SickKids study finds isotonic IV maintenance fluids safe in general paediatric population

By Rebecca Alberico

At one point or another, almost all hospitalized children will require an intravenous (IV) line as part of their treatment. The exact type of IV fluid that is safest to give to children dependent on these fluids is still a matter of much debate.

Dr. Jeremy Friedman, Associate Paediatrician-in-Chief, and colleagues at The Hospital for Sick Children (SickKids) performed a randomized controlled trial to compare the two most common types of IV fluids in North America – 0.9 per cent NaCl . D5W (isotonic normal saline) versus 0.45 per cent NaCl . D5W (hypotonic half normal saline).

There are concerns that the use of hypotonic IV fluid may be associated with an increased risk of low blood sodium (hyponatremia) that results in morbidity and even mortality in children. However, some physicians are reluctant to use isotonic fluid, worried it will cause problems with high blood sodium (hypernatremia), blood pressure and fluid retention. 

Results showed there was no significant difference in mean serum sodium levels at 24 and 48 hours between those administered isotonic or hypotonic IV maintenance fluids. The results support the notion that isotonic (0.9 per centNaCl) maintenance IV fluid administration is safe in general paediatric patients and may result in fewer cases of hyponatremia. There was no difference between the groups in terms of developing significant problems with high sodium or high blood pressure. However, two patients who were given the hypotonic fluid had to be withdrawn from the trial after 24 hours due to low blood sodium. Friedman anticipates that the patients’ levels could have potentially dropped even further had they not been removed from the trial.

Friedman hopes this trial is used as a guide, rather than a black and white solution, as IV fluids should not take a “one size fits all” approach. He believes the correct choice will be dependent on a number of factors.

“Paediatricians should approach prescribing IV fluids in the same way they would approach prescribing their patients medication, it shouldn’t be any different,” said Friedman. “The sodium content, the rate of the infusion, and the regularity of monitoring the child’s blood sodium are all factors that should be considered daily by the responsible team.”

This is the first trial looking exclusively at a population of non-surgical, non-ICU general paediatric patients. The trial involved 110 children at SickKids from 2008 to2012.

The study has been published in JAMA Pediatrics online and will also appear in the May print issue of the journal.