What is a hiatal hernia?
A hiatal hernia, also known as a hiatus hernia, is the abnormal protrusion of the upper part of the stomach into the thoracic cavity through a defect in the diaphragm. The incidence of a hiatal hernia increases with age and it is fairly prevalent in the over 50 age group. Many hiatal hernia cases are silent (asymptomatic).
Types of hiatal hernia
There are broadly two types of hiatal hernias, a sliding or rolling hiatal hernia, but is possible to have a mixed type which is a combination of a sliding and rolling hiatal hernia. :
- Type I or sliding hiatal hernia
- Type II or rolling hiatal hernia or paraesophageal hiatal hernia
- Type III or “mixed hiatal hernia“
Sliding hiatal hernia
A sliding hiatal hernia (type I) is the most common type, accounting for about 95% of cases. In a sliding hiatal hernia, the gastroesophageal junction is not maintained in the abdominal cavity but is allowed to move back and forth (slide) between the thoracic and abdominal cavity. This, along with the negative pressure in the thoracic cavity can result in weakening of lower esophageal sphincter (LES). This allows for the back flow of the stomach contents into the esophagus (acid reflux). The risk of reflux increases with the size of the hernia.
Rolling hiatal hernia
A olling hiatal hernia (type II) is a type of paraesophageal hernia and accounts for 4% to 5% of hiatal hernias. The defects in type II hiatal hernias are usually large. The gastroesophageal junction remains fixed at the normal position in the abdomen, but hiatal defect allows protrusion of abdominal viscera into thorax.
A part of the stomach (usually the fundus) herniates through the defect and remains by the side of esophagus. The thorax has a negative pressure compared to the abdominal cavity, and this facilitates the abdominal visceral herniation (protrusion) into thorax. Rarely part of the colon or the spleen may pass through the hiatal defect.
Mixed hiatal hernia
A type III hiatal hernia is a paraesophageal hernia having combined features of sliding and rolling hiatal hernia. In the type III hiatal hernia the gastroesophageal junction can slide into the thorax and the fundus of the stomach (or colon) is free to roll into the thorax.
Symptoms of a Hiatal Hernia
Many hiatal hernia cases are asymptomatic meaning that a person does not experience any symptoms. Typical symptoms of a hiatal hernia includes heartburn, regurgitation, abdominal and chest pain and chronic nausea.
However, most patients with a sliding hiatal hernia (type I) and paraesophageal/rolling hernia (type II) have associated gastroesopageal reflux disease (GERD). Small hernias, especially small sliding hernias, are less frequently associated with reflux but the risk of GERD increases with size of the hernia. GERD usually presents with chronic heartburn but other symptoms like nausea and excessive belching may also be present.
Symptoms usually start with heartburn and slowly progress to regurgitation of digested food. The onset of regurgitation indicates an enlarging hiatal hernia. With progression of the hernia, the regurgitation becomes severe, even reaching stages where a person may be unable to bend without experiencing regurgitation.
Discoloration of the teeth (yellowing teeth) may be seen in patients with severe long standing GERD with regurgitation of gastric contents into their mouth. Some patients with large paraesophageal hernias can also develop respiratory symptoms like cough, wheezing and is often associated with laryngopharyngeal reflux (LPR Reflux).
The herniated organs can result in abdominal or chest pain (epigastric and retrosternal) due to torsion or distension. The lining of the stomach (gastric mucosa) can sustain ischemic injury in following such events and may result in bleeding. Prolonged or severe upper gastrointestinal bleeding can lead to anemia.
The paraesophageal hernias are more commonly associated with difficulty in swallowing (dysphagia). This is more pronounced with solid foods than with liquids. Dysphagia is often due to mechanical obstruction of the food passage, which can be due to recurrent or acutely developing gastric or esophageal obstruction.
Diagnosis of a Hiatal Hernia
- A history of GERD, especially with severe regurgitation, should raise the suspicion of a hiatal hernia.
- Often a hiatal hernia is diagnosed during routine investigation of upper gastrointestinal complaints like a radiological contrast study of the esophagus.
- An upper GI endoscopy is performed to assess the mucosal injury and evaluate any blood loss.
- Manometry is done for assessing the effectiveness of peristalsis and the lower esophageal sphincter (LES) pressure.
- Gastric pH monitoring is an optional test and helps in quantifying the reflux.
Complications of Hiatal Hernia
- Esophageal stricture is an abnormal narrowing of the esophagus and may arise from chronic reflux. Repair of shortened esophagus requires lengthening with procedures like double-staple technique.
- Barrett’s esophagus is a precancerous condition where the chronic exposure to gastric reflux changes the epithelial lining of esophagus (from squamous to columnar epithelium).
- Adhesions of the abdominal organs may develop between the hernial sac in a long standing paraesophageal hernia. This can lead to incarceration, bowel obstruction or strangulation.
- Gastrointestinal bleeding can result from injury to the mucosal lining and in chronic cases it can lead to anemia.
- Respiratory complications as discussed under laryngopharyngeal reflux may arise with chronic reflux. Large hernias can impair lung expansion leading to further respiratory problems.
Hiatal Hernia Treatment
Asymptomatic patients do not require any treatment for a hiatal hernia. The approach to treatment may depend on the severity of hiatal hernia symptoms and complications.
Diet and Lifestyle
Cases with only mild GERD symptoms may be managed with dietary and lifestyle measures as outlined in the Acid Reflux Diet. The main point include :
- Avoid lying down or sleeping immediately after a meal.
- Smaller frequent meals should replace large meals.
- Stop cigarette smoking.
- Avoid using tight clothing that constricts the abdomen
- Elevate the head end of the bed.
In moderately symptomatic GERD patients, drug therapy is recommended along with diet and lifestyle changes as mentioned above. The drug therapy targets suppression of the gastric acid secretion which reduces the injury to esophageal lining. This includes the use of :
Prokinetic drugs increase gastrointestinal motility and facilitate quicker emptying of the stomach. Patients with persisting symptoms after a 6-week acid suppression therapy require further evaluation. The medical management of symptoms of hiatal hernia patients with proton pump inhibitors and motility agents has dramatically reduced the number of patients requiring for surgical treatment.
Surgery is recommended in severely symptomatic hernia patients, patients with serious esophageal injuries like an esophageal stricture and bleeding ulcers, and patients with Barrett’s esophagus. Patients not responding to medical therapy or with frequent relapses while on medication may also be considered for surgical management as an option.
Various surgical techniques are used to correct the hiatal hernia.
- Nissen fundoplication (360-degree wrap) is the surgical procedure of choice for most patients. The fundus of the stomach is wrapped around the lower end of the esophagus by laparoscopic surgery (preferred) or open surgery. This prevents the gastric acid reflux and the protrusion of the stomach through defect in the diaphragm. A partial fundoplication may be performed when the esophageal motility is not satisfactory. The newly evolved endoscopy based approaches have not been effective in management of hiatal hernia
- Laparoscopic paraesophageal hernia repair is reasonably safe and associated with fewer complications and recurrences than open abdominal approaches. Use of a synthetic mesh is limited by the occasional esophageal erosions, ulceration and strictures associated with its use. However the newly introduced absorbable biological mesh may be used in certain large hiatal hernias.
Complications of Hiatal Hernia Surgery
Related complications of a hiatal hernia surgery include pneumothorax, injury to liver, spleen or hollow visceral organs, paralytic ileus, difficulty in swallowing, retention of urine and incision wound infection. There is a 5% chance for failure of the surgery and persistence of the symptoms.