The Respiratory system

Functions Works closely with circulatory system, exchanging gases between air and blood: Works closely with circulatory system, exchanging gases between air and blood: Takes up oxygen from air and supplies it to blood (for cellular respiration). Takes up oxygen from air and supplies it to blood (for cellular respiration). Removal and disposal of carbon dioxide from blood (waste product from cellular respiration). Removal and disposal of carbon dioxide from blood (waste product from cellular respiration). Homeostatic Role: – Regulates blood pH. – Regulates blood oxygen and carbon dioxide levels.

External Respiration Ventilation Ventilation – exchange of air between lungs and atmosphere Gas Exchange in pulmonary capillaries Gas Exchange in pulmonary capillaries Breathing largely involuntary activity Breathing largely involuntary activity

Internal Respiration All cells require oxygen for metabolism All cells require oxygen for metabolism All cells require means to remove carbon dioxide All cells require means to remove carbon dioxide Gas exchange at cellular level Gas exchange at cellular level

Structures of Respiratory System upper respiratory tract upper respiratory tract – nose, mouth, pharynx, epiglottis, larynx and trachea lower respiratory tract lower respiratory tract – bronchial tree and lungs

Nose nasal cavity nasal cavity nasal septum nasal septum mucous membrane mucous membrane – mucus – cilia – olfactory receptors

Pharynx Nasopharynx Nasopharynx – Posterior to the nose – Contains adenoids or pharyngeal tonsils Oropharynx Oropharynx – Posterior to the mouth – Palatine tonsils Laryngopharynx Laryngopharynx – Superior to the larynx

Epiglottis Oropharynx and laryngopharynx serve as a common passageway for both food and air Oropharynx and laryngopharynx serve as a common passageway for both food and air Epiglottis acts as a lid or flap that covers the larynx and trachea (airway) so food does not enter the lungs. Epiglottis acts as a lid or flap that covers the larynx and trachea (airway) so food does not enter the lungs.

Larynx Also known as the voice box Also known as the voice box Glottis (vocal apparatus) Glottis (vocal apparatus) – vocal bands or vocal cords

Trachea Windpipe or airway Windpipe or airway Mucous membrane lining with cilia Mucous membrane lining with cilia Smooth muscle with c-shaped cartilage rings Smooth muscle with c-shaped cartilage rings divides into two branches: divides into two branches: – Right bronchi – Left bronchi

Bronchi Bronchus, singular Bronchus, singular C-shaped cartilage rings with smooth muscle C-shaped cartilage rings with smooth muscle Each bronchi divides into bronchioles Each bronchi divides into bronchioles Terminate in air sacs called alveoli Terminate in air sacs called alveoli

Alveoli Resembles a small balloon as it expands and contracts with the flow of air CO2 diffuses from the blood in the capillaries, enters the alveoli, and is exhaled On inspiration, O2 diffuses from the alveoli to enter the capillaries

Thoracic Cavity thoracic thoracic thorax thorax mediastinum mediastinum – heart – aorta – esophagus – bronchi – thymus

Right-3 lobesLeft-2 lobes Lungs trachea

Pleura each lung enclosed in pleura each lung enclosed in pleura parietal pleura (inner) parietal pleura (inner) visceral pleura (outer) visceral pleura (outer) pleural space or pleural cavity pleural space or pleural cavity lubricating fluid lubricating fluid

Diaphragm muscle separating chest and abdomen muscle separating chest and abdomen inspiration, diaphragm contracts and increases thoracic space inspiration, diaphragm contracts and increases thoracic space – air flows in expiration, diaphragm relaxes and decreases thoracic space expiration, diaphragm relaxes and decreases thoracic space – air flows out phrenic nerve phrenic nerve

Respiration external respiration - exchange of gases in lungs external respiration - exchange of gases in lungs internal respiration - exchange of gases within cells of the body organs and tissues internal respiration - exchange of gases within cells of the body organs and tissues ventilation - movement of air ventilation - movement of air

Pathology Breathing Disorders Chronic Obstructive Pulmonary Disease COPD (COLD) Chronic Obstructive Pulmonary Disease COPD (COLD) Dyspnea Dyspnea Bradypnea Bradypnea Tachypnea Tachypnea

COPD Asthma Asthma – bronchospasms, parosysmal, productive cough, – mucolytics, bronchodilators Chronic Bronchitis Chronic Bronchitis – mucosal swelling, productive cough, chest pain – expectorants, bronchodilators, steroids Emphysema Emphysema – barrel-chest, dyspnea, orthopnea

Influenza Acute infectious respiratory disease Acute infectious respiratory disease Viral Viral Fever, chills, headache, myalgia, anorexia Fever, chills, headache, myalgia, anorexia Avoid aspirin in children Avoid aspirin in children

Pleural Effusions Excess fluid in pleural cavity Excess fluid in pleural cavity associated with congestive heart failure, ascites, infectious lung diseases, trauma associated with congestive heart failure, ascites, infectious lung diseases, trauma diagnosis diagnosis – auscultation, percussion Empyema, hydrothorax, hemothorax, pnrumothorax, pyopneumothorax Empyema, hydrothorax, hemothorax, pnrumothorax, pyopneumothorax thoracentesis thoracentesis

Tuberculosis Infectious, highly communicable disease Infectious, highly communicable disease aerosol transmission aerosol transmission primary tuberculosis, tubercles primary tuberculosis, tubercles immunocompromised immunocompromised effects other organ systems effects other organ systems drug resistant strains drug resistant strains

Bronchopneumonia Inflammatory disease of lungs Inflammatory disease of lungs lobar, bilateral lobar, bilateral hemoptyisis hemoptyisis consolidation consolidation Pneumocystis carinii Pneumocystis carinii lavage lavage

Cystic Fibrosis Hereditary disorder, affects exocrine glands Hereditary disorder, affects exocrine glands systemic involvement systemic involvement – lungs, pancreas, digestive tract Viscous mucus blocks bronchioles Viscous mucus blocks bronchioles Gas exchange impaired Gas exchange impaired

Respiratory Distress Syndrome Surfactant Surfactant – decreases the surface tension of the alveoli – needed for alveoli to fill with air and expand (compliance) Infant respiratory distress syndrome (hyaline membrane disease) Infant respiratory distress syndrome (hyaline membrane disease) Adult respiratory distress syndrome Adult respiratory distress syndrome

Oncology Primary Pulmonary Cancer Primary Pulmonary Cancer Smoking is leading cause of ALL TYPES OF LUNG CANCERS Smoking is leading cause of ALL TYPES OF LUNG CANCERS common site: epithelium of bronchi common site: epithelium of bronchi – bronchogenic carcinoma – masses form and block air passages – metastasizes frequently to lymph noes, liver, bones, brain, or kidney