The aim of the present study was to investigate the effect of hyperbaric oxygen therapy (HBOT) on colon anastomosis after chemoradiotherapy (CRT). Sixty female WistarAlbino rats were divided into 5 groups and underwent left colon resection and end-toend anastomosis. CRT simulation was performed on 2 sham groups before the anastomosis, and 1 of these groups was administered additional postoperative HBOT. Two groups were administered CRT before the anastomosis, and 1 of them received additional postoperative HBOT. On postoperative day 5, all groups underwent relaparotomy; burst pressure was measured and samples were obtained for histopathologic and biochemical analysis. There was a significant weight loss in the CRT groups and postoperative HBOT had an improving effect. Significantly decreased burst pressure values increased up to the levels of the controls after HBOT. Hydroxyproline levels were elevated in all groups compared to the control group. Hydroxyproline levels decreased with HBOT after CRT. No significant difference was observed between the groups regarding fibrosis formation at the anastomosis site. However, regression was observed in fibrosis in the group receiving HBOT after CRT. Preoperative CRT affected anastomosis and wound healing unfavorably. These unfavorable effects were alleviated by postoperative HBOT. HBOT improved the mechanical and biochemical parameters of colon anastomosis in rats.Key words: Anastomosis -Chemoradiotherapy -Hyperbaric oxygen -Rat -Burst pressure 2 Although adjuvant therapy has been a well-accepted procedure to prevent metastasis and local recurrence after surgical resection, more recently neoadjuvant therapy has gained popularity to enable secondary curative resection with clear surgical margin and to prolong overall and recurrence-free survival.2 It has been reported that local recurrence rate is lower, toxicity is rare, and the anal sphincter is more likely to be preserved in those undergoing preoperative radiation.
1,2Despite the current advances in surgical techniques, anastomotic leakage is a severe complication leading to morbidity and mortality after intestinal surgery.3-6 Chemoradiotherapy (CRT) has the potential to lead to inadequate vascularization in tissues, a well-known risk factor for intestinal anastomosis leak. Impaired oxygenation as a result of hampered vascularization may lead to delay in wound healing, which ultimately impairs anastomotic durability. Studies on factors that enhance wound healing to prevent anastomotic leakage in colon anastomosis have been accelerated in the past decade. In a limited number of studies performed for this purpose, hyperbaric oxygen therapy (HBOT), which is applied by means of intermittent inhalation of 100% oxygen under 1 atmosphere pressure, has been reported to have favorable effects on intestinal anastomotic healing.7-9 However, whether HBOT can reverse potential side effects of CRT on would healing and anastomotic durability is unclear. The aim of the present study was to investigate the effects of HBOT on the bioche...