Respiratory System

1. Respiratory System • The process of exchanging gases between the atmosphere and body cells is called respiration.

2. Events of respiration • Exchange of gases between air in the lungs and the blood is called external respiration • Gas exchange between blood and body cells is called internal resp.

4. Nose or mouth Nasal cavity or oral cavity Pharynx Larynx Trachea Bronchi Bronchioles Alveoli The alveoli are the site for gas exchange in the body Pathway of air in the body

5. Epiglottis Diaphragm

7. Breathing Mechanism • Remember: Diffusion is a passive process, no energy is required. • Normal atmospheric pressure is 760 mm Hg

8. Inspiration • The diaphragm contracts (flattens) and moves downward. • Thoracic cavity enlarges; alveoli increase in diameter • The pressure within the lungs (and alveoli) falls about 2mm Hg below normal (758 mm Hg) • Air is sucked into the lungs bc of negative pressure

9. Expiration • Diaphragm relaxes (curved) • Thoracic cavity decreases in size and alveoli diameter decreases • Lung (and alveoli) pressure increases to about 1 mm Hg above normal (761 mm Hg) • Air is forced out of lungs (passive process)

11. Smoking • Smoking destroys the movement of cilia in the resp. system • This allows dirt and debris to enter the resp. system and mucus builds up in the nasal cavity • this build up results in smokers’ cough (an effort to manually breakup the accumulated mucus)

12. Smoking • Smokers’ cough leads to chronic bronchitis (infection of the bronchiole tubes) • Mucus production increases, the bronchioles thicken (less diameter)more difficult to breathe • Bronchioles lose elasticity and cannot adjust to pressure changes

14. Smoking • Air pressure increases enough to burst alveoli- this condition is called emphysema • With emphysema coughing worsens along with fatigue and wheezing • Emphysema can progress to cancer • 80% of all lung cancer is caused from smoking • 13% of those with lung cancer do not live past 5 years

22. Total lung capacity • the vital capacity plus the residual volume • average = 5800ml • varies with age, sex, and body size

23. Respiratory Volumes • One inspiration followed by expiration is a respiratory cycle • Tidal Volume-the amount of air that enters or leaves the lungs during a normal resting respiration (about 500 ml)

24. Respiratory Volumes • During forced maximalinspiration (deep breathing) additional quantities of air enter the lungs; this is called inspiratory reserve volume. • This can equal about 3,000 ml

25. Respiratory Volumes • During maximal forcedex(it)piration, about 1100ml of additional air can be expelled from the lungs; this is the expiratory reserve volume. • This leaves about 1200 ml of air in the lungs at all times – this is called residual volume

27. Vital capacity • The total of the inspiratory reserve volume, the tidal volume, and the expiratory reserve volume is the vital capacity (max in, normal, max out) • The adult average is about 4,600 ml. • This is the maximum amount of air a person can exhale after they have taken the deepest breath possible

28. Inspiratory capacity • The tidal volume plus the inspiratory reserve volume. • This is the maximum amount of air a person can inhale • average – 3500 ml

29. Functional residual capacity • the expiratory reserve volume plus the residual volume • equals the amount of air left in the lungs after normal expiration • average = 2300ml

31. Total lung capacity • A spirometer is used to measure lung capacity • Lung capacity measurements can be used as an initial diagnostic tool for emphysema, pneumonia, lung cancer, and asthma

33. Gas Transport • Oxygen is carried in the blood bound to the hemoglobin in RBC • Each hemoglobin molecule can combine with only four oxygen atoms • Hypoxia – oxygen deficiency

34. Alveoli

35. Hemoglobin

36. Respiratory Disorders

37. Pneumonia • an infection of the lungs, which can be caused by a variety of microorganisms, including viruses, bacteria, fungi, and parasites • causes inflammation of the lungs • symptoms: fever, chills, cough, unusually rapid breathing, breathing with grunting or wheezing sounds, chest pain • treated with antibiotics, antiviral meds

38. Tiger Woods w pneumonia

39. Bronchitis • viral infection of the bronchial tree • bronchioles swell and mucus (thick fluid) forms inside them, making it hard to breathe • symptoms: coughing up mucus and wheezing • treated with asthma medicines to reduce swelling and ease breathing

40. Bronchitis

41. Emphysema • chronic lung disease usually caused by smoking • damage to the alveoli • symptoms: Shortness of breath, barrel-shaped chest, wheezing, fatigue, losing weight without trying • treatment: no cure, but symptoms can be eased with supplemental oxygen and other meds

43. Asthma • chronic respiratory disease causing airway inflammation; the airways in the lungs are overly sensitive to certain triggers • linked to allergies, heredity, environment, weight • symptoms: attacks of wheezing, coughing, chest constriction & labored breathing • treated with meds such as inhaled steroids/anti-inflammatory

46. Tuberculosis • disease caused by bacteria that attack the lungs • bacteria destroy lung tissue and can actually create a hole in the lung • symptoms: a bad cough, pain in the chest, coughing up blood, fever, fatigue, chills • treated with antibiotics • latent TB (bacteria in body but not active causes small bump on test) vs. active TB (bacteria actively attacking lung tissue) • No bump means on TB skin test means you are negative for TB

47. Tuberculosis

48. Cystic Fibrosis • hereditary, recessive, caused by a gene/protein defect • chloride can’t be transported out of cells, so water diffuses indries out mucus, causing it to clog affect organs • affects lungs (more infections)& pancreas (prevents digestive enzymes from reaching intestines, causing decreased nutrient absorption) • treatments: antibiotics for infections, exercises to remove mucus from lungs, digestive enzymes mixed into foods

49. Cystic Fibrosis

50. Lung Cancer • Cigarette smoking causes an estimated 443,000 deaths each year, including approximately 49,400 deaths due to exposure to secondhand smoke. • Lung cancer is the leading cause of cancer death among both men and women in the United States, and 90 percent of lung cancer deaths among men and approximately 80 percent of lung cancer deaths among women are due to smoking.