Congenital diaphragmatic hernia

Definition

Hernia is a general term used to describe a bulge or protrusion of an organ through the structure or muscle that usually contains it.

Description

There are many different types of hernias. The most familiar type are those that occur in the abdomen, in which part of the intestines protrude through the abdominal wall. This may occur in different areas and, depending on the location, the hernia is given a different name.

An inguinal hernia appears as a bulge in the groin and may come and go depending on the position of the person or their level of physical activity. It can occur with or without pain. In men, the protrusion may descend into the scrotum. Inguinal hernias account for 80% of all hernias and are more common in men.

Femoral hernias are similar to inguinal hernias but appear as a bulge slightly lower. They are more common in women due to the strain of pregnancy.

A ventral hernia is also called an incisional hernia because it generally occurs as a bulge in the abdomen at the site of an old surgical scar. It is caused by thinning or stretching of the scar tissue, and occurs more frequently in people who are obese or pregnant.

An umbilical hernia appears as a soft bulge at the navel (umbilicus). It is caused by a weakening of the area or an imperfect closure of the area in infants. This type of hernia is more common in women due to pregnancy, and in Chinese and black infants. Some umbilical hernias in infants disappear without treatment within the first year.

A hiatal or diaphragmatic hernia is different from abdominal hernias in that it is not visible on the outside of the body. With a hiatal hernia, the stomach bulges upward through the muscle that separates the chest from the abdomen (the diaphragm). This type of hernia occurs more often in women than in men, and it is treated differently from other types of hernias.

Causes & symptoms

Most hernias result from a weakness in the abdominal wall that either develops or that an infant is born with (congenital). Any increase in pressure in the abdomen, such as coughing, straining, heavy lifting, or pregnancy, can be a considered causative factor in developing an abdominal hernia. Obesity or recent excessive weight loss, as well as aging and previous surgery, are also risk factors.

Most abdominal hernias appear suddenly when the abdominal muscles are strained. The person may feel tenderness, a slight burning sensation, or a feeling of heaviness in the bulge. It may be possible for the person to push the hernia back into place with gentle pressure, or the hernia may disappear by itself when the person reclines. Being able to push the hernia back is called reducing it. On the other hand, some hernias cannot be pushed back into place, and are termed incarcerated or irreducible.

A hiatal hernia may also be caused by obesity, pregnancy, aging, or previous surgery. About 50% of all people with hiatal hernias do not have any symptoms. If symptoms exist they will include heartburn, usually 30-60 minutes following a meal. There may be some mid chest pain due to gastric acid from the stomach being pushed up into the esophagus. The pain and heartburn are usually worse when lying down. Frequent belching and feelings of abdominal fullness may also be present.

Diagnosis

Generally, abdominal hernias need to be seen and felt to be diagnosed. Usually the hernia will increase in size with an increase in abdominal pressure, so the doctor may ask the person to cough while he or she feels the area. Once a diagnosis of an abdominal hernia is made, the doctor will usually send the person to a surgeon for a consultation. Surgery provides the only cure for a hernia through the abdominal wall.

With a hiatal hernia, the diagnosis is based on the symptoms reported by the person. The doctor may then order tests to confirm the diagnosis. If a barium swallow is ordered, the person drinks a chalky white barium solution, which will help any protrusion through the diaphragm show up on the x ray that follows. Currently, a diagnosis of hiatal hernia is more frequently made by endoscopy. This procedure is done by a gastroenterologist (a specialist in digestive diseases). During an endoscopy the person is given an intravenous sedative and a small tube is inserted through the mouth, then into the esophagus and stomach where the doctor can visualize the hernia. The procedure takes about 30 minutes and usually causes no discomfort. It is done on an outpatient basis.

Treatment

Once an abdominal hernia occurs it tends to increase in size. Some patients with abdominal hernias wait and watch for a while prior to choosing surgery. In these cases, they must avoid strenuous physical activity such as heavy lifting or straining with constipation. They may also wear a truss, which is a support worn like a belt to keep a small hernia from protruding. People can tell if their hernia is getting worse if they develop severe constant pain, nausea and vomiting, or if the bulge does not return to normal when lying down or when they try to gently push it back in place. In these cases they should consult with their doctor immediately. But, ultimately, surgery is the treatment in almost all cases.

There are risks to not repairing a hernia surgically. Left untreated, a hernia may become incarcerated, which means it can no longer be reduced or pushed back into place. With an incarcerated hernia the intestines become trapped outside the abdomen. This could lead to a blockage in the intestine. If it is severe enough it may cut off the blood supply to the intestine and part of the intestine might actually die.

