RESP 1121 ABG PPT notes Questions With Complete Solutions

1. 2 parts of Total content of oxygen in blood are? - ANSWER Oxygen dissolved in plasma + Oxygen chemically bound to Hb 2. A healthy patient on R/A at sea level with normal body temp. Hgb is 15. PaO2 is 100 mmHg. SaO2 is 97%. Calculate the Total content of oxygen in the blood. - ANSWER (100 x .003) + (15 x 1.34 x .97), .3 + 19.5, 19.8 ml/dl 3. CaO2 normal - ANSWER 16-20 ml/dl 4. What SaO2 is associated with a PaO2 of 100 mmHg? - ANSWER 97% 5. What SaO2 is associated with a PaO2 of 60 mmHg? - ANSWER 90% 6. What SaO2 is associated with a PaO2 of 40 mmHg? - ANSWER 73% 7. What SaO2 is associated with a PaO2 of 27 mmHg? - ANSWER 50% 8. Dissociation Curve Flat portion occurs at? - ANSWER SaO2 greater than 90% 9. Flat portion of dissociation curve facilitates? - ANSWER Facilitates O2 loading at lungs even with low PaO2 10. Steep Portion of dissociation curve facilitates? - ANSWER Facilitates O2 unloading at tissues 11. Dissociation Curve Steep portion occurs at? - ANSWER SaO2 less than 90% (Occurs at capillaries) 12. 13. P50 value (Dissociation curve) - ANSWER 27 mmHg P90 value (Dissociation curve) - ANSWER 60 mmHg 14. Dissociation curve begins to drop sharply. - ANSWER 90% Spo2 and 60mmHg 15. 16. 17. 18. 19. 456 789 rule is only for? - ANSWER PaO2 and SpO2 If SpO2 is 70%, what is PaO2? - ANSWER 40 mmHg If SpO2 is 80%, what is PaO2? - ANSWER 50 mmHg If SpO2 is 90%, what is PaO2? - ANSWER 60 mmHg 1 gram of normal Hb can carry how much oxygen? - ANSWER Approx 1.34 ml of O2 20. Why is V/Q ratio low at bases? - ANSWER Low ventilation, high perfusion 21. Why is V/Q ratio high at apices? - ANSWER High ventilation, Low perfusion 22. If there is a High V/Q ratio, what could that indicate? - ANSWER Pulmonary Embolism 23. If there is a low V/Q ratio, what could that indicate? - ANSWER Obstructive Diseases (COPD, patient with bad pulmonary infection like pneumonia or fungal infection, pulmonary edema, and ARDS 24. Why is V/Q ratio low at bases even though ventilation is greater at bases? - ANSWER Because perfusion is higher 25. What happens to the PAO2 and PACO2 with High V/Q ratio? - ANSWER Higher PAO2 (132 mmHg), Lower PACO2 (32 mmHg) 26. What happens to the PAO2 and PACO2 with Low V/Q ratio? - ANSWER Lower PAO2 (89 mmHg), Higher PACO2 (42 mmHg) 27. Ideal V/Q ratio - ANSWER 1:1 (Where V/Q is in perfect balance) 28. Oxygen dissolved in Plasma Formula - ANSWER PaO2 x .003 29. A healthy patient on R/A at sea level with a normal body temp. The PaO2 at the lungs will be approx. 100 mmHg. Calculate oxygen dissolved in plasma - ANSWER (PaO2 x .003), (100 x .003) , 0.3 ml/dl 30. 31. 32. 33. Dissolved in plasma Unit measure - ANSWER ml/dl Pulmonary Embolism - ANSWER Blood clot in lungs Atelectasis - ANSWER Collapsed lung Why is blood flow (Perfusion) higher at bases? - ANSWER Gravity 34. 3 ways carbon dioxide is transported - ANSWER Dissolved in plasma, Bound to hemoglobin, and as bicarbonate ions 35. CO2 - ANSWER Carbon Dioxide 36. a/A ratio normal - ANSWER .9 37. 38. 39. 40. 41. 42. P/F ratio formula - ANSWER PaO2 / FiO2 P/F ratio normal - ANSWER 400 or more Mild Ards P/F ratio - ANSWER 300-200 Moderate Ards P/F ratio - ANSWER 200-100 Severe Ards P/F ratio - ANSWER < 100 P/F ratio is used to grade what? - ANSWER Ards severity 43. 44. 45. PvO2 normal - ANSWER 40 mmHg PvCO2 normal - ANSWER 46 mmHg PAO2 normal - ANSWER 100 mmHg 46. PACO2 normal - ANSWER 40 mmHg 47. 48. 49. PaO2 normal - ANSWER 80-100 mmHg PaCO2 normal - ANSWER 40 mmHg According to Fick's law, the greater? - ANSWER Surface area, diffusion constant, pressure gradient. More diffusion will occur 50. According to Fick's law, more diffusion will occur when? - ANSWER The greater the surface area (area available), Diffusion constant (thin membrane), pressure gradient 51. What is constant in healthy people in Fick's law? - ANSWER Greater surface area and diffusion constant. 52. What does diffusion depend on in the normal lung? - ANSWER Gas pressure gradients 53. Normal Pulmonary blood exposure time to alveolar gas? - ANSWER 0.75 second 54. Pulmonary blood exposure time to alveolar gas during exercise? - ANSWER During exercise may fall to 0.25 second 55. With no diffusion limitations, equilibration occurs in? - ANSWER As little as 0.25 second 56. With a diffusion limitation or blood exposure time of less than 0.25 second - ANSWER May be inadequate time for equilibration 57. 2 anatomic shunts - ANSWER Bronchial venous drainage and Thebesian venous drainage 58. The 2 anatomic shunts do what to CaO2? - ANSWER Lowers the CaO2 59. How do the 2 anatomic shunts lower the CaO2? - ANSWER Drain poorly oxygenated blood into arterial circulation, which lowers the CaO2. 60. PaO2 is normally 5-10mmHg less than PAO2 due to what? - ANSWER Anatomic shunts 61. What is another reason other than anatomic shunts that PaO2 is lower than PAO2? - ANSWER Regional inequalities in V/Q. 62. 2 reasons why PaO2 is 5-10 mmHg lower than PAO2? - ANSWER Anatomic shunts and regional inequalities in V/Q. 63. Changes in either V or Q affect what? - ANSWER Affect gas tensions 64. Apices V/Q ratio - ANSWER High V/Q ratio (>1 V/Q) ~3.3 65. (1:1) Middle lobe V/Q ratio - ANSWER Ideal V/Q ratio 66. Bases V/Q ratio - ANSWER Low V/Q ratio (<1 V/Q) ~0.66 67. Pulmonary Ventilation - ANSWER movement of air in and out of lungs 68. External Respiration - ANSWER Exchange of gases from lungs to blood (alveoli to blood) 69. Transport of gases - ANSWER Moving O2 and CO2 in blood (Dissolved + Bound forms) 70. Internal Respiration - ANSWER Gas exchange from blood to tissues 71. Cellular respiration - ANSWER Cellular use of O2 to produce energy (metabolism)