Respiratory System

1. Respiratory System Pathology 91 Spring 2012

2. Respiratory System Anatomy • Divided into: • Upper respiratory tract • Lower respiratory tract • Thoracic cavity • RT & LT pleural cavities • Mediastinum • Lined by parietal pleura • Visceral pleura adheres to the lung tissue • Bones of thorax assist in inspiration & expiration • Sinuses • are lined with respiratory epithelium • communicate with visceral cavities

3. Upper & Lower Respiratory Tracts • Upper • Nose • Mouth • Pharynx • Larynx • Lower • Trachea • Bronchi • Alveoli • Lungs

4. Mediastinum • Anterior • Thyroid & thymus glands • Middle • Heart • Great vessels • Esophagus & trachea • Posterior • Descending aorta

5. Mediastinum Frontal Radiograph • Superior vena cava • RT atrium • Inferior vena cava • Arch of aorta • LT pulmonary trunk • LT pulmonary artery shadow • Auricle of LT atrium • LT ventricle • LT cardiophrenic angle Retrieved from :www.liv.ac.uk/.../mbchb/hrtatk/images/ha1.jpg

6. The Importance of CXR’s • It is the most common diagnostic exam • It becomes routine • Improper techniques

7. Poor Inspiration vs. Sufficient Inspiration • Sufficient inspiration • Average movement of lungs and diaphragm between inspiration and expiration is 3 cm

8. Manual techniques Consistent Techniques Daily radiographs Analyze changes in pathology after treatment Or the progression the disease Must have optimal kVp and mAs Use PSP plates They offer a wider latitude KVp is increased to decrease PT dose Film Screen vs. CR / DRand Technique Considerations

9. Additive- harder than normal to penetrate Requires an increase in exposure factors These are pathologies that add fluid or tissue to normal aerated chest EX: pneumonia Subtractive- easier than normal to penetrate These pathologies increase aeration in the chest EX: emphysema Reduces exposure factors required Additive & Subtractive Pathologies

10. Additive and Subtractive Examples

11. Technique Adjustments for Different Image Receptors • Film Screen • mAs adjustment • kVp adjustments changes contrast • With a digital system • kVp should be adjusted • To reduce PT dose

12. AEC Sensors and Pathologies • AEC requires careful thought in regards to where pathology is in relation to sensors • Portable AEC • consistent exposure accuracy • less sensors • Sensors should be carefully selected

13. CXR Projections

14. PA: Upright vs. Recumbent • Upright: • Recumbent:

15. AP CXR’s • Usually seen in Portable exams • Best to be performed upright to demonstrate air/fluid levels • Maintain beam perpendicular to plane of IR • To prevent foreshortening of the heart • Use 72” • To reduce heart magnification • Longer SID reduces magnification • Short OID reduces magnification (this is why PA is preferred)

16. Lateral CXR • Left lateral places heart closer to IR • Heart is on left • 72” SID for reduced heart magnification

17. Lateral Decubitus CXR For diagnosis of free air in the pleural space or pleural fluid

18. Lordotic Chest • Useful in demonstrating apical regions of the lung • Apices are normally obscured by bony structures • TB likes to reside in apices

19. Soft tissuesof chest • Can see pectoral muscles • Breast shadows • Sometimes breasts obscure costophrenic angles • Nipple shadows • Implants

20. Mediastinal Radiographs and Pathologies

21. Sail Sign • Mediastinum appears large • Thymus is large on healthy infant • Radiographic Appearance: • AP- thymus extends beyond heart borders • Lateral- may fill anterior portion of mediastinum

22. Sail Sign

23. Mediastinal Emphysema(Pneumomediastinum) • Sudden rise in intraalveolar pressure that causes alveolar rupture. • Can be spontaneous • Severe coughing, vomiting or straining • Can result from trauma • Endoscopy • Injury

24. Mediastinal Emphysema(Pneumomediastinum)

25. Spontaneous: If there is no pneumothorax, no treatment is necessary Usually resolves in a few days without complications Other than spontaneous: Rupture in esophagus (usually from vomiting) Major bronchus trauma (trauma) Both need prompt diagnosis & surgical intervention Esophogram can verify a leak has not occurred. Treatment of Mediastinal Emphysema

