Techniques for Reducing Postoperative Adhesions
The best "treatment" for pelvic adhesions is to prevent or minimze their formation. Much is known about the cause of adhesions. Various techniques and disease states have been suggested to predispose to adhesion formation. Many studies have been performed to document this. They include incomplete hemostasis, foreign bodies, tissue injury, type of suture utilized, amount of crushing and tissue destruction from instrumentation, tissue desiccation, and underlying infection. Many practical techniques may be utilized to minimize aberration from optimal techniques.

The use of gauze and minimally moistened dry sponges may cause significant peritoneal denudation and surface injury. The use of frequent irrigation has been recommended to limit tissue desiccation and keep tissues moistened. Micro-surgical techniques have been developed in an effort to achieve less tissue destruction during surgery while maintaining precise hemostasis in an effort to decrease subsequent fibrin layering and the potential for adhesions. The use of the most acceptable minimally reactive sutures and an effort to not suture unless necessary helps avoid both tissue reaction and subsequent tissue is chemia from suture placement.

Unfortunately, while the use of such microsurgical techniques are important in and of themselves, they will not completely decrease the risk of adhesions. Indeed, studies have suggested that de novo adhesion rates in patients undergoing laparotomy may be greater than 90% when large numbers of sites are evaluated at the time of second look laparoscopy.

Risk Factors for Adhesion Formation
Multiple risks factors have been identified for the formation of adhesions. In one study performed at the time of autopsy the authors reported a 90% incidence of adhesions in patients with multiple previous surgeries, 70% incidence of adhesions in patients with previous gynecologic surgery, a 50% incidence of adhesions with previous appendectomy, and interestingly, a greater than 20% incidence of adhesions in patients with no surgical history. Of even greater interest, a recent publication suggested that myomectomy with a posterior uterine incision may have an incidence of greater than 90% of adhesions from the incision line to bowel, omentum. or the adnexa. Additionally, there has been great interest in the amount of adhesion reformation following lysis of adhesions for laparotomy vs. laparoscopy, as well as the incidence of de novo adhesion formation in laparotomy and laparoscopy.

Compilation studies have suggested that there is a 70% incidence of adhesion reformation with laparotomy and greater than 50% de novo adhesion formation. While adhesions occur following laparoscopic surgery, the amount of de novo adhesions (adhesions at sites in the pelvis where no surgery was done) has been reported in various studies to be only 10% (a reduction of 40% compared to laparotomy).

Pharmacologic Agents in Adhesion Reduction
In an effort to decrease the adhesions in patients, multiple different methodologies have been utilized. Installation of crystalloid, such a lactated ringers, has been performed. While several animal studies demonstrated a significant reduction in adhesions, multiple studies which utilize crystalloid in control patients, demonstrated no significant effect.

Thirty-two percent Dextran-70 (Hyskon) has been evaluated in multiple studies. The ability of Hyskon to draw fluid into the peritoneal cavity produces a "hydro-floatation" of pelvic structures. It was thought that the physical separation of various pelvic structures would prevent the formation of fibrin bands, thus reducing the risk of adhesion formation. Multiple studies have presented conflicting results from ineffective to marginally effective. In general, it is presently felt that this therapy is ineffective and its use has been largely abandoned.

Corticosteroids, antihistamines, and non steroidal anti-inflammatories have all been used by various routes in an effort to decrease adhesion formation. The classic regimen of a steroid with antihistamine has been shown to be ineffective in a well designed study.

Barriers for Adhesion Reduction
Most recently, barriers have been suggested as a means to decrease adherence of one peritoneal structure to another. Presently, two such surgical membranes are marketed in the United States a Gore-tex surgical membrane composed of expanded polytetrafluoroethylene and Interceed (Johnson and Johnson Medical, Inc. Arlington, TX). The Gore-tex surgical membrane has been used for a number of years and was initially approved for cardiovascular work. This membrane is non-absorbable, non-inflammatory, and because of the small pore size of less than one micron, does not allow infiltration into this sheath. Placement of a surgical membrane requires immobilization by either suture or staple. Several studies have recently demonstrated the efficacy of this membrane. Unfortunately, it is currently recommended that the membrane be removed in patients desiring subsequent fertility.

Interceed barrier is an oxidized regenerated cellulose compound. The exposure of interceed to peritoneal fluid causes subsequent breakdown and formation of a gelatinous coating over the applied tissue. It is felt that this coating decreases the formation of fibrin bridges which may lead to adhesion formation. Multiple studies have evaluated interceed as a barrier and results have been inconclusive. It does not have FDA approval for use in adhesion prevention during laparoscopic surgery.

Most recently, efforts have been directed to evaluate a solution, film, and gel composed of hyaluronic acid. While initial studies were discouraging, reformulation of the compound have demonstrated excellent results in animal trials. This product (in addition to others) is presently being evaluated in a multicenter randomized double blind study to determine its safety and effectiveness. It is hoped that in the future liquid or gelatenous applications will prove to be effective in the prevention of postoperative adhesions.

The most effective product for adhesion prevention is yet to be discovered. It is known, however, that a strict adherence to the principles of microsurgery, including minimization of trauma to issue, tissue hydration, use of the least reactive sutures, meticulous control of bleeding, etc. is critical in minimizing postoperative adhesion formation. No liquid or barrier will overcome the devistating effects of poor surgical technique.