The esophageal hiatus is an elliptically shaped opening produced most often by parts of the right diaphragmatic crus, which encircles the distal section of the esophagus in a sling-like form.

Hiatal hernia in the Esophagus

A hiatal hernia is a medical ailment in which the top portion of the stomach or another internal organ bulges through a diaphragm hole. The diaphragm is a muscular tissue that aids in respiration and has a small hole, known as a hiatus, through which the esophagus travels before joining to the stomach. This is referred to as the gastroesophageal junction (GEJ).

The stomach pushes through the gap and into the chest in a hiatal hernia, compromising the lower esophageal sphincter (LES). The LES's laxity can allow stomach contents and acid to back up into the esophagus, which is the main cause of gastroesophageal reflux disease (GERD). While minor Hiatal hernias are generally asymptomatic and may be treated conservatively, big Hiatal hernias sometimes necessitate surgery.

Physiology

The pharyngoesophageal membrane, produced by the union of endothoracic and endoabdominal fascia, normally anchors the distal part of the esophagus to the esophageal hiatus.

The pharyngoesophageal ligament/membrane is inserted circumferentially into the esophageal muscles near the squamocolumnar junction (SCJ). By closing off possible gaps between the esophageal hiatus and the distal part of the esophagus, this ligament/membrane is crucial in preserving the competence of the GEJ and preventing migration of the GEJ and/or stomach into the posterior mediastinum.

The esophagus body shortens during normal swallows owing to contraction of the esophageal longitudinal muscles, and the pharyngoesophageal ligament/membrane is stretched. As a result, the GEJ and a portion of the stomach are proximally shifted via the esophageal hiatus.

The elastic rebound of the pharyngoesophageal ligament/membrane returns the migrating segment to its usual place at the end of each swallow. The pharyngoesophageal ligament/membrane, on the other hand, gets more slack with aging by reducing the number of elastic tissues, presumably due to wear and tear from recurrent stress of swallowing, predisposing to the development of hiatal hernia.

Excessive contraction of the esophagus longitudinal muscle, higher abdominal pressure as seen in power athletes, pregnancy, hereditary susceptibility, and prior surgery can all induce pharyngoesophageal ligament/membrane flexibility loss.

Some argue that, rather than hiatal hernia, reflux esophagitis is the major culprit that begins and sustains the esophagitis-hernia complex; one opossum research found that acidification of the esophageal mucosa caused longitudinal muscle contraction, resulting in esophageal shortening.

Types of Hiatal Hernia

Hiatal hernias are divided into 4 types:

• Type I (slide type), which accounts for more than 95 percent of Hiatal hernias, arises when the GEJ is pushed upwards towards the hiatus.
• Type II is a paraesophageal hiatal hernia, which arises when a portion of the stomach migrates into the mediastinum parallel to the esophagus.
• Type III is a paraesophageal hernia and a sliding hernia in which the GEJ and a part of the stomach have migrated into the mediastinum.
• Type IV herniation occurs when the stomach, as well as another organ such as the colon, small intestine, or spleen, herniates into the chest.

Types II–IV are known as paraesophageal hernias (PEH), and their major clinical significance stems from the possibility of ischemia, blockage, or volvulus. The anatomic categorization of a hiatal hernia is crucial, particularly for the therapeutic strategy, because the criteria for the surgical technique varies significantly between sliding and paraesophageal hernias.

Etiology

Hiatal hernias can occur at birth or develop later in life. There is a higher frequency among the elderly. Muscle weakening, as well as loss of flexibility and elasticity with age, is thought to lead to the formation of a hiatal hernia. During swallowing, the top portion of the stomach may not return to its normal place beneath the diaphragm as a result of this.

Other risk factors, such as high intraabdominal pressure, have been discovered. Obesity, pregnancy, chronic constipation, and chronic obstructive pulmonary disease are common causes (COPD). Trauma, age, past operations, and genetics can all contribute to the formation of a hiatal hernia.

