Poster Topical Area: Nutritional Immunology
Location: Hall D
Poster Board Number: 849
Objective: Optimal feeding in patients with sepsis is critical to preserve muscle mass. However, it remains unclear whether nutrition is able to induce the required anabolic response during the early treatment phase of sepsis. Therefore, we assessed the anabolic response to a balanced free total amino acid (TAA) or essential amino acid (EAA) mixture by measuring whole body protein synthesis (WbPS), protein breakdown (WbPB), net protein synthesis (netPS), splanchnic extraction (SPE) and protein conversion (ProtConv) in the early recovery phase of acute severe septic pig.
Methods: In catheterized pigs (±25kg), acute severe sepsis was induced in 6 hours (Pseudomonas aeruginosa 3e8 CFU/ml/h IV). Recovery was started by a single dose of gentamycin (5 mg/kg bw). Subsequently, each pig received intra-gastric continuous feeding of a TAA or EAA mixture (pig muscle amino acid profile, 31 mg N/kg bw/h, 30% daily intake, dextrose 781 mg/kg bw/h) for 6 hours. In 3 groups (Healthy: H-TAA n=12; Sepsis: S-TAA n=13, S-EAA n=12) we measured WbPB, WbPS, netPS, SPE and ProtConv (netPS/EAA intake) using primed-continuous intravenous infusion of phenylalanine-[ring-2H5] and tyrosine-[13C9, 15N] and continuous enteral phenylalanine-[1-13C] stable tracers, and collected arterial blood between 3-6h after start of feeding. We analyzed plasma amino acid enrichments by LC-MS/MS and statistics by two-way ANOVA (Graphpad Prism6), significance: p<0.05.
Results: Compared to H-TAA, S-TAA showed a higher WbPB and SPE (p<0.0001), a lower netPS rate and ProtConv fraction (p<0.0001), but unchanged WbPS (p=0.989). Compared to S-TAA, S-EAA showed a higher netPS, WbPS, ProtConv (p<0.0001) and lower SPE (p=0.0006), but unchanged WbPB (p=0.7811). NetPS in S-EAA group was higher comparing to H-TAA (p<0.0001).
Conclusions: In the early treatment phase after acute severe sepsis, the whole body anabolic response to TAA nutrition is severely compromised. However, EAA was able to restore the anabolic response substantially, mainly through an enhanced whole body protein synthesis. We hypothesize that this was accommodated by a lower SPE
Gabriella Ten Have
Texas A&M university