Post Gastrectomy Syndromes: Diagnosis and Treatment

What are  Post Gastrectomy Syndromes

• These are gastrointestinal and cardiovascular syndromes after gastrectomy. 20-25% of the patients undergoing surgeries for peptic ulcer disease experience post gastrectomy syndromes. 1-5% of the patients become permanently disabled due to post gastrectomy symptoms. It is divided into 3 categories:
  • Secondary to gastric resection
  • Secondary to gastric reconstruction
  • Post vagotomy syndrome
• The conditions that develop under secondary to gastric syndromes are:
  • Dumping syndrome
  • Metabolic disturbances
• The conditions that develop under the secondary to gastric reconstruction are:
  • Afferent loop syndrome
  • Efferent loop syndrome
  • Alkaline reflux gastritis
  • Retained antrum syndrome
• The conditions that develop under the post-vagotomy syndrome are:
  • Post vagotomy diarrhea
  • Post vagotomy gastric atony
  • Incomplete vagal transaction

Dumping Syndrome

It is the combination of GI and vasomotor symptoms due to rapid postprandial gastric emptying.

It is more common after partial gastrectomy with Billroth-II reconstruction. This reconstruction is a loop gastrojejunostomy. Here, there is a rapid emptying of the hyperosmolar and hyperglycemic contents into the proximal part of the jejunum.

Early dumping

The early dumping symptom is due to the rapid passage of hyperosmolar food from the stomach to the small intestine (SI). After the entry of the food, there is a rapid shift of

extracellular fluid into the intestinal lumen. There is luminal distension and also hypovolemia. So, these patients will develop vasomotor and abdominal symptoms. It is secondary to the release of serotonin, bradykinin, neurotensin and enteroglucagon. For the management, patients are asked to lie down supine and IV fluid is given.

Late dumping

Late dumping is comparatively less common. Late dumping is due to the rapid delivery of

carbohydrates into the proximal small intestine. This transport leads to the formation of hyperglycemia. This leads to increased Insulin release and results in reactive hypoglycemia. This leads to sympathetic secretion, leading to the release of catecholamines. Patients experience tachycardia, diaphoresis, light headaches and confusion. For the management, the patient should be given oral glucose.

Management of Dumping Syndrome

Dietary treatment to reduce the jejunal osmolarity:

• Patients should take small frequent meals.
• Low amount of carbohydrates and high amount of fat, protein, and fiber diet.
• Liquids are advised to be avoided during the meal.
• High-calorie drinks should be avoided.

Metabolic Disturbances

The most common metabolic defect after gastrectomy is anemia. Iron deficiency anemia is more common than megaloblastic anemia. More than 30% of patients undergoing gastrectomy develop iron deficiency anemia. It can be caused by decreased iron intake and impaired iron absorption. Fe3+ is the oral intake form of iron and Fe2+ is the absorption form of iron. Lesser acid leads to lesser conversion. 

Management: Increased oral supplementation. Megaloblastic anemia is seen in patients when more than 50% of the stomach is removed. It is seen after subtotal gastrectomy. Here is a lack of intrinsic factors secreted from the stomach wall. To counteract this condition lifelong parenteral vitamin B12 supplementation has to be given.

Osteoporosis and osteomalacia are also seen after gastrectomy due to Ca deficiency. This happens because there is fat malabsorption and that aggravated Ca malabsorption because free fatty acids bind with Calcium. Incidence increases with the extent of gastrectomy. It is usually associated with Billroth-II gastrectomy. Patients develop bone disease after 4-5 years of surgery. 

Management: calcium supplementation and vitamin D supplementation. Patients with Billroth-II gastrectomy, or Roux-en-Y reconstruction bypassing duodenum, supplements of fat soluble vitamins (A, D, E, K) should be given.

