The prevention of adhesion (scar) formation should be a primary goal of all fertility surgery. Efforts can (and should) be undertaken to reduce postoperative adhesion formation by using principles collectively referred to as “microsurgical techniques.” When the infertility surgeon recreates a pelvic organ, opens a previously blocked fallopian tube, removes abnormal structures from within the uterine cavity, ablates endometriosis, or lyses existing pelvic adhesions the restoration of normal anatomy and function often depends on minimizing scar tissue secondary to surgery.
The microsurgical techniques that should be employed include
(1) Very gentle tissue handling (pulling, rubbing and poking the delicate reproductive tissues can result in trauma and adhesion formation),
(2) Meticulous control of bleeding = hemostasis (whole blood within the pelvis is highly irritating to the peritoneal lining and the inflammation that results can lead to adhesion formation),
(3) Use of magnification if necessary (for establishing proper tissue planes during dissection and for determining the degree of reapproximation accomplished when tissues are placed together),
(4) Careful avoidance of infection (administration of antibiotics to prevent reactivation of a dormant infection within say the fallopian tubes, sterile technique in handling the operating instruments),
(5) Maintaining tissue moisture (irrigation is generally better than sponging, preventing desiccation or drying is important since either leads to adhesion formation),
(6) Minimal effective coagulation of bleeding sites (over cauterizing results in ischemia and this may enhance adhesion formation),
(7) Reducing foreign material that is placed intraoperatively (use of small caliber suture material reduces overall bulk, rinsing sterile gloves or similar objects placed intraabdominally removes talc), and
(8) Reducing lateral thermal damage of tissue (lasers, especially ultrapulse [or XJ pulse] and superpulse CO2 lasers, allow application of very high power densities to tissues to accomplish ablation by vaporization with little lateral thermal damage. This is theoretically of great significance)
In theory (although not proven in the existing literature) laparoscopy has an advantage over laparotomy in terms of adhesion formation. With laparoscopy, small abdominal incisions are made and ports maintain access while occluding the holes when no instruments are actively being used. When compared to laparotomy, this should result in less infection (since the sites are not open for the duration of the case), less tissue drying (especially for longer duration cases since tissue drying can be tremendous during open cases), and less tissue trauma secondary to rubbing or moving intraabdominal structures with surgical gloves. Additionally, the laparoscope is able to be placed immediately adjacent to the operative site to enhance visualization of structures that are buried in the pelvis and the laparoscope can magnify tissues slightly. The magnification achieved with the laparoscope is proportional to the distance of the lens from the tissue viewed, such that at a distance of 1 cm from tissue the laparoscope typically magnifies the tissue about 6 fold, at 2 cm about 4 fold, at 3 cm about 2 fold, at 4 cm there is no magnification and at distances greater than 4 cm there is a reduction in size of the viewed tissue.
Adjuvants are materials that can be used to help prevent adhesion formation. The two primary classes of adjuvants include mechanical barriers and surgical adjuvants.
Mechanical barriers include Gore-Tex surgical membranes (that must be sewn into position), Interceed TC-7 (a material placed over raw surfaces), and 32% Dextran 70 (a highly concentrated sugar like solution made up of high molecular weight glucose polymers that draws in water to act as a mechanical barrier between structures).
Of these barriers, Interceed seems to be the most commonly used. Literature from several clinical reports support a role for Interceed in adhesion prevention.
32% Dextran 70 (Hyskon) has been popular in the past and is still in use in some centers. Mechanical separation of raw surfaces is associated with the water drawn into the concentrated solution (hydroflotation) and a siliconizing effect (the solution is slick). When 200 cc of 32% Dextran is placed intraperitioneally there is usually some ascites for up to a week, and patients occasionally complain of fluid leaking from the incision sites, labial swelling, bloating and weight gain.
Surgical adjuvants include antiinflammatory drugs, anticoagulants, prophylactic antibiotics, calcium channel blockers and plasminogen activators.
The antiinflammatory drugs include corticosteroids (intended to decrease vascular permeability and enhance lysosomal stabilization, each of which should limit adhesion formation), antihistamines (intended to decrease vascular permeability and decrease fibroblast proliferation, each of which should limit adhesion formation), and nonsteroidal antiinflammatory agents like motrin (reduces prostaglandin formation to limit adhesion formation). None of these agents has been shown to be beneficial in terms of adhesion formation in large clinical trials but they are often used by physicians whose personal experience with the medications has been favorable. I do not (currently) use these agents.
Anticoagulants include low dose heparin (about 1-5 units/mL) within irrigation solutions. High doses of heparin should not be used because there is an increased chance of hemorrhagic surgical complications. Low dose heparin has not been shown to be of benefit in terms of adhesion formation in clinical trials.
Antibiotics may reduce the incidence of infection when given prophylactically. The goal is to achieve adequate doses at the tissue sites during the surgery. Vibramycin is often used for tubal surgery since it effectively treats Chlamydia. Many of the higher generation cephalosporins also work well for gynecological pelvic surgery. I typically use cefotetan or mefoxin (depending on availability).
Calcium channel blockers have been used in hamsters with good results, but human studies are lacking. In theory, these agents decrease tissue ischemia, limit prostaglandins, reduce platelet aggregation, and limit vasoconstriction. The use of these agents is awaiting appropriate human trials.
Plasminogen activators accelerate fibrinolysis to reduce the bulk of fibrin clots. Use of these agents is also awaiting appropriate human clinical trials.
Available Case Reports: