Fluid, Electrolyte and Acid-Base Imbalances Flashcards

Comprehensive vocabulary flashcards covering fluid compartments, transport mechanisms, electrolyte imbalances (Sodium, Potassium, Calcium, Magnesium, Phosphate, Chloride), and Acid-Base homeostasis including ranges and clinical manifestations.

Intracellular Compartment (ICF)

The fluid compartment located inside the cells.

Extracellular Compartment (ECF)

The fluid compartment consisting of intravascular fluid (IVF), interstitial fluid (ISF), cerebrospinal fluid (CSF), and various transcellular fluids/secretions.

Filtration

The movement of water and solutes from blood to interstitial fluid due to hydrostatic pressure, which acts as a pushing force from high to low pressure areas.

Osmosis

The movement of water from interstitial fluid to blood due to osmotic pressure, which acts as a pulling force from low solute concentration to higher solute concentration areas.

Antidiuretic hormone (ADH)

A hormone responsible for the reabsorption of water from the kidney tubules into the blood.

Aldosterone

A hormone that regulates fluid balance by promoting the reabsorption of sodium and water from the kidney tubules.

Atrial natriuretic peptide (ANP)

A peptide synthesized by myocardial cells that helps regulate fluid, sodium, and potassium levels.

Edema

An excessive amount of fluid in the interstitial compartment, which can cause swelling, impair tissue perfusion, or trap drugs.

Pitting Edema

A condition where fluid in the interstitial space moves aside when pressure is applied, leaving a "pit" or depression when the finger is removed.

Dehydration

A state of insufficient body fluid resulting from inadequate intake, excessive loss, or both, often measured by changes in body weight.

Third-Spacing

A situation where fluid shifts out of the blood into a body cavity or tissue (such as in burns or certain infections) and can no longer reenter the vascular compartment.

Sodium ($Na^+$)

The primary cation in the ECF with a normal range of $135 - 145\,mEq/L$; it is essential for maintenance of extracellular fluid volume.

Hyponatremia

A condition where serum sodium levels are below $135\,mEq/L$, potentially caused by excessive sweating, vomiting, diarrhea, or excessive water intake.

Hypernatremia

A condition where serum sodium levels exceed $145\,mEq/L$, often resulting from ingestion of large amounts of sodium without enough water or loss of the thirst mechanism.

Potassium ($K^+$)

The major intracellular cation with a normal range of $3.5 - 5\,mEq/L$; its levels are heavily influenced by acid-base balance and insulin.

Hypokalemia

A condition where serum potassium is below $3.5\,mEq/L$, often manifesting as cardiac dysrhythmias and flat or inverted T waves on an EKG.

Hyperkalemia

A condition where serum potassium is greater than $5\,mEq/L$, which can lead to tall, peaked T-waves and respiratory or cardiac arrest.

Calcium ($Ca^{2+}$)

An extracellular cation with a normal range of $8.5 - 10.2\,mg/dL$, controlled by parathyroid hormone (PTH) and calcitonin.

Chvostek sign

A manifestation of hypocalcemia characterized by a spasm of the facial muscle when the facial nerve is tapped.

Trousseau sign

A carpopedal spasm that occurs as a manifestation of hypocalcemia when a blood pressure cuff is inflated.

Milk-alkali syndrome

A cause of hypercalcemia associated with increased intake of milk and antacids.

Magnesium ($Mg^{2+}$)

An intracellular ion with a normal range of $0.7 - 1.1\,mmol/L$, approximately $50\%$ of which is stored in bone.

Phosphate ($PO_4^{3-}$)

An ion with a normal range of $0.85 - 1.45\,mmol/L$ that has a reciprocal relationship with calcium and is essential for ATP-requiring metabolic processes.

Chloride ($Cl^-$)

The major extracellular anion with a normal range of $98 - 106\,mmol/L$; its levels are typically related to sodium levels.

Acidosis

A state characterized by an excess of hydrogen ions ($H^+$) and a decrease in serum pH below $7.35$.

Alkalosis

A state characterized by a deficit of hydrogen ions ($H^+$) and an increase in serum pH above $7.45$.

Respiratory Acidosis

An imbalance caused by an increase in $CO_2$ levels, often due to slow, shallow respirations or respiratory congestion.

Metabolic Acidosis

An imbalance resulting from a decrease in bicarbonate ions, frequently caused by shock, diabetic ketoacidosis, or renal failure.

Decompensation

A life-threatening situation that occurs when the causative problem for a pH imbalance worsens or compensation mechanisms fail.