Gastric Outlet Obstruction
Gastric outlet obstruction (GOO) is a mechanical obstruction involving the distal stomach or proximal duodenum resulting in delayed gastric emptying. It is not a single entity but rather can be the result of a variety of causes.
- Pyloric obstruction
- Stenosis of the pylorus
Epidemiology & Demographics
Accurate statistics on incidence are not available. It is postulated that GOO has decreased over the past several decades due to improved treatment options for peptic ulcer disease, which is historically the leading cause for GOO. More recent data suggest that up to 50% to 80% of new cases are cancer related.
- •History of pancreatic or gastric malignancy
- •Untreated peptic ulcer disease
- •Chronic NSAID use
- •Helicobacter pylori infection
Physical Findings & Clinical Presentation
- •Signs of dehydration (tachycardia, hypotension, dry mucous membranes) are often present.
- •Malnutrition may be evident depending on the chronicity of the obstruction.
- •Epigastric tenderness may be present.
- •Abdominal distention/tympanic mass in epigastric area or left upper quadrant (LUQ).
- •Succession splash may be heard with a stethoscope placed on the abdomen while the patient rocks side to side. It has a low sensitivity and is positive if present 3 hours after a meal, which suggests retained gastric contents.
- •Sister Mary Joseph nodule (a periumbilical node) or Virchow’s node (a left supraclavicular node) may be palpated in the setting of metastatic gastric cancer.
Patients with GOO often present with postprandial nonbilious vomiting, epigastric pain, nausea, easy satiety, and weight loss, though the presentation may differ depending on the cause of the obstruction. Patients with malignancy as the underlying cause often present with a more acute onset of symptoms, whereas those with peptic ulcer disease have more chronic symptoms. Physical examination findings most commonly include signs of dehydration and malnutrition, as well as abdominal tympanic distention and epigastric tenderness.
What causes of Gastric Outlet Obstruction?
- •Historically, the most common cause of GOO was peptic ulcer disease; however, with the availability of proton pump inhibitors and treatment to eradicate H. pylori infection, this has been drastically reduced. Malignancy now accounts for the majority of cases, most frequently pancreatic adenocarcinoma with spread to the duodenum or stomach, or gastric cancer. Other rarer malignant causes include advanced gallbladder carcinoma or cholangiocarcinoma, gastric lymphoma, malignancy of the duodenum, ampullary cancer, and gastric carcinoid.
- •Benign causes include peptic ulcer disease, caustic ingestion, stricture and scarring from NSAIDs or postsurgery, acute or chronic pancreatitis, and pancreatic pseudocysts. Rare causes include gastric obstructing polyps, bezoars or volvulus, Bouveret syndrome (gallstone in the proximal duodenum), congenital annular pancreas, or infiltrative disease from Crohn, amyloid, or tuberculosis.
Causes of Gastric Outlet Obstruction
|Peptic ulcer disease||Pancreatic cancer|
|Gastric polyps||Gastric cancer|
|Caustic ingestion||Gallbladder carcinoma|
|Stricture/scarring from NSAIDs, radiation, postsurgical||Cholangiocarcinoma|
|Acute or chronic pancreatitis||Ampullary cancer|
|Pancreatic pseudocyst||Duodenum cancer|
|Bouveret syndrome (gallstone in the proximal duodenum)||Gastric carcinoid|
|Congenital annular pancreas|
|Infiltrative disease (Crohn, amyloid, tuberculosis)|
NSAID, Nonsteroidal antiinflammatory drug.
Diagnosis is based on clinical presentation, imaging, and often endoscopy with biopsy.
It is important to exclude motility causes such as gastroparesis from diabetes, medications, or viral infections. The primary differential diagnosis to be considered in GOO is in determining the causes of the obstruction. See Table 1.
During the initial work up of GOO, it is important assess hydration and nutrition status and to determine the underlying cause. Consider the following:
- •Complete blood count, electrolytes, abdominal CT scan, and upper endoscopy
Laboratory tests are not diagnostic but should include a complete blood count and electrolytes.
- •Electrolytes may reveal evidence of contraction alkalosis and hypokalemia, especially in the setting of repeated vomiting.
- •The complete blood count may show evidence of anemia in a patient with underlying malignancy that may become more apparent after fluid replacement.
- •Abdominal x-rays are often not diagnostic but may reveal a significant gastric bubble.
