TABLE 28-1 Complications of Gastric Surgery
Gastrectomy usually means removal of part of the stomach and anastomosis of the gastric remnant with either the duodenum (Billroth I) or a loop of proximal jejunum (Billroth II) (see Chapter 24). These operations typically are performed as surgical treatment of peptic ulcer disease or cancer of the stomach. Rarely, the entire stomach is removed.
Removal of part or all of the stomach can be associated with a variety of consequences and complications (Table 28-1). These may range in severity from a simple inability to eat large meals, due to loss of the reservoir function of the stomach, to more serious complications, such as severe dumping and profound nutritional sequelae.
I. DUMPING SYNDROME
The dumping syndrome develops as a result of the loss of pyloric regulation of gastric emptying. Thus, strictly speaking, a portion of the stomach does not necessarily have to be removed; a pyloroplasty alone can lead to the dumping syndrome. After a pyloroplasty or an antrectomy, hyperosmolar food is “dumped” rapidly into the proximal small intestine.
During the early phase of the dumping syndrome, the hyperosmolar small-bowel contents draw water into the lumen, stimulate bowel motility, and release vasoactive agents, such as serotonin, bradykinin, neurotensin, substance P, and vasoactive intestinal peptide from the bowel wall. Patients experience abdominal cramps, diarrhea, sweating, tachycardia, palpitations, hypotension, and light-headedness. These effects typically occur within 1 hour after eating.
In the late phase, because of the absorption of a large amount of glucose after the meal, plasma insulin rises excessively and blood sugar may plummet. Consequently, the patient may experience tachycardia, light-headedness, and sweatiness 1 to 3 hours after a meal.
The typical symptoms and signs in the setting of gastric surgery usually are sufficient to make the diagnosis of dumping syndrome. A blood sugar determination several hours after a meal when symptoms are at their worst may be helpful in confirming the late phase.
Patients are advised to eat small meals six to eight times a day. Carbohydrates are restricted to minimize glucose absorption. Medications to reduce bowel motility, such as diphenoxylate or loperamide, may be helpful. In rare instances, surgical revision with anastomosis of the gastric remnant to an antiperistaltic segment of jejunum may be necessary.