Evaluation of sodium deficit in infants undergoing intestinal surgery.

Background: Sodium is a critical growth factor for children. Severe deficits cause growth impairment and cognitive dysfunction. Both the diagnosis and risk of sodium depletion in children undergoing intestinal surgery are poorly understood.

Methods: With IRB approval, children undergoing intestinal surgery (2009-2012) who had a urine sodium measurement were retrospectively reviewed. Sodium deficits were defined: urine sodium <30 mmol/L and <10 mmol/L were deficient and severely deficient, respectively. Demographics, weight changes, and intake (sodium, fluid, and nutritional) were tabulated. Data were analyzed using regression analysis and Mann Whitney U tests.

Results: Thirty-nine patients, 51.3% female, with a gestational age of 32.2 weeks and weight of 1.43 kg were identified. The most common diagnoses were NEC (38.5%), intestinal atresia (20.5%), and isolated perforation (10.3%). Sodium deficiency was documented in 36/39 (92%) and 92.9% for those in continuity. Severe deficiency occurred in 64%. Urine sodium was significantly correlated with weight gain (p=0.002). Weight gain in patients with urine sodium <30 mmol/L was significantly decreased vs. those ≥30 mmol/L (+0.58 g/d vs. +21.6 g/d, p=0.016).

Conclusion: In this population, sodium depletion is common in children undergoing intestinal surgery, even when the colon is in continuity. Correction of the sodium deficit to achieve urine sodium >30 mmol/L is associated with improved weight gain.