Omega 3 Fatty Acids in Parenteral Nutrition Erin Buehler Lauryn Whitfield

Background Most patients, especially critically ill, experience inflammation due to trauma or disease When oral intake or enteral feeding is not tolerated, patients may be placed on parenteral nutrition Currently, the majority or parenteral solutions use safflower/soybean oil as a source of lipids, both containing high amounts of omega-6 polyunsaturated fatty acids

Lipids in Parenteral Nutrition Disadvantages Elevate triglycerides: bypasses the lymphatic system Advantages Provide energy and cellular building blocks Decreases risk of hyperglycemia Provides fat soluble vitamins Precursors to metabolically pertinent prostaglandins and eicosanoids

Omega 6 vs. Omega 3 Fatty Acids Omega- 6 PUFA Pro-inflammatory Precursors of inflammatory mediators: leukotrienes and prostaglandins Omega-3 PUFA Anti-inflammatory Promote hemodynamic stability Quickly incorporated into immune cell membranes Increase stability and fluidity of the cell membrane Less thrombogenic effects Better T-cell immune function

Critically Ill May decrease length of hospital stay Does not decrease mortality rates In a study with an omega-3 to omega-6 ratio of 1:2, no statistically significant differences between length of stay, nosocomial infections, duration of mechanical ventilation, and inflammatory markers

Colorectal Cancer Decreases tumor protein synthesis and inhibits tumor growth In one study, a statistically significant decrease in interleukin-6 and TNF-alpha levels were found Some studies do not show the same effects in all cancers

Parenteral Nutrition Associated Liver Disease Ectopic fat deposits are common with long term use of parenteral nutrition Omega-3 fatty acids can prevent or correct these complications The appropriate ratio is still undetermined Decreases liver availability of fatty acids for VLDL synthesis and secretion

Other Conditions Spinal Cord Injuries Mouse study Less cell death in the spinal cord Improved locomotor performance during recovery time Arachidonic acid is detrimental after injury, but omega-3 fatty acids can inhibit the action of AA General Surgery Inflammation post surgery is partly due to proinflammatory mediators (leukotrienes and prostaglandins) Omega-3 fatty acids counteract these effects Decreases mortality rates

Conclusions General consensus among studies that use of omega-3 FA in PN produces no harmful effects Use has shown to be beneficial in various disease states/conditions Currently, there is no appropriate ratio determined Should FDA approve use of omega-3 FA in PN?

Areas for Future Research More randomized controlled trials with larger samples and longer durations should be conducted to determine the appropriate ratio of omega-3:omega-6 FA More research on the efficacy of omega-3 in PN in the critically ill