Monday 26 December 2016

What is a gastrectomy? |


Indications and Procedures

The stomach is an important organ in the gastrointestinal system. It receives the food that has been swallowed from the esophagus and immediately begins to process it. The stomach produces and secretes gastric juices, which include hydrochloric acid and an enzyme called pepsin for digestion
. As the stomach collects it, food is churned and mixed with the gastric fluid before it is passed to the first region of the small intestine, the duodenum. Occasionally, the stomach becomes cancerous or has an ulcer that will not heal and thus must be surgically removed.



Complete removal of the stomach, a total gastrectomy, is a relatively rare operation usually performed to treat stomach cancer

. Partial gastrectomy, however, in which only the diseased portion of the stomach is removed surgically, is fairly common. A partial gastrectomy is often performed to treat a peptic ulcer that fails to heal after medical treatment. Peptic ulcers
, which include gastric and more commonly duodenal ulcers, may not respond to drug therapy and can place the patient at risk for bleeding into the gastrointestinal tract or even complete perforation of the stomach or duodenal wall. Therefore, the indications for gastrectomy include perforation, obstruction, massive bleeding, and severe abdominal pain.


Gastrectomy requires hospitalization, general anesthesia, and postoperative care. An anesthesiologist will administer a general anesthetic, rendering the patient unconscious and insensible to pain during the operation. A nasogastric tube is passed into the stomach via the nose and nasal cavity so that any stomach contents can be removed using suction before an incision is made into the stomach.


During total gastrectomy, the whole stomach is removed and the esophagus is attached to the jejunum. The two most common types of partial gastrectomy surgeries are the Billroth I and Billroth II. A surgeon performing a Billroth I will remove the diseased part of the stomach and attach the remaining healthy stomach to the duodenum. The Billroth I is also known as gastroduodenostomy. This operation preserves most of the digestive functions. Billroth II gastrectomy requires the surgeon to perform a gastrojejunostomy in which the remaining stomach is joined with the jejunum and bypasses the duodenum. Thus the opening of the duodenum must be closed to prevent the digestive contents from escaping into the abdominal cavity.


During the recovery period, the nasogastric tube is left in place to help drain the secretions from the gastrointestinal system until the body is recovered enough to eliminate these secretions normally. Once the normal movement of the digestive tract (peristalsis) is detected, the patient is given very small amounts of fluid. If the intestines can process the ingested fluids, then the nasogastric tube is removed and the amount of fluid ingested is gradually increased. Typically, if there is no pain or nausea and vomiting, the patient can be started on a diet containing small amounts of solid food.




Uses and Complications

The risk of complications is relatively high in a total gastrectomy and lessens if smaller portions of the stomach are removed. The overall rate of complications is approximately 10 percent.


Since the stomach has such an important role in the process of digestion, it is not surprising that complications and adverse effects occur postsurgically. Some of the most common symptoms noted after gastrectomy include a feeling of discomfort and fullness after ingesting a relatively small meal. This feeling is attributable to the fact that the stomach volume has been reduced in a partial gastrectomy or eliminated in a total gastrectomy. New ulcers may also form and necessitate further drug treatment. Gastritis (inflammation of the stomach lining) may also occur after surgery, as well as a condition called dumping syndrome
. Patients with dumping syndrome feel weak, nauseated, and light-headed after a meal because the food moves too rapidly out of the stomach. Most of these side effects can be treated with medications and dietary changes.


Long-term complications include malabsorption
problems. Occasionally after gastrectomy, the digestive system cannot compensate adequately for the loss of the stomach, leading to poor digestion and absorption of nutrients. The most common malabsorptive disorder following gastrectomy is the inability to absorb vitamin B12. The stomach produces a substance called intrinsic factor which is required for the absorption of this essential vitamin. Without intrinsic factor and the ability to absorb vitamin B12, the patient must receive monthly injections of the vitamin for the rest of his or her life.




Perspective and Prospects

Early detection of stomach cancers and ulcers may help reduce the need for gastrectomies. Endoscopic examinations in which the physician can observe the lining of the stomach through a surgical tube passed into the patient’s mouth and down the esophagus may aid in the early detection of stomach problems such as cancer and ulcers that are failing to heal.


Aggressive medical management of gastrointestinal ulcers will likely reduce the chance that an ulcer will perforate and require gastrectomy. Antiulcer medications are available to reduce the amount of stomach acid released, to add to the protective barrier of the stomach, and to eradicate the bacteria known to cause many ulcers. Destroying the bacteria, Helicobacter pylori, increases the likelihood of curing the patient of ulcer formation.




Bibliography


Brunicardi, F. Charles, et al., eds. Schwartz’s Principles of Surgery. 9th ed. New York: McGraw-Hill, 2010.



"Gastrectomy." MedlinePlus, December 10, 2012.



Leikin, Jerrold B., and Martin S. Lipsky, eds. American Medical Association Complete Medical Encyclopedia. New York: Random House Reference, 2003.



Mohamed, Habeeb. "Laparoscopic Sleeve Gastrectomy: An Ideal Procedure for Control of Morbid Obesity." World Journal of Laparoscopic Surgery 5, no. 2 (May–August, 2012): 89–101.



McCoy, Krisha. "Gastrectomy." Health Library, November 26, 2012.

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