Effects of preoperative oral carbohydrate supplementation on postoperative metabolic stress response of patients undergoing elective abdominal surgery.

BACKGROUND: The goal of the present study was to evaluate the effects of preoperative oral carbohydrate supplementation (OCH) on the postoperative metabolic stress response of patients undergoing elective abdominal surgery. METHODS: The study was designed as a controlled, prospective, cohort study including 38 patients treated with OCH (800 mL the day before surgery and 400 mL within 3 h before the induction of anesthesia) and 38 controls matched for surgical procedure. Fasting glucose, insulin, insulin resistance (HOMA-IR index), cortisol, and interleukin 6 (IL-6) were assessed before and after surgery (postoperative day (POD) 1, 2, and 3). RESULTS: The administration of OCH resulted in lower fasting glucose, HOMA-IR index, cortisol, and IL-6 on both POD 1 and POD 2. At multivariable regression analyses, the reduction of these parameters was independent of sex, age, body mass index, and major abdominal surgery. Particularly, models including OCH treatment explained 70, 63, and 66 % of the variance of the increase in IL-6 levels at POD 1, POD 2, and POD 3, respectively. The effect of OCH on changes in glucose, insulin resistance, and cortisol on POD 1 and POD 2 disappeared after the inclusion of IL-6 in the models. CONCLUSIONS: Treatment with OCH was associated with attenuation of the postoperative metabolic stress response. We hypothesize that modulation of the inflammatory response is one of the mechanisms involved.

Age-related changes in intracellular TH1/TH2 cytokine production, immunoproliferative T lymphocyte response and natural killer cell activity in newborns, children and adults.

To evaluate the development of the neonatal immune system, we measured T lymphocyte response to Con A, intracellular IL-2, IL-4, IFN-gamma and IL-10 production, and natural killer cell (NKC) activity in 12 very preterm, 12 preterm and 20 term neonates, 10 children and 10 adults. Immunoproliferation to Con A was significantly lower in cord blood than in children or adults. The percentage of CD4+ lymphocytes was significantly higher in newborns while CD8+ cells were higher at older ages, with a resulting gradual decline of the CD4+/CD8+ ratio. The percentage of IL-2-producing CD4+ and CD8+ cells was higher in all newborn groups than in children and adults, while the percentage of IL-4-producing cells was higher for CD8+ and lower for CD4+ cells in cord blood than in children and adults. Neonates had substantially lower percentages of CD4+ and CD8+ IFN-gamma-producing cells. A significant negative correlation was observed between gestational age and IFN-gamma-CD4+-, IL-2-CD8+-, and IL-10- CD4+-producing cells. In addition, a positive correlation was found between gestational age and IL-10-CD8+-producing cells. Percentages of CD4+/CD45RA+ cells were higher and CD4+/CD45RO+ percentages were lower in newborns than in children and adults. NKC activity in infants was significantly correlated with gestational age and significantly impaired compared to children and adults. On the whole, these results suggest a gradual development of immunity during gestation and show significant immaturity of cellular immune response at birth. The reduction of NKC activity, the lower proliferative response of T cells, the reduced cytotoxic response and a dysregulated cytokine production may contribute to the neonatal increased risk of infection and to the low incidence of graft-versus-host disease after cord blood transplantation.