What distinguishes lactated ringers from normal saline?

Lactated Ringer's solution is distinguished from normal saline primarily due to its composition, which includes electrolytes such as sodium, potassium, calcium, and lactate, the latter acting as a buffer. This unique combination allows Lactated Ringer's to not only replenish fluids but also to provide essential electrolytes that help maintain acid-base balance in the body. The lactate in the solution can be metabolized to bicarbonate, thus helping to correct metabolic acidosis.

In contrast, normal saline is composed solely of sodium chloride and water, providing a simple isotonic solution without additional electrolytes or buffering capacity. This makes it suitable for hydration and certain medical scenarios, but it does not assist with electrolyte replacement or acid-base balance like Lactated Ringer's does.

The other choices reflect inaccuracies about the characteristics of these solutions. Normal saline is isotonic, containing 0.9% sodium chloride, and can be used for various purposes in clinical settings. Additionally, while Lactated Ringer's is primarily administered intravenously, it is important to recognize that its use is not limited to that route alone in all contexts.