Postoperative intra-abdominal adhesion (PIAA) is a common complication following abdominal surgeries. Up to now, no practical method or device has been proven to be the gold standard in PIAA formation prevention. This study was designed to evaluate the effects of oral and intraperitoneal tamoxifen citrate on PIAA formation prevention.
A total of 48 guinea pigs weighing 300–350 g were included in four groups (12 pigs in each group). Under general anesthesia, laparotomy was performed, and a part of small bowel was abraded using wet gauze so that serosal petechiae developed on the intestinal surface for induction of peritoneal adhesion. In group 1 (control), only this adhesion induction was performed with no treatment. In the second group, 2.5 mg/kg/day tamoxifen citrate was administered by orogastric gavage postoperatively. Group 3 underwent adhesion induction and then intraperitoneal administration of 2.5 mg/kg tamoxifen citrate diluted in 10 ml of aquapura. Group 4, underwent adhesion induction and intraperitoneal administration of 2.5 mg/kg tamoxifen citrate diluted in 10 ml aquapura and then 2.5 mg/kg/day tamoxifen citrate was administered by orogastric gavage postoperatively. Pigs underwent laparotomy on the eighth postoperative day, and grading of adhesions was performed according to the Adhesion Characteristic and Adhesion Tenacity scoring system. Data were analyzed using SPSS for Windows version 16.
The control group was significantly different from other groups (p < 0.008), which means usage of tamoxifen (oral or intraperitoneal or both) significantly reduced adhesion formation after laparotomy. Intraperitoneal tamoxifen (group 3) was more effective in prevention of adhesion formation than oral tamoxifen application (group 2; p = 0.006). Also, administration of both oral and intraperitoneal tamoxifen (group 4) reduced adhesions significantly (p = 0.002) in comparison with just oral one (group 2), but it made no difference (p = 0.625) with only intraperitoneal tamoxifen (group 3).
This study indicated that tamoxifen significantly reduces PIAAs, and intraperitoneal application is more effective than oral administration. This study shows that preventive effects of intraperitoneal application of tamoxifen will not improve when oral tamoxifen is added postoperatively. More studies with focus on evaluation of probable side effects and also performing clinical trials for evaluating tamoxifen for preventing PIAAs are strongly suggested.