What is the electrolyte content of half normal saline (0.45% sodium chloride)?

What is the electrolyte content of half normal saline (0.45% sodium chloride)?

• A. Sodium 154 mEq/L and chloride 154 mEq/L
• B. Sodium 130 mEq/L and chloride 109 mEq/L
• C. Sodium 77 mEq/L and chloride 77 mEq/L
• D. Glucose 50 g/L; Sodium 77 mEq/L; Chloride 77 mEq/L

Answer: (C)

Half-strength saline provides about half the ion content of normal saline, because it is 0.45% NaCl instead of 0.9%. Normal saline has roughly 154 mEq/L of sodium and 154 mEq/L of chloride. Halving those values gives about 77 mEq/L of sodium and 77 mEq/L of chloride. So the electrolyte content is about 77 mEq/L Na and 77 mEq/L Cl. If a dextrose-containing version is used (for example, a glucose-containing half-strength solution), the Na and Cl values remain the same, while glucose adds calories but does not change the electrolyte concentrations.

Half-strength saline provides about half the ion content of normal saline, because it is 0.45% NaCl instead of 0.9%. Normal saline has roughly 154 mEq/L of sodium and 154 mEq/L of chloride. Halving those values gives about 77 mEq/L of sodium and 77 mEq/L of chloride. So the electrolyte content is about 77 mEq/L Na and 77 mEq/L Cl. If a dextrose-containing version is used (for example, a glucose-containing half-strength solution), the Na and Cl values remain the same, while glucose adds calories but does not change the electrolyte concentrations.