Postgastrectomy complications

INTRODUCTION — Various forms of gastric resection and reconstruction are used to manage a variety of benign and malignant conditions of the stomach. Similar to any other abdominal surgery, gastric surgery can result in postoperative complications. Although complications are considerably less common today, historical data would suggest that approximately one in four patients reports significant symptoms after gastric surgery; in 2 to 5 percent, these symptoms are disabling [1].

The complications specific to gastric surgery will be reviewed in this topic. Complications common to all abdominal surgeries, such as bleeding, infection, bowel obstruction, fascia dehiscence, or hernia, are discussed in another topic (see "Complications of abdominal surgical incisions"). Complications of bariatric surgical procedures (eg, Roux-en-Y gastric bypass or sleeve gastrectomy) are discussed elsewhere. (See "Bariatric operations: Early (fewer than 30 days) morbidity and mortality" and "Bariatric operations: Late complications with acute presentations" and "Bariatric operations: Late complications with subacute presentations".)

POSTGASTRECTOMY ANATOMY — The derangements in gastrointestinal function that occur following gastric resection depend upon the portion and volume of gastric tissue removed and the type of reconstruction.

Gastric resection — Gastric resections include (see "Partial gastrectomy and gastrointestinal reconstruction" and "Total gastrectomy and gastrointestinal reconstruction"):

●Partial gastrectomy (proximal or distal)

●Total gastrectomy

Reconstruction — Reconstructive techniques include (figure 1 and figure 2) (see "Total gastrectomy and gastrointestinal reconstruction" and "Partial gastrectomy and gastrointestinal reconstruction", section on 'Gastrointestinal reconstruction'):

●Billroth I

●Billroth II

●Roux-en-Y

●Esophagojejunostomy

DIAGNOSING POSTGASTRECTOMY COMPLICATIONS — Complications should be suspected in postgastrectomy patients who complain of severe or persistent gastrointestinal symptoms such as epigastric pain, nausea, vomiting, early satiety, bloating, diarrhea, or weight loss.

The initial evaluation for the majority of patients presenting with postoperative gastrointestinal symptoms is abdominal computed tomography (CT).

●Acute abdomen – In the early postoperative period, patients could develop symptoms of an acute abdomen (including peritonitis, fever, tachycardia, or hypotension) secondary to an anastomotic or duodenal stump leak. Such patients should undergo abdominal CT. Upper gastrointestinal series with water-soluble contrast is a second choice but usually unnecessary. Although endoscopic approaches to management are being employed in some patients, this is a therapeutic and not a diagnostic maneuver. (See 'Leak' below.)

●Obstructive symptoms – Patients with acute obstructive symptoms (eg, epigastric pain, nausea, or vomiting) should likewise undergo abdominal CT. Abdominal CT is diagnostic of complications that can lead to upper gastrointestinal tract obstruction, such as afferent or efferent loop syndrome, jejunal intussusception, or internal hernia. Patients who present with chronic or intermittent obstruction symptoms may also undergo upper gastrointestinal series with barium contrast, which is diagnostic of anastomotic stricture and can also identify marginal ulceration, remnant cancer, and alkaline reflux gastritis. (See 'Obstruction' below.)

●Chronic dysmotility – Patients with symptoms suggestive of a motility problem (early satiety and bloating, postprandial vomiting or diarrhea, weight loss) typically first undergo abdominal CT and upper endoscopy to rule out mechanical complications such as an obstruction. Nuclear medicine studies then follow to make the definitive diagnoses of functional complications. A solid food gastric emptying study is diagnostic of gastric stasis and Roux stasis syndrome. Technetium biliary scan may be used to identify alkaline gastritis. (See 'Slow transit' below.)

●Dumping syndrome – Patients with dumping syndrome present with gastrointestinal discomfort, including nausea, vomiting, cramps, and diarrhea, as well as vasomotor symptoms such as diaphoresis, palpitations, and flushing 15 to 30 minutes after a meal. The diagnosis of dumping syndrome is made primarily on clinical grounds, supported by tests such as upper gastrointestinal series and gastric emptying studies. (See 'Dumping syndrome' below.)

