Inflammatory response in patients requiring parenteral nutrition: comparison of a new fish-oil-containing emulsion (SMOF^®) versus an olive/soybean oil-based formula

Introduction

Lipid emulsions are an essential part of parenteral nutrition (PN), such as energy supply and source of essential fatty acids. It has been shown that the composition of cell membranes is influenced by the fatty acid profile of dietary lipids, and may therefore be responsible for modulations in immune response. The aim of this study was to assess the effects of a new lipid emulsion based on soybean oil, medium-chain triglycerides, olive oil and fish oil (SMOF^®) compared with a lipid emulsion based on olive and soybean oil (ClinOleic^®) on the inflammatory response in postoperative ICU patients.

Methods

A prospective randomised study. After approval from the ethical committee, 44 postoperative surgical patients with an indication for PN were included in this study. Nonprotein calories were given as 60% glucose and 40% lipid emulsion. The total energy intake per day was calculated as 25 kcal/kg body weight. The sedation regimen was standardized, excluding propofol administration. Patients were thus allocated to one of two nutrition regimens: group A (n = 22) received SMOFlipid^® 20%, and group B (n = 22) a lipid emulsion based on olive and soybean oil (ClinOleic^® 20%). Lipid emulsions were administered during 5 days postoperatively, corresponding to the observation time. IL-6, TNFα, and soluble E-selectin levels (sE-selectin) were measured before the start of infusion (d0), at day 2 (d2) and at day 5 (d5) after the start of administration. The significance level was defined at P < 0.05.

Results

There were no significant differences between the two groups in the inflammatory response at d0 and d2. But at d5, significantly lower IL-6 (group A: 73 ± 58 vs group B: 123 ± 107 pg/ml), TNFα (group A: 15.2 ± 7.9 vs group B: 22.6 ± 12.9 pg/nl), and soluble E-selectin concentrations (group A: 21.5 ± 13.7 vs group B: 32.6 ± 21.2 ng/ml) were seen in patients receiving SMOF^® compared with patients administered ClinOleic^®.

Conclusion

The administration of SMOFlipid^® within a PN regimen led to a significantly reduced inflammatory response at day 5 of the nutrition regimen compared with a lipid emulsion based on olive and soybean oil, including measurements of IL-6, TNFα, and soluble E-selectin values.