Intravenous sodium bicarbonate

Intravenous sodium bicarbonate

Clinical data
Pregnancy category	US: C (Risk not ruled out)
Legal status	US: ℞-only
Routes of administration	intravenous
Pharmacokinetic data
Bioavailability	100% (intravenous)
Chemical data
Formula	CHNaO3
Molecular mass	84.01 g/mol
NY (what is this?)  (verify)

Intravenous sodium bicarbonate (trade names including Baros) is a solution for intravenous administration that increases plasma bicarbonate, buffers excess hydrogen ion concentration, raises blood pH and reverses the clinical manifestations of acidosis.

Composition

It is administered as a hypertonic solution of sodium bicarbonate, most commonly in concentrations of 4.2%, 5.0%, 7.5% or 8.4%.

The solutions generally contain no antimicrobial agent or other added buffer.

Mechanism of action

After injection, intravenous sodium bicarbonate dissociates to provide sodium (Na⁺) and bicarbonate (HCO₃⁻) anions. Bicarbonate anions can consume hydrogen ions (H⁺) and thereby be converted to carbonic acid (H₂CO₃), which can subsequently be converted to water (H₂O) and carbon dioxide (CO₂) which can be excreted by the lungs.

Indications

Intravenous sodium bicarbonate is indicated in the treatment of metabolic acidosis, such as can occur in, for example, severe renal disease, diabetic ketoacidosis, circulatory insufficiency, extracorporeal circulation of blood, in hemolysis requiring alkalinization of the urine to avoid nephrotoxicity of blood pigments, and certain drug intoxications, such as by barbiturate overdose, salicylate poisoning, tricyclic antidepressant overdose or methanol poisoning. In addition, sodium bicarbonate is indicated in severe diarrhea, where large amounts of bicarbonate may be lost. However, overall treatment should also strive to treat the underlying cause of the acidosis, such as giving insulin in case of diabetic ketoacidosis.

Precautions

Contraindications

Intravenous sodium bicarbonate is contraindicated in patients who are losing chloride, such as by vomiting.

Because of its sodium content, intravenous sodium bicarbonate should be used with great care, if at all, in patients with congestive heart failure and severe renal insufficiency, where low sodium intake is strongly indicated to prevent sodium retention. By similar rationale, intravenous sodium bicarbonate should be given with caution to patients receiving corticosteroids.

Overdosing

Overdose of intravenous sodium bicarbonate results in solute and/or fluid overload, potentially leading to edema, including pulmonary edema. Also, it can cause metabolic alkalosis (with signs including muscular twitchings, irritability and tetany). Hypernatremia is also possible. Repeated fractional doses and frequent monitoring by laboratory tests are recommended to minimize the possibility of overdosing.

Rapid administration (equal to or exceeding 10 mL/min) of intravenous sodium bicarbonate into neonates and children under two years of age may produce hypernatremia, resulting in a decrease in cerebrospinal fluid pressure and, possibly, intracranial hemorrhage. Therefore, the rate of administration to such patients should not exceed 8 mEq/kg/day, unless a very strong indication is present.

Interactions

Norepinephrine and dobutamine cannot be used as additives in an intravenous sodium bicarbonate solution.

Intravenous sodium bicarbonate should not be mixed with calcium, as they may precipitate, except where compatibility has been previously established for the preparations at hand.

Other adverse reactions

Extravasation of intravenous sodium bicarbonate has been reported to cause chemical cellulitis because of its alkalinity, resulting in tissue necrosis, ulceration and/or sloughing at the site of infiltration. This condition is managed by prompt elevation of the part, warmth and local injection of lidocaine or hyaluronidase.

External links

• Intravenous sodium bicarbonate at Drugs.com, with more detailed dosages