Adhesion formation occurs during the natural and normal tissue repair process, when tissue surfaces that usually are separated adhere to each other. The body's cavities and internal organs are covered by membranes. In the abdomen and pelvis, this membrane is known as the peritoneum (The serous sac that lines the abdominal cavity and covers most of the viscera therein). The peritoneum protects and lubricates the external surface of the organs they cover. When the peritoneum is damaged, for example during surgery, a protein called fibrin (a protein derived from fibrinogen) can accumulate on the injured surface, making it sticky. This sticky surface can then adhere to other areas of peritoneum. These sticky bands are called adhesions. Under normal circumstances, fibrin present at the site of mesothelial (An epithelial tissue that lines body cavities and covers visceral organs; also known as the serosa.) damage is broken down by plasmin (An enzyme that converts fibrin to soluble products.). Plasmin is derived from plasminogen, a protein found in the blood. Tissue plasminogen activator (A chemical activator released from mesothelial cells) converts plasminogen into plasmin. Through a process called fibrinolysis, the plasmin then breaks down the fibrin into a substance that is absorbed by the peritoneum.
[ There is an illustration here which displays the EVOLUTION OF A FIBRINOUS ADHESION. This complex illustration is perhaps meant for medical professionals; but some of you will be able to understand the process which is being displayed. ]
Permanent adhesions form when fibrinolysis does not occur following the formation of the fibrin matrix. In the setting of ischemia (reduced blood flow) or inflammation, plasminogen is not activated and plasmin does not form. Consequently, the fibrin cannot be broken down and a permanent adhesion forms.
Adhesions can cause tissues or organs to adhere to each other, often limiting the mobility of organs and inducing pain. Adhesions are associated with chronic abdominal and pelvic pain, intestinal obstruction, female infertility and can make future operations much more difficult.
The incidence of adhesions is overwhelming. ADHESIONS DEVELOP IN UP TO 93 PERCENT OF PATIENTS FOLLOWING ABDOMINAL AND PELVIC SURGERY.
Postsurgical adhesions cause up to 74 percent of bowel obstructions. Over 20 percent of adhesive intestinal obstructions occur within one month of surgery, and up to 40 percent will occur within one year.
The consequences of adhesions are substantial. Postsurgical adhesions are responsible for 20 to 50 percent of chronic pelvic pain cases. Adhesions also are a leading cause of female fertility causing 15 to 20 percent of cases. Quality of life is greatly impaired.
Quite often a patient will undergo surgery to lyse adhesions, only to have them reform. Once a patient has undergone a colorectal procedure, the incidence of reoperation within two years is high--up to 20 percent of those patients will have a subsequent colorectal procedure in that time. Between 2.3 percent and 5 percent of patients will undergo adhesiolysis for bowel obstruction within two years of colorectal surgery.
Reoperations are often complicated by adhesions. Consequently, surgeons must spend a considerable amount of time from ten minutes to hours dividing adhesions before the current procedure can begin. This prolongs the patient's recovery and increases the surgical risk and cost.
The economic impact associated with treating postsurgical adhesions is a tremendous burden on health care. Hospitalizations due to adhesiolysis contributed $1.3 billion to health care expenditures in 1994. During that same year, hospitalizations due to adhesiolysis totaled 846,415 days. When adhesiolysis was the primary procedure, the average length of stay in the hospital was 9.7 days, at an average cost of over $13,000.00.