Immunonutrition with diets enriched in polyunsaturated fatty acids (PUFAs) are becoming mandatory for multiple trauma patients. Solutions containing single n-6 PUFAs were administered intravenously in an experimental model of trauma. Thirty-five rabbits were studied; 13 controls; 10 administered gamma-linolenic acid (GLA) 30 min after fracture of the right femor; and 12 arachidonic acid (AA). Systolic, diastolic and mean arterial pressures and heart rate were recorded; serum levels of tumor necrosis factor-alpha (TNFalpha), malondialdehyde (MDA) and nitrate were estimated before and after therapy. Mean survival of controls, of animals treated with GLA and of animals treated with AA was 0.80, 1.41 and 3.60 days, respectively. Administration of PUFAs induced higher levels of blood pressure; that of AA decreased serum TNFalpha and tissue bacterial load compared to controls. Intravenous administration of n-6 PUFAs conferred hemodynamic stability and increased survival in a model of trauma rendering further research mandatory.