(Hypo/Hyper)volemia & (Hypo/Hyper)natremia

Hypovolemia

  • Definition: A condition characterized by a decreased volume of blood plasma.

  • Causes: Blood loss (hemorrhage), dehydration, excessive sweating, diuretics, and severe burns.

  • Symptoms: Dizziness, low blood pressure, increased heart rate, weakness, confusion, and pale skin.

  • Levels: Decreased blood volume, typically indicated by a hematocrit greater than 45% in males, 42% in females.

  • Treatment: Fluid resuscitation with isotonic solutions (e.g., normal saline), addressing the underlying cause, transfusions if necessary.

Hypervolemia

  • Definition: A condition where there is an excess of blood plasma volume.

  • Causes: Heart failure, kidney failure, excessive fluid intake, medications (like corticosteroids), and cirrhosis.

  • Symptoms: Swelling (edema), shortness of breath, increased blood pressure, rapid weight gain, and distended neck veins.

  • Levels: Increased blood volume indicated by lower hematocrit levels, elevated central venous pressure (CVP).

  • Treatment: Diuretics, fluid restriction, and addressing the underlying medical condition such as adjusting medications.

Hyponatremia

  • Definition: A condition with low sodium levels in the blood (below 135 mEq/L).

  • Causes: Excessive fluid intake, kidney problems, certain medications, syndromes causing excessive secretion of antidiuretic hormone (ADH), and heart failure.

  • Symptoms: Nausea, headache, confusion, seizures, coma, and muscle cramps.

  • Levels: Serum sodium levels below 135 mEq/L, severe cases manifesting under 120 mEq/L.

  • Treatment: Sodium supplementation, fluid restriction, careful monitoring of serum sodium levels, and treating underlying conditions.

Hypernatremia

  • Definition: A condition characterized by high sodium levels in the blood (above 145 mEq/L).

  • Causes: Inadequate fluid intake, excessive sweating, diabetes insipidus, high-salt diets, and renal failure.

  • Symptoms: Thirst, confusion, muscle twitching, seizures, dry mucous membranes, and lethargy.

  • Levels: Serum sodium levels above 145 mEq/L, a critical level can be above 160 mEq/L.

  • Treatment: Gradual hydration with isotonic or hypotonic fluids, addressing the underlying cause, and monitoring serum sodium levels closely to ensure proper correction.