Internal scar tissue, known as adhesions, can form within the body following surgical procedures or injuries. These fibrous bands can connect tissues and organs that are normally separate, potentially causing various health complications. Adhesion barriers are medical solutions designed to minimize the formation of internal scar tissue, thereby improving patient outcomes after surgery.
What Are Adhesions?
Adhesions are bands of scar tissue that cause internal tissues and organs to stick together. Normally, internal organs move and slide past each other due to their smooth surfaces. However, inflammation, injury, or surgery can disrupt this natural movement, leading to adhesion formation.
These fibrous connections can appear as thin, transparent sheets or as thick, dense bands. Adhesions commonly form within the abdominal and pelvic cavities, but they can occur almost anywhere in the body, including joints or around the heart. They begin to form within hours or days following tissue disturbance as the body’s repair mechanisms respond to trauma or infection.
While many adhesions are painless, they can lead to complications depending on their location and extent. For instance, abdominal adhesions are a frequent cause of small bowel obstruction, accounting for approximately 60% of cases in adults. Pelvic adhesions can cause chronic pain or infertility by involving organs like the fallopian tubes.
The Role of Adhesion Barriers
An adhesion barrier is a medical material placed inside the body during surgery. Its function is to physically separate healing tissues and organs, preventing them from fusing abnormally. This separation aims to reduce the formation of adhesions.
Surgeons commonly use these barriers as a preventive measure in various procedures, particularly in abdominal and pelvic surgeries. They are applied at the end of a surgery, before the incision is closed. While meticulous surgical techniques can help minimize tissue injury, they may not fully prevent adhesion formation, making adhesion barriers a valuable adjunct.
Adhesion barriers act as a temporary spacer, maintaining physical distance between traumatized tissue surfaces during the initial healing phase. This allows tissues to heal individually without forming problematic connections. Their use can reduce complications such as bowel obstruction, chronic pain, and infertility that arise from postsurgical adhesions.
How Adhesion Barriers Prevent Scar Tissue
Adhesion barriers create a temporary physical separation between adjacent healing tissues after surgery. This “fence” or “spacer” prevents fibroblasts, cells involved in scar tissue formation, from bridging the gap between injured surfaces. The barrier stops these cells from forming abnormal fibrous connections.
The critical period for adhesion development is typically within the first 3 to 7 days after surgery, during which peritoneal healing occurs. During this time, the barrier acts as a physical shield, preventing direct contact and adherence between traumatized tissues. Some barriers are designed to stick to the tissues where applied, ensuring they remain in place.
Depending on the material, the barrier is either absorbed by the body or remains as a permanent implant. For instance, some bioresorbable barriers turn into a gel within one to two days after application and are absorbed from the body within about a week, with complete clearance typically occurring within four weeks. This temporary presence allows sufficient time for initial healing without adhesion formation.
Common Adhesion Barrier Materials
Adhesion barriers come in various forms, including films, fabrics, gels, and solutions, each with distinct compositions. These materials are broadly categorized as natural or synthetic. The choice often depends on the specific surgical site and the surgeon’s preference.
One common type is oxidized regenerated cellulose, supplied as a knitted fabric that swells and gels upon contact with the injured site. Another widely used material is a clear, sticky film composed of chemically modified sugars like sodium hyaluronate and carboxymethylcellulose. This barrier adheres to tissues and is slowly absorbed by the body over approximately seven days.
Liquid or gel-based barriers, such as those derived from hyaluronic acid or icodextrin solutions, are also used. Icodextrin solutions, for example, can be instilled in larger volumes to cause organs to float apart, reducing the likelihood of attachment. Some materials, like expanded polytetrafluoroethylene (ePTFE) membranes, are non-absorbable and may require a second procedure for removal.