Mechanism of the Disease
Abnormal exposure of the oesophagus to stomach contents occurs by loss of the barrier between the oesophagus and stomach. This barrier is comprised of two components, the lower oesophageal sphincter (LOS) and the diaphragm muscles that surround the oesophagus as it passes from the chest to the abdomen (the hiatus). Over time, the LOS can become permanently destroyed and result in a short length or low resting pressure, allowing stomach contents to reflux up into the oesophagus. In addition, the diaphragm muscles surrounding the oesophagus can become lax, allowing the formation of a hiatal hernia. This allows the stomach to partially migrate into the chest and puts the LOS at a mechanical disadvantage.
Other factors that contribute to GORD are the emptying function of the stomach and the clearing ability of the oesophagus. If the stomach does not empty properly, distension may occur and result in stretching out of the LOS, 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 oesophagus, the normal oesophagus is able to contract and clear the refluxed contents rapidly back into the stomach with peristaltic waves. However, if oesophageal motility is weak or uncoordinated, refluxed contents can collect in the oesophagus for a prolonged period of time. This can lead to prolonged exposure of the oesophagus to gastric contents with resultant tissue injury.
There is also a direct link between GORD and lung diseases such as 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, cough, hoarseness or sinusitis. Careful evaluation for GORD in these situations and intervention can help prevent further complications, and may even reverse many of these pulmonary symptoms.
Symptoms of GORD are typically heartburn and regurgitation, and sometimes can include difficulty passing food down the oesophagus. To objectively diagnose GORD, there are several tests that provide different types of information to the 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 physiological information that will assist in the tailoring of the treatment.Ambulatory pH Testing
The most objective way to diagnose GORD is to document abnormal exposure of the oesophagus to refluxing stomach juices. This is done by utilising a small pH probe that is positioned in the oesophagus 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 at the University of Southern California in Los Angeles, the institution where Mr Kohn undertook his fellowship training. pH testing allows the surgeon to quantify the degree of reflux that is present, which allows the tailoring of the patient’s treatment. In addition to standard single-sensor pH testing, we also perform oesophageal impedance monitoring, tests which allows the monitoring of non-acid fluid into the oesophagus.Oesophageal Manometry Oesophageal 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 oesophagus to measure pressure. This device is used to measure ability of the LOS to relax with swallowing, the contractile strength and coordination of the oesophageal body, and the upper oesophageal sphincter characteristics.Video oesophagram
A video oesophagram is a X-ray study that is performed by radiologists. During this examination, the patient is asked to swallow barium liquid while a special x-ray machine videotapes the clearance of the swallowed material. This gives additional information regarding the function of the oesophagus. 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 oesophagus.Gastroscopy Gastroscopy
is a critical component of assessing a patient for GORD, and MUGISG surgeons are keenly interested in performing this procedure to visualise the oesophagus and stomach for evidence of injury related to GORD. In addition, details critical for pre-operative planning may be observed during this procedure, such as strictures or a hiatal hernia. Endoscopy also allows the surgeon to assess patients for potential reasons for anaemia related to a para-oesopahgeal hernia. Finally, GORD can cause a pre-cancerous condition known as Barrett’s oesophagus and even cancer itself, so the endoscopic examination allows the surgeon to ensure that these potentially life-threatening complications of GORD have not occurred.
Broadly speaking, the treatment of GORD 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 oesophagus 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 oesophagus and stomach by using a portion of the stomach called the fundus. The fundus is used to create a new physiological barrier to prevent reflux of gastric contents up into the oesophagus 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 surgeon and is tailored to the individual’s anatomy and oesophageal 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. In addition, some patients develop a foreshortened oesophagus due to chronic damage from GORD. In these situations, the surgeon may need to lengthen the oesophagus 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 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, our surgeons apply this principle to the repair of hiatal hernias.
Following surgery, patients should expect to obtain relief of classic symptoms of GORD 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 GORD, usually take longer to improve since the inflammation of the airways subsides more slowly.
The most common side effect of anti-reflux surgery is the inability to belch or vomit due to the reconstructed barrier between the stomach and oesophagus. 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 anti-reflux surgery due to the muscle swelling around the oesophagus and stomach resulting from the operation. This resolves over a short period of time and it is rarely an issue long term.