The Effect of Opioids on the Development of Postoperative Intra-Abdominal Adhesions

Abstract

People addicted to opium rarely develop intra-abdominal adhesions after abdominal surgery. We aimed to evaluate the effect of opium or morphine on preventing postoperative adhesions in rats. Sixty-three rats were randomly divided into a control group, opium-addicted group, and morphine-addicted group in a double-blind study. Drug dependency was checked by using naloxone. Animals were then operated on and the cecum was abraded. At reoperation 3 weeks later the magnitude of adhesions was evaluated by a scoring system. There was a significant difference between the control, opium-addicted, and morphine-addicted groups with regard to the length (P < .001), thickness (P < .05), and severity of adhesions (P < .05). Opium or morphine reduces the severity of postoperative adhesions. Elucidation of the opioid receptor(s) involved in this process would enable the use of selective ligands and offer a pharmacologic strategy in preventing adhesion formation.

Abdominal Adhesions: Current and Novel Therapies

“…Increases cGMP leading to reduced collagen synthesis and increases in fibroblast apoptosis [276,277] Some efficacy in rat models (oral delivery) [278,279] Increased colonic bursting pressure and angiogenesis in rat model in the presence of infection [279] Methylene blue Inhibits NO synthase; reduces free radical oxygen but mechanism in preventing adhesions unknown [280] Some efficacy in rat models [280][281][282] May induce adhesions at high doses [280] Impairs anastomotic healing [282] Catalase Reduces oxidative stress Some efficacy in rat model [283] Vitamin E Antioxidant Efficacy comparable to Seprafilm in rat model [284] Opioids (opium, morphine) Unknown mechanism; postulated that opium receptor decreases inflammation [285] Some efficacy in rat model (reduced length, thickness, and severity) [285] (Continued ) WARD AND PANITCH: ABDOMINAL ADHESIONS: PATHOGENESIS AND SOLUTIONS May reduce oxidative stress [286] Some efficacy in rat bacterial peritonitis model [286] Mixture of lidocaine and prilocaine more effective than lidocaine alone [286] Honey Unknown mechanism; may reduce oxidative stress [287] Some efficacy in rat model (oral delivery [288] and peritoneal delivery [287]) Improved histology and anastomotic busting pressure in rats [288] Sphingosine kinase 1 delivered by adenovirus Enhances mesothelial cell migration accelerating wound healing [289] Some efficacy in rat model [289] neurokinin-1 receptor antagonist (aprepitant, CJ-12-255]…”

Postoperative Adhesions: From Formation to Prevention

“…76 Opioid use has been shown to reduce the severity and extent of postoperative adhesions in animal models. 77 There is no known mechanism how opioids reduce adhesions, but proposed actions include affecting the known steps that promote the adhesion formation such as decreasing inflammation through the inflammatory cells, macrophages, mesothelial cells, platelets, or bioactive substances, and changing the fibrinolysis balance.…”

Endogenous opiates and behavior: 2009

“…(383). Morphine and opium dependence reduced the severity of postoperative adhesions following abdominal gastric surgery (573).…”