COMPLICATIONS RELATED TO ANASTOMOSIS — Anastomotic complications in postgastrectomy patients include anastomotic leak, anastomotic stricture, and anastomotic ulceration. In addition, postgastrectomy obstruction can occur anatomically at the level of the gastrointestinal anastomosis or a short distance away from the anastomosis (eg, afferent or efferent loop).

Leak — Postoperative leak can arise from any of the suture or staple lines, including the jejunojejunal anastomosis of a Roux-en-Y [2]. An anastomotic leak most commonly occurs within the first 7 to 10 days after surgery. Patients present with fever, unexplained tachycardia and/or hypotension, abdominal pain, and/or an acute abdomen. If an anastomotic leak is suspected, CT should be obtained, which may show indirect evidence of a leak, such as pneumoperitoneum, extraluminal contrast, inflammatory stranding, fluid collections, and/or abscess. Contrast studies, such as an upper gastrointestinal series with Gastrografin, may show the leak directly. (See "Overview of gastrointestinal tract perforation", section on 'Diagnosis'.)

When an anastomotic leak is confirmed, broad-spectrum antibiotics are initiated. Further management of the leak will depend on the state of the patient and availability of an interventional radiologist to perform a percutaneous drainage procedure. Contained collections in an otherwise stable patient may be amenable to percutaneous drainage [3]. The aim of percutaneous drainage is to create a controlled enterocutaneous fistula to allow the leak to heal over time.

If nonoperative management is unsuccessful at controlling the leak, the patient is hemodynamically unstable, or diffuse intra-abdominal contamination is suspected, the patient is taken to the operating room for exploration, drainage, and anastomotic revision to prevent or control abdominal sepsis. Although there is some experience with stenting such leaks, most of this has been done after gastric surgery for obesity (see "Gastrointestinal endoscopy in patients who have undergone bariatric surgery", section on 'Anastomotic leak and fistula'). Once the leak is definitively controlled, antibiotic therapy can be tailored according to microbial sensitivities of cultures obtained at the time of either percutaneous drainage or operative intervention.

Duodenal stump leak — The most feared anastomotic complication following partial gastrectomy is a breakdown of the duodenal stump closure, or duodenal stump leak, following a Billroth II or Roux-en-Y type of procedure (figure 1). The most important goal of treatment of duodenal stump leak is control of sepsis and drainage of the surgical bed. In addition to carrying out the routine surgical management of an anastomotic leak (as described above), the surgeon may decide to insert a tube duodenostomy, if feasible, depending upon the extent of inflammation. (See "Management of duodenal trauma in adults", section on 'Repair of duodenal injury'.)

Stricture — The Billroth II reconstruction (figure 1) is susceptible to postsurgical scarring at the gastrojejunostomy site, resulting in gastric outlet obstruction characterized by chronic or intermittent bloating with nonbilious vomiting [2]. A stricture is typically diagnosed by upper gastrointestinal series with special attention to the lateral views. If a stricture is found on fluoroscopy, endoscopic evaluation with biopsies is warranted to rule out recurrent cancer. Benign strictures can be treated by dilation, which may need to be repeated on several occasions. Stenting might also be considered. (See "Gastrointestinal endoscopy in patients who have undergone bariatric surgery", section on 'Stomal (anastomotic) stenosis'.)

Anastomotic stricture is also seen in 6 to 20 percent of patients who undergo Roux-en-Y gastric bypass for weight loss (figure 3) [4]. These patients are managed similarly to patients with strictures after Billroth II reconstruction with endoscopic dilation. (See "Bariatric operations: Late complications with acute presentations", section on 'Stomal stenosis'.)

Obstruction — Postgastrectomy obstruction can occur at or a distance away from the gastrointestinal anastomosis. Regardless of the level of obstruction, patients typically present with nausea, vomiting, early satiety, and/or epigastric abdominal pain, with progression to intolerance of oral intake. The diagnosis may be suspected based upon presenting clinical features and physical examination and is confirmed by radiologic evaluation and/or endoscopy. The diagnosis of gastric outlet obstruction is reviewed in more detail separately. (See "Gastric outlet obstruction in adults", section on 'Evaluation'.)

Afferent and efferent loop syndrome — Afferent and efferent loop syndromes can develop after Billroth II reconstruction with a gastrojejunostomy (see "Partial gastrectomy and gastrointestinal reconstruction", section on 'Billroth II'). They are related to mechanical obstruction of the loops by kinking, anastomotic narrowing, adhesions, or, rarely, anastomotic ulceration (figure 4) [5].

