Patho 3

  1. Increased ratio of base to acid
    Alkalosis
  2. Decreased ratio of base to acid
    Acidosis
  3. pH of blood equals ...
    • hydrogen ion concentration
    • ratio of bicarb (base) to dissolved CO2 (acid)
  4. What is the significance of maintaining blood pH within a very narrow range?
    What effect does it have on cell function and why?
    • Any change in pH can have damaging effects on cell structures and cell functions
    • Can damage cell proteins
    • Low pH = cell death
  5. Bicarbonate-Carbon Dioxide buffer system
    CO2 + H2O <--> H2CO3 <--> H+ + HCO3-
  6. Review factors affecting the oxyhemoglobin curve. (p.3)
    Image Upload 2
    • Relationship between hemoglobin saturation and pO2.
    • pO2:
    • = major factor determining how much oxygen is available for hemoglobin to carry
    • = greater pO2 = more Hgb saturated with O2
    • = lower pO2 = less Hgb saturated
  7. What factors cause shift to the RIGHT on the oxyhemoglobin curve?
    • decreased affinity of O2 for hemoglobin
    • 1) decreased pH
    • 2) increased 2,3 DPG
    • 3) increased temperature
  8. Shift to the RIGHT - decreased pH
    • blood is acidic
    • increased CO and H+ alters hemoglobin configuration
    • reduces O2 binding to heme on Hgb
    • Net effect = hemoglobin releases O2
  9. Shift to the RIGHT - increased 2,3 DPG
    • found in RBCs
    • helps unload O2
    • binds with hemoglobin, releasing O2
    • seen with:
    • = increased metabolism
    • = hypoxia
    • = anemia
  10. Shift to the RIGHT - increased temperature
    increased metabolic state
  11. What factors cause shift to the LEFT on the oxyhemoglobin curve?
    • increased affinity of O2 for hemoglobin
    • 1) increased pH
    • 2) carbon monoxide
    • 3) decreased 2,3 DPG
    • 4) glycosylated hemoglobin (HgbA1c)
  12. Shift to the LEFT - increased pH
    • hemoglobin holds on to O2
    • can cause:
    • = respiratory distress
    • = tissue hypoxia - if hemoglobin does not release O2, O2 is not available to cells
    • = compensatory hyperventilation
  13. Shift to the LEFT - carbon monoxide
    • has 215 times the affinity that O2 has for hemoglobin
    • CO combines with same amount of Hgb as O2 when CO partial pressure is 215 times lower
    • if Hgb exposed to small amounts of CO, unable to carry O2
    • pO2 may appear normal
    • Hgb-O2 content drastically reduced = cell hypoxia
  14. Shift to the LEFT - decreased 2,3 DPG
    • example = blood transfusion
    • due to transfusion, blood is depleted of 2,3 DPG
  15. Shift to the LEFT - glycosylated hemoglobin (HgbA1c)
    • measure and monitor of diabetes
    • increased blood glucose = more glucose in RBCs and binds with hemoglobin causing it to hold on to O2
  16. What effect would these shifts have on affinity of hemoglobin for oxygen?
    • RIGHT = decreased affinity of O2 for Hgb
    • LEFT = increased affinity of O2 for Hgb
  17. What effect does lactic acidosis have on the oxyhemoglobin curve?
    • decreased pH = RIGHT
    • decreased 2,3 DPG = LEFT
    • end result = normal curve
Author
cgordon05
ID
17599
Card Set
Patho 3
Description
Respiratory Acid Base
Updated