Definition and Overview
Hernia is a general medical term used to describe a condition in which fatty tissue or an internal organ squeezes through a weak spot in the supporting muscle or connective tissue. If a part of the stomach pushes through the oesophageal hiatus (small opening in the diaphragm) and rests in the chest cavity, the condition is called a hiatal hernia. Other types of hernias are incisional (caused by a surgical incision), femoral (outer groin), inguinal (inner groin), and umbilical (belly button) hernias.
The diaphragm is a dome-shaped muscle that separates the chest from the abdomen. When a person takes a deep breath, the diaphragm contracts and flattens in order to pull air into the lungs. The hiatus is found on the left diaphragm and serves as a gateway for the oesophagus, which carries food and liquid to the stomach.
The enlargement of the hiatus is often associated with heredity, obesity, or straining at stool. The enlarged size of the hole causes the upper portion of the stomach to move up.
There are two types of hiatal hernias, namely:
Sliding hiatal hernia – The more common type that accounts for up to 95% of all hiatal hernias. It occurs when the stomach and oesophagus slide back and forth into the chest. Sliding hernias are usually not a cause for concern because they tend to be very small and do not pose any serious threat to patients' health. Most also do not require treatment.
Fixed hiatal hernia – Also called paraesophageal hernia, a fixed hiatal hernia occurs when part of the stomach pushes through the diaphragm and stays there. Although most cases are not serious, the condition can sometimes block the blood flow to the stomach, resulting in a medical emergency.
Causes of Condition
The most common cause of hiatal hernia is the weakening of the muscle tissue that is supposed to keep the stomach in its proper place. This causes the upper part of the stomach to move and bulge up through the diaphragm. The reasons why muscle tissue weakens are not yet fully understood. However, age-related changes in the diaphragm may play a role. Other possible causes include:
A congenital disorder in which an infant is born with an unusually large hiatus
Injury to the area
Intense, persistent pressure caused by lifting heavy objects, vomiting, coughing, and straining during bowel movements
Ascites, or the collection of fluid in the abdominal cavity due to liver failure
The risk of hiatal hernia is higher among individuals who are:
Have gastroesophageal reflux disease (GERD) – GERD occurs when food and acid in the stomach flow back into the esophagus causing heartburn and nausea after meals.
Patients usually experience symptoms when the hernia has increased in size, allowing stomach acids and undigested food to reflux into the esophagus. When this happens, patients experience GERD symptoms, such as:
Who to See and Types of Available Treatments
Since hiatal hernias do not cause unique symptoms, the condition is often discovered when diagnostic procedures that are meant to determine the cause of upper abdominal pain and heartburn are performed. These procedures include:
Blood tests - Performed to look for infection, anaemia, and injury to the heart, liver, and pancreas.
Esophagram - This test is performed to obtain a clear image of the oesophagus, stomach, and duodenum. It requires patients to drink barium that coats the upper digestive tract before undergoing an x-ray.
Endoscopy - Involves the use of an endoscope, a thin, flexible tube with a built-in camera on its end. The endoscope is passed down the patient’s throat allowing doctors to assess the condition of the oesophagus and the stomach.
Oesophageal manometry - A standard test for patients who are experiencing difficulty/pain when swallowing, chest pain, and heartburn. It involves the use of a small, flexible tube that is passed through the patient’s nose, down to the oesophagus, and then all the way to the stomach. With this test, doctors are able to measure and assess the function of the oesophagus and oesophageal sphincter.
Patients with asymptomatic hiatal hernias do not require any form of treatment. For those who are suffering from recurrent acid reflux and heartburn, certain medications can be prescribed. Surgical procedures are often only considered if the patient has a paraesophageal hernia, which increases the patient's risk of losing blood supply to the stomach.
Hiatal hernia surgery is now commonly performed using minimally invasive techniques that make use of a laparoscope. When compared to traditional open surgery, this method significantly shortens recovery time and minimises postoperative complications. It also allows patients to resume their normal activities after just five to seven days.
For the procedure, the surgeon makes 5-10 mm incisions in the abdomen where a laparoscope and other miniature surgical instruments are inserted. Guided by an imaging technology, the surgeon accesses the patient’s abdomen and makes necessary repairs. These involve pulling the protruding part of the stomach back into its proper place. In some cases, another procedure called fundoplication is also performed to wrap the top part of the stomach.
Hiatal hernia surgery is extremely effective in putting back the misplaced part of the stomach to its proper place, providing patients with immediate symptoms relief. However, the surgery does not provide any guarantee against recurrences. It also has risks of complications including abdominal bloating, difficulty swallowing, diarrhea, and abdominal stricture.
Townsend CM Jr, et al. Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice. 19th ed. Philadelphia, Pa.: Saunders Elsevier; 2012. https://www.clinicalkey.com.
Guidelines for the management of hiatal hernia. Society of American Gastrointestinal and Endoscopic Surgeons. http://www.sages.org/publications/guidelines/guidelines-for-the-management-of-hiatal-hernia/.