[The protective role of hyperoxic Ringer's solution on the hepatic injury in rats with burn shock].

Objective: To explore the dynamic postburn changes in rat hepatic function and the effects of hyperoxic Ringer's solution resuscitation on the function.

Methods: One hundred and ninety Wistar rats of both sexes with body weight of 250 - 300 g were employed as the model and were divided into 6 groups as A, B, C, D, E and F groups as follows: normal control (A, n = 10), early resuscitation with Ringer's solution (B, n = 40), delayed resuscitation with Ringer's solution (C, n = 30), early resuscitation with hyperoxic Ringer's solution (D, n = 40), delayed hyperoxic Ringer's solution resuscitation (E, n = 30) and burn control (F, n = 40). Blood samples were drawn from the injured rats under anesthesia at 6, 12, 24 and 48 postburn hours (PBHs), and the serum contents of ALT, AST and MDA in these blood samples were determined. Hepatic tissue samples were also harvested at the same time and served histologically.

Results: The plasma ALT level at 6 PBH in all groups was higher than that in A group (P < 0.05). There was significant difference of plasma ALT levels between hyperoxic Ringer's solution treatment group an other treatment groups (P < 0.05). And there was evident difference of plasma ALT levels between hyperoxic Ringer's solution treatment groups and other treatment groups (P < 0.05). The dynamic change in plasma AST was almost similar to that of ALT. The plasma MDA level was increased obviously after injury, especially in F group (highest level). Furthermore, the MDA level in C group was higher than that in B group. The plasma MDA levels in D and E groups were evidently lower than that in all other groups (P < 0.05). It was revealed by histological examination that there were different degrees of degeneration an necrosis of hepatocytes during early postburn stage, but less so in D group.

Conclusion: Fluid resuscitation during early postburn stage with hyperoxic Ringer's solution could inhibit the production of oxygen free radicals and blunt lipid peroxidation, and it could also enhance the host tolerance to hypoxia and prevent hepatocytes from injury, thus hepatic function was protected.