1 / 39

Physiology Review

Physiology Review. Respiratory System. Introduction. This presentation does NOT cover lecture 25 External versus internal respiration RQ = CO 2 produced / O 2 consumed Thoracic cavity Pleurisy & pleural effusion Conducting versus respiratory zones Alveoli Mucociliary transport

chuck
Télécharger la présentation

Physiology Review

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Physiology Review Respiratory System Chris Mason, MS, MS-I

  2. Introduction • This presentation does NOT cover lecture 25 • External versus internal respiration • RQ = CO2 produced / O2 consumed • Thoracic cavity • Pleurisy & pleural effusion • Conducting versus respiratory zones • Alveoli • Mucociliary transport • Sol & gel layers • Ciliary dyskinesia • Silicosis • Other defects Chris Mason, MS, MS-I

  3. Lung Volumes & Capacities Chris Mason, MS, MS-I

  4. Lung Volumes & Capacities Chris Mason, MS, MS-I

  5. Lung Volumes & Capacities Chris Mason, MS, MS-I

  6. Lung Volumes & Capacities • Patient with tidal volume of 0.5 L is breathing at 15 breaths / minute • PCO2 arterial blood is 40 mm HG • PCO2 expired air is 36 mm Hg • What is alveolar ventilation rate Chris Mason, MS, MS-I

  7. Lung Volumes & Capacities Chris Mason, MS, MS-I

  8. Lung Volumes & Capacities • = (VT – dead space air) x breaths / minute • = (0.5 L – 0.05 L) x 15 breaths / minute • = 0.45 L x 15 breaths / minute • = 6.75 L / breath / minute Chris Mason, MS, MS-I

  9. Breathing Mechanics • Muscles of inspiration • Diaphragm • Most important • When diaphragm contracts • Stomach contents pushed down • Ribs lifted up & out • During exercise & respiratory distress • External intercostals • Accessory breathing muscles Chris Mason, MS, MS-I

  10. Breathing Mechanics • Muscles of expiration • Normally passive • Lung – chest wall system is elastic & normally returns to resting position after inspiration • During exercise & under conditions of ↑ airway resistance • Asthma • Abdominal muscles • Compress abdominal cavity • Push diaphragm up • Push air out of lungs • Internal intercostals • Pull ribs down & in Chris Mason, MS, MS-I

  11. Breathing Mechanics ↓ C → lungs least distensible ↑ C → lungs most distensible Chris Mason, MS, MS-I

  12. Breathing Mechanics Chris Mason, MS, MS-I

  13. Breathing Mechanics Chris Mason, MS, MS-I

  14. Breathing Mechanics Chris Mason, MS, MS-I

  15. Breathing Mechanics Chris Mason, MS, MS-I

  16. Breathing Mechanics • Relationships between pressure, airflow & resistance are analogous to those between blood pressure, blood flow & resistance in CV system Chris Mason, MS, MS-I

  17. Breathing Mechanics • Factors that change airway resistance • Major site of resistance is medium sized bronchi • Smallest airways are in parallel and therefore do NOT offer highest resistance Chris Mason, MS, MS-I

  18. Breathing Mechanics • Breathing cycle • At rest • During inspiration • During expiration Chris Mason, MS, MS-I

  19. Breathing Mechanics • Lung diseases • Asthma • COPD • Fibrosis Chris Mason, MS, MS-I

  20. Gas Exchange • Dalton’s law • Partial pressure = PTOTAL x fractional gas concentration • Partial pressures • Physiologic shunt • Dissolved gases • Henry’s law Chris Mason, MS, MS-I

  21. Gas Exchange • Diffusion of gases • Fick’s law • Perfusion-limited & diffusion limited gas exchange Chris Mason, MS, MS-I

  22. O2 Transport • O2 carried in blood either dissolved or bound to Hb • Hb, at its normal concentration, ↑ O2 carrying capacity of blood x 70 Chris Mason, MS, MS-I

  23. O2 Transport Chris Mason, MS, MS-I

  24. O2 Transport Chris Mason, MS, MS-I

  25. O2 Transport Chris Mason, MS, MS-I

  26. O2 Transport Chris Mason, MS, MS-I

  27. O2 Transport • Hypoxemia • Causes • ↑ altitude (↓ Patm) • ↓ PaO2 + normal A-a gradient • Hypoventilation (↓ PAO2) • ↓ PaO2 + normal A-a gradient • Diffusion defect (fibrosis) • ↓ PaO2 + ↑ A-a gradient • V / Q defect • ↓ PaO2 + ↑ A-a gradient • Right to left shunt • ↓ PaO2 + ↑ A-a gradient Chris Mason, MS, MS-I

  28. O2 Transport • Hypoxia • Causes • ↓ cardiac output via ↓ blood flow • Hypoxemia via ↓ PaO2 causing ↓ Hb % saturation • Anemia via ↓ [Hb] causing ↓ blood O2 content • CO poisoning via ↓ blood O2 content • Cyanide poisoning ↓ O2 utilization by tissues Chris Mason, MS, MS-I

  29. CO2 Transport Chris Mason, MS, MS-I

  30. Pulmonary Circulation • Pressures, resistance & cardiac output • Distribution of pulmonary blood flow • Supine versus standing • Zones 1, 2 & 3 of lungs Chris Mason, MS, MS-I

  31. Pulmonary Circulation • Regulation of pulmonary blood flow • Shunts Chris Mason, MS, MS-I

  32. Ventilation / Perfusion Defects Chris Mason, MS, MS-I

  33. Ventilation / Perfusion Defects Chris Mason, MS, MS-I

  34. Control of Breathing • Sensory information (PCO2, lung stretch, irritants, muscle spindles, tendons & joints) is coordinated in the brain stem • Medulla & pons • Brain stem output controls respiratory muscles & breathing cycle • Central control • Chemoreceptors • Other receptors Chris Mason, MS, MS-I

  35. Control of Breathing • Central control continued Chris Mason, MS, MS-I

  36. Control of Breathing • Chemoreceptors • Central • Peripheral Chris Mason, MS, MS-I

  37. Control of Breathing • Other receptors Chris Mason, MS, MS-I

  38. Integrated Responses • Exercise Chris Mason, MS, MS-I

  39. Integrated Responses • Adaptation to high altitude Chris Mason, MS, MS-I

More Related