The results of a prospective, multi-centre, randomised, double-blind and controlled trial designed to investigate if eicosapentaenoic acid (EPA) and gamma-linolenic acid (GLA) could play a role in patients with early sepsis are published in this month’s Journal of Critical Care.
Sepsis is an illness caused by a bacterial infection that can start anywhere in the body. Severe sepsis accounts for around 20% of all admissions to intensive care units and is the leading cause of death in non-cardiac intensive care units. Several studies using animal models of sepsis have demonstrated that enteral nutrition enriched with eicosapentaenoic acid (EPA) and gamma-linolenic acid (GLA), is beneficial with regard to modulating sepsis; the study by Pontes-Arruda and colleagues support such findings in hospital patients.
Providing good nutritional care in NHS hospitals is key to recovery, and patients with poor or incorrect nutrition are at a higher risk of impaired immunity, poor wound healing and decreased muscle strength and may be at risk of increased infection. In circumstances where a patient is unable to eat normally, enteral nutrition provides a special liquid food mixture containing protein, carbohydrates, fats, vitamins and minerals, directly through a tube into the stomach or small bowel.
Lipid emulsions within enteral feeds are crucial for providing specific fatty acids and energy; until fairly recently, however, essential fatty acids have been entirely omitted from enteral solutions or included only in the form of omega-6 polyunsaturated fatty acids linolenic acid (LA) and arachidonic acid (AA). While these fatty acids are structurally important for cell membranes and play a significant role as precursors (especially AA) of eicosanoids (prostaglandins, thromboxanes, leukotrienes), in the absence of omega–3 polyunsaturated fatty acids, these eicosanoids may produce exaggerated effects in acute stress responses, causing immunosuppression, platelet aggregation and excessive or chronic inflammation. Omega-3 polyunsaturated fatty acids act as precursors of complementary eicosanoids, which counteract the exaggerated responses of AA-derived eicosanoids. The inclusion of omega-6 GLA further contributes to the inhibition of AA-derived eicosanoids by shuttling the omega-6 pathway down an inflammatory route.
In the present study, a total of 106 patients with severe sepsis or septic shock, requiring mechanical ventilation and tolerating enteral nutrition, were allocated to receive for 7 days either an EPA/GLA diet or an isocaloric, isonitrogenous control diet not enhanced with lipids, and all clinical outcomes were recorded during a 28-day follow-up period. In comparison to those patients in the control group, patients fed diets enriched with EPA and GLA were associated with less development of severe sepsis/septic shock, primarily due to a reduced number of cardiovascular and respiratory failures in the study. Patients also spent less time in the intensive care unit, with an overall shorter time in hospital. Such findings, whilst the first of their kind, represent an important reduction in the overall cost of care for the treatment of this population of patient.
The authors highlight the importance of producing further evidence and of reproducing these findings in a more broad population of patients with early stages of sepsis, perhaps using an EPA/GLA oral supplement, thus not having to deliver these pharmaconutrients only when an enteral feeding tube is in place.
Pontes-Arruda A., Martins L., de Lima S, Isola A., Toledo D., Rezende E., Marcelo Maia M., Magnan G. INTERSEPT (Investigating Nutritional Therapy with EPA, GLA and antioxidants Role in Sepsis Treatment) Study GroupEnteral nutrition with eicosapentaenoic acid, gamma-linolenic acid and antioxidants in the early treatment of sepsis: results from a multicenter,prospective, randomized, double blinded and controlled Study – INTERSEPTstudy. Critical Care 2011, 15:R144