch Receptors Define exhalation

16. Diseases الأمراض Obstructive Disorders COPD (Chronic Obstructive Pulmonary Disease) Irreversible airway obstruction Caused by damaged lung tissue Chronic Bronchitis Chronic cough, mucus production, narrow airways secondary to irritation Bronchospasm Emphysema Deterioration in alveolar walls  Loss of elastic recoil  Flat diaphragm

17. Diseases الأمراض Restrictive disorder’s Reduced lung volumes  Decreased compliance (stiff lungs)  Inability to take deep breaths Connective Tissue Disorders - fibrotic changes (scleroderma, lupus, pulmonary fibrosis)  Thoracic Deformities - reduced volumes (arthritis, scoliosis, kyphosis, rib fractures) Pneumonia - infection and inflammation (bacterial, viral or aspiration)

18. Neuromuscular Disorders الاضطرابات العصبية العضلية Degenerative Diseases that affect respiratory muscles ALS Guillain-Barré Polio Spinal Cord Injury Ms MD

19. Diseases الأمراض Cardiopulmonary Conditions - poor circulation of blood to lungs/body "cardiac cripple" Right Heart Failure Dependent edema Left Heart CHF Both Sides Total failure

20. Diseases الأمراض ARDS Adult Respiratory Distress Syndrome Damage to alveolar-capillary membrane resulting in severe impairment of gas exchange (fibrotic changes may be permanent) Multi-Factorial Stroke, trauma, infection, sepsis, severe pneumonia, inhalation injury, etc.