Control of Plasma pH
1. Regulation by Kidneys and Lungs -
- Kidneys and lungs are crucial in
maintaining plasma pH within normal ranges.
- Kidneys regulate pH through
bicarbonate reabsorption and ammonium ion
generation.
- Lungs adjust pH by controlling
carbon dioxide levels via ventilation.
2. Normal Levels and Pathological
Extremes -
- Blood pH typically stands at 7.4,
with arterial blood slightly higher (7.45) and
venous blood slightly lower (7.35).
- Pathological extremes range from 6.8 to
8.0, leading to acidemia (acidic blood) or alkalemia
(alkaline blood).
3. Sources of Acids -
- Acids come from metabolic
processes such as OXPHOS, glycolysis,
protein breakdown, and fatty acid metabolism.
4. Control Mechanisms -
- Base Loss - Occurs through pancreatic juice, diarrhea, and loss of bicarbonate.
- Base Production/Acid Loss - Involves bicarbonate reabsorption in kidneys,
increased respiration, and vomiting.
- Chemical Buffers -Fast non-volatile buffers like hemoglobin and volatile
buffering with carbon dioxide.
5. Henderson-Hasselbalch Equation
- Relates pH to bicarbonate and PCO2 levels, indicating their role in pH balance.
6. Respiratory Compensation -
- Involves fast mechanisms like hyperventilation or hypoventilation and slow
renal compensation.
7. Types of Acid-Base Disorders -
- Respiratory Acidosis -Decreased pH due to high PCO2.
- Respiratory Alkalosis -Increased pH due to low PCO2.
- Metabolic Acidosis - Decreased pH due to low bicarbonate.
1. Regulation by Kidneys and Lungs -
- Kidneys and lungs are crucial in
maintaining plasma pH within normal ranges.
- Kidneys regulate pH through
bicarbonate reabsorption and ammonium ion
generation.
- Lungs adjust pH by controlling
carbon dioxide levels via ventilation.
2. Normal Levels and Pathological
Extremes -
- Blood pH typically stands at 7.4,
with arterial blood slightly higher (7.45) and
venous blood slightly lower (7.35).
- Pathological extremes range from 6.8 to
8.0, leading to acidemia (acidic blood) or alkalemia
(alkaline blood).
3. Sources of Acids -
- Acids come from metabolic
processes such as OXPHOS, glycolysis,
protein breakdown, and fatty acid metabolism.
4. Control Mechanisms -
- Base Loss - Occurs through pancreatic juice, diarrhea, and loss of bicarbonate.
- Base Production/Acid Loss - Involves bicarbonate reabsorption in kidneys,
increased respiration, and vomiting.
- Chemical Buffers -Fast non-volatile buffers like hemoglobin and volatile
buffering with carbon dioxide.
5. Henderson-Hasselbalch Equation
- Relates pH to bicarbonate and PCO2 levels, indicating their role in pH balance.
6. Respiratory Compensation -
- Involves fast mechanisms like hyperventilation or hypoventilation and slow
renal compensation.
7. Types of Acid-Base Disorders -
- Respiratory Acidosis -Decreased pH due to high PCO2.
- Respiratory Alkalosis -Increased pH due to low PCO2.
- Metabolic Acidosis - Decreased pH due to low bicarbonate.
