Fluid and Electrolyte Balance Vocabulary

This flashcard set covers the vocabulary from Chapter 10: Fluid and Electrolytes, including fluid compartments, transport mechanisms, and specific electrolyte and acid-base imbalances with their corresponding laboratory values and clinical meanings.

Homeostasis

The state of internal equilibrium necessary for life.

Intracellular fluid (ICF)

Fluid contained within the cells, comprising approximately $2/3$ of body fluid and primarily found in skeletal muscle mass.

Extracellular fluid (ECF)

Fluid outside the cells, categorized into intravascular (plasma), interstitial (lymph), and transcellular (cerebrospinal, pericardial, synovial) spaces.

Electrolytes

Active chemicals expressed in millequivalents ($mEq$) per liter that carry positive (cations) or negative (anions) electrical charges.

Osmosis

The diffusion of water caused by fluid and solute concentration gradients, moving from an area of low solute concentration to high solute concentration.

Diffusion

The process by which solutes move from an area of higher concentration to one of lower concentration without requiring an expenditure of energy.

Filtration

The movement of water and solutes from an area of high hydrostatic pressure to an area of low hydrostatic pressure.

Active transport

A mechanism, such as the sodium–potassium pump, that uses energy to maintain higher concentrations of extracellular sodium and intracellular potassium.

Hydrostatic pressure

The pressure exerted on the walls of blood vessels that influences the movement of fluid through capillary walls.

Fluid volume deficit (FVD)

Also known as hypovolemia, this occurs when the loss of extracellular fluid exceeds the intake ratio of water and electrolytes are lost in the same proportion as they exist in normal body fluids.

Dehydration

A condition distinct from FVD involving the loss of water alone, resulting in increased serum sodium levels.

Fluid volume excess (FVE)

Also known as hypervolemia, this clinical manifestation is the expansion of the ECF caused by the abnormal retention of water and sodium in the same proportions they normally exist in the ECF.

Hyponatremia

A serum sodium level less than $135\,mEq/L$, which can be acute, chronic, or exercise-associated.

Hypernatremia

A serum sodium level greater than $145\,mEq/L$, often characterized by thirst and elevated temperature.

Hypokalemia

A below-normal serum potassium level of less than $3.5\,mEq/L$, which can lead to ECG changes and dysrhythmias.

Hyperkalemia

A serum potassium level greater than $5.0\,mEq/L$, frequently associated with cardiac arrest and impaired renal function.

Hypocalcemia

A serum calcium level less than $8.6\,mg/dL$, which can cause tetany, Trousseau sign, and Chvostek sign.

Hypercalcemia

A serum calcium level greater than $10.4\,mg/dL$, often caused by malignancy or hyperparathyroidism.

Hypomagnesemia

A serum magnesium level less than $1.8\,mg/dL$, often associated with alcoholism and characterized by neuromuscular irritability.

Hypermagnesemia

A serum magnesium level greater than $2.6\,mg/dL$, which can lead to hypoactive reflexes and depressed respirations.

Hypophosphatemia

A serum phosphorus level below $2.7\,mg/dL$, potentially causing confusion, muscle weakness, and tissue hypoxia.

Hyperphosphatemia

A serum phosphorus level above $4.5\,mg/dL$, often resulting in soft tissue calcifications secondary to hypocalcemia.

Hypochloremia

A serum chloride level less than $97\,mEq/L$, which has an inverse relationship with bicarbonate.

Hyperchloremia

A serum chloride level more than $107\,mEq/L$, usually due to iatrogenically induced metabolic acidosis.

Metabolic Acidosis

A clinical state characterized by a low pH ($< 7.35$) and a low plasma bicarbonate ($< 22\,mEq/L$).

Metabolic Alkalosis

A clinical state characterized by a high pH ($> 7.45$) and a high bicarbonate ($> 26\,mEq/L$), commonly due to vomiting or gastric suction.

Respiratory Acidosis

A clinical state characterized by a low pH ($< 7.35$) and a $PaCO_2 > 42\,mm\,Hg$ due to inadequate ventilation.

Respiratory Alkalosis

A clinical state characterized by a high pH ($> 7.45$) and a $PaCO_2 < 35\,mm\,Hg$ due to hyperventilation.