Gastroparesis is a chronic debilitating disease that presents with symptoms of nausea, vomiting, bloating, early fullness after eating and upper abdominal pain. Along with these symptoms, an objective finding of delayed stomach emptying on specialized imaging and absence of mechanical obstruction on endoscopy are both required for a formal diagnosis. The mechanism of cellular and molecular breakdown that leads to gastroparesis has been elusive and complex, with multiple variables involved. At its core, the crux of this problem is the impaired coordination between stomach muscles, nerves, and pacemaker cells. A significant decrease in the number of stomach pacemaker cells is another purported mechanism behind this condition.
Classifying & Managing Gastroparesis
The majority of gastroparesis cases can be classified into three main groups: idiopathic, diabetic, and postsurgical. Idiopathic gastroparesis means that patients meet clinical and objective evidence of poor gastric emptying without a primary identified cause. One important proposed cause of idiopathic gastroparesis is post-viral; some people can develop rapid onset of gastroparesis symptoms after a viral (usually upper respiratory) disease.
Optimizing oral nutrition and improving the quality of life is the main goal of treatment of gastroparesis. Initially, management of this condition was limited to changes in one’s diet and lifestyle, and liberal use of motility and anti-nausea medications. The majority of patients would experience some relief of their symptoms with this management, but those improvements were usually short-lived and not significant. However, over the last two decades, a number of new technologies and procedures have been attempted, validated, and approved for treatment of this challenging disease.
When patients are not achieving good results with, or are intolerant of, current dietary and medical treatments, they should be referred to surgeons who specialize in minimally invasive surgical approaches to gastroparesis. Depending on the severity of symptoms, these patients may be candidates for gastric electrical stimulation therapy, pyloric surgery, sleeve gastrectomy or Roux-en-Y gastrojejunostomy with or without removal of a part of the stomach. A combination of two surgical modalities may also be offered to some patients:
- Gastric electrical stimulators have been approved for use by the Food and Drug Administration for drug-refractory gastroparesis since early 2000s. This device consists of electrodes that are surgically placed into the stomach by using “key-hole” surgery (laparoscopy), which are then connected to a small battery. The battery is placed inside the soft tissues of patient’s abdominal wall and can function up to 10 years before needing to be replaced. Once placed appropriately, the gastric pacemaker uses mild electrical pulses to gently stimulate the stomach. This therapy has been shown to reduce the symptoms of nausea and the number of vomiting episodes that a patient with gastroparesis experiences on a daily basis.
- Additional minimally invasive surgical procedures include pyloric surgery – division of the pyloric sphincter muscle at the bottom of the stomach, vertical sleeve gastrectomy – removal of greater than 50% of poorly functioning stomach tissue, and Roux-en-Y gastrojejunostomy with or without partial gastrectomy – partitioning of the stomach into two compartments, with a direct attachment to the small bowel from the patient’s upper stomach. Each of these techniques has been shown to normalize gastric emptying by either reducing the delay experienced by food trying to leave the stomach or by increasing its transit time through the stomach. These anatomical alterations lead to a significant reduction of abdominal pain, early satiety, and bloating in a majority of patients. Only the most qualified and very experienced minimally invasive surgeons specializing in management of gastroparesis will be able to provide the full spectrum of surgical approaches to individual patients.
References:
- Camilleri M., et al. “Gastroparesis.” Nature Reviews: Disease Primers. (2018) 4:41.
- Liu N. and Abell, T. “Gastroparesis Updates on Pathogenesis and Management.” Gut and Liver. (2017) 11:5.