The Role of Hyperbaric Oxygen as a Prophylaxis for Radiation Enteritis

C3H mice were used to study the effects of post radiation treatments of hyperbaric oxygen HBO on preventing onset of radiation enteritis. Fifty mice were irradiated in the abdominal pelvic regions with identical radiation doses of 3000 CGY in 10 fractions over two weeks. The mice were randomly divided into a control and a study group of 25 each. The control group received no other treatment while being maintained with standard nutritional support. The study group preceived 30 HBO treatments 90 min of 100 oxygen at 2.4 ATA for 5 days week for 6 weeks starting 7 weeks after radiation therapy. All mice were sacrificed at 7 months and examined for signs of radiation damage. A numerical scoring system was used to quantitatively evaluate radiation damage to tissue. A score of 30 was determined for the radiation control group consisting of 21 surviving animals while a score of only 3 was noted for the HBO treated study group consisting of 25 surviving animals. Stretch meter examination showed that 7 of 21 control animals possessed stenotic lesions while only 4 of 25 HBO- treated animals were affected. Histological examination for submucosal fibrosis is presently in progress with no apparent differences noted thus far. This study indicates that post-radiation HBO treatments can significantly reduce small bowel radiation damage in mice.