Fluids, Electrolytes, and Acid-Base Imbalances Flashcards

Comprehensive vocabulary flashcards covering fluid compartments, electrolyte imbalances (sodium, potassium, magnesium, calcium), intravenous solutions, and acid-base disturbances based on the lecture material.

Intracellular Fluid (ICF)

Fluid located inside body cells, accounting for approximately $67\%$ of total body water (or $40\%$ of total body weight).

Interstitial Fluid (IF)

Extravascular fluid occupying the space between cells, representing approximately $25\%$ of total body water.

Hypotonic Fluid Loss

Fluid loss characterized by a greater loss of sodium/salt relative to water.

Hypertonic Fluid Loss

Fluid loss characterized by a greater loss of water relative to salt, such as during fever accompanied by perspiration.

Isotonic Fluid Loss

Balanced loss of both water and sodium from the extracellular compartment, common in conditions like diarrhea or vomiting.

Insensible Water Loss

Unnoticeable fluid loss through vaporization from the lungs and skin, typically averaging $0.9\,\text{L/day}$.

Sodium ($\text{Na}^+$)

The principal positively charged electrolyte (cation) in extracellular fluid, with a normal concentration of $135\text{ to }145\,\text{mmol/L}$.

Hyponatremia

A serum sodium level lower than $135\,\text{mmol/L}$, which can cause confusion, lethargy, stomach cramps, hypotension, and seizures.

Hypernatremia

A serum sodium level greater than $145\,\text{mmol/L}$, leading to water retention, hypertension, red flushed skin, dry mucous membranes, and intense thirst.

Potassium ($\text{K}^+$)

The most abundant cationic electrolyte inside cells ($95\%$ intracellular), maintaining a normal extracellular range of $3.5\text{ to }5\,\text{mmol/L}$.

Hypokalemia

A serum potassium level below $3.5\,\text{mmol/L}$, causing early symptoms like anorexia, hypotension, lethargy, and late complications like cardiac dysrhythmias.

Hyperkalemia

An abnormally high serum potassium level above $5\,\text{mmol/L}$, resulting in muscle weakness, paresthesia, paralysis, and cardiac rhythm irregularities.

Magnesium ($\text{Mg}^{2+}$)

The second most abundant intracellular cation, with a normal range of $0.65\text{ to }1.05\,\text{mmol/L}$, essential for neuromuscular and cardiac functioning.

Hypomagnesemia

A serum magnesium level under $0.65\,\text{mmol/L}$, manifesting with hyperactive deep tendon reflexes, tremors, Chvostek's sign, Trousseau's sign, and cardiac dysrhythmias.

Hypermagnesemia

A serum magnesium level exceeding $1.05\,\text{mmol/L}$, causing loss of deep tendon reflexes, facial flushing, hypotension, muscle paralysis, and potential respiratory arrest.

Calcium ($\text{Ca}^{2+}$)

An essential mineral with normal total serum levels of $2.10\text{ to }2.50\,\text{mmol/L}$, critical for nerve impulses, muscle contractions, blood clotting, and tooth/bone formation.

Hypocalcemia

A serum total calcium concentration below $2.10\,\text{mmol/L}$, characterized by tetany, tingling around the mouth, seizures, Chvostek's sign, and Trousseau's sign.

Hypercalcemia

A serum total calcium concentration above $2.50\,\text{mmol/L}$, leading to decreased memory, confusion, disorientation, fatigue, and constipation.

Chvostek's and Trousseau's Signs

Clinical signs of latent tetany caused by hypocalcemia or hypomagnesemia; Chvostek's sign involves facial muscle twitching when tapped (A), and Trousseau's sign involves carpopedal spasm induced by a blood pressure cuff (B, C).

First Spacing

The normal, physiological distribution of fluid in the intracellular fluid (ICF) and extracellular fluid (ECF) compartments.

Second Spacing

An abnormal accumulation of interstitial fluid, clinically recognized as edema.

Third Spacing

The accumulation of body fluid in a compartment or space (such as the peritoneal cavity) from which it is not easily exchanged with extracellular fluid.

Crystalloids

Intravenous solutions containing fluid and electrolytes normally present in the body (without proteins), used primarily for fluid replacement and electrolyte regulation.

Colloids

Intravenous solutions containing large protein or polysaccharide molecules (e.g., albumin) that expand intravascular volume by drawing fluid from interstitial spaces.

Blood Products

Intravenous fluids consisting of whole blood or components (e.g., RBCs, plasma) that carry oxygen, expand plasma volume, and correct clotting deficiencies.

Normal Blood pH

The standard arterial blood pH reference range of $7.35\text{ to }7.45$, reflecting hydrogen ion concentration.

Respiratory Acidosis

An acid-base imbalance defined by a blood pH less than $7.35$ and a $\text{PaCO}_2$ greater than $45\,\text{mmHg}$, resulting from hypoventilation.

Respiratory Alkalosis

An acid-base imbalance defined by a blood pH greater than $7.45$ and a $\text{PaCO}_2$ less than $35\,\text{mmHg}$, resulting from hyperventilation.

Metabolic Acidosis

An acid-base disturbance defined by a blood pH less than $7.35$ and a serum bicarbonate ($\text{HCO}_3^-$) level less than $22\,\text{mmol/L}$.

Metabolic Alkalosis

An acid-base disturbance defined by a blood pH greater than $7.45$ and a serum bicarbonate ($\text{HCO}_3^-$) level greater than $26\,\text{mmol/L}$.

ROME Mnemonic

A rule of thumb for ABG analysis: Respiratory Opposite (pH and $\text{PaCO}_2$ move in opposite directions) and Metabolic Equal (pH and $\text{HCO}_3^-$ move in the same direction).

Kussmaul's Respirations

Deep, rapid breathing pattern utilized by the lungs as a compensatory mechanism during metabolic acidosis.

Sodium Polystyrene Sulphonate (Kayexalate®)

A resin medication used in severe hyperkalemia to bind and excrete excess potassium through the gastrointestinal tract.