Low plasma Na+ (sodium ion) concentrations is referred to as:
A hypernatremia
B hyponatremia
C hyperkalemia
D hypokalemia
The correct answer and explanation is:
The correct answer is B. Hyponatremia.
Hyponatremia is a condition characterized by low sodium ion (Na+) concentrations in the plasma. Sodium is a crucial electrolyte in the body, primarily responsible for regulating fluid balance, blood pressure, and nerve function. Normal plasma sodium levels typically range from 135 to 145 milliequivalents per liter (mEq/L). When sodium levels fall below this range, it can lead to various symptoms and complications.
Several factors can contribute to hyponatremia. It may result from excessive water retention, which dilutes sodium in the bloodstream, as seen in conditions like Syndrome of Inappropriate Antidiuretic Hormone (SIADH) or heart failure. Another cause is an inadequate intake of sodium, which can occur during prolonged physical activity in hot environments without sufficient salt replacement, leading to exercise-associated hyponatremia. Additionally, certain medications like diuretics, which increase urine production, can lead to a loss of sodium.
Symptoms of hyponatremia vary depending on the severity and rate of onset. Mild hyponatremia may cause nausea, headache, and fatigue, while more severe cases can result in confusion, seizures, and coma. In extreme cases, hyponatremia can be life-threatening if left untreated.
Management of hyponatremia depends on its underlying cause. Treatment may involve fluid restriction, sodium replacement through oral or intravenous administration, or addressing any underlying medical conditions that contribute to the low sodium levels. Careful monitoring is essential to avoid rapid correction of sodium levels, as too fast of a correction can lead to dangerous complications like central pontine myelinolysis.
In contrast, hypernatremia (A) refers to high sodium levels, hyperkalemia (C) refers to high potassium levels, and hypokalemia (D) refers to low potassium levels.