The afferent loop refers to the duodenojejunal loop proximal to the gastrojejunal anastomosis (figure 5). It is believed that many of these are related to excessive length of the afferent loop; afferent loop syndrome may be prevented by keeping the distance from the ligament of Treitz to the gastrojejunostomy <12 to 15 cm. A patient with an acute afferent loop obstruction presents with acute onset of severe abdominal pain and vomiting, which requires immediate operation to prevent bowel necrosis or duodenal blowout [6]. Chronic afferent loop syndrome is typically associated with postprandial epigastric pain and intermittent projectile bilious vomiting, which leads to resolution of the pain for a period of up to several days. In patients suspected of having afferent loop syndrome based upon symptoms (eg, intermittent projectile bilious vomiting), the detection of a distended afferent loop on abdominal CT is diagnostic. Surgical revision of the gastrojejunostomy or conversion to a Roux-en-Y anastomosis is necessary to treat this problem. Alternatively, a Braun's enteroenterostomy between the afferent and efferent loops may also decompress the afferent loop (figure 6) [5].

The efferent loop refers to the jejunal segment distal to the gastrojejunostomy that drains succus entericus away from the stomach (figure 5). Obstruction of the efferent loop causes gastric outlet obstruction manifested by symptoms of epigastric pain, distension, and bilious vomiting. When diagnosed by either CT or upper gastrointestinal series, surgical correction is the treatment of choice for efferent loop syndrome.

Jejunal intussusception — Although uncommon, the afferent or efferent loop of a Billroth II reconstruction can intussuscept into the gastric remnant through the gastrojejunal anastomosis (jejunogastric intussusception) (figure 7). This unusual cause of gastric outlet obstruction can cause acute-onset bloating and bloody vomiting in postgastrectomy patients [2].

Intussusception can be seen on abdominal CT, upper gastrointestinal series, or endoscopy. On upper intestinal series, there is narrowing of the distal end of the gastric remnant with an unopacified, coil-like distention into the proximal jejunum (image 1). Jejunal intussusception is generally not reducible; therefore, surgical resection of the intussuscepting small bowel followed by revision of the gastrojejunostomy or conversion to a Roux-en-Y reconstruction is necessary.

Internal hernia — Internal hernias can cause gastrointestinal obstruction after a Billroth II or Roux-en-Y gastrectomy. Patients with internal hernias usually present with acute abdominal pain with or without abdominal distention or vomiting. Diagnosis is made by CT. Early surgical intervention is necessary to avoid small bowel infarction as internal hernias often cause closed-loop small bowel obstruction. Internal hernias can be prevented at the time of gastric surgery by careful closure of all mesenteric defects. Specifically, the mesocolon should be sutured to the stomach at the gastrojejunostomy, and the space between the mesentery of the retrocolic jejunal limb and mesocolon (ie, Peterson's defect) needs to be closed. (See "Bariatric operations: Late complications with acute presentations", section on 'Small bowel obstruction'.)

Marginal ulcer — After gastric surgery, patients can develop ulcers in the remnant stomach, duodenum, or jejunum [2,5]. The most common ulcers, marginal ulcers, occur in the jejunum distal to the gastrojejunal anastomosis. The diagnosis and treatment of marginal ulcers after Roux-en-Y gastric bypass surgery for weight loss are discussed elsewhere. (See "Bariatric operations: Late complications with acute presentations", section on 'Marginal ulcers'.)

In patients who have had peptic ulcer surgery, recurrent ulceration of the stomach or duodenum may signal incomplete vagotomy, retained gastric antrum, Zollinger-Ellison syndrome (ie, gastrinoma), nonsteroidal anti-inflammatory drug (NSAID) use, Helicobacter pylori infection, or cancer. The diagnostic evaluation and treatment of recurrent ulcer disease is discussed separately. (See 'Peptic ulcer' below and "Approach to refractory peptic ulcer disease", section on 'Management' and "Approach to refractory peptic ulcer disease", section on 'Address the etiology and risk factors'.)

