Antrectomy, also called distal gastrectomy, is a type of gastric resection surgery that involves the removal of the stomach antrum to treat gastric diseases causing the damage, bleeding, or blockage of the stomach. This is performed using either the Billroth I (BI) or Billroth II (BII) reconstruction method. Quite often, antrectomy is used alongside vagotomy to maximise its safety and effectiveness. Modern antrectomies typically have a high success rate and low mortality rate, but the exact numbers depend on the specific conditions being treated.
The history of antrectomy traces back to the 19th century, starting with the first successful gastric resection in 1810. Since then, antrectomy has undergone a magnitude of changes, where development in the field continues to this day. Even though antrectomy paired with vagotomy and anastomosis is now the established gold standard, its side effects and clinical relevance remains a controversial subject. With advancements in alternative surgeries and other non-invasive treatments, antrectomy is less common nowadays.
Purpose Generally, an antrectomy is performed to treat bleeding and blockage of the stomach. This could be caused by a variety of gastric disorders, including: Peptic ulcer disease (PUD): The disease is characterized by ulcers developed either by impaired mucus protection or an excess of gastric acid production. Antrectomy could either lead to the reduction of gastric acid levels or the removal of the peptic ulcer altogether. Antrectomy is rarely warranted in this case since PUD rarely recurs and is usually manageable via medications. Zollinger–Ellison syndrome: The condition features excessive gastric acid production. Antrectomy removes gastrin-producing G-cells in the stomach antrum, in turn reducing gastric acid levels. Gastric cancer: Antrectomy could remove gastric tumors developing in the antrum. Gastric antral vascular ectasia syndrome (GAVE): The disease is characterized by excessive bleeding in the stomach. By removing the bleeding site and reconnecting the upper stomach with the intestines, antrectomy controls chronic bleeding and ensures gastric continuity. Gastric outlet obstruction (GOO): It is a condition where the passage between the stomach and the duodenum is blocked. Removal of the blocked stomach parts by antrectomy could ensure continuity of the gastrointestinal system. Penetrative wounds in the duodenum, stomach, or pancreas: The removal of devitalized tissue by antrectomy could prevent continuous bleeding and inflammation from wound infection.
Diagnosis The diagnosis of stomach disorders begins with the examination of the patient’s history and family history, and supplemented with a physical exam. Old age and recent significant weight loss would suggest the possibility of gastric cancer. A family history of duodenal or gastric ulcers would require the patient to describe the type of discomfort he/she is experiencing. Different stomach disorders manifest pain at different time periods.
The most common diagnostic tests for stomach disorders include endoscopy, double-contrast barium x-ray study of the upper GI tract, and the detection of H. pylori infection.
Surgical procedure A midline epigastric incision is first made from the xiphoid process of the sternum to the umbilicus. The opening can be widened by extending the incision inferiorly. When the abdominal organs are exposed, thorough exploration is undertaken to assess the extent of disease and, in the case of stomach cancer, to confirm resectability.
Two surgical methods can then be used to perform antrectomy: Billroth I (BI) reconstruction method: a gastroduodenostomy with end-to-end or end-to-side surgical anastomosis; the duodenal passage is preserved and remains intact. Billroth II (BII) reconstruction method: a gastrojejunostomy with end-to-side surgical anastomosis.
Billroth I (BI) reconstruction method
With end-to-end surgical anastomosis The gastrocolic ligament of the greater omentum is incised at the middle of the greater curvature of the stomach, which opens the lesser sac. The dissection for gastric ulcers can be done between the gastroepiploic vessels and the gastric wall. In carcinoma, the greater omentum corresponding to the extent of the resection of the greater curvature must be removed at the same time. The incision continues along the greater curvature towards the duodenum. Near the pylorus of the stomach, the greater omentum becomes thick and divides into the front and back layer. Dissection should be continued bluntly and the right gastroepiploic vessels running between the two layers are ligated.
The Kocher manoeuver is used at a position above or just below the descending (second) part of the duodenum from a lateral direction. The duodenum is mobilised to achieve a good general exposure, which facilitates the subsequent gastroduodenostomy. The preparation of the free superior (first) part of the duodenum is then continued. By stretching the stomach, the dissection proceeds along the greater curvature toward the left medial duodenal wall, then toward the back wall, and finally toward the lateral duodenal wall of the superior part as far as the beginning of the hepatoduodenal ligament. This way, 3 to 5 cm of the back wall of the duodenum can be exposed.
Dissection is then performed along the lesser curvature of the stomach. The right gastric artery is divided between clamps and ligated. The front and back layer of the lesser (gastrohepatic) omentum is severed individually.
The actual resection starts with the cutting of the duodenum between holding or guy sutures. The duodenum is temporarily closed with a sponge; the resection borders of the stomach are then determined.
