preparing isotonic solution

Q: Which of the solutions will produce a nearly isotonic solution? - select one

A) 3 amps of NaHCO3 in 1 L of D-5 W

B) 3 amps of NaHCO3 in 1 L of 0.45 NS

Answer: A

Adding three ampules of sodium bicarbonate, each containing 50 mEq of sodium and 50 mL of water, to one liter of 5% dextrose in water, produces a nearly isotonic solution with a sodium concentration of approximately 130 mEq/L. 

Adding the same three ampules of sodium bicarbonate to one liter of half isotonic saline (0.45%), which contains about 77 mEq/L of sodium, will produce a highly hypertonic solution with a sodium concentration of 197 mEq/L!

The objective of this question is to enhance the understanding that a simple mistake in an order can be fatal!

#electrolytes

#acidosis

Further readings:

1. Adeva-Andany MM, Fernández-Fernández C, Mouriño-Bayolo D, Castro-Quintela E, Domínguez-Montero A. Sodium bicarbonate therapy in patients with metabolic acidosis. ScientificWorldJournal. 2014;2014:627673. doi: 10.1155/2014/627673. Epub 2014 Oct 21. PMID: 25405229; PMCID: PMC4227445.

2. Zhang Z, Zhu C, Mo L, Hong Y. Effectiveness of sodium bicarbonate infusion on mortality in septic patients with metabolic acidosis. Intensive Care Med. 2018 Nov;44(11):1888-1895. doi: 10.1007/s00134-018-5379-2. Epub 2018 Sep 25. PMID: 30255318.

3. Sepúlveda RA, Juanet C, Sharp J, Kattan E. Bicarbonato de sodio intravenoso ¿Cuándo, cómo y por qué utilizarlo? [Intravenous sodium bicarbonate. When, how and why to use it?]. Rev Med Chil. 2022 Sep;150(9):1214-1223. Spanish. doi: 10.4067/S0034-98872022000901214. PMID: 37358132.