Overfeeding-associated hyperglycemia and injury-response homeostasis in critically ill neonates.

BACKGROUND

Injury severity induces a proportionate acute metabolic stress response, associated with increased risk of hyperglycemia. We hypothesized that excess caloric delivery (overfeeding) during high stress states would increase hyperglycemia and disrupt response homeostasis.

METHODS

Gestational age, daily weight, total daily caloric intake, serum C-reactive protein (CRP), prealbumin, and blood glucose concentrations in all acutely-injured premature NICU infants requiring TPN over the past 3years were reviewed. Injury severity was based on CRP and patients were divided into high (CRP ≥50mg/L) versus low (CRP <50mg/L) stress groups. Glycemic variability was used to measure disruption of homeostasis.

RESULTS

Overall sample included N=563 patient days (37 patients; 42 episodes). High stress group pre-albumin levels negatively correlated with CRP levels (R=-0.62, p<0.005). A test of equal variance demonstrated significantly increased high stress glycemic variability (Ha:ratio>1, Pr(F>f)=0.0353). When high stress patients were separated into high caloric intake (≥70kg/kcal/day) versus low caloric intake (<70kg/kcal/day), maximum serum glucose levels were significantly higher with overfeeding (230.33±55.81 vs. 135.71±37.97mg/dL, p<0.004).

CONCLUSION

Higher injury severity induces increased disruption of response homeostasis in critically ill neonates. TPN-associated overfeeding worsens injury-related hyperglycemia in more severely injured infants.

TYPE OF STUDY: Retrospective study.

LEVEL OF EVIDENCE: Level II.