Afferent Loop Syndrome

The afferent and the efferent limbs are shown. When there is an obstruction in the afferent loop, it is called afferent loop syndrome. Obstruction in the efferent loop is known as efferent loop Syndrome. Afferent loop syndrome is more common. This occurs due to partial obstruction. For this, the afferent loop cannot empty its content. So, the pancreatic and the biliary secretions keep accumulating in the afferent limb. Because of this accumulation, there is distention. Due to this distention, there is epigastric discomfort and cramping.

Once the intraluminal pressure is raised to a certain limit, the patient will experience projectile bilious vomiting. Then, there is a relief of symptoms. When there is a long duration of obstruction, there is an increased risk of blind loop syndrome. In the static loop, due to the storage of food, there is bacterial overgrowth. It bonds with B12 and deconjugates bile acid. Because of this, patients will develop vitamin B12 deficiency. As described earlier, there is fat malabsorption here as well, so the patients will develop fat-soluble vitamin deficiency.

Diagnosis

Failure to visualize the afferent limb is the diagnosis for this syndrome. On radionuclide imaging, it does not pass into the stomach/distal bowel after being excreted into afferent limb. The problem is the long afferent limb. So, surgery should be done to prevent bowel necrosis or

duodenum intestinal blowout. The option for surgery is the conversion of Billroth-II to

Billroth-I. Enteroenterostomy can be done between afferent and efferent loops. Conversion to Roux-en-Y reconstruction.

Efferent Loop Obstruction

Efferent loop obstruction is rare. It may occur at any time after surgery. In more than 50% of cases, it is going to occur in the first postoperative month. Patients experience left upper quadrant colicky pain. The other clinical features are bilious vomiting and abdominal distention.

Diagnosis

• It can be made by upper GI series.
• CT can do it with oral contrast.
• As there is an obstruction in the efferent limb, the contrast does not enter the efferent limb.

Treatment

Surgery should be done to reduce the retroanastomotic hernia and to close the retro-anastomosing space.

Alkaline Reflux Gastritis

There is reflux of bile into the stomach, leading to alkaline reflux gastritis. It is seen in Billroth-II gastrectomy. Because of this reflux, there is gastritis, and patients experience severe epigastric pain. Some patients also experience bilious vomiting and weight loss as well.

Diagnosis and Treatment

The diagnosis is typically made based on a patient's history. In TC-biliary scan, reflux of bile into the stomach is seen. Endoscopy shows Friable, Beefy Red Mucosa. There is no correlation between the volume and the composition of the bile to the development of alkaline reflux

Gastritis. For patients with intractable symptoms, the treatment choice is surgery. The surgical procedure of choice is Billroth-II into Roux-en- Y gastrojejunostomy. The length of the Roux limb should be more than 40 cm. To reduce the risk of alkaline reflux gastritis, Roux-en-Y is a preferred surgery over the Billroth II procedure.

Gastric Atony

Delayed gastric emptying after truncal vagotomy (TV) or selective vagotomy (SV). After SV or TV, there is a loss of antral pump function, which\ reduces the ability to empty solids. On the other hand, the emptying of liquid is accelerated because of the loss of receptive relaxation in the proximal stomach. The clinical features include:

Retention of food in the stomach for a longer period. Patients experience a fullness of the stomach and abdominal pain.

Diagnosis

This condition is diagnosed by Scintigraphic assessment of gastric emptying. An endoscopy is done to rule out anastomotic obstruction.

Management

For patients having functional gastric outlet obstruction and documented gastroparesis, pharmacotherapy is used. The most commonly used prokinetic agents are Metoclopramide and erythromycin. Metoclopramide is a Dopamine agonist and facilitates the acetylcholine release from the enteric cholinergic neurons. Erythromycin is a motilin agonist and accelerates gastric

emptying by binding to the motilin receptors on the Gi smooth muscle cells. In cases of persistent cases refractory to treatment, then gastrectomy is the treatment of choice.

Also read: Super Speciality in Surgical Gastroenterology

Propel your NEET SS Surgery Preparation! Access conceptual video lectures, QBank, Mock Tests, and premium study resources on the PrepLadder App. Download the PrepLadder app now to access high-yield content with 24-hr Free Trial.