Epidemiology

• Hiatal hernias become more common as people become older. A hiatal hernia affects around 55% to 60% of those over the age of 50. However, only around 9% of people have symptoms, and this varies depending on the kind and competence of the lower esophageal sphincter. The great majority of these hernias are sliding Hiatal hernias of type I.
• Only approximately 5% of Hiatal hernias are type II paraesophageal hernias, in which the LES stays stationary but the stomach protrudes over the diaphragm. Women have a higher prevalence, which might be due to increased intraabdominal pressure during pregnancy.
• Hiatal hernias are more frequent in Western Europe and North America, while they are uncommon in rural Africa.

Hiatal hernia and GERD 

The link between Hiatal hernias and gastroesophageal reflux disease (GERD) has been hotly disputed in recent decades, with the relevance of Hiatal hernias being overstated at first and subsequently almost ignored.

The widely recognized "two-sphincter theory" states that both the morphological (hiatal hernia) and physiological (lower esophageal sphincter) characteristics of the gastroesophageal junction play essential but separate roles in the etiology of GERD. The gastroesophageal junction is a complicated anatomical region with an intrinsic antireflux barrier function. 

However, in individuals with hiatal hernia, the gastroesophageal junction becomes incompetent and esophageal acid clearance is impaired, facilitating the development of GERD. Type I (slide) Hiatal hernias are the most closely related to GERD among the four forms of Hiatal hernias (I, II, III, and IV). Because GERD can induce reflux esophagitis, Barrett's esophagus, and esophageal cancer, a better knowledge of this relationship is required.

Hiatal hernias can be identified radiographically, endoscopically, or manometrically, each with its own set of limitations, particularly in the identification of Hiatal hernias less than 2 cm in length. High-resolution manometry should be a promising tool for correctly evaluating the relationship between Hiatal hernias and GERD in the future.

The management of a hiatal hernia is similar to that of GERD and should be reserved for people who exhibit symptoms associated with this illness. Patients with refractory symptoms, as well as those who develop problems such as recurrent bleeding, ulcerations, or strictures, should be evaluated for surgery.

Hiatal hernia symptoms

The most common reason for a hiatal hernia examination is gastroesophageal reflux illness (GERD). Patients frequently complain of heartburn and, in some cases, regurgitation. While heartburn is the most prevalent complaint, some patients will also complain of extra-esophageal symptoms such as a persistent cough or asthma. 

The diagnosis of gastroesophageal reflux disease (GERD) appears to be connected to the occurrence of symptomatic instances of hiatal hernia, with the two diseases being closely associated. The most frequent symptom of hiatal hernia is gastroesophageal reflux, which manifests as regurgitation and heartburn, while less common symptoms include dysphagia, epigastric or chest discomfort, and even chronic iron deficiency anemia. Large hernias can cause dysphagia, early satiety, and regurgitation.

The presence of regurgitation or extra-esophageal symptoms is usually an indication of disease progression. However, not all individuals with regurgitation have GERD, and it is critical to determine if the regurgitated food is digested or undigested.

Undigested food might be indicative of another disease, such as achalasia or a diverticulum. Dysphagia is another symptom of severe illness. This is usually the result of a mechanical impediment. When this happens, it might be a sign of another illness, such as a peptic stricture, tumor, diverticula, or primary motor dysfunction.

In individuals with a hiatal hernia and GERD, physical examination seldom helps establish the diagnosis. The presence of aberrant supraclavicular lymph nodes in individuals with heartburn and dysphasia may indicate esophageal or stomach cancer and is an essential element of the assessment.

Hiatal hernia how to diagnose

Hiatal hernia diagnosis can be difficult at times owing to changes in the architecture of the esophagogastric junction during deglutition, breathing, and movement. A thorough history and physical examination are required, since they may disclose symptoms that were previously undetected.

The size of the herniated stomach and the position of the gastroesophageal junction can be determined using barium swallow radiography. The majority of research concur that barium swallowing is still necessary for the diagnosis of hiatal hernia. Hiatal hernias can be identified using this approach if the axial herniation is more than 2 cm.

A video-esophagram is also recommended since it allows you to examine bolus transit. Through barium swallow radiography, GERD-related esophageal motility dysfunction, stenosis, and stricture can be seen.

The technique can also aid in the diagnosis of a short esophageal sphincter. The biggest disadvantage is that you will be exposed to radiation. In a patient who is being considered for surgical therapy, the preoperative work-up will assist confirm the diagnosis, rule out alternative pathologic entities, and lead the operative intervention.

