Intravenous infusion therapy recently has a significant upward trend. Recommendations of M.A. Holliday, W.E. Segar included in the basis of fluid therapy led to predominant use of hypotonic solutions. Hyponatremia, which often develops in children and has a number of serious complications, was caused mainly by using them. To prevent the development of acute hyponatremia, it was recommended intravenous administration of 0.9% NaCl solution. However, acid-base di­sorders due to the development of hyperchloremic acidosis limit its use. In recent years, there are created and actively used solutions that not only help to correct fluid balance, electrolyte disorders, acid-base status, but also have organ-protective effect, which is certainly very important. Therefore, the use of balanced salt solutions as isotonic fluid of choice should take precedence over the introduction of 0.9% saline. The objective of this review — to provide a summary of the current concept of intravenous fluid administration in pediatric intensive care units. Certain tenets to be followed, when prescribing intravenous fluid to a child, are presented. We describe certain advantages and disadvantages of salt solutions, which are used in children. 0.9% NaCl solution is mainly compared with a ba­lanced isotonic saline sterofundin, which has a concentration of sodium 140 mmol/l and significantly lower chloride concentration — 127 mmol/l, as well as potassium, magnesium that is more close to the composition of plasma. The review contains data on lactated Ringer’s solution, which has a somewhat lower concentration of sodium (131 mmol/l) compared to a normal saline and sterofundin. The low concentration of sodium and lactate content somewhat limit its use, especially in neurosurgical pathologies.