Chapter 25: Fluid, Electrolyte, and pH Imbalances

These vocabulary flashcards cover fluid imbalances (dehydration, hyperhydration, isosmotic states), electrolyte concentrations for sodium, potassium, and calcium, and the characteristic findings and causes of acid-base disorders.

Dehydration

A fluid imbalance characterized by decreased volume and increased osmolarity, with symptoms beginning with dry mouth and thirst and progressing to dry skin, fever, and impaired organ function.

Oliguria

Decreased urine production; a symptom that occurs as dehydration progresses.

Hyperhydration (Overhydration)

Hypotonic hydration where ECF volume increases and its osmotic pressure falls, causing cells to swell as water enters them by osmosis.

Cerebral Edema

A condition resulting from hyperhydration that can lead to mental status changes, seizures, coma, and death.

Hypervolemia

A type of isosmotic fluid imbalance where ECF volume increases without a significant change in osmotic pressure, often resulting in edema.

Hypovolemia

The loss of ECF volume and electrolytes equally, often caused by blood loss and potentially leading to shock, organ failure, and death.

Hypernatremia

Sodium ion concentrations in the blood greater than $145\,mEq/l$. Common symptoms include low blood pressure, excessive thirst, and fever.

Hyponatremia

Sodium ion concentrations in the blood less than $135\,mEq/l$, which can cause muscle weakness and mental status changes.

Hyperkalemia

Plasma potassium ion concentration above $4.5\,mEq/L$. Main symptoms include muscle cell shut down and instant death.

Hypokalemia

Plasma potassium ion concentration below $3.9\,mEq/L$, often caused by chronic diuretic usage.

Bradycardia

A slowed heart rate which is a characteristic symptom of hypokalemia.

Hypercalcemia

Plasma calcium ion concentration greater than $10.5\,mg/dl$. Symptoms include mental sluggishness, kidney stones, bone pain, and reduced reflex activity.

Hypocalcemia

Plasma calcium ion concentration lower than $8.7\,mg/dl$. It can result in carpopedal spasm, long overly strong cardiac contraction, and dyspnea.

Respiratory acidosis

An acid-base disorder characterized by decreased pH and increased $P_{CO_2}$. Causes include air passage blockages or decreased ventilation from brainstem dysfunction.

Respiratory alkalosis

An acid-base disorder characterized by increased pH and decreased $P_{CO_2}$. Causes include hyperventilation due to psychological states or high altitudes.

Metabolic acidosis

An acid-base disorder characterized by decreased pH and decreased $HCO_3^-$, often caused by prolonged diarrhea or renal failure.

Metabolic alkalosis

An acid-base disorder characterized by increased pH and increased $HCO_3^-$. Causes include prolonged vomiting or the ingestion of large doses of oral antacids.