Fish oil improves hemodynamic stabilization and inflammation after resuscitation in a rat model of hemorrhagic shock

Background: Hemorrhagic shock followed by resuscitation stimulates an inflammatory response. This study tests the hypothesis that treatment with fish oil will attenuate inflammatory responses and stabilize hemodynamics. Methods: Male SD rats (n = 48; 250 similar to 300 g) were randomly divided into 4 groups: SHAM, hemorrhagic shock (HS), hemorrhagic shock/resuscitation (HS/R) and fish oil (FO). Shock was induced, and a mean arterial pressure (MAP) was maintained at 35 to 40 mmHg for 60 minutes. Resuscitation was carried out by returning half of the shed blood and Ringer's lactate solution to the animal. In FO group, fish oil (0.2 g/Kg) was infused through caudal vena at 30 minutes after shock. Half of each group was killed at 30 minutes and at 4 hours after resuscitation. Then several kinds of inflammation and oxidative stress indicators such as IL-6, MPO and GSH were tested. Result: FO group required less resuscitative fluid and had higher urinary output at the recovery periods from hemorrhagic shock than HS/R group(p < 0.001). After resuscitation, the MAP of HS/R group markedly declined than FO group (p < 0.001). The inflammatory indexes of FO group were lower than HS group and HS/R group and the same as sham group. But the level of endotoxin in FO group was significantly higher than sham group at 4 hours. Conclusion: Fish oil pretreatment before fluid resuscitation showed a beneficial effect to the hemodynamic stabilization and inflammation reduction in HS/R rat model.