Background: The clinical safety and the uptake of n-3 polyunsaturated fatty acids (PUFA) into the serum phospholipids and erythrocyte membranes after administration of fish-oil-supplemented parenteral nutrition (PN) was investigated in colorectal surgical patients.

Methods: Forty patients undergoing colorectal surgery (n = 40) and with an indication for PN were enrolled in a prospective, double-blind, randomized study to receive an n-3 PUFA-supplemented 20% lipid emulsion (Lipoplus; B. Braun Melsungen, Melsungen, Germany; test group, n = 19) for 5 days postoperatively. The control group received a standard 20% fat emulsion (Lipofundin MCT/LCT, B. Braun Melsungen, Melsungen, Germany, control group, n = 21). Clinical outcome parameters and safety were assessed by means of adverse events recording clinical parameters and hematologic analyses. The contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as arachidonic acid (AA), in phospholipid fractions in plasma and in erythrocytes were analyzed preoperatively, on postoperative days 1, 6, and 10 using liquid gas chromatography.

Results: Both fat emulsions were well tolerated, and none of the adverse events was considered to be related to treatment. Postoperative infectious complications occurred in 4 patients of the n-3 PUFA group vs 7 patients in the control group. As compared with the control group, the n-3 PUFA group had significantly increased levels of EPA in the membranes of the erythrocytes in postoperative day 6 (2.0% ± 0.9% vs 0.8% ± 0.5% fatty acid methyl esters, [FAME]) and postoperative day 10 (2.1% ± 0.8% vs 0.9% ± 0.7% FAME, p < .05). Also, the EPA levels in the serum phospholipids were significantly higher than in the control group on the same postoperative days (7.0% ± 2.6% vs 1.3% ± 0.8% and 3.6% ± 1.0% vs 1.0% ± 0.4% FAME, p < .05). The DHA levels in the serum phospholipids were significantly higher in the n-3 PUFA group compared with the control on postoperative days 6 and 10 (11.8% ± 1.9% vs 8.4% ± 1.5% and 11.2% ± 1.6% vs 8.5% ± 1.4% FAME, p < .05). AA levels were not significantly different in the both groups.

Conclusions: n-3-fatty-acids-supplemented fat emulsions for parenteral administration are safe and very well tolerated. This study demonstrates that parenteral administration of n-3-PUFA-enriched fat emulsions leads to increased incorporation of EPA and DHA into phospholipids in serum and erythrocytes, whereas AA levels remain unchanged. Thus, postoperative parenteral administration of n-3-PUFA-enriched lipid emulsions could have an impact on the postoperative inflammatory response after abdominal surgery and could be used in standard postoperative care when PN is indicated.