About Hiatus Hernia
What is a hiatal hernia?
A hiatal hernia – also known as a hiatus hernia – is an anatomical condition where part of the stomach extends through the diaphragm and up into the chest cavity. Hiatal hernias occur in about 15% of the population, but cause symptoms in only a small number of those affected.
In the normal state of affairs, the esophagus, which is the tube down which food enters the stomach, goes down through the chest, and then through the diaphragm so that it can enter the abdomen. The hole in the diaphragm through which the esophagus passes is known as the esophageal hiatus; as soon as the esophagus has passed through this hole, it enters the stomach. In men and women with hiatal hernias, the hole in the diaphragm (the hiatal opening) is larger than it should be, and this allows a portion of the upper part of the stomach to move upwards through the hiatal opening and into the chest cavity.
Hiatal hernias are mostly seen in adults, and they have often developed over a long period of time.
What causes a hiatal hernia?
It’s not entirely clear why the esophageal hiatus should be larger than normal in certain people, but it is undoubtedly a fact that when the opening is larger than normal, the stomach does move upwards in to the chest cavity. Contributing factors thought to be associated with hiatal hernia include a shortening of the esophagus, possibly caused by damage and scar tissue as a result of acid reflux over a long period of time, which causes the esophagus to pull the stomach upwards. It’s also possible that an anatomical fault in the attachment of the esophagus to the diaphragm maybe responsible for the weakness of the structures around the hiatal opening.
Are there different types of hiatal hernias?
There are actually two types of hiatal or hiatus hernia, known as the sliding and the para-esophageal hiatal hernia.
Sliding hiatal hernias
These are the most common hiatal hernias, and the term refers to a condition in which part of the stomach and the junction between the esophagus and stomach protrude upwards into the chest cavity. All or part of the stomach, and the gastro-esophageal junction, may reside in the chest cavity permanently, or may only move up through the hiatal opening when a person swallows or indulges in heavy exercise. The protrusion off the stomach into the chest cavity occurs during swallowing because when a person swallows the muscles in the esophagus contract, and causes it to shorten; this inevitably pulls the stomach upwards.
The other kind of hiatal hernia, the para-esophageal hernia, is characterized by the fact that the gastro-esophageal junction remains where it should be located at the level of the diaphragm, the part of the stomach bulges into the chest cavity alongside the esophagus. These hernias remain inside the chest cavity tall times and are not affected by swallowing.
If a para-esophageal hernia is large, and especially if it happens to be compressing the esophagus, it may prevent food moving down into the stomach, and be responsible for food sticking in the esophagus after it has been swallowed. In these cases, it’s also not unknown for ulcers to form in the part of the stomach that is stuck in the chest cavity because of damage from stomach acid. However, large para-esophageal hernias are not especially common.
What are the symptoms of hiatal hernia?
Because the huge majority of hiatus hernias are sliding hiatus hernias, many of them do not even produce symptoms. However, the larger the hernia, the greater the chance of the person experiencing some symptoms. These include: acid reflux,gastroesophageal reflux disease (GERD), the various complications of GERD, and other clear symptoms such as nausea, vomiting, belching, and regurgitation.
All of these symptoms develop because the hernia stops the barrier between the esophagus and stomach (known as the lower esophageal sphincter) from working correctly, thereby allowing acid to reflux from the stomach into the esophagus.
Because men and women with GERD stand a higher chance of having a hiatal hernia than men and women who do not have GERD, we can clearly establish an association between hiatal hernias and GERD, but it remains uncertain why GERD can occur when no hiatal hernia is present. GERD is marked out by heartburn, regurgitation, and nausea.
How does a hiatal hernia cause GERD?
In general, acid is prevented from refluxing into the esophagus by abundant esophageal muscle where the esophagus joins the stomach. This is the lower esophageal sphincter. This muscle remains contracted for most of the time, as a safety valve which prevents acid from flowing upwards out of the stomach. It only relaxes when a person swallows, to allow food or drink to enter the stomach. It follows therefore that when this muscle is weak in some way, or not firmly attached to the diaphragm in the hiatal opening, the valve will not work effectively, and the stomach or stomach contents may flow or move upwards into the chest cavity.
There is another safety mechanism which operates at the junction of the esophagus and stomach just below the gastroesophageal junction. There is some tissue just below the gastroesophageal junction which acts as a valve. Normally, the esophagus and the stomach at a sharp angle, and there’s a thin piece of tissue located in this angle, composed partly of esophageal tissue and partly of stomach wall, which forms a valve when pressure increases in the stomach. This might, for example, include conditions of strenuous exercise.
In a person with a hiatal hernia, some changes take place in the valve-like tissue. Because the sphincter muscle has moved up into the chest but the diaphragm remains in its normal position, the pressure which is normally exerted by the diaphragm over the sphincter,g and the pressure produced by the sphincter itself no longer correctly located, which means that the total pressure in the astroesophageal junction is much lower than it should be.
In addition, when the gastroesophageal junction and stomach move up into the chest cavity when a person swallows, the angle where the esophagus enters the stomach is much less acute than it should be, so in effect the valve control is lost. Both of these changes are responsible for permitting acid reflux.
Hiatal hernia diagnosis
Very often a hiatal hernia is only found when investigations for abdominal pain or discomfort or other symptoms takes place. Either an x-ray or an endoscopy will reveal the presence of hiatal hernia because it appears a separate sac of tissue which lies between the esophagus and stomach. It’s bounded on one side by the lower esophageal sphincter, and on the other by the diaphragm. It may only be visible when a person swallows however.
Hiatal hernia treatment
Treatment of a large para-esophageal hernia which is producing symptoms will involve surgery. In this operation, the stomach is repositioned in the abdomen, so that the esophageal hiatus is smaller, and the esophagus will be firmly attached to the diaphragm. Besides restoring normal anatomy, this will also restore normal function.
Sliding hiatal hernias are not noted for causing problems themselves, but often contribute to acid reflux. This means that treatment is often the same as it is for men and women with GERD. When GERD is serious, or there are complications, or it doesn’t respond to medication, surgery may be considered an option. In the surgery, the hiatal hernia will be dealt with in a way similar to that for the repair of para-esophageal hernias. In addition, surgeons may opt to wrap part of the upper stomach around the lower esophageal sphincter so as to increase the pressure at the sphincter and thereby help to prevent acid reflux.