Postgastrectomy Syndrome

Postgastrectomy syndrome is a group of functional, nutritional and mechanical disorders caused by loss of gastric reservoir function, altered gastric emptying, vagal denervation and reconstruction of gastrointestinal continuity.

The major syndromes include:

• Dumping syndrome
• Bile reflux gastritis
• Roux stasis syndrome
• Afferent loop syndrome
• Efferent loop obstruction
• Postvagotomy diarrhoea
• Small intestinal bacterial overgrowth
• Iron, vitamin B12, calcium and vitamin D deficiency
• Weight loss and protein calorie malnutrition

The diagnosis should identify the specific syndrome rather than labelling all symptoms after gastrectomy as a generic postoperative problem.

The symptom pattern usually suggests the mechanism.

Rapid postprandial vasomotor symptoms: dumping syndrome.

Bilious vomiting and burning epigastric pain: bile reflux.

Early satiety, fullness, nausea and food retention after Roux reconstruction: Roux stasis.

Postprandial upper abdominal pain followed by bilious vomiting that relieves the pain: consider afferent loop syndrome.

Progressive vomiting with inability to tolerate intake: mechanical obstruction until proven otherwise.

Long term consequences include weight loss, iron deficiency anaemia, vitamin B12 deficiency, metabolic bone disease and micronutrient deficiencies.

After total gastrectomy, loss of intrinsic factor makes lifelong vitamin B12 supplementation necessary.

Investigations should follow the symptom pattern.

Upper gastrointestinal endoscopy: evaluate anastomotic stricture, bile reflux, ulceration, recurrent malignancy and retained food.

CT abdomen: use when afferent loop obstruction, internal hernia, recurrent cancer or mechanical obstruction is suspected.

Check full blood count, ferritin, vitamin B12, folate, calcium, phosphate, magnesium, vitamin D and other micronutrients according to anatomy and symptoms.

Management is syndrome specific.

Nutritional rehabilitation

Use small frequent meals with adequate protein and dietitian input.

After total gastrectomy, lifelong micronutrient surveillance and supplementation is necessary.

A practical vitamin B12 regimen is:

Cyanocobalamin 1000 micrograms IM every month

or sufficiently high dose oral or sublingual replacement where local practice and monitoring support it.

Use calcium citrate approximately 1200 to 1500 mg elemental calcium daily, divided into doses no greater than approximately 500 mg at one time.

Vitamin D is titrated to serum 25 hydroxyvitamin D, with at least 1000 IU daily often required and larger doses used when deficiency is established.

Iron replacement should be guided by ferritin and haemoglobin. Intravenous iron may be required when oral treatment is ineffective or poorly tolerated.

Bile reflux

Begin with dietary adjustment and mucosal protection. A proton pump inhibitor may help coexisting acid mediated symptoms but does not neutralise bile itself.

Persistent severe bile reflux after Billroth reconstruction may require conversion to a Roux en Y reconstruction when medical therapy fails.

Roux stasis

Exclude mechanical obstruction first.

Use smaller meals and reduce medications that impair motility.

Metoclopramide may be tried short term:

Metoclopramide 10 mg orally or IV up to three times daily before meals, usually for the shortest feasible duration because of extrapyramidal and tardive dyskinesia risk.

Afferent loop syndrome

Acute complete obstruction is a surgical emergency because rapidly increasing biliopancreatic pressure can cause ischaemia, perforation, pancreatitis or cholangitis.

Definitive treatment corrects the anatomical obstruction, often by surgical reconstruction or endoscopic intervention depending on anatomy and cause.

Reoperation should target a defined anatomical problem rather than nonspecific postoperative symptoms.