Effects of intraperitoneal bevacizumab administration on colonic anastomosis and early postoperative adhesion...

The purpose of this study is to investigate the effect of intraperitoneal (IP) bevacizumab on colonic anastomosis and evaluate the effects on early postoperative adhesion formation.

A total of 24 mature female Sprague-Dawley rats were used for this study. Rats were randomly assigned to a control group that received saline (n = 8) or to experimental groups (n = 8 each) that received bevacizumab at a dose of 2.5 mg/kg (group 1) or 5 mg/kg (group 2). Animals were killed humanely on the seventh day after operation, and measurements of anastomotic strength and biochemical variables were performed.

The mean adhesion grade was 2.63 ± 0.92, and 1 ± 0.93 and 0.75 ± 0.71 for the control and test groups, respectively. Bevacizumab significantly reduced adhesion formation in both low-dose and high-dose IP applications (P < .05). When all groups were compared, it was found that VEGF levels decreased significantly only in the tissue (P = .001), whereas there was no significant difference in the blood and the IP fluid (P = .73 and .08, respectively). We evaluated hydroxyproline levels, anastomosis bursting pressure, and histopathological healing scores. When each of these parameters were examined, there was statistical difference between groups (P = .01, .004, and .01, respectively). It was found that these parameters significantly decreased depending on increasing drug dose.

IP administration of bevacizumab effectively reduced the formation of adhesions and caused significant impairment of anastomotic wound healing when standard doses were administered (5 mg/kg), but the 2.5-mg/kg dosage did not affect the anastomotic wound healing and also effectively reduced the formation of adhesions.