Acid-Base Balance Flashcards
What are acids and bases?
Acids
- produced during metabolism (H+ ions)
Bases
- neutralise and promote excretion of acids
What is an acid-base imbalance caused by?
- fluid and electrolyte imbalances
- diabetes mellitus
- kidney disease
- vomiting and diarrhoea
Base is to ______, as acid is to ______.
Base is to acidic, whilst acid is to alkalotic.
What are the three systems that regulate acid-base balance?
- buffer (immediate)
- respiratory (minutes to hours)
- renal (2-3 days)
Explain the buffer system.
Changes strong acids to weak acids, or binds with acids to neutralise their effect. I is very efficient system because the buffer components are readily added or removed from the body.
Explain protein and buffers.
- largest buffer system in the body
- can function as a base or an acid (amphoteric)
- can release or bind H+
- mainly located within the cells
Explain the respiratory system role in acid-base balance.
- lungs excrete CO2 and water to maintain balance
- H+ binds with bicarbonate to form carbonic acid which is then broken down into CO2 and H2O
Explain the renal system role in acid-base balance.
- kidneys reabsorb, conserve and generate bicarbonate
- kidneys excrete excess H+ ions
What is the difference between respiratory and metabolic acidosis?
Respiratory acidosis:
- build up of CO2
- common causes are COPD, sedation overdose, respiratory compromise
- renal compensation
Metabolic acidosis:
- is due to an accumulation of acids or loss of bicarbonate
- commonly caused by diabetic ketoacidosis, starvation, severe diarrhoea, renal failure, shock
- respiratory compensation
Explain the difference between respiratory and metabolic alkalosis.
Respiratory alkalosis:
- increased CO2 excretion
- commonly caused by hyperventilation, stimulation of respiratory centre
Metabolic alkalosis:
- loss of acid or gain in bicarbonate
- commonly caused by severe vomiting, excessive GIT suctioning, diuretic therapy, dietary excess of K+ or sodium bicarbonate
- respiratory compensation
