From the Guidelines
Sodium bicarbonate (NaHCO3) should not be used in the treatment of hypernatremia as it can worsen the condition by increasing sodium levels. Hypernatremia is a condition characterized by elevated sodium levels in the blood (>145 mEq/L), and sodium bicarbonate would exacerbate this condition since it contains sodium 1. The primary treatment for hypernatremia involves addressing the underlying water deficit through controlled administration of hypotonic fluids such as 5% dextrose in water or half-normal saline (0.45% NaCl).
Some key points to consider in the treatment of hypernatremia include:
- Gradually reducing serum sodium levels at a safe rate (typically no faster than 8-10 mEq/L per 24 hours) to prevent cerebral edema and neurological complications
- Assessing the patient's volume status (hypovolemic, euvolemic, or hypervolemic hypernatremia) to guide treatment
- Avoiding the use of sodium-containing solutions, such as sodium bicarbonate, which can worsen hypernatremia 1
It's also important to note that sodium bicarbonate is used for treating metabolic acidosis, not hypernatremia, as it would contribute additional sodium to an already sodium-overloaded system. If a patient has both hypernatremia and metabolic acidosis, other approaches to correct the acid-base disturbance would be preferred, such as using alternative buffers or addressing the underlying cause of the acidosis.
From the FDA Drug Label
ADVERSE REACTIONS Overly aggressive therapy with Sodium Bicarbonate Injection, USP can result in metabolic alkalosis (associated with muscular twitchings, irritability, and tetany) and hypernatremia. The FDA drug label does not answer the question.
From the Research
Treatment of Hypernatremia
- Hypernatremia is a potentially life-threatening electrolyte abnormality that can be caused by loss of water or gain of sodium chloride 2.
- Treatment of hypernatremia starts with addressing the underlying etiology and correcting the fluid deficit 3.
- When sodium is severely elevated, patients are symptomatic, or intravenous fluids are required, hypotonic fluid replacement is necessary 3.
Role of Sodium Bicarbonate
- There is no direct evidence to suggest that sodium bicarbonate (NaHCO3) is used in the treatment of hypernatremia 3, 2, 4, 5, 6.
- However, sodium bicarbonate can cause electrolyte abnormalities such as hypokalaemia and hypocalcaemia, leading to QT interval prolongation and torsade de pointes in poisonings with drugs that have mixed sodium and potassium cardiac channel properties 5.
- Excessive doses of hypertonic sodium bicarbonate can cause hypernatremia, fluid overload, metabolic alkalosis, and cerebral oedema in many patients and potentially be lethal 5.
Treatment Approaches
- Individualized rapid infusion of dextrose-based solutions is a commonly adopted fluid therapy for treating acute hypernatremia caused by sodium overload 6.
- Hemodialysis can also be used for patients already treated with hemodialysis 6.
- The correction rates are more rapid in successfully treated patients than in fatal patients, with successfully treated patients typically achieving [Na] ≤160 within 8 hours, [Na] ≤150 within 24 hours, and [Na] ≤145 within 48 hours 6.