Background   Recent studies have shown that pyruvate is effective in treating hypovolemic shock caused by burn. However, the safety of oral administration of sodium pyruvate, which is the most studied at present, is low, which makes it difficult for its oral preparation to be applied in clinical practice. However, the food-grade product of calcium pyruvate has been put on the market with high edible safety, so it has broad prospects in oral liquid resuscitation. At present, there is no relevant research on calcium pyruvate for anti-shock at home and abroad. In this experiment, calcium pyruvate is introduced into the classic WHO oral rehydration salt Ⅲ, and its value in resuscitation in pre-hospital emergency stage is evaluated.

  Objective   To investigate the effects of calcium pyruvate oral rehydration solution on oxygenation, organ function and survival rate of severely burned rats.

  Methods   Before the experiment, 4 packets of oral rehydration salts Ⅲ recommended by WHO and 6.8 g calcium pyruvate were mixed and dissolved in 1 000 mL drinking water. The osmotic pressure of the solution was 290 mmol/L and then preheated it to 37℃. Totally 210 male wistar rats (6-8 weeks old, 210-230 g) were included and they were randomly divided into sham injury group (Sham group, n=30), simple burn group (Burn group, n=60), oral rehydration group (OR group, n=60) and intraperitoneal rehydration group (PR group, n=60). Sham group was soaked in water at 37℃ while the other three groups were soaked in boiling water at 94℃ for 12 seconds on their back and 6 seconds on their abdomen, which were inflicted with 50% total body surface area full-thickness scald on the back and abdomen. The OR group received calcium pyruvate oral solution while the PR group received lactate ringer’s solution. Both groups started rehydration at 2 minutes after injury. The rehydration volume was based on Parkland formula. Total rehydration time was 8 h. The Sham group drank water freely while the Burn group did not receive rehydration. After 8 h, all groups drank water freely. Twenty rats in each group were selected to observe the 24-hour survival rate. At 0.5 h, 4 h, 8 h and 24 h after injury, 10 rats were selected from each group to measure blood gas analysis indexes, organ function indexes, oxidative stress indexes and histopathological changes.

  Results   The 24-hour survival rates of the OR group and PR group were significantly higher than that of the Burn group (70%, 75% vs 30%) (P＜0.05); At 4 h, 8 h and 24 h after injury, the indexes and histopathology of the OR and the PR groups were significantly improved compared with those of the Burn group; and at 8 h and 24 h after injury, Lac, AST and T-AOC in the OR group were significantly improved compared with those of the PR group (P＜0.05).

  Conclusion   Calcium pyruvate oral rehydration solution can improve ischemia, hypoxia, oxygenation and protect organ function, improve antioxidant capacity and 24-hour survival rate of severely burned rats. The resuscitation effect of calcium pyruvate oral rehydration solution is similar to that of intraperitoneal supplementation of Ringer's lactate solution.