• Endoscopy: 

This is a critical step in the assessment of individuals with GERD and a suspected hiatal hernia who are candidates for surgery. This examination can rule out other illnesses, such as tumors, while also demonstrating the existence of esophageal damage.

• Manometry: 

Esophageal manometry gives useful information on esophageal motility. A 2 cm or greater separation between the crural diaphragm and lower esophageal sphincter is considered diagnostic for hiatal hernia. 

Esophageal manometry should be done before any operation, especially if achalasia or other motility problems are suspected. Before conducting fundoplication surgery, it is also necessary to confirm the integrity of the esophageal peristalsis, which can be accomplished with high-resolution manometry (HRM), which enables real-time pressure monitoring.

• pH monitoring: 

The 24-hour pH test is the gold standard for acid reflux diagnosis. A probe is positioned 5cm above the GE junction and the quantity of acid to which it is exposed is measured in this test.

• Esophagography:

The esophagogram is useful for learning about the anatomy of the esophagus and proximal stomach. During this examination, anatomic anomalies such as tumors or strictures may be found.

• Computer tomography (CT)

Although CT is not usually suggested, it can provide additional information about the location and kind of hiatal hernia. It is usually discovered by chance when doing a CT scan for another reason.

Hiatal hernia treatment

Hiatal hernia (HH) is fairly common in the general population and is characterized by a variety of non-specific symptoms, the majority of which are connected to gastroesophageal reflux syndrome. Depending on the presence of problems, treatment might be difficult at times.

The treatment of Hiatal hernias is determined by the kind of hernia and the severity of the symptoms. By treating stomach acid secretion, the goal is to minimize the symptoms of gastroesophageal reflux disease (GERD). Lifestyle changes are the first line of defense and include the following: Weight reduction, raising the head of the bed by 8 inches while sleeping, avoiding meals 2–3 hours before night, and avoiding "trigger" foods including chocolate, alcohol, caffeine, spicy foods, citrus, and carbonated drinks.

The following step is a double dosage of a proton pump inhibitor (PPI). This may be both therapeutic and diagnostic, as persistent symptoms frequently necessitate a more thorough assessment. The indication for surgical treatment has shifted since the introduction of PPIs.

The current guideline is to use the smallest amount of PPI necessary to manage symptoms. Antacids and histamine 2 receptor antagonists are two more options. Patients with mild symptoms can use these medications on demand, while those with chronic problems despite PPI therapy should use them as a supplement.

Hiatal hernia surgery

Patients with significant esophageal damage, such as ulcers, strictures, or Barrett's mucosa, should be evaluated for surgery. Other individuals, such as those who have had symptoms for a long time or who have had symptoms that have not resolved while on medicinal therapy, should also be evaluated for surgical surgery.

The cost of surgery has dropped due to improvements in less invasive methods for the treatment of GERD. Surgical therapy may be regarded the treatment of choice for patients with a life expectancy of greater than 8 years who require lifetime care due to a mechanically faulty LES.

Due to the flexibility of the stomach's peritoneal attachments and consequent rotation of the gastric fundus, paraesophageal hernias might appear with a gastric volvulus. This is classified as a surgical emergency.

Current guidelines advocate operational treatment of all symptomatic paraesophageal hernias as well as entirely asymptomatic big hernias in patients under the age of 60 who are otherwise healthy.

Nissen fundoplication (360-degree wrap)

• Nissen fundoplication (360-degree wrap): 

This entails fully encircling the GEJ with the stomach fundus. This is often done with a 52 French bougie in place to guarantee proper approximation without overstretching the wrap. To mobilize the fundus, the short gastric arteries are dissected from the larger curvature of the stomach. The pharyngoesophageal membrane is thoroughly dissected over the left crus, and the crural fibers are detected.

Unless there is preexisting esophageal dysmotility, a Nissen fundoplication (360°) is usually performed following most hiatal hernia surgeries, in which case a Toupet fundoplication (270°) is preferable. Recent research suggests that a full fundoplication may be more helpful due to a lower anomaly in the pH profile and a stronger effect.