When the blood supply is cut off, the hernia is termed "strangulated." Because of the risk of tissue death (necrosis) and gangrene, and because the hernia can block food from moving through the bowel, a strangulated hernia is a medical emergency requiring immediate surgery. Repairing a hernia before it becomes incarcerated or strangulated is much safer than waiting until complications develop.

Surgical repair of a hernia is called a herniorrhaphy. The surgeon will push the bulging part of the intestine back into place and sew the overlying muscle back together. When the muscle is not strong enough, the surgeon may reinforce it with a synthetic mesh.

Surgery can be done on an outpatient basis. It usually takes 30 minutes in children and 60 minutes in adults. It can be done under either local or general anesthesia and is frequently done with a laparoscope. In this type of surgery, a tube that allows visualization of the abdominal cavity is inserted through a small puncture wound. Several small punctures are made to allow surgical instruments to be inserted. This type of surgery avoids a larger incision.

A hiatal hernia is treated differently. Medical treatment is preferred. Treatments include:

• Avoiding reclining after meals
• Avoiding spicy foods, acidic foods, alcohol, and tobacco
• Eating small, frequent, bland meals
• Eating a high-fiber diet.

There are also several types of medications that help to manage the symptoms of a hiatal hernia. Antacids are used to neutralize gastric acid and decrease heartburn. Drugs that reduce the amount of acid produced in the stomach (H2 blockers) are also used. This class of drugs includes famotidine (sold under the name Pepcid), cimetidine (Tagamet), and ranitidine (Zantac). Omeprazole (Prilosec) is not an H2 blocker, but is another drug that suppresses gastric acid secretion and is used for hiatal hernias. Another option may be metoclopramide (Reglan), a drug that increases the tone of the muscle around the esophagus and causes the stomach to empty more quickly.

Alternative treatment

There are alternative therapies for hiatal hernia. Visceral manipulation, done by a trained therapist, can help replace the stomach to its proper positioning. Other options in addition to H2 blockers are available to help regulate stomach acid production and balance. One of them, deglycyrrhizinated licorice (DGL), helps balance stomach acid by improving the protective substances that line the stomach and intestines and by improving blood supply to these tissues. DGL does not interrupt the normal function of stomach acid.

As with traditional therapy, dietary modifications are important. Small, frequent meals will keep pressure down on the esophageal sphincter. Also, raising the head of the bed several inches with blocks or books can help with both the quality and quantity of sleep.

Prognosis

Abdominal hernias generally do not recur in children but can recur in up to 10% of adult patients. Surgery is considered the only cure, and the prognosis is excellent if the hernia is corrected before it becomes strangulated.

Hiatal hernias are treated successfully with medication and diet modifications 85% of the time. The prognosis remains excellent even if surgery is required in adults who are in otherwise good health.

Prevention

Some hernias can be prevented by maintaining a reasonable weight, avoiding heavy lifting and constipation, and following a moderate exercise program to maintain good abdominal muscle tone.

Key Terms

Endoscopy

A diagnostic procedure in which a tube is inserted through the mouth, into the esophagus and stomach. It is used to visualize various digestive disorders, including hiatal hernias.

Herniorrhaphy

Surgical repair of a hernia.

Incarcerated hernia

A hernia that can not be reduced, or pushed back into place inside the intestinal wall.

Reducible hernia

A hernia that can be gently pushed back into place or that disappears when the person lies down.

Strangulated hernia

A hernia that is so tightly incarcerated outside the abdominal wall that the intestine is blocked and the blood supply to that part of the intestine is cut off.

Further Reading

For Your Information

Books

• Bare, Brenda G., and Suzanne C. Smeltzer. Brunner and Suddarth's Textbook of Medical-Surgical Nursing. 8th edition. Philadelphia: Lippincott-Raven Publishers, 1996.
• Polaske, Arlene L., and Suzanne E. Tatro. Luckmann's Core Principles and Practice of Medical Surgical Nursing. Philadelphia: W.B. Saunders Company, 1996.

  Periodicals

• Kingsley, A.N., I.L. Lichtenstein, and W.K. Sieber. "Common Hernias In Primary Care." Patient Care (April 1990): 98-119.
• Leung, A.K.C., W.L. Robson, and A.L. Wong. "Diagnosis At a Glance." Emergency Medicine (January 1993): 3536.
• Lipsyte, R. "Pig-out Penalty... Hiatal Hernia." American Health: Fitness Of Body And Mind (November, 1994): 49-50.
• Spiro, H.M. "Hiatus Hernia and Reflux Esophagitis." Hospital Practice (January, 1994): 51-66.

Gale Encyclopedia of Medicine. Gale Research, 1999.