[05] Acid-Base Balance Flashcards
What is the primary function of the respiratory system in maintaining acid-base balance?
To eliminate carbon dioxide, a by-product of cellular metabolism and a weak acid
What is the normal pH range of arterial blood?
7.35 to 7.45
What is the role of carbon dioxide (CO2) in acid-base balance?
CO2 combines with water to form carbonic acid (H2CO3), which then dissociates to produce H+ ions and bicarbonate ions (HCO3-)
What is respiratory acidosis?
A state of increased arterial blood CO2 concentration leading to decreased pH (more acidic)
What are the common causes of respiratory acidosis?
- Hypoventilation
- Lung disease
- Neuromuscular disorders
What is respiratory alkalosis?
A state of decreased arterial blood CO2 concentration leading to increased pH (more basic)
What are the common causes of respiratory alkalosis?
- Hyperventilation
- High altitude
- Pregnancy
- Fever
How does the kidney help in acid-base balance?
By regulating the excretion and reabsorption of bicarbonate ions (HCO3-)
What is metabolic acidosis?
A state of decreased bicarbonate ion concentration leading to decreased blood pH
What are the common causes of metabolic acidosis?
- Diabetic ketoacidosis
- Kidney disease
- Severe diarrhea
What is metabolic alkalosis?
A state of increased bicarbonate ion concentration leading to increased blood pH
What are the common causes of metabolic alkalosis?
- Excessive vomiting
- Diuretics
- Excessive bicarbonate intake
What are the symptoms of acidosis?
- Headache
- Sleepiness
- Confusion
- Loss of consciousness
What are the symptoms of alkalosis?
- Light-headedness
- Numbness
- Nausea
- Muscle twitching
What is the role of buffers in maintaining acid-base balance?
Buffers neutralize excess acids or bases in body fluids to maintain pH within a normal range
What is the most important buffering system in the body?
The bicarbonate buffering system
What is compensation in the context of acid-base balance?
The body’s physiological response to restore normal pH by either increasing/decreasing respiration to adjust CO2 levels (respiratory compensation), or adjusting bicarbonate levels in the kidneys (metabolic compensation)
What is the anion gap?
The difference between primary measured cations (sodium Na+ and potassium K+) and the primary measured anions (chloride Cl- and bicarbonate HCO3-) in serum, plasma, or urine
What is the significance of the anion gap in acid-base balance?
An increased anion gap indicates metabolic acidosis due to the accumulation of unmeasured acids
What is carbonic anhydrase?
An enzyme that catalyzes the reaction between carbon dioxide and water to form carbonic acid
Where is carbonic anhydrase primarily found?
In red blood cells and the kidneys
What is the role of carbonic anhydrase in the respiratory system?
It accelerates the conversion of carbon dioxide and water into carbonic acid, which then dissociates into hydrogen ions and bicarbonate ions
How does carbonic anhydrase contribute to the acid-base balance?
By catalyzing the reaction that forms bicarbonate, a key component in the bicarbonate buffering system
What would happen in the absence of carbonic anhydrase?
The speed of conversion of CO2 to bicarbonate would significantly reduce, negatively affecting acid-base balance
