Hiatal hernia

Definition
A hiatal hernia is a protrusion of part of the stomach from its normal position in the abdomen through the diaphragm.

Anatomy
The diaphragm is the muscle that separates the chest cavity from the abdominal cavity. The esophagus (the tube that connects the throat and stomach) passes through the diaphragm through an opening called the hiatus. The lower esophageal sphincter is the valve between the esophagus and the stomach.

Causes/associated factors
When the muscles that support the hiatus weaken, the stomach can herniate (protrude) into the chest cavity, causing a hiatal hernia. Sometimes, hiatal hernias are related to increased pressure in the abdominal cavity, which can be caused by:
coughing
vomiting
straining during a bowel movement
sudden physical exertion (lifting something heavy, for example)
an inherited weakness in the muscular ring of the diaphragm, located near the lower esophagus
Pregnancy, obesity, increased fluid in the abdomen, tight clothing or abdominal injury can also lead to hiatal hernias. Some infants are born with a hiatal hernia, and many people over age 50 develop small hiatal hernias.

Sliding or type I hiatal hernias often go undetected or remain uncomplicated. Excessively large hiatal hernias, called paraesophageal hernias, are less common and more serious because nearly all of the stomach pushes through the diaphragm in the chest cavity.


Signs/symptoms
Most hiatal hernias do not cause symptoms. If symptoms appear, they may include:
difficulty swallowing
upper abdominal discomfort or fullness
chest pain
heartburn
belching
gas
regurgitation
acid reflux (backflow of stomach acid into the esophagus, also known as gastroesophageal reflux) that may worsen when you bend over or lie down (It's thought that hiatal hernias are associated with acid reflux because they allow stomach acid to be held above the opening of the diaphragm, making it easy for the acid to flow back into the esophagus.)

Diagnosis
Diagnosis is often based on your symptoms and a physical exam. The doctor typically evaluates areas other than the gastrointestinal tract first if you have symptoms, however. For example, if you have chest pain, the doctor will routinely check your heart before attributing the pain to a hiatal hernia. To rule out other possible gastrointestinal conditions, you may need one or more of the following tests:
Upper gastrointestinal (GI) series: This special X-ray study uses a contrast material (usually barium) to outline the esophagus, stomach and upper part of the small intestine.

Upper GI endoscopy: The doctor directly views the lining of your esophagus with an instrument called a fiberoptic endoscope (a tube equipped with a camera lens and light). This procedure is especially helpful in diagnosing hiatal hernias because the scope can flex or bend backward. Small tissue samples can also be removed during this procedure for further examination.

Bernstein test: The doctor drips a mild acid into your esophagus through a tube in your throat. The test confirms acid reflux if symptoms of heartburn quickly appear with use of the mild acid and then disappear when a salt solution is placed in the lower esophagus.

Esophageal manometric test: This helps the doctor decide if the lower esophageal sphincter is working properly by taking pressure measurements near the valve.

pH testing: If the diagnosis is still uncertain, your doctor may use 24-hour esophageal pH testing to measure the acid levels inside your esophagus during meals, activity and sleep.
Other testing may also be done, such as a chest X-ray, ultrasound of the abdomen or additional imaging studies.


Treatment
In mild cases, hiatal hernias don't require treatment. To help you relieve symptoms and prevent complications, consider the following lifestyle adjustments.
Avoid foods that may reduce the muscle tone of the sphincter area between the esophagus and stomach. Foods to avoid include chocolate, coffee, tea, cola, alcohol, peppermint, spearmint, and fried or fatty foods. If the lining of your esophagus is irritated, avoid citrus fruits, tomato products, pepper and carbonated beverages.

Eat smaller meals throughout the day, rather than two or three large meals. Don't eat anything for at least two to three hours before going to bed.

Eat slowly rather than gulping. This reduces air swallowing and belching, which can cause reflux of stomach acids.

If you're overweight, lose the extra pounds. Your doctor can help you design an appropriate weight loss plan.

If you smoke, quit.

Raise the head of your bed about 6 inches by placing phone books or wood blocks under the legs of your bed.
Medication
You can use antacids occasionally to neutralize stomach acid and stop heartburn. It's not safe to take antacids on a regular basis, however. Long-term use may cause diarrhea, change the way your body breaks down calcium, and create magnesium retention, which is risky if you have kidney disease. Don't take antacids for more than three weeks without consulting your doctor.

Over-the-counter H2 receptor antagonists (acid blockers) are also available for occasional relief. If you have chronic acid reflux, your doctor may prescribe these same acid blockers in a prescription-strength formula (such as cimetidine, famotidine, ranitidine or nizatidine) to decrease the production of stomach acid. Proton pump inhibitors such as lansoprazole and omeprazole may be recommended if acid blockers don't provide relief. Over-the-counter omeprazole (brand name Prilosec OTC) is available at a lower dose.

Your doctor may also prescribe medication to tighten the sphincter or valve between the esophagus and stomach, which can help your stomach to empty more quickly and prevent acid reflux upward into the esophagus. These drugs include bethanechol and metoclopramide.

Surgical repair
Nissen fundoplication (surgery to repair a hiatal hernia) may be necessary if the hernia is large, may strangulate (constrict or cut off) your stomach, or causes chronic acid reflux. Surgery may also be needed if you have severe symptoms that don't respond to conventional treatment or you develop complications.

With fundoplication, the doctor closes the weakness in the hiatus and keeps the stomach in its natural place. The procedure may be done through an incision in the abdomen or chest or through a laparascope (a thin, flexible tube equipped with a camera lens and light used to see the inside of a hollow organ or cavity). To reduce acid reflux, the upper part of the stomach may be wrapped around the esophagus.


Complications
If a hiatal hernia causes chronic acid reflux, you may develop:
narrowing and scarring of the esophagus, (Barrett's esophagus) which makes it difficult to swallow and may increase your risk of cancer
bleeding from the esophagus, sometimes massive or progressing to shock
pneumonia, if you inhale stomach contents into the lungs
irritation or ulcerations on the lining of the esophagus, which may increase the risk of cancer
Severe hiatal hernias, which are less common, can cause obstruction, strangulation, perforation and hemorrhage.


Pregnancy-specific information
The intermittent but lingering increase in abdominal pressure associated with pregnancy can cause hiatal hernias. These hernias may cause vomiting, as well as stomach or abdominal pain or bleeding. Even with symptoms, complications are uncommon. When necessary, surgical repair can be done during pregnancy.

Senior-specific information
Older adults are susceptible to the same potentially serious complications described above.

Prevention
To prevent a hiatal hernia, don't smoke and avoid caffeine and alcohol. If you're overweight, lose the extra pounds.