Risk factors for hyponatremia after hypotonic fluid infusion

Area of Science:

• Pediatric Medicine
• Clinical Chemistry
• Fluid and Electrolyte Balance

Background:

• Hypotonic intravenous fluids (IVF) increase hyponatremia risk compared to isotonic IVF.
• Isotonic maintenance IVF can lead to excessive sodium (Na) load in children.
• This study investigates hyponatremia incidence and risk factors with varying hypotonic IVF compositions and rates.

Purpose of the Study:

• To analyze the incidence of hyponatremia in pediatric patients receiving hypotonic maintenance IVF.
• To identify independent risk factors for developing hyponatremia under different IVF regimens.
• To compare hyponatremia rates between hypotonic IVF with 35 mmol/L Na at 100% maintenance and 84 mmol/L Na at 70% maintenance.

Main Methods:

• Retrospective analysis of medical charts for children aged 3 months to 15 years.
• Patients were normonatremic before receiving IVF.
• Two groups received IVF: 35 mmol/L Na at 100% maintenance (Na 35) or 84 mmol/L Na at 70% maintenance (Na 84) for 24-48 hours.

Main Results:

• Hyponatremia (Na <135 mmol/L) occurred in 17% (46/275) of children on Na 35 vs. 9% (16/188) on Na 84 (P = 0.01).
• Independent risk factors for hyponatremia included Na 35 (OR, 2.19), low clinical dehydration scale (CDS) score (OR, 0.17), and high body temperature post-IVF (OR, 2.39).
• Multivariate logistic regression identified these factors significantly associated with hyponatremia development.

Conclusions:

• Maintenance IVF with low Na concentration (35 mmol/L) at a 100% rate is an independent risk factor for hyponatremia.
• Low CDS score before IVF and elevated body temperature post-IVF are also independent risk factors for hyponatremia.
• These findings highlight the importance of careful fluid management and monitoring in pediatric patients to prevent hyponatremia.