Diseases and Disorders
Gastroesophageal Reflux Disease (GERD)
GERD is a condition of abnormal exposure of the esophagus to refluxing gastric contents. Approximately 20% of the population experience weekly symptoms of heartburn or regurgitation, and GERD is the costliest gastrointestinal disorder in the United States. Tens of billions of dollars are spent each year on gastric acid suppression medications, yet we continue to witness a rise in the complications of the disease.
- International reputation in the diagnosis and treatment of GERD, including the pioneering development of pH testing and refinement of modern antireflux surgery
- Dedicated esophageal diagnostic lab run by USC thoracic surgeons with integrated esophageal function testing and endoscopy
- State-of- the-art diagnostic technology that allows individualization of the evaluation to the patient’s unique circumstances
- Tailoring of the antireflux operation to the patient’s disease and physiology
- Extensive experience in re-operative procedures and remedial operations for GERD
- High-volume referral center for GERD with knowledgeable thoracic surgeons, nurses, and staff
Mechanism of the Disease
Abnormal exposure of the esophagus to gastric contents occurs by loss of the barrier between the esophagus and stomach. This barrier is comprised of two components, the lower esophageal sphincter (LES) and the diaphragm muscles that surround the esophagus as it passes from the chest to the abdomen (the hiatus). Over time, the LES can become permanently destroyed and result in a short length or low resting pressure, allowing gastric contents to reflux up into the esophagus. In addition, the diaphragm muscles surrounding the esophagus can become lax, allowing the formation of a hiatal hernia. This allows the stomach to partially migrate into the chest and puts the LES at a mechanical disadvantage. [FIGURE]
Other factors that contribute to GERD are the emptying function of the stomach and the clearing ability of the esophagus. If the stomach does not empty properly, distension may occur and result in stretching out of the LES, with resultant loss of competence. This can occur periodically when one overeats or eats fatty or greasy food that takes a long time to digest, and in some individuals this delayed gastric emptying can become permanent. Further, when gastric contents reflux into the esophagus, the normal esophagus is able to contract and clear the refluxed contents rapidly back into the stomach with peristaltic waves. However, if esophageal motility is weak or uncoordinated, refluxed contents can collect in the esophagus for a prolonged period of time. This can lead to prolonged exposure of the esophagus to gastric contents with resultant tissue injury.
There is also a direct link between GERD and pulmonary diseases such as adult-onset asthma or pulmonary fibrosis. Refluxed gastric contents can get up into the throat and can enter the airways and lungs to cause irritation or damage. This can be obviously manifested as episodes of aspiration and pneumonia or it can occur silently with progressive breathing problems. Careful evaluation for GERD in these situations and intervention can help prevent further complications, and may even reverse many of these pulmonary symptoms.
Symptoms of GERD are typically heartburn and regurgitation, and sometimes can include difficulty passing food down the esophagus. To objectively diagnose GERD, there are several tests that provide different types of information to the thoracic surgeon. Together, these tests complement one another to give an overall assessment of the degree of reflux that is present, as well as provide important physiologic information that will assist in the tailoring of the treatment. All of these tests have been developed with a stringent protocol specific to the USC Center for Esophageal Disorders with significant emphasis placed on the quality and accuracy of the information obtained. For this reason, similar tests that are offered at other hospitals are generally not relied upon.
Ambulatory pH Testing
The most objective way to diagnose GERD is to document pathologic exposure of the esophagus to refluxing gastric juice. This is done by utilizing a small pH probe that is positioned in the distal esophagus for 24 to 48 hours while the patient is at home or work performing their usual activities. This form of ambulatory pH testing was pioneered by Dr. Tom DeMeester of USC, and the scoring system that was developed bears his name. pH testing allows the thoracic surgeon to quantify the degree of reflux that is present, which allows the tailoring of the patient’s treatment.[FIGURE] At the present time we offer an array of several different types of pH monitoring systems, and the appropriate one is selected by the thoracic surgeon to individualize the diagnostic workup to the patient’s needs. Standard catheter based pH probes are thin tubes that are passed down the nose and swallowed into the esophagus and subsequently attached to a small computer receiver. Alternatively, a wireless pH probe (Bravo®) can be clipped into the esophagus and the data is transmitted wirelessly to the computer receiver. Finally, for patients with predominantly upper respiratory or upper esophageal symptoms of reflux, a pH probe is available for monitoring the pharynx (Restech®). Other technology available includes impedance monitoring, which allows the monitoring of non-acid fluid into the esophagus.
Esophageal manometry is a diagnostic test that uses tiny transducers or receivers that are integrated into a thin catheter or tube that is inserted into the esophagus to measure pressure. This device is used to measure the LES length and resting pressure, its ability to relax with swallowing, the contractile strength and coordination of the esophageal body, and the upper esophageal sphincter characteristics.[FIGURE] There are several manometry catheters that are available at the USC Center for Esophageal Disease, and the most appropriate one will be selected by the patient’s thoracic surgeon appropriate for the circumstances. Standard manometry catheters may be used, or high-resolution catheters (ManoScan®). Additionally, impedance technology may be necessary to further monitor how effective the esophagus can clear swallowed liquids.
