Isotonic Intravenous Fluids and Blood Pressure in Pediatric Patients

Abstract

The standard of care for pediatric intravenous (IV) fluids was previously hypotonic IV fluids as maintenance therapy. Following evidence showing hypotonic fluids leading to an increased risk of iatrogenic hyponatremia, isotonic IV fluids have become the current standard of care maintenance fluids. This study examines the safety of administering isotonic IV fluids for constipation by comparing incidences of iatrogenic high blood pressure in pediatric patients with constipation receiving isotonic vs hypotonic fluids. This pre-post study examines the records of children aged 1 to 5 years diagnosed with constipation and admitted to Phoenix Children’s Hospital during July 1, 2009 to June 30th 2012 and July 1st 2013 to June 30th 2016 who received hypotonic and isotonic fluids, respectively, according to standard of care protocols. The primary outcome was the proportion of patients developing high blood pressure after receiving IV fluids for at least 24 hours. Blood pressures were collected on admission (baseline), 24 hours, 48 hours, 72 hours, 96 hours, and 120 hours after hospitalization. Incidences of elevated blood pressure were calculated at baseline, 24 hours, 48 hours, 72 hours, 96 hours, and 120 hours after hospitalization for both groups. When compared to baseline, the isotonic group was not more likely to develop high blood pressure than the hypotonic group at all time points (p value > 0.05). There is no significant increase in rates of high blood pressure in pediatric patients receiving isotonic IV fluids compared to patients receiving hypotonic IV fluids. This supports the current guidelines for using isotonic IV fluids in pediatric patients as maintenance fluids.