COMPLICATIONS RELATED TO MOTILITY — Following partial gastric resection, alterations in upper gastrointestinal function inevitably occur because duodenal or jejunal continuity is lost and the ability of the stomach remnant to function as a reservoir is impaired (table 1). Termed postgastrectomy syndromes, these alterations occur in characteristic patterns depending upon the extent of gastric resection and the type of gastric reconstruction. (See "Partial gastrectomy and gastrointestinal reconstruction", section on 'Gastrointestinal reconstruction'.)

Rapid transit — The most common symptom that postgastrectomy patients with rapid transit report is diarrhea. In the postgastrectomy period, diarrhea may be due to dumping syndrome or postvagotomy diarrhea.

Dumping syndrome — Dumping is a phenomenon usually caused by the destruction or bypass of the pyloric sphincter. Clinically significant dumping symptoms occur in about 20 percent of patients after pyloroplasty or distal gastrectomy [7]. Although the precise mechanism of dumping is incompletely understood, the syndrome is frequently attributed to the rapid emptying of hyperosmolar chyme (particularly carbohydrates) into the small bowel [8]. The osmotic gradient is believed to draw fluid into the intestine, and this may release one or more vasoactive hormones, such as serotonin and vasoactive intestinal polypeptide. (See "Bariatric operations: Late complications with subacute presentations", section on 'Dumping syndrome'.)

●Clinical presentation

•Early dumping – About 15 to 30 minutes after a meal, affected patients develop gastrointestinal discomfort, including nausea, vomiting, cramps, and diarrhea, as well as vasomotor symptoms such as diaphoresis, palpitations, and flushing [9,10]. These symptoms are referred to as early dumping, or simply dumping syndrome.

•Late dumping – Less often, patients complain of the same constellation of symptoms hours after eating, the so-called late dumping syndrome. This phenomenon is not strictly due to alterations of osmotic gradients across the gastrointestinal (GI) tract but rather is thought to result from hypoglycemia following a postprandial insulin peak. (See "Evaluation of postprandial symptoms of hypoglycemia in adults without diabetes".)

●Diagnosis – A suggestive pattern of symptoms in a patient who has undergone gastric surgery should raise the possibility of dumping syndrome. The diagnosis of dumping syndrome is made primarily on clinical grounds [11]. A monitored glucose challenge, upper GI series, or gastric emptying studies have been used to support the diagnosis.

●Treatment – Most patients with dumping can be treated conservatively with dietary changes (frequent small meals that are high in fiber and protein and low in carbohydrates, separation of liquid from solid during meals) [9,10]. Symptoms tend to resolve in most patients as they learn to avoid foods that aggravate the problem (eg, simple sugar).

Octreotide may also help in severe cases of dumping but is rarely required [8]. A study of 30 patients with dumping treated with either subcutaneous octreotide, administered three times a day, or its long-acting formulation (Octreotide LAR), which is given monthly, reported that both significantly reduced dumping symptoms and improved quality of life [12]. Patients preferred monthly treatment.

The rare patient with intractable dumping symptoms who fails dietary and medical therapy may require reoperation [9,10]. In patients who had a distal gastrectomy, conversion from a loop gastrojejunostomy to a Roux-en-Y reconstruction is the procedure of choice. This operation slows gastric emptying by impairing motility of the Roux loop. A gastric remnant of no more than 25 percent should be left to avoid postoperative Roux stasis syndrome. (See 'Roux stasis syndrome' below.)

Postvagotomy diarrhea — Diarrhea develops in approximately 30 percent of patients after truncal vagotomy [7]. The pathogenesis is unclear, but it may be related to the rapid passage of unconjugated bile salts from the denervated biliary tree into the colon, where they stimulate secretion. Most cases are self-limited. Oral cholestyramine, which binds bile salts, can be effective in persistent cases. If medical therapy fails, the surgical option used in the past is to place a 10 cm reversed (antiperistaltic) jejunal loop in continuity 100 cm distal to the ligament of Treitz; this is rarely needed today.

Slow transit — Postgastrectomy patients with slow transit often present with symptoms of nausea, vomiting (bilious or nonbilious), epigastric pain or bloating, and early satiety, leading to weight loss over time. The differential diagnosis of these symptoms includes gastric stasis, alkaline gastritis, and Roux-stasis syndrome.