Laparoscopic surgery offers the benefits of a less invasive technique, such as shorter hospital stays, faster recovery times, less postoperative discomfort, and fewer pulmonary problems. Of course, there are certain drawbacks to laparoscopic surgery, such as two-dimensional imaging, limited mobility of laparoscopic equipment, and poor ergonomics for surgeons.

• Partial fundoplication:

When esophageal motility is low, a partial fundoplication is usually the best option. The Dor technique, which is an anterior wrap, and the Toupet operation, which is a posterior wrap, are the two most frequent partial fundoplications.

These two treatments, as opposed to the entire 360-degree wrap performed with a Nissen, require generating a 180 to 250-degree wrap. When motility is a challenge, it is considered that a partial wrap will assist prevent blockage in the esophagus.

• Dor procedure:

This is accomplished by folding the fundus over the anterior portion of the esophagus and then attaching it to the hiatus and esophagus in the same way as the 360-degree wrap is. This wrap has been utilized in the treatment of GERD, but it is more often used to treat individuals with achalasia who have had an anterior myotomy.

• Toupet procedure:

The complete esophageal dissection for this surgery is the same as for a Nissen, with the esophagus mobilized. This surgery, as opposed to the Nissen, forms a 220 to 250-degree wrap around the posterior portion of the esophagus and is the procedure of choice if motility is a concern.

Differential Diagnosis

The differential diagnosis of a patient with GERD can be extremely wide, which is why such a comprehensive work-up is performed prior to surgical treatment. Heartburn is commonly characterized as an epigastric caustic or burning feeling. This does not usually spread to the back or be reported as a pressing sensation. This is an essential component of the history and physical because it helps differentiate GERD from other diseases like pancreatitis or acute coronary syndrome.

GERD extra-esophageal symptoms show as laryngeal or pulmonary symptoms and come from the respiratory tract. It might be difficult to determine the cause of such symptoms, so keep an eye out for primary esophageal motility problems, stomach or esophageal malignancy, and main lung illness.

If a patient arrives with such symptoms and the main work-up is negative, it is critical to look into other possible causes. Consultation with a pulmonologist is frequently required.

Prognosis

Hiatal hernia surgery success can be assessed by symptom alleviation, improvement in esophageal acid exposure, complications, and the necessity for reoperation. Over the course of ten years, one prospective research tracked 100 individuals who had antireflux surgery. After ten years, they discovered a 90% reduction in symptoms.

Over the last two decades, collective operation management experience has proven to enhance outcomes. Symptom improvement has improved with experience, whereas perioperative complications have reduced.

Complications of surgery

Complications following surgery are usually minimal and unrelated to the procedure itself. The total 30-day mortality rate linked with antireflux surgery is predicted to be 0.19 percent. Complications associated with antireflux surgery include the following:

• Pneumothorax: This is the most often seen intraoperative complication. However, it has been observed that this occurs in less than 2% of patients.
• Gastric and esophageal injuries: occur in approximately 1% of patients undergoing Nissen fundoplication. 
• Splenic and liver injuries: This can result in bleeding and affects approximately 2.3 percent of patients. Major injury is uncommon.
• Dysphagia: This is most often caused by surgical edema and usually resolves without additional intervention.

Conclusion 

Esophageal hiatal hernias have been found to affect between 10% and 50% of the population. Hiatal hernias are defined by a protrusion of the stomach into the thoracic cavity caused by a widening of the diaphragm's right crus. Esophageal Hiatal hernias are classified into four kinds: sliding (type I), paraesophageal (type II), mixed (type III), which combines parts of types I and II, and gigantic paraesophageal (type IV) (type IV).

Each kind may have distinct symptoms and consequences. The potential severity of the symptoms demands an accurate and timely diagnosis. The use of barium swallow on chest radiographs aids in the diagnosis. Laparoscopic fundoplication is used to treat sliding hernias. The purpose of this study is to examine the substantial literature on hiatal hernias in order to improve awareness and diagnosis of this condition.

Managing hiatal hernias and reflux necessitates the collaboration of many professionals. Primary care physicians, radiologists, gastroenterologists, and surgeons should all be part of the team. Both diagnosis and surgical planning need diagnostic tests. This necessitates endoscopy, pH monitoring, and esophagography, all of which need a collaborative effort from various teams. This leads to more accurate diagnosis, better surgical outcomes, and higher patient satisfaction.