Acid-Base Imbalances – Vocabulary Flashcards

Vocabulary flashcards covering key terms from the lecture notes on acid-base regulation and imbalance.

pH

Scale used to express hydrogen ion concentration; lower pH means more acidic; normal arterial pH is 7.35–7.45.

Hydrogen ion (H+)

Ion whose concentration determines acidity; increased H+ lowers pH.

Buffer

Molecule that accepts H+ to raise pH; includes bicarbonate (HCO3-) and phosphate (PO4-3).

Bicarbonate ion (HCO3-)

Primary buffer in plasma and urine filtrate; combines with H+ to form carbonic acid.

Phosphate (PO4-3)

Buffer mainly in cytoplasm and urine filtrate.

Carbonic acid (H2CO3)

Weak acid formed when CO2 dissolves in water; dissociates to H+ and HCO3-.

Carbon dioxide (CO2)

Gas that, when dissolved in water, forms carbonic acid and participates in buffering.

Lungs (acid removal system)

Remove or retain CO2; CO2 + H2O ⇄ H2CO3 ⇄ H+ + HCO3-.

Kidneys (acid removal system)

Renal tubules secrete/excrete H+ and regenerate/reabsorb HCO3-.

Metabolic acidosis

Acid-base imbalance from increased non-carbonic acids or renal failure; low pH with compensatory increased respiration.

Metabolic alkalosis

Loss of non-carbonic acids (e.g., vomiting) with renal retention of H+ and excretion of HCO3-; high pH with compensatory decreased respiration.

Respiratory acidosis

CO2 retention due to decreased ventilation; low pH; renal compensation (H+ excretion and HCO3- regeneration) occurs over time.

Respiratory alkalosis

Increased CO2 removal due to hyperventilation; high pH; renal compensation less common and usually limited.

Kussmaul respiration

Deep, labored breathing pattern associated with metabolic acidosis as a compensatory mechanism.

Compensation

Physiologic adjustment by the non-primary system (kidneys or lungs) to counterbalance an acid-base disturbance.

Correction

The primary system self-corrects without requiring compensatory changes (distinct from compensation).

Non-carbonic acids

Acids other than CO2 (e.g., lactic acid, ketones) that can cause metabolic acidosis.

Lactic acid

A non-carbonic acid that can accumulate in metabolic acidosis.

Ketones

Non-carbonic acids produced in disorders like ketoacidosis; contribute to metabolic acidosis.

Hypoventilation

Decreased ventilation leading to CO2 retention and respiratory acidosis.

Hyperventilation

Increased ventilation leading to CO2 removal and respiratory alkalosis.

Respiratory compensation

Renal adjustments (H+ excretion and HCO3- regeneration) in response to metabolic disturbances.

Renal compensation for respiratory disturbances

Kidneys increase or decrease H+ excretion and HCO3- regeneration to balance pH in chronic respiratory disorders.

Normal arterial pH reference

7.35–7.45; values outside this range indicate acidosis or alkalosis.

Acid-base regulation

System of buffers, lungs, and kidneys maintaining pH within a narrow range.