26. Subcutaneous Emphysema • Can be caused by: • Severe pneumomediastinum • Penetrating or blunt injuries • Usually in chest and/or neck • Crackling sound or sensation

27. Subcutaneous Emphysema

28. Congenital and Hereditary Diseases Cystic Fibrosis Hyaline Membrane Disease

29. Cystic Fibrosis • Generalized disorder from a genetic defect that affects the function of the exocrine glands • Involves many organs & nearly all exocrine glands • Other organs affected • Salivary glands • Small bowel • Pancreas • Biliary tract • Female cervix • Male genital organs • Most lethal genetic disease of white children

30. Cystic Fibrosis • Diffuse Interstitial disease • Nodular densities with mucoid impaction

31. Progression of Cystic Fibrosis • At birth lungs are normal • Progression: • Increased secretions from bronchial glands • Leads to obstruction of the bronchial glands • Obstruction leads to staph infections, • Followed by tissue damage: • atelectasis,(collapsed lung) and emphysema • Once progression is in motion it is hard to stop

32. Symptoms Chronic couth With sputum, vomiting & disturbed sleep Wheezing Recurrent Pulmonary infections Role of Radiography: CXR aid in diagnosis Early: bronchial thickening and hyperinflation Progression: brochiectasis, cyst, atelectasis, scarring, enlargement of pulmonary artery and RT ventricle, overflation of lungs and chest wall Cystic Fibrosis

33. Cystic Fibrosis Sinuses • Sinus x-rays & CT will demonstrate persistent opacification of sinuses

34. Prognosis: Determined by degree of respiratory involvement Respiratory failure is inevitable Death 20-30 years of age Treatment: Antimicrobial drugs Bronchodilators Respiratory P.T. With pneumothorax- chest tube With hemoptysis- embolizing involved brachial arteries Psychotherapy Cystic Fibrosis

35. Cystic Fibrosis

36. Hyaline Membrane Disease Respiratory Distress Syndrome (RDS) • Affects • Premature infants • Caused by immature surfactant producing system • What is surfactant? • Answer

37. RDS : Signs and Symptoms • Signs: • Rapid & labored breathing • Respiratory distress • Atelectasis worsening • In severe cases acidosis occurs • What is acidosis? • Answer

38. RDS • Severe atelectasis with a air-bronchogram sign • Life threatening • Underaeration • Fine granular appearance known as “ground glass”

39. Hyaline Membrane Disease With Air bronchogram sign

40. Treatment for RDS • Proper thermal environment • Satisfactory tissue oxygenation • Monitored by arterial blood gas • Artificial surfactant

41. Inflammatory Diseases

42. Pneumonia • 6th leading cause of death in U.S. • Most common lethal noscomial infection • Most frequent type of inflammation in the lung compromising pulmonary function • Causes include: • Bacteria • Virus • mycoplasmas

43. Infants & children Most common caused by viral pathogens In adolescents & young adults Most common causes Bacterial organisms termed mycoplasma pneumoniae In adults Most common causes: Streptococcus Staphylococcus Pneumococcus Haemophilus influenza Chlamydia pneumoniae Legionella pneumophila Pneumonia: Age related

44. Pneumonia: Classification by location • Lobar pneumonia • The inflammation effects entire lobe • Segmental pneumonia • A segment of the lung • Bronchopneumonia • Bronchi and alveoli • Interstitial pneumonia • Interstitial lung tissue

45. Lobar Pneumonia • Right sided lobar pneumonia

46. Segmental pneumonia

47. Bronchopneumonia

48. Interstitial Pneumonia

49. CXR’s for Pneumonia • Important in determining location of pneumonia • Appears as soft-patchy, ill defined alveolar infiltrates and pulmonary densities • Alveolar infiltration results when alveolar air spaces are filled with fluid or cells

50. Generalized Symptoms of Pneumonia • Cough • Fever • Sputum production (develops over days) • Tachypnea • Crackles during clinical examination