Forefront in Medical And Traumatic Emergencies

1. Forefront in Medical And Traumatic Emergencies BU College of Nursing December 16, 2004 Modesto T. Kapuno, MD, CSEE, MNSA

2. Respiratory System

3. Respiration • Ventilation: Movement of air into and out of lungs • External respiration: Gas exchange between air in lungs and blood • Transport of oxygen and carbon dioxide in the blood • Internal respiration: Gas exchange between the blood and tissues

4. Respiratory System Functions • Gas exchange: Oxygen enters blood and carbon dioxide leaves • Regulation of blood pH: Altered by changing blood carbon dioxide levels • Voice production: Movement of air past vocal folds makes sound and speech • Olfaction: Smell occurs when airborne molecules drawn into nasal cavity • Protection: Against microorganisms by preventing entry and removing them

5. Respiratory System Divisions • Upper tract • Nose, pharynx and associated structures • Lower tract • Larynx, trachea, bronchi, lungs

6. Nose External nose Nasal cavity Functions Passageway for air Cleans the air PSCCE w/goblet cells Humidifies, warms air Smell Along with paranasal sinuses are resonating chambers for speech Pharynx Common opening for digestive and respiratory systems Three regions Nasopharynx Oropharynx Laryngopharynx Nose and Pharynx

7. Nasal Cavity and Pharynx 1 2 3 4

10. Vocal Folds • Functions • Maintain an open passageway for air movement (thyroid and cricoid) • Epiglottis and vestibular folds prevent swallowed material from moving into larynx • Vocal folds are primary source of sound production

11. Trachea • Windpipe • Divides to form • Primary bronchi • Carina: Cough reflex • Dense regular connective tissue and smooth muscle reinforced with c-shaped cart. on the ant. surface. • Post. Trachea consists of elastic lig. and a bundle of muscle called the trachealis muscle • The lining of the trachea is pseudo stratified ciliated columnar epithelium with goblet cells

12. Pseudo stratified ciliated columnar epithelium with goblet cells

13. Tracheobronchial Tree • Conducting zone • Trachea to terminal bronchioles which is ciliated for removal of debris • Passageway for air movement • Cartilage holds tube system open and smooth muscle controls tube diameter • Respiratory zone • Respiratory bronchioles to alveoli • Site for gas exchange

14. Tracheobronchial Tree 1 2 Conducting zone 3 4 5 6 Respiratory zone 7

15. Bronchioles and Alveoli 1 2 3 4 5

16. Alveolus and Respiratory Membrane

17. Gas Exchange

18. Lungs • Two lungs: Principal organs of respiration • Right lung: Three lobes • Left lung: Two lobes • Divisions • Lobes, bronchopulmonary segments, lobules

19. Thoracic WallsMuscles of Respiration 1 2

20. Inspiration Active process involving the diaphragm and intercostal muscles

21. Expiration Usually passive -can become active using internal intercostals and abdominal muscles

22. Elasticity • Lungs are compliant- they have the ability to stretch and recoil like a balloon

23. Apnea and Dyspnea • Apnea- absence or cessation of breathing • Dyspnea- difficulty of breathing

24. Negative Intrapleural Pressure • -2 to -4 mm Hg pressure maintained in the pleural space to aid in… • Keeping lungs expanded • Return of blood to the heart

25. Alveolar Membrane • Surfactant and water layer • Alveolar wall- Simple squamous epithelium 3) Basement membrane of alveolar wall 4) Interstitial space 5) Capillary wall- Simple squamous epithelium 6) Basement membrane of cap wall

26. Alveolar Capillary Membrane

29. The factors that effect rate of gas exchange • Partial pressure gradients of O2 and CO2 • Surface area of alveolar membrane • Thickness of capillary-alveolar membrane • Ventilation- perfusion mismatch

30. Blood flow through the lungs • Two blood flow routes of the heart exist: • Major rout brings deoxygenated blood to the lungs via the pulmonary artery, to pulmonary capillaries, is oxygenated and returns to the heart through the pulmonary veins. • The second rout brings oxygenated blood to the tissues of the bronchi, down to the respiratory bronchioles. Oxygenated blood flows through the aorta, through bronchial arteries capillaries, where O2 is released. Deoxygenated blood from the proximal part of the bronchi returns to the heart through the bronchial vein and the azygose venous system.