Gastric stasis — After gastric surgery, impaired gastric emptying may develop as a result of postsurgical atony or vagal denervation, or from a small gastric remnant [5]. Symptoms consist of epigastric fullness with meals (early satiety), often followed by emesis of undigested food, abdominal pain, and weight loss.

The evaluation of a patient suspected of postgastrectomy gastric stasis syndrome begins with an upper GI series with small bowel series to define postsurgical anatomy and rule out mechanical obstruction. Upper endoscopy is also typically performed to rule out anastomotic strictures or marginal ulcers, which could cause or exacerbate gastric stasis. Upper endoscopy can also disimpact food bezoars, which are commonly found in chronic gastric stasis patients [13] (see "Gastric bezoars"). Impaired gastric emptying is best diagnosed quantitatively with a nuclear medicine solid food emptying test.

Symptoms attributed to a small gastric remnant will usually improve with small, frequent feedings and time to allow the remnant stomach to accommodate. Postoperative gastric atony may respond to prokinetic agents such as metoclopramide and erythromycin. Although there is some evidence that gastric pacing may improve the symptoms of primary gastroparesis, its widespread clinical use has not been yet achieved. (See "Treatment of gastroparesis" and "Electrical stimulation for gastroparesis".)

If dietary and medical therapies fail, reoperative gastrectomy may be required. Patients without prior partial gastrectomy should undergo subtotal (75 percent) gastrectomy; patients with prior partial gastrectomy should undergo near-total (95 percent) gastrectomy or total gastrectomy with esophagojejunostomy [14]. A Billroth II reconstruction with a Braun enteroenterostomy may be preferred to a Roux-en-Y reconstruction because of potential Roux stasis syndrome associated with the latter (figure 6). (See 'Roux stasis syndrome' below.)

Alkaline gastritis — Reflux of bile into the stomach is common after operations that remove or bypass the pylorus. In most patients, there are no serious clinical sequelae [5,15]. However, approximately 2 percent of patients develop alkaline reflux gastritis, a syndrome of persistent burning epigastric pain and chronic nausea that is aggravated by meals. The diagnosis is made primarily by excluding other causes of symptoms, although endoscopy may reveal gastritis, and technetium biliary scan can demonstrate excessive reflux of bile into the stomach.

A variety of medical therapies for alkaline gastritis have been reported, but none have proven particularly effective (see "Acute hemorrhagic erosive gastropathy and reactive gastropathy"). Surgical therapies aim at separating the remnant stomach from duodenal content by interposing a loop of jejunum between them. Examples include Roux-en-Y reconstruction (with a 45 to 60 cm Roux loop), Henley loop (interposition of a 40 cm isoperistaltic jejunal loop between the gastric remnant and the duodenum), and Billroth II reconstruction with Braun enteroenterostomy (positioned 45 to 60 cm from the gastrojejunal anastomosis). The reoperative procedure is chosen based upon a patient's existing anatomy and how much remnant stomach is left [5].

Roux stasis syndrome — Roux-en-Y reconstruction is typically performed as the primary reconstruction after near-total or total gastrectomy. It is also used as reoperative treatment for patients with intractable dumping syndrome, severe alkaline gastritis, or afferent loop syndrome. (See 'Dumping syndrome' above and 'Alkaline gastritis' above and 'Afferent and efferent loop syndrome' above.)

After undergoing Roux-en-Y reconstruction, a subset of patients develop symptoms of vomiting, epigastric pain, and weight loss (ie, Roux stasis syndrome). Roux stasis syndrome is thought to be caused by disordered motility of the Roux loop with net propulsive activity toward, instead of away from, the stomach. Patients suspected of Roux stasis syndrome should undergo evaluation with upper GI series, upper endoscopy, and nuclear medicine gastric emptying study [16]. The findings are similar to those with gastric stasis (see 'Gastric stasis' above). One important exception is the finding of a dilated, often flaccid Roux loop.

Medical treatment of Roux stasis syndrome consists of prokinetic agents such as metoclopramide and erythromycin. When medical therapy fails, surgical therapy consists of resecting the exiting Roux loop and replacing it with a new Roux-en-Y reconstruction. To prevent recurrence, further resection of the remnant stomach (near-total, or 95 percent gastrectomy) is also carried out. Because Roux stasis syndrome is seen more often in patients with a generous (over 50 percent) gastric remnant, as well as in patients with truncal vagotomy, alternative reconstructive techniques such as Billroth II reconstruction with or without Braun enteroenterostomy should be used to avoid Roux-stasis syndrome, when feasible (figure 6) [5].

