Omega-3 Fatty Acids and Postoperative Complications After Colorectal Surgery (omega3)

• In previous studies a complication frequency (infectious complications) of at least 30% was found for this type of operation (14; 17) This figure has to be reduced to 10% (MIREDIF = 20%). [ Time Frame: 1 year ]

  Primary outcome measures are infectious complications after surgery for colorectal cancer defined as: pneumonia, cystitis, wound infection, intraabdominal abscess, peritonitis, septicemia, other infections.

  30 day mortality and other complications such as bleeding, wound dehiscence, anastomotic leakage will also be registered

  
  

• The secondary outcome variable is hospitalisation time and mortality. Given the material's size, it is not expected to be possible to demonstrate a significant reduction in mortality [ Time Frame: 1 year ]
  
• incorporation of fatty acids in cell membranes [ Time Frame: after 7 days of intervention ]
  laboratory test on blood sample (leucocytes
  
  
• development in interleukins after surgery [ Time Frame: day 1-4 after surgery ]
  analysis of blood sample
  
  
• lenght of stay in hospital
  

Several earlier studies indicate that perioperative supplements of Omega-3 fatty acids can reduce the risk of postoperative complications after major surgery through an immune modulating effect in the form of a downward adjustment of the inflammatory response. (1-7) The interpretation of these studies is made more difficult by differences in their method of administration (parentally/enterally), differences in the time of the intervention (preoperative/postoperative) and differences in the selection of patients (malnourished cancer patients / upper GI cancer patients/mixed surgical patients) and finally because many of the studies deal with a so-called immune modulating preparation containing a mixture of arginine, Omega-3 fatty acids and ribonucleic acid.

The biological effects of fish oils are related to their content of such things as Omega-3 fatty acids that can be incorporated in cell membranes where they influence receptor function, enzyme activity and the production of lipid mediators. The cells from the immune system perform their functions through membrane-associated activities like secretion of cytokines, antibodies, lymphocyte transformation and contact lysine. These functions can be affected by changes in the membrane structure. (7;8) Besides the effect parameter of postoperative septic complications, many of these studies use pseudoparameters such as length of stay, need for respirator treatment, time in intensive care as well as a wide range of biochemical changes whose relevance to the clinic process can be difficult to assess. (1-7;9-13;). It is well-known that early enteral nutrition reduces the risk of postoperative complications (14; 15). Many of the aforementioned studies similarly point to a benefit from using Omega-3 fatty acid enriched nutritional preparations preoperatively. There is now a commercially manufactured nutritional preparation for peroral consumption containing Omega-3 fatty acids - Supportan (Fresenius-Kabi). The preparation is more energy intensive than similar drink preparations, but does not otherwise differ in composition from standard preparations. It is approved by the Danish Veterinary and Food Administration for this study.

In 2 x 200ml of Supportan 3 g EPA and DHA are given daily. In other studies up to 10 g have been given daily without side effects. (6; 16)