What is the pathogenesis and clinical significance of intra-abdominal adhesions, including their formation and potential complications?

From the Guidelines

Intra-abdominal adhesions are abnormal bands of fibrous tissue that form between abdominal organs and tissues that are normally separate, primarily developing as a consequence of the body's healing response following abdominal surgery, inflammation, infection, or trauma, with approximately 90% of patients developing adhesions after open abdominal procedures 1.

Formation of Intra-Abdominal Adhesions

The formation of intra-abdominal adhesions is a complex process that involves the body's healing response to injury. When the peritoneum, the membrane lining the abdominal cavity, is injured, the body initiates an inflammatory response that deposits fibrin at the injury site. Normally, this fibrin is broken down by fibrinolytic enzymes, allowing normal healing. However, if this fibrinolytic activity is impaired, the fibrin persists and becomes organized into permanent fibrous adhesions. Factors that increase adhesion formation include tissue drying, excessive handling of tissues, foreign bodies (like sutures or powder from surgical gloves), and ischemia.

Clinical Complications of Intra-Abdominal Adhesions

These adhesions can lead to several serious clinical complications, including:

• Intestinal obstruction, which is the most common complication, occurring when adhesions kink, twist, or directly compress the bowel, preventing the normal passage of intestinal contents 1
• Chronic pelvic or abdominal pain, which can develop as adhesions restrict normal organ movement or pull on nerves
• Female infertility, which may result when adhesions distort pelvic anatomy, interfering with egg transport or implantation
• Complications during subsequent surgeries, as adhesions can obscure anatomy and increase the risk of inadvertent organ injury during dissection
• Reduced intestinal motility, resulting in chronic constipation or pseudo-obstruction syndromes

Prevention Strategies

Prevention strategies during surgery include:

• Minimizing tissue trauma
• Using minimally invasive techniques when possible
• Keeping tissues moist
• Using adhesion barriers like hyaluronic acid-based products to separate healing surfaces 1 Laparoscopic surgery may also reduce the risk of adhesion formation, although the evidence is still limited and more research is needed to fully understand its benefits and risks 1.

From the Research

Formation of Intra-Abdominal Adhesions

• Intra-abdominal adhesions are a common consequence of abdomino-pelvic surgery, radiation therapy, and inflammatory processes 2.
• They can form after most surgical procedures, with 80% to 90% of patients developing adhesions after abdominal surgery 3.
• The exact pathophysiologic process of adhesion formation is not fully understood, but it is associated with macrophage subtype 2 polarization and high mmp1 expression 3.

Clinical Complications of Intra-Abdominal Adhesions

• Intra-abdominal adhesions can lead to various clinical complications, including:
  • Small bowel obstruction 4, 3, 5
  • Chronic abdominal pain 4, 3, 2, 5
  • Infertility 4, 3, 5
  • Difficulty during reoperation 3
  • Abdominal distension, nausea, and abnormal bowel movement patterns 2
• These complications can be life-altering and may require further medical attention, including laparoscopic treatment 5.

Prevention and Treatment of Intra-Abdominal Adhesions

• Prevention of adhesion formation is a pressing goal in surgical research, with various strategies being explored, including the use of antiadhesive agents 4, 6.
• Laparoscopic treatment of adhesions is feasible in selected patients and may cause fewer newly formed adhesions 5.
• Further research is needed to understand the exact mechanisms of adhesion formation and to develop effective prevention and treatment strategies 3, 6.