Which solution is considered unbalanced?

Normal saline is considered an unbalanced solution because it does not contain any electrolytes or buffers that match the typical plasma composition in the body. Normal saline consists solely of sodium chloride in water, providing a solution that only has sodium and chloride ions. This lack of additional electrolytes and the absence of buffers means it can potentially lead to an electrolyte imbalance when used for prolonged periods or in certain clinical situations.

In contrast, Lactated Ringer's solution and Plasma-lyte are balanced solutions, as they contain multiple electrolytes and closely resemble plasma composition. 5% dextrose, although primarily a carbohydrate solution, provides some fluid and can be used in specific scenarios but is not primarily focused on electrolyte balance.

Using normal saline as a rehydration fluid or for fluid replacement in patients requires careful monitoring of electrolytes to avoid complications.