A hiatal hernia occurs when a portion of the stomach pushes upward through the diaphragm, a muscular wall separating the chest and abdomen, into the chest cavity. Gastric sleeve surgery, also known as sleeve gastrectomy, removes a large portion of the stomach to create a smaller, tube-shaped stomach. While effective for weight loss, this surgery can sometimes lead to a hiatal hernia, even if one was not present before. This article explores factors contributing to hiatal hernia formation after gastric sleeve surgery.
Understanding Gastric Sleeve Surgery and Relevant Anatomy
Gastric sleeve surgery significantly reduces the stomach’s size by removing approximately 75-80%, creating a narrow, tube-shaped “sleeve” that connects the esophagus to the small intestine. This procedure restricts food intake and promotes weight loss by altering hormonal signals. The remaining stomach, or sleeve, maintains its connection to the esophagus at the gastroesophageal junction.
The diaphragm is a large, dome-shaped muscle that separates the chest and abdominal cavities. It has a natural opening, the esophageal hiatus, through which the esophagus passes to connect with the stomach. In a healthy individual, the diaphragm and the phrenoesophageal ligament help keep the stomach securely in the abdominal cavity. After gastric sleeve surgery, the altered anatomy of the stomach interacts differently with this diaphragmatic opening.
Surgical Factors and Their Role in Hernia Formation
The technical aspects of gastric sleeve surgery can directly influence hiatal hernia development. Excessive tension on the newly formed stomach tube during sleeve creation may pull the stomach upward towards the chest cavity. This tension can occur if the sleeve is created too tightly or if there is insufficient mobilization of the stomach from surrounding tissues. Such mechanical stress on the gastroesophageal junction and the diaphragmatic hiatus can contribute to its widening.
The extent of dissection around the esophagus and hiatus during the procedure also plays a role. If dissection is too extensive, it can weaken natural supporting structures around the esophageal hiatus, such as the phrenoesophageal ligament. This weakening compromises the barrier that normally prevents stomach migration. Furthermore, if a pre-existing hiatal defect was present but not recognized or adequately repaired, the new anatomical configuration can exacerbate this weakness.
The size and shape of the remaining gastric sleeve can also influence hernia formation. A wider sleeve might exert less upward pressure on the hiatus, while a very narrow sleeve could increase intra-gastric pressure, pushing against the diaphragmatic opening. Proper surgical technique aims to balance effective restriction with minimizing undue tension or pressure on surrounding anatomical structures.
Post-Operative Physiological Changes as Contributing Factors
Significant physiological changes occur after gastric sleeve surgery that can contribute to hiatal hernia development. Rapid and substantial weight loss, a hallmark of this procedure, leads to a reduction in intra-abdominal fat and overall abdominal volume. The loss of this fat pad, which normally provides support, can alter pressure dynamics around the diaphragm. This reduction in supportive tissue may allow for increased upward migration of the stomach through the hiatus.
Changes in stomach emptying and gastric pressure within the newly formed sleeve can also exert stress on the diaphragmatic opening. The tubular shape of the stomach can lead to altered pressure gradients, potentially increasing pressure within the sleeve. This elevated pressure, particularly during digestion or with certain movements, can continuously push against the esophageal hiatus, gradually widening it over time. The altered angle of the gastroesophageal junction, due to the sleeve’s new configuration, may also reduce its natural anti-reflux barrier and make it more susceptible to upward displacement.
Patient-Specific Risk Factors
Individual patient characteristics and pre-existing conditions can increase susceptibility to hiatal hernia after gastric sleeve surgery. A pre-existing hiatal hernia, even if small and asymptomatic before surgery, represents a weakness in the diaphragm that can be exacerbated by surgical changes. Surgeons often evaluate for and repair these during sleeve gastrectomy; however, if undetected or inadequately addressed, they pose a significant risk.
Inherent weakness of connective tissues, which can be genetically predisposed, also contributes to the risk. Individuals with weaker connective tissues may have a less robust phrenoesophageal ligament, making them more prone to diaphragmatic opening widening. Conditions that chronically increase intra-abdominal pressure also elevate the risk. Chronic coughing, often seen in smokers or those with respiratory conditions, repeatedly pushes abdominal contents upwards against the diaphragm. Severe constipation, involving frequent straining, can similarly increase intra-abdominal pressure and contribute to hernia development.