284 - Association of Serum Electrolytes and Weight Loss in the First 96 Hours and In-Hospital Outcomes of Newborns Born ≤ 30 weeks or ≤1,250 grams

Poster Number: 284
Publication Number: 284.120

Olivia C. Brandon, University of Washington School of Medicine, Roy, WA, United States; Krystle M. Perez, University of Washington School of Medicine, Snohomish, WA, United States; Sarah E. Kolnik, University of Washington School of Medicine, Seattle, WA, United States; Sandra E. Juul, University of Washington, Seattle, WA, United States; Tommy Wood, University of Washington School of Medicine, Seattle, WA, United States; Gregory C. Valentine, University of Washington, Tacoma, WA, United States

Background: Lower gestational age and birthweight are risk factors for developing intraventricular hemorrhage (IVH). IVH prevention bundles limit handling such as daily weighing, relying on serum sodium or osmolality to determine fluid management over the first 72-96h after birth. However, it is uncertain whether serum electrolytes are appropriate proxies to approximate weight loss.

Objective: We sought to determine correlation between weight loss and serum sodium and osmolality. We also evaluated association between serum sodium and osmolality variability in the first 96 hours and in-hospital neonatal outcomes.

Design/Methods: We performed a retrospective cross-sectional study evaluating newborns admitted to a single-center level IV neonatal intensive care unit who were born at ≤30 gestational weeks or ≤1,250g, excluding congenital anomalies. Serum sodium and osmolality variability were measured as coefficients of variation (CoV - standard deviation/mean*100) 0-96h after birth. We evaluated sodium CoV, osmolality CoV, total fluid administration (mL/kg birthweight/day), weight loss (% from birthweight), and urine output (mL/kg birthweight/hr) with respect to in-hospital outcomes including severe IVH (grade III or IV), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), patent ductus arteriosus (PDA), in-hospital mortality, and length of hospital stay.

Results: Among n=202, daily change in serum sodium and osmolality were significantly associated with percent weight change after adjusting for potential confounders; % weight change per mEq/L change was -0.18, 95% CI -0.31, -0.04 and -0.09, 95% CI -0.16, -0.03, respectively; Table 1. Sodium CoV was associated with increased odds of surgical NEC (OR 1.77, 95% CI 1.02, 3.25; Table 2). Osmolality CoV was associated with increased odds of PDA requiring surgical treatment (OR 1.53, 95% CI 1.03, 2.37; Table 2). Percent weight change was significantly associated with severe IVH (OR 1.11, 95% CI 1.01, 1.22).Conclusion(s): Serum sodium and osmolality are correlated with percent weight change in a given 24h period, and increasing variability of serum sodium or osmolality are associated with adverse outcomes including surgically treated NEC or PDA. While increasing percent weight change over the first 96h is associated with severe IVH, it remains uncertain whether reliance on serum biomarkers versus daily weights equally prevent adverse neonatal health outcomes.
CV for Olivia BrandonOlivia Brandon_CV.pdf
Table 2: Sodium and osmolality model summaries of predictors for in-hospital neonatal outcomes