Comparative effectiveness of several agents for preventing postoperative adhesions

Postoperative adhesions (PAs) are usually clinically asymptomatic. Symptomatic cases, however, may present with chronic abdominal and pelvic pain, infertility, and intestinal obstruction; and they may require intensive, costly therapeutic modalities. Various agents have been used to prevent PAs, but the results indicate general suboptimal effectiveness. Our objective was to evaluate the comparative effectiveness of two pharmacologic agents for preventing PA: nadroparine calcium (low-molecular-weight heparin, or LMWH) and aprotinin, as well as a barrier agent, sodium hyaluronate/carboxymethycellulose (SCMC). Our subjects were 40 male Wistar-Albino rats divided into four groups, each consisting of 10 rats, which underwent standard cecal abrasion preceding midline laparotomy. In the control group (group 1) 1 ml of 0.9% NaCl was administered intraperitoneally before abdominal closure. In the three preventive groups, 100 U AXa (anti factor X activity) LMWH, 1800 IU aprotinin, and SCMC were administered intraperitoneally to groups 2, 3, and 4, respectively. Relaparotomy was performed on the 14th postoperative day. Visceral and abdominal wall adhesions were scored in a blinded fashion. The adhesion scores (mean +/- SD) for groups 1, 2, 3, and 4 were 2.00 +/- 0.67, 0.6.00 +/- 0.84, 1.10 +/- 0.74, and 0.20 +/- 0.42, respectively. The differences in the adhesion scores among all three preventive groups (groups 2, 3, 4) were statistically significant when compared with the control group ( p < 0.001, p = 0.017, p < 0.001, respectively). Intraperitoneal SCMC and administration of LMWH were more effective than giving aprotinin.