Intestinal Adhesions

How adhesions form

The organs in the abdomen are covered by a smooth, slippery lining, the peritoneum, which lets them slide past each other. When this lining is injured, by surgery, infection or inflammation, the body lays down fibrin as part of healing. If the fibrin is not broken down, it organizes into bands of scar tissue that tether structures together.

Adhesions can form within hours to days of surgery and mature over weeks. They may be thin films or thick, tough bands.

Causes and risk factors

• Abdominal and pelvic surgery: the most common cause, especially open surgery and operations on the bowel, appendix, uterus and ovaries
• Infections: appendicitis that ruptured, peritonitis, pelvic inflammatory disease
• Endometriosis
• Inflammatory bowel disease, particularly Crohn's disease
• Radiation therapy to the abdomen or pelvis
• Peritoneal dialysis

Laparoscopic (keyhole) surgery generally causes fewer adhesions than open surgery.

Symptoms

Most adhesions are silent. When they cause problems:

Bowel obstruction

Adhesions can kink, twist or squeeze the small intestine, causing a bowel obstruction. This causes:

• crampy, wave-like belly pain
• bloating and a swollen belly
• nausea and vomiting
• inability to pass gas or stool
• loud bowel sounds

If the blood supply to the bowel is cut off (strangulation), pain becomes constant and severe, and fever and a racing heart develop. This is a surgical emergency. See adhesive small bowel obstruction.

Chronic pain

Some people have recurring belly or pelvic pain linked to adhesions, often worse with movement, exercise or after eating. The link is debated, because many people with adhesions have no pain.

Infertility

Pelvic adhesions can block or distort the fallopian tubes and ovaries, reducing fertility, and are a cause of female infertility.

Diagnosis

Adhesions themselves are not seen on X-rays, ultrasound or CT. Doctors diagnose them by:

• history: previous surgery, symptoms
• CT scan: in suspected obstruction, shows dilated bowel loops, a transition point and signs of strangulation
• Water-soluble contrast study: contrast swallowed and followed by X-ray predicts whether an obstruction will resolve without surgery and may help it resolve
• Laparoscopy: the only way to see adhesions directly
• Hysterosalpingography or laparoscopy for fertility evaluation

Treatment

Adhesive bowel obstruction

• Non-surgical management succeeds in most partial obstructions without strangulation: nothing by mouth, IV fluids, a tube through the nose to empty the stomach (nasogastric tube), and pain control. Improvement usually occurs within 2 to 3 days
• Surgery (adhesiolysis): cutting the adhesions, laparoscopically or through open surgery, for complete obstruction, strangulation, or obstruction not resolving within about 3 to 5 days. Damaged bowel may need to be removed

Chronic pain and infertility

• laparoscopic adhesiolysis may help selected people, but adhesions often reform
• pain management, including physical therapy and nerve pain medicines
• fertility treatments, including IVF, when tubes are blocked

Prevention

Surgeons reduce adhesions by:

• using laparoscopic techniques when possible
• handling tissues gently and limiting bleeding
• avoiding talc from gloves and foreign material
• using adhesion barrier films or gels in some operations

There is nothing a patient can do to prevent adhesions after surgery, but knowing your surgical history helps doctors recognize obstruction quickly.

Outlook

Most people with adhesions never have problems. After one adhesive obstruction, the chance of another is higher, and some people have repeated episodes. Each new surgery can create new adhesions, so doctors weigh the benefits of surgery carefully.

Frequently asked questions

What are intestinal adhesions?

They are bands of scar tissue that form inside the abdomen, connecting loops of bowel to each other or to other organs or the belly wall. They usually form after abdominal or pelvic surgery, and also after infection, endometriosis or radiation.

What are the symptoms of bowel adhesions?

Most adhesions cause no symptoms. When they do, they can cause chronic belly pain or bowel obstruction, with cramping pain, bloating, vomiting and inability to pass gas or stool. Pelvic adhesions can also contribute to infertility.

Can adhesions show up on a CT scan?

Adhesions themselves usually do not show on CT, ultrasound or MRI. A CT scan can show a bowel obstruction and point to adhesions as the likely cause. Laparoscopy is the only way to see them directly.

Can adhesions go away on their own?

Mature adhesions do not usually disappear. Many cause no trouble and need no treatment. Bowel obstructions caused by adhesions often resolve without surgery, but surgery may be needed if they do not or if the bowel's blood supply is at risk.

How are adhesions treated?

Asymptomatic adhesions need no treatment. Adhesive bowel obstruction is first treated with bowel rest, IV fluids and a nasogastric tube; surgery to cut the adhesions is done if this fails or strangulation is suspected. Selected people with chronic pain or infertility may benefit from laparoscopic adhesiolysis.