Overview
A hiatus hernia describes the herniation of abdominal organs (usually the stomach) through the oesophageal hiatus of the diaphragm into the thoracic cavity. Hernias with a larger defect may allow other organs to enter the thoracic cavity (e.g. the pancreas), however, this is rare.
The oesophageal hiatus is an opening in the diaphragm for the oesophagus, right and left vagus nerves, and oesophageal branches of the left gastric artery and vein.
Types
There are 4 types of hiatus hernia:
- Type I (sliding type) – 95% of cases:
- The gastro-oesophageal junction moves through the diaphragm
- Type II (rolling):
- This is a para-oesophageal hernia, where the gastro-oesophageal junction stays in place, but instead, a separate part of the stomach herniates through the diaphragm parallel to the oesophagus
- Type III: both para-oesophageal and sliding hernia
- Type IV: when the stomach as well as another organ herniate into the chest
Pathophysiology
A clear cause of hiatus hernia is not known. It is thought that muscle weakness and reduced flexibility with increasing age can stretch the oesophageal hiatus, increasing the likelihood of a hiatus hernia. This process may be accelerated by causes of increased intra-abdominal pressure including:
- Obesity
- Pregnancy
- Heavy lifting or straining
- Frequent or hard coughing (e.g. secondary to COPD) and/or sneezing
- Vomiting and/or straining during defecation
In type I (sliding) hiatus hernias, the displacement of the gastro-oesophageal function leads to a reduced pressure of the lower oesophageal sphincter, resulting in refluxing of stomach contents and symptoms similar to that of gastro-oesophageal reflux disease (GORD).
Epidemiology
- Incidence increases with age and it is often present in people >50 years old
- 95% are type I (sliding) hiatus hernias
Risk Factors
- Advanced age
- Causes of increased intra-abdominal pressure:
- Obesity
- Pregnancy
- Ascites
- Heavy lifting/straining
- Frequent or hard coughing (e.g. secondary to COPD)
- Vomiting
- Straining during defecation
- Previous gastro-oesophageal surgery
- Chest/abdominal trauma
- Skeletal abnormalities: scoliosis, kyphosis, and pectus excavatum
Presentation
Overview
Many features of hiatus hernia are similar to that of gastro-oesophageal reflux disease (GORD). In some, it could present as an exacerbation of their GORD and in some, they may be asymptomatic.
- Heartburn – retrosternal burning pain
- This is often worse when increasing intra-abdominal pressure (e.g. straining, bending forward, lying down etc.)
- Regurgitation – often worse when lying down
- Dysphagia or odynophagia:
- May be due to acid reflux causing oesophagitis, dysphagia is a red flag that always requires urgent assessment. See Dysphagia here
- Chest pain:
- May be due to oesophageal spasm. If severe, this can suggest hernia complications such as obstruction, ischaemia, or bleeding
- Bowel sounds may be heard in the chest
Other features
Other features may include:
- Respiratory signs and symptoms:
- Due to reduced lung expansion as the hiatus hernia takes up space in the thoracic cavity:
- Shortness of breath
- Reduced breath sounds
- Dullness to chest percussion
- Due to aspiration of refluxed material:
- Due to reduced lung expansion as the hiatus hernia takes up space in the thoracic cavity:
- Features of complications (e.g. strangulation, bowel obstruction, ischaemia, bleeding):
- Severe chest pain
- Severe vomiting
- Fever
- Confusion
Hiatus hernias are difficult to distinguish from other conditions such as GORD and oesophageal cancer clinically.
Investigations
Overview
Investigations are required to screen for malignancy as they can share features with hiatus hernia, and late diagnosis and management are associated with worse outcomes. Investigations include:
- Chest X-ray:
- May show a retrocardiac air bubble or may be normal
- Barium swallow:
- The standard test for diagnosing hiatus hernia, shows herniation of abdominal contents
Other tests include:
- Oesophagogastroduodenoscopy (OGD):
- Many patients undergo an OGD first due to the symptoms overlapping with conditions requiring one, such as oesophageal cancer
- May identify the hiatus hernia incidentally
Management
All patients
Most patients are managed with:
- Lifestyle changes – avoiding factors that can increase intra-abdominal pressure (e.g. weight loss, avoiding tight clothes, avoiding excess straining etc.)
- Proton pump inhibitors (PPIs) – for symptomatic control
Surgery
Most people with type 1 hiatus hernias do not require surgery. Surgery in the form of a laparoscopic fundoplication may be performed in the following scenarios:
- Type II (rolling, para-oesophageal) hernia:
- Even if asymptomatic due to the increased risk of complications such as strangulation which can be fatal
- Type 1 hernias if any of the following apply:
- Severe GORD
- Unable to/intolerant to medical therapy
- High doses of medication are required and/or do not work
- Respiratory complications
Patient Advice
Patients can be given advice regarding symptom reduction:
- Avoiding increased intra-abdominal pressure (e.g. losing weight, avoiding straining, avoiding tight clothes, avoiding large meals and eating more frequent and smaller meals instead)
- Elevating the head at night and avoiding eating too close before sleeping to reduce nocturnal symptoms
- Stopping smoking, reducing alcohol intake
Patients should also be given safety-netting advice:
- Seek urgent medical help if features of complications arise (e.g. severe chest pain, fever, persistent vomiting etc.)
Complications
- Complications due to refluxed stomach acid:
- Gastro-oesophageal reflux (GORD) due to refluxed stomach contents
- Oesophagitis due to acidic irritation of the oesophageal lining
- This can cause gastrointestinal bleeding
- Oesophageal stricture due to repeated oesophageal lining inflammation and scar tissue formation
- Barrett’s oesophagus and oesophageal cancer – due to persistent oesophageal inflammation
- Strangulation, ischaemia, and necrosis – a surgical emergency:
- More common in para-oesophageal hernia
- Associated with gastric volvulus which is potentially life-threatening
Prognosis
- Most people with type 1 hiatus hernias have adequate symptomatic relief with medical therapy
- Surgical correction may be associated with a reduction in symptoms in up to 90% of people