The effect of growth hormone on nutritional markers in enterally fed immobilized trauma patients.

BACKGROUND: Earlier clinical studies have demonstrated improved nitrogen balance in nonstressed patients receiving hypocaloric feedings and growth hormone (GH). This study investigates the effect of GH on nitrogen balance, on serum protein concentrations, and on other indices of nutrition when combined with enteral feeding in immobilized patients after closed-head injury or spinal cord injury. METHODS: Sixteen patients who tolerated enteral feedings and remained nonseptic were randomized to receive either placebo or 0.2 mg/kg recombinant human GH for 7 to 13 days. Nitrogen balances were collected daily, and serum proteins were measured at study entrance and exit. RESULTS: GH treatment resulted in higher GH and insulin-like growth factor-1 concentrations but did not improve nitrogen balance. GH treatment also resulted in increased transferrin and serum albumin levels and total lymphocyte count during the study period. CONCLUSIONS: Adjuvant recombinant human GH has no effect on nitrogen balance in highly stressed, totally immobilized patients after head or spinal cord injury, but it significantly enhances constitutive serum protein concentrations and other indices of nutritional repletion.

Visceral protein response to enteral versus parenteral nutrition and sepsis in patients with trauma.

BACKGROUND: Sepsis and the route of nutrient administration are clearly related to visceral protein levels; however, the mechanisms and amount of influence are not completely defined. METHODS: Constitutive and acute-phase protein levels were measured on days 1, 4, 7, and 10 in 68 severely injured patients with abdominal trauma indexes of 15 or more randomized to enteral or parenteral feeding. Groups were matched for age, abdominal trauma index, injury severity score, and length of stay. RESULTS: Significantly higher levels of constitutive proteins and lower levels of acute-phase proteins were found in patients randomized to enteral feeding. Although some "hepatic protein reprioritization" appeared to be caused by nutrient route, this appeared only in the less severely injured patients. A more important factor in visceral protein levels is a reduction in septic morbidity associated with enteral feeding. CONCLUSIONS: Enteral feeding produces greater increase in constitutive proteins and greater decreases in acute-phase proteins after severe trauma primarily caused by reduced septic morbidity with enteral feeding.

Comparison of specialized and standard enteral formulas in trauma patients.

STUDY OBJECTIVE: To compare selected nutrition and immunologic markers and infection in trauma patients receiving a specialized enteral formula with those receiving standard enteral therapy. DESIGN: Prospective, randomized clinical trial. SETTING: Level 1 trauma center at a county government hospital. PATIENTS: Forty-one consecutive patients with major trauma who required enteral nutrition support. Thirty-seven patients completed the study. Four patients (two in each group) were excluded, as additional operative procedures prevented initiation of enteral feedings within 7 days of injury. INTERVENTIONS: Nineteen patients fed the specialized enteral formula received supplemental arginine, linolenic acid, beta-carotene, and hydrolyzed protein for up to 10 days. Eighteen control patients received standard enteral nutrition. MEASUREMENTS AND MAIN RESULTS: After study entry, patients who received the specialized enteral formula had fewer infections than those receiving standard enteral nutrition (3/19 vs 10/18; p < 0.05). The change in nitrogen balance was significantly better (p < 0.05) from day 1 (-11.8 +/- 1.8 g/day) to day 5 (-5.9 +/- 2.0 g/day) for the group who received the specialized formula compared with the group who received standard enteral nutrition (-7.3 +/- 1.7 g/day to -7.4 +/- 2.8 g/day). Similarly, the change in C-reactive protein serum concentration was significantly better (p < 0.05) from day 1 (18.0 +/- 2.1 mg/dl) to day 5 (11.8 +/- 1.5 mg/dl) in the group who received the specialized formula compared with the group who received standard enteral nutrition (17.6 +/- 1.2 mg/dl to 14.4 +/- 1.7 mg/dl). The CD4:CD8 ratio increased more in the group who received the specialized formula, although this difference did not reach statistical significance. CONCLUSION: Trauma patients who received the specialized enteral formula demonstrated a decreased incidence of infection and increased improvements in nitrogen balance and other indexes of stress. Additional clinical trials demonstrating positive patient outcomes are necessary before these specialized enteral formulas are used as the standard of practice in critically ill patients.

Effect of hypoalbuminemia and parenteral nutrition on free water excretion and electrolyte-free water resorption.

OBJECTIVE: To measure the effect of human albumin supplementation during parenteral nutrition on serum albumin concentrations, colloid oncotic pressure, free water clearance, electrolyte-free water resorption, and sodium excretion. DESIGN: Prospective, randomized, controlled trial. SETTING: Tertiary care center. PATIENTS: Thirty adult, hypoalbuminemic patients who required parenteral nutrition. INTERVENTIONS: Parenteral nutrition (control) or parenteral nutrition plus human albumin 25 g/L as a continuous infusion (treatment) for a 5-day study period. MEASUREMENTS: On days 1 and 5, serum albumin concentration, colloid oncotic pressure, free water clearance, electrolyte-free water resorption, and sodium excretion were measured. RESULTS: Serum albumin concentrations increased significantly from day 1 to day 5 in both groups (control: 2.0 +/- 0.1 [mean +/- SEM] vs. 2.3 +/- 0.1 g/dL [20 +/- 1 vs. 23 +/- 1 g/L], p = .02; treatment: 2.2 +/- 0.1 vs. 3.5 +/- 0.2 g/dL [22 +/- 1 vs. 35 +/- 2 g/L], p = .0001). Day 5 serum albumin concentrations were significantly higher in the treatment group compared with control (p = .0001). Colloid oncotic pressure increased significantly from day 1 to day 5 in the treatment group (17.8 +/- 0.8 vs. 25.1 +/- 1.0 mm Hg, p = .0001), and was significantly higher than control at day 5 (p = .0001). No significant differences were found for free water clearance, electrolyte-free water resorption, or sodium excretion within or between groups. CONCLUSIONS: In hypoalbuminemic patients, human albumin supplementation during parenteral nutrition results in significant increases in serum albumin concentrations and colloid oncotic pressure, but has no apparent effect on free water clearance, electrolyte-free water resorption, or sodium excretion.

Comparison of tolerance and nutritional outcome between a peptide and a standard enteral formula in critically ill, hypoalbuminemic patients.

Dipeptides have been reported to be more efficiently absorbed from the gastrointestinal tract than free amino acids. The objective of this study was to compare prospectively a peptide enteral formula (PEF) with a standard enteral formula (SEF) for tolerance and nutritional outcome in acutely injured, hypoalbuminemic (less than 3.0 g/dL) patients who require enteral nutrition support. The prevalence of diarrhea and elevated gastric residuals was assessed daily. Prealbumin, transferrin, colloid oncotic pressure, Prognostic Nutritional Index, and nitrogen balance were measured on days 0, 5, and 10 of enteral nutrition support. Forty-one patients received 345 days of enteral nutrition support. Prevalences of diarrhea and elevated gastric residuals were similar between groups. Prealbumin increased and the Prognostic Nutritional Index decreased significantly from baseline at day 10 in both groups. Transferrin increased in both groups, but not significantly. Colloid oncotic pressure increased significantly from baseline at days 5 and 10 in the SEF group and day 10 in the PEF group. Nitrogen balance increased significantly from baseline at days 5 and 10 in each group. The only significant difference between groups was for nitrogen balance at day 10, which was higher in the SEF group. We conclude based upon our selected measurements of tolerance and nutritional outcome PEF seems to offer no advantage over SEF in acutely injured, hypoalbuminemic patients.