A video esophagram is a radiologic study that is performed by dedicated radiologists with a focus in esophageal disorders. During this examination, the patient is asked to swallow barium liquid 5 times and soft food 2 times while a special x-ray machine videotapes the clearance of the swallowed material. This gives additional information regarding the function of the esophagus. It also provides information regarding any anatomic abnormalities that may be present, such as strictures, a hiatal hernia, or a diverticulum or outpouching of the esophagus.
Upper endoscopy is a critical component of assessing a patient for GERD, and USC thoracic surgeons are keenly interested in performing this procedure to visualize the esophagus and stomach for evidence of injury related to GERD. In addition, anatomic details critical for pre-operative planning may be observed during this procedure, such as strictures or a hiatal hernia. Endoscopy also allows the thoracic surgeon to assess patients for potential reasons for anemia related to a paraesophageal hernia. Finally, GERD can cause a pre-cancerous condition known as Barrett’s esophagus and even cancer itself, so the endoscopic examination allows the thoracic surgeon to ensure that these potentially life-threatening complications of GERD have not occurred.
Broadly speaking, the treatment of GERD can be divided into medical and surgical options. The medical option involves acid suppression medications, and most patients have attempted this by the time they are seen in consultation. In many patients, these medications alleviate the symptom of heartburn quite well, but regurgitation remains a problem. This is due to the mechanical loss of the barrier between the esophagus and stomach, and there is no medication that can fix this type of problem. Furthermore, many patients are apprehensive about taking acid suppression medications for long periods of time due to potential long term consequences of these drugs.
Surgical options involve reconstructing the barrier between the esophagus and stomach by using a redundant portion of the stomach called the fundus. The fundus is used to create a new physiologic barrier to prevent reflux of gastric contents up into the esophagus while allowing swallowed liquid and food to pass unabated. This operation is known as a fundoplication, and there are several different types. The specific fundoplication performed is determined by the thoracic surgeon and is tailored to the individual’s anatomy and esophageal function. The most common operation is the Nissen fundoplication, which is a 360 degree fundoplication, but in some instances a partial fundoplication such as a Toupet is more appropriate.[FIGURE] In addition, some patients develop a foreshortened esophagus due to chronic damage from GERD. In these situations, the surgeon may need to lengthen the esophagus by elongating it with a portion of the stomach, and this procedure is known as a Collis gastroplasty. Finally, if the diaphragm hiatus is found to be too large and there is a risk of another hiatal hernia, the thoracic surgeon will reinforce the hiatal closure with a form of absorbable mesh. Just as surgeons fix abdominal wall or groin hernias with mesh to strengthen the repair, thoracic surgeons apply this principle to the repair of hiatal hernias.
Over the years USC thoracic surgeons have been witnessing increasing numbers of patients referred for remedial antireflux surgery, whose operations were done elsewhere. These situations add more complexity and the potential for greater complications than patients who have never had antireflux surgery, and the experience of the surgeon in evaluating the problem and fixing it is even more critical. It is testimony to the collective experience of this group that when complications or problems arise following antireflux surgery, patients are sent to USC for further evaluation and treatment.
USC thoracic surgeons have accumulated one of the largest experiences in the country in antireflux surgery for GERD, with well over 1,000 operations of this type performed since 1990. Following surgery, patients should expect to obtain relief of classic symptoms of GERD such as heartburn and regurgitation, and they should not require any more acid suppression medications. Many patients report nearly instantaneous improvement in these symptoms after this operation. Other symptoms, such as pulmonary manifestations of GERD, usually take longer to improve since the inflammation of the airways subsides more slowly.
The most common side effect of antireflux surgery is the inability to belch or vomit due to the reconstructed barrier between the stomach and esophagus. If patients swallow a lot of air while eating, this air can lead to some minor bloating or increased flatulence. In general, however, this does not bother patients. The inability to vomit is not dangerous and complications from this are extremely rare. Temporary difficulty swallowing solid food can occur following antireflux surgery due to the muscle swelling around the esophagus and stomach resulting from the operation. This resolves over a short period of time and it is rarely an issue long term.
USC surgeons have followed their patients long term following antireflux surgery, and the durability of the operation appears to be excellent. Many of the pioneering technical details of the operation have been refined at USC, and these principles have been adopted by other surgeons around the world.
For the past few decades, endoscopic techniques have been attempted a means of providing a less invasive treatment for GERD. The lure of an incisionless procedure to reproduce what is done in surgery has been appealing. However, as of yet there has not been a convincing or effective endoscopic treatment for reconstructing the barrier between the esophagus and stomach, but surgeons at USC continue to evaluate newer endoscopic therapies that are emerging.
Another area of research being done at USC is the use of an artificial esophageal sphincter called the Torax®. This is essentially a small bracelet composed of tiny magnets that is placed around the defective lower esophageal sphincter through a laparoscopic operation. It is customized to the individual patient and allows swallowed liquid and food to pass through into the stomach, but reduces the ability to reflux gastric contents up into the esophagus.