- •CT scan of abdomen may reveal gastric distention, mass, and evidence of malignant spread. This should be ordered without oral contrast if upper endoscopy is anticipated.
- •Upper endoscopy is usually needed for both diagnostic and therapeutic purposes. This should occur after nasogastric tube placement and suction to remove gastric contents to reduce the chance of aspiration during the procedure. Endoscopy can determine the location and extension of the obstruction and may offer a diagnosis through biopsy.
How is Gastric Outlet Obstruction treated?
The general management of gastric outlet obstruction consists of hydration, correcting metabolic abnormalities, pain management, and alleviating the obstruction.
- •Nothing by mouth (NPO) and nasogastric tube for gastric decompression
- •Intravenous fluids using isotonic saline with potassium replacement
- •Nutritional support
- •Management of the obstruction depends on the underlying cause. The following recommendations are for GOO from peptic ulcer disease, the most common benign cause of GOO. Patients with rarer, benign causes of GOO may benefit from some of the following interventions as well but treatment will be more specifically tailored to the underlying cause and decided with consultations from gastroenterology and surgery.
- •GOO can be initially managed with 48 to 72 hours of gastric decompression, fluid replacement, correction of metabolic abnormalities, and acid suppression. H. pylori infection should be treated if appropriate. If this approach is unsuccessful endoscopic dilation or surgery should be considered.
Endoscopic Balloon Dilation
Endoscopic balloon dilation (EBD) is most commonly indicated in patients with GOO from peptic ulcer disease. It results in a lasting response in 70% to 80% of patients; however, narrow strictures often need gradual dilations performed in a stepwise fashion over several sessions. Recurrent stenosis requiring two or more dilations is an indication for surgery.
Is surgery mandatory for Gastric Outlet Obstruction?
- •The goals of surgery include alleviating the obstruction and suppressing acid secretion.
- •Surgical inventions such as laparoscopic antrectomy or distal gastrectomy with vagotomy, vagotomy with drainage via pyloroplasty, and laparoscopic gastrojejunostomy are potential options.
Endoscopic Ultrasound-GuideD Gastroenterostomy
Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) is emerging as an potential treatment option for benign (and malignant) GOO and might be associated with fewer adverse effects, fewer recurring symptoms, and decreased need for subsequent interventions compared with other techniques. However, further research is necessary to determine optimal technique and to directly compare the efficacy of EUS-GE with other endoscopic procedures and surgical options.
Management of malignant GOO depends on the type and extent of the underlying malignancy. General therapeutic options include endoscopic stenting, surgical resection or bypass, gastrostomy with possible feeding tube placement, and EUS-GE. Surgery is the treatment of choice when resection can be potentially curative. Consultation with gastroenterology, surgery, oncology, and palliative care can guide treatment decisions.
Acute General Treatment
- •Proton pump inhibitors to decrease gastric secretions
- •Antiemetics to treat nausea
- •Pain management
- •Eradication of H. pylori infection, if applicable
- •Avoidance of nonsteroidal antiinflammatory medications
- •Proton pump inhibitors
Prognosis depends on the underlying cause of the GOO.
Gastroenterology should be consulted for initial diagnostic and therapeutic options with consultations from surgery, oncology, and palliative care as needed.
Pearls & Considerations
- •Malignancy should be considered as the primary cause until proven otherwise.
- •All patients, regardless of cause, benefit from a proton pump inhibitor.
- Chowdhury A., et al.: Etiology of gastric outlet obstruction. Am J Gastroenterol 1996; 91: pp. 1679.
- Johnson C.D.: Gastric outlet obstruction malignant until proved otherwise. Am J Gastroenterol 1995; 90: pp. 1740.
- Johnson C.D., Ellis H.: Gastric outlet obstruction now predicts malignancy. Br J Surg 1990; 77: pp. 1023-1024.
- Koop A., et al.: Gastric outlet obstruction: a red flag, potentially manageable. CCJM 2019; 86 (5):
- Shone D.N., et al.: Malignancy is the most common cause of gastric outlet obstruction in the era of H2 blockers. Am J Gastroenterol 1995; 90: pp. 1769-1770.
- Tringali A., et al.: Endoscopic management of gastric outlet obstruction disease. Ann Gastroenterol 2019; 32 (4): pp. 330-337.
- Umair I., et al.: EUS-guided gastroenterostomy for the management of gastric outlet obstruction: a systematic review and meta-analysis. Endosc Ultrasound 2020; 9 (1): pp. 16-23.