31. Pleura • Pleural fluid produced by pleural membranes • Acts as lubricant • Helps hold parietal and visceral pleural membranes together

32. Ventilation • Movement of air into and out of lungs • Air moves from area of higher pressure to area of lower pressure • Pressure is inversely related to volume

33. Changing Alveolar Volume • Lung recoil • Causes alveoli to collapse resulting from • Elastic recoil and surface tension • Surfactant: Reduces tendency of lungs to collapse • Pleural pressure • Negative pressure can cause alveoli to expand • Pneumothorax is an opening between pleural cavity and air that causes a loss of pleural pressure

34. Compliance • Measure of the ease with which lungs and thorax expand • The greater the compliance, the easier it is for a change in pressure to cause expansion • A lower-than-normal compliance means the lungs and thorax are harder to expand • Conditions that decrease compliance • Pulmonary fibrosis • Pulmonary edema • Respiratory distress syndrome

35. Pulmonary Volumes • Tidal volume • Volume of air inspired or expired during a normal inspiration or expiration • Inspiratory reserve volume • Amount of air inspired forcefully after inspiration of normal tidal volume • Expiratory reserve volume • Amount of air forcefully expired after expiration of normal tidal volume • Residual volume • Volume of air remaining in respiratory passages and lungs after the most forceful expiration

36. Pulmonary Capacities • Inspiratory capacity • Tidal volume plus inspiratory reserve volume • Functional residual capacity • Expiratory reserve volume plus the residual volume • Vital capacity • Sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume • Total lung capacity • Sum of inspiratory and expiratory reserve volumes plus the tidal volume and residual volume

37. Respiratory Problems All respiratory problems can be categorized as: Impacting ventilation, Diffusion, or Perfusion Management can be initiated once this can be established

38. Upper airway obstruction Lower airway obstruction Chest wall impairment Neurogenic dysfunction Foreign body, epiglottitis Asthma, airway edema Trauma, muscular dystrophy CNS depressant drugs, stroke Ventilation

39. Inadequate O2 Alveolar pathology Interstitial space pathology Capillary bed pathology Fire, CO poisoning Lung disease, inhalation injury Pulmonary edema, drowning Severe artherosclerosis Diffusion

40. Inadequate blood volume/ Hgb Impaired circulation Capillary wall pathology Shock, anemia Pulmonary embolus Trauma Perfusion

41. Interventions • Ensure that the upper and lower airways are open and unobstructed • Provide assisted ventilations

42. Ventilation Requirements • Neurological control to initiate ventilation • Nerves between the brain stem and the muscles of respiration • Functional diaphragm and intercostal muscles • Alveoli that are functional and noncollapsed

43. Diffusion • Process of gas exchange between the air-filled alveoli and the pulmonary capillary bed • Gas exchange is driven by simple diffusion in which gases move from areas of high concentration of low concentration until equal

44. Interventions • Provide high flow O2 • Reduce inflammation of interstitial space

45. Diffusion Requirements • Alveolar and capillary walls that are not thickened • Interstitial space between the alveoli and capillary wall that is not enlarged or filled with fluid

46. Perfusion • Refers to the process of circulating blood through the pulmonary capillary bed

47. Interventions • Ensure adequate circulating volume and Hgb levels • Optimize left sided heart function

48. Perfusion Requirements • Adequate blood volume • Adequate Hgb in the blood • Pulmonary capillaries that are not occluded • Properly function left heart that provides smooth flow of blood through pulmonary capillary bed

49. Assessment Review • Scene size up • Wide variety of toxic environments resulting in deficient O2 • Initial Assessment • Recognition of life threats • Focused history • Physical exam

50. Signs of Life Threats • Altered LOC • Severe cyanosis • Absent BS • Audible stridor • One or two word dyspnea • Tachycardia • Pallor and diaphoresis • Retractions/ accessory muscle use