Hyperbaric oxygen therapy effects on tissue lesions in acute pancreatitis. Experimental study in rats.

OBJECTIVE To study the effects of hyperbaric oxygen therapy on tissue lesions in an experimental model of acute pancreatitis induced by pancreatic duct ligation. ANIMALS Forty-eight adult female Wistar rats were randomized into two groups (n=24): control group and hyperbaric oxygen therapy group. INTERVENTION The second group was treated with a two-hour daily session of hyperbaric oxygen therapy at 2.5 ATA started 6 hours after pancreatic duct ligation. SETTING The two groups were divided into 3 subgroups of 8 rats each undergoing euthanasia on days 1, 3, and 7 after the acute pancreatitis induction. MAIN OUTCOME MEASURES The pancreas was evaluated according to the following histopathologic criteria: edema, hemorrhage, acinar necrosis and leukocyte infiltration. RESULTS Hyperbaric oxygen therapy was efficient in significantly reducing acinar necrosis on the first day (P=0.049) and the foci of hemorrhage on the seventh day (P=0.050). The edema and leukocyte infiltration did not show the expected reduction. CONCLUSION The utilization of a daily session of hyperbaric oxygen therapy at 2.5 ATA is efficient in reducing the hemorrhage and acinar necrosis but is not sufficient to reduce edema and leukocyte infiltration.