Fluids, Electrolytes, Acids, and Bases

Vocabulary flashcards covering body fluid compartments, electrolyte balances, disorders, calcium homeostasis, and acid-base balance based on the lecture notes.

Extracellular Fluid (ECF)

Body fluids located outside of cells, comprising interstitial fluid that fills spaces between most body cells and intravascular fluid (plasma).

Intracellular Fluid (ICF)

Liquid contained within cell membranes, accounting for approximately $25\,\text{L}$ or $40\%$ of total body weight.

Body Fluid Compartments

The distribution of total body water ($40\,\text{L}$, $60\%$ body weight) into intracellular fluid ($25\,\text{L}$, $40\%$ body weight) and extracellular fluid ($15\,\text{L}$, $20\%$ body weight), which further divides into interstitial fluid ($12\,\text{L}$, $80\%$ of ECF) and plasma ($3\,\text{L}$, $20\%$ of ECF).

Electrolytes

Elements that carry an electrical current when dissolved, having greater osmotic power than nonelectrolytes, and playing essential roles in neuromuscular function and acid-base balance.

Nonelectrolytes

Molecules in body fluids that do not carry an electrical charge when dissolved, such as glucose, lipids, creatinine, urea, and most proteins.

Albumin

A protein produced by the liver that circulates in the bloodstream to carry vitamins and enzymes while exerting osmotic pressure to prevent fluid from leaking out of capillaries.

Dehydration

A water balance disorder where water loss exceeds water intake, caused by hemorrhage, severe burns, prolonged vomiting or diarrhea, profuse sweating, water deprivation, or diuretic abuse.

Renin-Angiotensin-Aldosterone System

A hormonal path activated during dehydration by reduced blood pressure and decreased kidney blood flow, increasing sodium retention in the kidneys so water can follow.

Hypotonic Hydration

A water balance disorder resulting from water intoxication or kidney dysfunction in which ECF is diluted while sodium content remains normal, causing water to flow into cells.

Edema

An atypical accumulation of fluid in the interstitial space leading to tissue swelling, caused by factors that increase fluid flow out of the bloodstream or prevent its return.

Pulmonary Edema

A pathological condition characterized by fluid build-up in the alveoli and fluid leakage into the lungs, impairing normal gas exchange.

Hyponatremia

The most common electrolyte imbalance condition, caused by fluid overload, vomiting, diarrhea, or excessive sweating, presenting with weakness, confusion, convulsions, and coma.

Hypernatremia

A sodium imbalance caused by loss of water without proportional loss of sodium (dehydration), leading to water diffusing out of ICF and symptoms such as thirst, dryness, and wrinkled skin.

Hyperkalemia

An elevated potassium level in the blood, commonly caused by renal failure or massive tissue trauma, which can trigger cardiac arrhythmias and tachycardia.

Hypokalemia

An abnormally low potassium level in the blood, frequently caused by the use of diuretics, leading to muscle weakness and paralysis.

Calcium Homeostasis

The physiological regulation of body calcium involving osteoclast and osteoblast activity in bone, renal reabsorption, and intestinal absorption mediated by PTH, calcitonin, and active vitamin D.

Hypercalcemia

An elevated level of calcium in the blood, which can result from the oversecretion of parathyroid hormone (hyperparathyroidism).

Hypocalcemia

An abnormally low concentration of calcium in the blood, which can result from hypoparathyroidism, vitamin D deficiency, or chronic renal failure.

Acidosis

A condition in which arterial blood pH falls below $7.35$, indicating an abnormally high concentration of hydrogen ions ($\text{H}^+$).

Alkalosis

A condition in which arterial blood pH rises above $7.45$, indicating an abnormally low concentration of hydrogen ions ($\text{H}^+$).

Carbonic Acid-Bicarbonate Buffer System

A critical buffer system represented by $\text{CO}_2 + \text{H}_2\text{O} \rightleftharpoons \text{H}_2\text{CO}_3 \rightleftharpoons \text{H}^+ + \text{HCO}_3^-$, adjusted by the lungs and kidneys to regulate systemic pH.

Respiratory Acidosis

An acid-base disorder defined by an arterial blood pH below $7.35$ and a partial pressure of $\text{CO}_2$ greater than $45\,\text{mmHg}$, caused by hypoventilation, asphyxia, or pneumonia.

Metabolic Acidosis

An acid-base disorder defined by an arterial blood pH below $7.35$ and a bicarbonate concentration less than $20\,\text{mmol/L}$, caused by conditions such as fasting, ketoacidosis, or lactic acidosis.

Respiratory Alkalosis

An acid-base disorder defined by an arterial blood pH above $7.45$ and a partial pressure of $\text{CO}_2$ less than $35\,\text{mmHg}$, typically caused by hyperventilation.

Metabolic Alkalosis

An acid-base disorder defined by an arterial blood pH above $7.45$ and a bicarbonate concentration greater than $27\,\text{mmol/L}$, caused by conditions such as severe vomiting or bulimia.