A sewing instrument facilitates the final step of stomach removal. The incision follows at an angle of 45 degrees to the lesser curvature. The staple line can, but need not, be oversewn. After removal of the distal portion (including the antrum and the pylorus) of the stomach, a clamp is fitted at right angles to the greater curvature. The clamp is pushed far enough orally (towards the mouth) for the removal level to correspond in size to the duodenal lumen. The remaining aboral (away from the mouth) end is cut off after stay sutures are placed at each cut edge. The anastomosis should be performed without clamps.
The end-to-end gastroduodenostomy is accomplished by anastomosing the duodenum to the end of the greater curvature. For this purpose, the two cut surfaces are placed adjacent to each other and two corner stitches are placed, starting at the stomach through the seromuscular layers with tangential grasping of the mucosa. At the duodenum, this stitch is done from inside to outside. The corner suture at the lesser curvature is tied, whereas the suture on the opposite side is left open. The back wall is reconstructed by interrupted back stitches. These stitches start through all layers of the back wall at the cut edge of the lesser curvature from inside to outside and go through all layers of the posterior wall of the duodenum from outside to inside. The suture is led back grasping only the mucosa, first of the duodenum and then of the stomach. Knotting these sutures leads to an exact coaptation, especially at the level of the mucosa. The front wall is best closed with one row of interrupted sutures through all layers with tangential stitches of the mucosa with the same technique as the corner stitches. Special attention must be paid to the Jammerecke (angle of sorrow) on the lesser curvature.
Finally, the anastomosis is checked for patency with the thumb and index finger. The position of the stomach tube is also checked to ensure it crosses the anastomosis. A double-lumen gastric tube is placed across the anastomosis for 2 to 3 days, allowing early enteral nutrition via the distal lumen.
With end-to-side surgical anastomosis In difficult duodenal ulcers, it can be impossible to preserve enough duodenal wall to be able to construct a tension-free anastomosis. In this situation, it is safer to staple close the duodenum and reconstruct the intestinal passage by end-to-side anastomosis. For this purpose, the stomach is removed as previously described; the dissected stomach lumen is then anastomosed onto the front wall of the duodenum.
Usually, an oblique incision should be made on the duodenal front wall so that the incision level starts from oral–medial and goes to aboral–lateral. The suturing technique is the same as for the end-to-side anastomosis. In technically difficult duodenal stump closures, additional coverage of the stump with the back wall of the stomach can be obtained.
Billroth II (BII) reconstruction method Both the left gastric and left gastroepiploic artery are preserved in this method, although the resection is more extended.
At the oral margin of the dissection line, usually covering two-thirds of the stomach, the resection is completed by transverse application of a linear stapler in a way that the complete stomach is divided between one stapler application. The staple line can be oversewn.
The first or second loop of the jejunum is then mobilised and placed tension-free and in a retrocolonic fashion opposite the greater curvature of the remaining stomach. The loop should be long enough and should have a Braun jejunojejunostomy between the ascending and the descending loop.
The last 4 to 5 cm of the stapler line towards the greater curvature should be excised with the help of an electrocautery device in order to form a slim opening for the subsequent gastrojejunostomy. Stay sutures are placed on both sides of the anastomosis. The jejunum is incised with the electrocautery device opposite the mesentery.
The gastrojejunostomy is performed by single interrupted sutures with resorbable suture material and, as the anastomosis cannot be turned, the back wall is sutured by interrupted mattress sutures and the front wall by extramucosal interrupted sutures. Alternatively, continuous suturing with a monofilament resorbable thread on both sides of the anastomosis is possible. Before finalisation of the front wall, a double-lumen gastric tube is placed distally to the anastomosis, allowing early enteral nutrition. In order to prevent enterogastric (bile) reflux, the formation of a jejunojejunostomosis (Braun anastomosis), side-to-side, and 30 cm aborally of the gastrojejunostomy is mandatory. This anastomosis can be either hand-sewn (interrupted or continuous technique, resorbable suture material) or stapled.
Supplementary operations Supplementary operations can be applied alongside antrectomy to maximise its success and effectiveness. One commonly performed is vagotomy (the removal of the vagus nerve), since the vagus nerve also plays a key role in gastric juice regulation. While performed separately, vagotomy and antrectomy reduce stomach acid secretion by up to 60%. Combining both practices could reduce stomach acid secretion by up to 80% through an additive effect. In some cases, antrectomy can be used alongside laparoscopic sleeve gastrectomy to facilitate weight loss. Yet, the clinical relevance of including antrectomy in this procedure remains to be seen.
Outcome The success rate of antrectomy is dependent on the rationale of the surgery. For example, antrectomies that are done to overcome peptic ulcer disease (PUD) have a 95% success rate, while the percentage is higher for gastric antral vascular ectasia syndrome (GAVE). However, antrectomies that deal with gastric cancer or penetrative wounds are not as successful. One possible explanation is that these symptoms are usually more severe and therefore harder to treat, no matter the kinds of surgery used.