Gallstones — Gallstones can develop after gastrectomy for cancer due to cholestasis, which is caused by decreased gallbladder contraction from various mechanisms, including weight loss, vagotomy, lymph node dissection in the hepatogastric ligament, and nonphysiologic reconstruction [17].

In one trial, the proportion of patients developing gallstones within 12 months after gastrectomy was reduced with daily ursodeoxycholic acid (5.3 percent in the 300 mg group, 4.3 percent in the 600 mg group), compared with placebo (16.7 percent) [18].

LONG-TERM COMPLICATIONS INVOLVING REMNANT STOMACH — Following partial gastrectomy, the remnant stomach is susceptible to developing ulcer disease or cancer. Depending upon the indication for the initial operation, these ulcers or cancer can be de novo or recurrent.

Peptic ulcer — Gastric or duodenal ulcers can recur because of surgical or medical reasons [19]. In postgastrectomy patients, retained gastric antrum and incomplete vagotomy are the two main surgical causes of recurrent peptic ulcer disease. Patients who had Billroth II gastrectomy can have retained gastric antrum left on the duodenal margin. Because it is out of the acid stream, the retained gastric antrum secretes an excessive amount of gastrin, which in turn hyperstimulates gastric acid production, causing ulceration. In patients with incomplete vagotomy, vagal stimulation of gastric acid production is not completely abolished, which results in hyperacidity and recurrent peptic ulcer.

To rule out retained gastric antrum, we typically measure a fasting serum gastrin level. A high level of gastrin can stimulate overproduction of gastric acid. A secretin test is then required to differentiate between retained gastric antrum and Zollinger-Ellison syndrome as the cause for hypergastrinemia. Retained gastric antrum is diagnosed by an elevated fasting serum gastrin level that is suppressed by intravenous secretin administration. In contrast, serum gastrin level rises further with secretin in Zollinger-Ellison syndrome patients (see "Zollinger-Ellison syndrome (gastrinoma): Clinical manifestations and diagnosis", section on 'Secretin stimulation test'). Treatment for retained gastric antrum is surgical resection.

If serum gastrin is not elevated, one may measure gastric acid output at baseline and after a sham feeding in order to rule out incomplete vagotomy. Compared with basal acid output, a large increase in acid output stimulated by sham feeding suggests incomplete vagotomy. Patients with incomplete vagotomy can usually be treated with a proton pump inhibitor, although in the past, thoracoscopic truncal vagotomy was also used [20]. (See "Vagotomy".)

Postgastrectomy patients who present with peptic ulcer disease also require an evaluation to assess for medical causes. These include medications (eg, nonsteroidal anti-inflammatory drugs), H. pylori infection, Zollinger-Ellison syndrome, and gastric remnant cancer. The evaluation for medical causes of peptic ulcer disease is reviewed separately. (See "Approach to refractory peptic ulcer disease".)

Remnant cancer — Patients with a previous partial gastrectomy for benign diseases are at an increased risk for developing gastric cancer [21]. These gastric remnant or "stump" carcinomas generally involve the distal extent of the gastric remnant near the gastrojejunal anastomosis [22]. Chronic reflux of bile and pancreatic secretions leading to chronic inflammation is thought to play a role.

Reported frequencies of gastric remnant carcinoma range from 0.8 to 8.9 percent [23-31]. Endoscopic screening studies have detected gastric cancer in 4 to 6 percent of partial gastrectomy patients over time. However, this increased risk has not been uniformly reported [32,33]. Studies that have demonstrated an increased risk of gastric remnant cancer suggest that the risk appears to increase 15 to 20 years after the initial surgery [24,26-28,31,34].

Because a benefit has not been established, endoscopic surveillance of postgastrectomy patients is not mandatory. However, if surveillance endoscopy is considered, it is typically initiated after an interval of 15 to 20 years from the time of gastric surgery. At the time of endoscopy, multiple biopsies from the anastomosis and gastric remnant should be taken. With or without surveillance, postgastrectomy patients should also undergo prompt endoscopic evaluation for any significant upper gastrointestinal symptoms (eg, nausea, vomiting, early satiety, abdominal pain).

