[Effects of methylene blue on refractory hemorrhagic shock].

OBJECTIVE: To evaluate the effects of methylene blue (MB) on refractory hemorrhagic shock. METHODS: Totally 24 rabbits subjected to prolonged hemorrhagic shock and resuscitation were randomly divided into hemorrhagic shock group (12 rabbits) and MB group (12 rabbits; MB was administered immediately after resuscitation was performed). The plasma levels of tumor necrosis factor alpha (TNFalpha) , interleukin (IL)-6, IL-8, nitric oxide (NO), lactic acid (LA) , and mean arterial pressure (MAP) were detected before shock, immediately after resuscitation, and 0.5, 2, and 4 hours after resuscitation. The 12-hour survival rates were observed. RESULTS: The plasma levels of TNFalpha, IL-6, IL-8, NO and LA after shock were significantly higher than before shock (P <0.01), and maintained at high levels. Compared with the shock group, higher MAP and lower plasma levels of TNFalpha, IL-6, IL-8, NO, and LA were observed in the MB group after resuscitation (P<0.01). The 12-hour survival rates were not significantly different between shock group and MB group. CONCLUSION: Although MB can not improve the prognosis of refractory hemorrhagic shock, it can increase and maintain the MAP and thus play a beneficial role in the treatment of hemorrhagic shock.