Submitted to: Journal of Pediatric Surgery
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/2000
Publication Date: 1/20/2001
Citation: JAKSIC, T., SHEW, S.B., KESHEN, T.H., DZAKOVIC, A., JAHOOR, F. DO CRITICALLY ILL SURGICAL NEONATES HAVE INCREASED ENERGY EXPENDITURE?. JOURNAL OF PEDIATRIC SURGERY. 2001. v. 36(1). p. 63-67. Interpretive Summary: This study sought to determine if severely stressed surgical neonates on a respirator showed increased resting energy expenditures as compared with similarly nourished, clinically stable, postoperative surgical newborns. We hypothesized that neonates obligately redirect energy, normally used for growth, to fuel the stress response, hence, resting energy expenditures would not be elevated in the group on respirators. Such data are useful in evaluating if the routine administration of excess calories is warranted in critically ill surgical neonates.
Technical Abstract: Adult metabolic studies suggest that critically ill patients have increased energy expenditures and thus require higher caloric allotments. To assess whether this is true in surgical neonates the authors utilized a validated, gas leak-independent, nonradioactive, isotopic technique to measure the energy expenditures of a stable postoperative group and a severely stressed cohort. Eight (3.46 ± 1.0 kg), hemodynamically stable, total parenteral nutrition (TPN)-fed, nonventilated, surgical neonates (5 with gastroschisis, 2 with intestinal atresia, and 1 with intestinal volvulus) were studied on postoperative day 15.5 ± 11.9. These were compared with 10 (BW = 3.20 ± 0.2 kg), TPN-fed, extracorporeal life support (ECLS)-dependent neonates, studied on day of life 7.0 ± 2.8. Energy expenditure was obtained using a primed, 3-hour infusion of NaH13CO3, breath 13CO2 enrichment determination by isotope ratio mass spectroscopy, and the application of a standard regression equation. Interleukin (IL)-6 levels and C-reactive protein (CRP) concentrations were measured to assess metabolic stress. Comparisons between groups were made using 2 sample Student's t tests. The result was the mean energy expenditure was 53 ± 5.1 kcal/kg/d (range, 45.6 to 59.8 kcal/kg/d) for the stable cohort and 55 ± 20 kcal/kg/d (range, 32 to 79 kcal/kg/d) for the ECLS group (not significant, P=.83). The IL-6 and CRP levels were significantly higher in the ECLS group (29 ± 11.5 v 0.7 ± 0.6 pg/mL [P<.001], and 31 ± 22 v 0.6 ± 1.3 mg/L [P<.001], respectively). Mortality rate was 0% for the stable postoperative patients and 30% for the ECLS group. Severely stressed surgical neonates, compared with controls, generally do not show increased energy expenditures as assessed by isotopic dilution methods. These data suggest that the routine administration of excess calories may not be warranted in critically ill surgical neonates and support the hypothesis that neonates obligately redirect energy, normally used for growth, to fuel the stress response.