NUTRITIONAL DEFICIENCIES — The surgeon should be aware of possible nutritional deficiencies that can develop following partial gastrectomy, including malabsorption of vitamins or minerals (table 2) [35-38]. Nutritional deficiencies following gastric resection are similar to those that can manifest following gastric surgery to manage obesity, which is discussed elsewhere. (See "Bariatric surgery: Postoperative nutritional management".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Gastric surgery for cancer".)

SUMMARY AND RECOMMENDATIONS

●Etiologies of complications – Complications unique to postgastrectomy patients can be related to the anastomosis or motility and can also occur in the remnant stomach. The derangements in gastrointestinal function that occur following gastric resection depend upon the portion and volume of gastric tissue removed and the type of reconstruction. (See 'Postgastrectomy anatomy' above.)

●Diagnosing complications – Complications should be suspected in postgastrectomy patients who complain of gastrointestinal symptoms of epigastric pain, nausea, vomiting, early satiety, bloating, or weight loss. Most of these patients are evaluated with abdominal CT, upper gastrointestinal series, and/or upper endoscopy. (See 'Diagnosing postgastrectomy complications' above.)

●Anastomotic leaks – Anastomotic leak should be suspected in patients who present acutely with severe abdominal pain, fever, or hemodynamic instability. Once diagnosed by upper gastrointestinal series or CT scan, urgent surgical intervention or percutaneous drainage is required to control the leak and drain any intra-abdominal sepsis. (See 'Leak' above.)

●Anastomotic strictures – Anastomotic strictures should be suspected in patients who complain of bloating and nonbilious vomiting. Once diagnosed by upper gastrointestinal series, endoscopic dilation is the treatment of choice. (See 'Stricture' above.)

●Gastrointestinal obstruction – Obstruction can occur because of afferent/efferent loop syndrome, jejunal intussusception, or internal hernia. Patients typically present with nausea, vomiting, early satiety, and/or epigastric abdominal pain, with progression to intolerance of oral intake. Once the etiology is diagnosed by CT scan, the treatment is usually surgical. (See 'Obstruction' above.)

●Dumping syndrome – Dumping is a phenomenon caused by the destruction or bypass of the pyloric sphincter. Dumping symptoms include gastrointestinal discomfort (eg, nausea, vomiting, cramps, and diarrhea) as well as vasomotor symptoms (eg, diaphoresis, palpitations, and flushing). Dietary (carbohydrate avoidance) therapies work well for dumping syndrome, with only rare patients requiring medical (octreotide) therapies or referral for surgery (Roux-en-Y reconstruction). (See 'Dumping syndrome' above.)

●Gastric stasis – Gastric stasis, which is the more common slow transit complication, may develop as a result of postsurgical atony, vagal denervation, or from a small gastric remnant following surgical resection. Symptoms consist of epigastric fullness with meals (early satiety), often followed by emesis of undigested food, abdominal pain, and weight loss. Once diagnosed by upper gastrointestinal series, upper endoscopy, and gastric emptying study, dietary and medical (prokinetic agents) therapies are initiated. Intractable patients require completion near-total or total gastrectomy. Other complications related to slow transit include alkaline gastritis and Roux stasis syndrome. (See 'Slow transit' above.)

●Peptic ulcer disease – In patients who develop peptic ulcer following gastric surgery, possible etiologies include retained gastric antrum and incomplete vagotomy. Retained gastric antrum is diagnosed by an elevated serum gastrin level that is suppressed by secretin. Incomplete vagotomy is diagnosed by documenting a significant increase from baseline in gastric acid output following a sham feeding. Treatment for both conditions is surgical resection. (See 'Peptic ulcer' above.)

●Remnant gastric cancer – Patients with a previous partial gastrectomy for benign diseases are at an increased risk for developing gastric cancer after 15 to 20 years. Endoscopic surveillance is required to diagnose gastric remnant cancer in otherwise asymptomatic patients. Treatment is by surgical resection. (See 'Remnant cancer' above.)

●Nutritional deficiencies – The surgeon should be aware of possible nutritional deficiencies that can develop following partial gastrectomy, including malabsorption of vitamins or minerals (table 2). (See "Bariatric surgery: Postoperative nutritional management".)