• Normal saline is 0.9% saline. This means that there is 0.9 G of salt (NaCl) per 100 ml of solution, or 9 G per liter.

• This solution has 154 mEq of Na per liter. In fact, all the other solutions listed on the previous screen will be compared to normal saline as if it has 150 mEq of Na/L.

• This solution is used for correction of hypovolemia.

• This solution is used for maintenance IV fluids in all pediatric patients greater than 1 month old due to the risk of hyponatremia with hypotonic IV fluids.

• Useful hint: if you ever have to convert grams of salt (NaCl) into mEq of Na, just remember normal saline: 9G of salt = 154 mEq of Na. You can apply this conversion factor to any other amount.

You will notice that all solutions that have less salt than normal saline have 5% dextrose added to them. There are two reasons for this:

• Normal saline has an osmolality close to that of plasma. Any solution that has less salt will be hypo-osmolar. Rapid infusion of a hypo-osmolar solution can cause osmotically induced water shift into the cells, and this can lead to detrimental effects such as hemolysis. Addition of 5% dextrose ensures that the infused solution will have an osmolality equal to or higher than plasma regardless of the salt concentration.

• A 5% dextrose solution provides at least some calories to a person who might have no other nutritional intake and will reduce catabolism.

Ringer's lactate (LR) is a composite fluid that is available with and without dextrose.

The lactate is metabolized in the liver to bicarbonate. LR provides a source of base, as well as some Ca.

LR is not often used by pediatricians in the US.