Chapter 26: Fluid, Electrolyte, and Acid-Base Balance

fluid compartment

fluid compartment

a location that is largely separate from another compartment by some form of a physical barrier.

Metabolic Compensation

for respiratory diseases that can create acidosis revolves around the conservation of bicarbonate ions.

Respiratory Compensation

for metabolic acidosis increases the respiratory rate to drive off CO2 and readjust the bicarbonate to carbonic acid ratio to the 20:1 level.

Sodium

the major cation of the extracellular fluid.

Electrolyte Balance

The body contains a large variety of ions, or electrolytes, which perform a variety of functions.

Respiratory alkalosis

occurs when the blood is overly alkaline due to a deficiency in carbonic acid and CO2 levels in the blood.

Respiratory acidosis

occurs when the blood is overly acidic due to an excess of carbonic acid, resulting from too much CO2 in the blood.

Metabolic alkalosis

is the opposite of metabolic acidosis.

Metabolic acidosis

occurs when the blood is too acidic (pH below 7.35) due to too little bicarbonate, a condition called primary bicarbonate deficiency.

Potassium

is the major intracellular cation

Hypernatremia

is an abnormal increase of blood sodium.

Hypocapnia

or abnormally low blood levels of CO2, occurs with any cause of hyperventilation that drives off the CO2, such as salicylate toxicity, elevated room temperatures, fever, or hysteria.

Hypercapnia

or abnormally elevated blood levels of CO2, occurs in any situation that impairs respiratory functions, including pneumonia and congestive heart failure.

Hyperphosphatemia

or abnormally increased levels of phosphates in the blood, occurs if there is decreased renal function or in cases of acute lymphocytic leukemia.

Bicarbonate-Carbonic Acid Buffer

works in a fashion similar to phosphate buffers

Hemoglobin

is the principal protein inside of red blood cells and accounts for one-third of the mass of the cell.

Buffer Systems in the Body

are extremely efficient, and different systems work at different rates.

Angiotensin II

causes vasoconstriction and an increase in systemic blood pressure.

Hypophosphatemia

or abnormally low phosphate blood levels, occurs with heavy use of antacids, during alcohol withdrawal, and during malnourishment.

Hypercalcemia

or abnormally high calcium blood levels, is seen in primary hyperparathyroidism.

Chloride

is the predominant extracellular anion.

Bicarbonate

is the second most abundant anion in the blood.

Hypocalcemia

or abnormally low calcium blood levels, is seen in hypoparathyroidism, which may follow the removal of the thyroid gland, because the four nodules of the parathyroid gland are embedded in it.

Hypochloremia

or lower-than-normal blood chloride levels, can occur because of defective renal tubular absorption.

Hyperkalemia

an elevated potassium blood level, also can impair the function of skeletal muscles, the nervous system, and the heart.

interstitial fluid (IF)

that surrounds all cells not in the blood

intracellular fluid (ICF)

compartment is the system that includes all fluid enclosed in cells by their plasma membranes.

Extracellular fluid (ECF)

surrounds all cells in the body

Hydrostatic pressure

the force exerted by a fluid against a wall, causes movement of fluid between compartments.

Plasma osmolality

is thus the ratio of solutes to water in blood plasma

Antidiuretic hormone (ADH)

also known as vasopressin, controls the amount of water reabsorbed from the collecting ducts and tubules in the kidney.

Hypokalemia

is an abnormally low potassium blood level.

Hyponatremia

is a lower-than-normal concentration of sodium, usually associated with excess water accumulation in the body, which dilutes the sodium.

Hypercalcemia

or abnormally high calcium blood levels, is seen in primary hyperparathyroidism.