Steps Of Subtotal Gastrectomy
Magdalen Dano
Patients with a malignancy in whom partial gastrectomy is planned can undergo a staging laparoscopy to assess the extent of the tumor and metastasis. Laparoscopy may detect peritoneal dissemination or liver metastasis that was not detected by conventional methods of imaging and other modalities. It is a safe and effective method of staging that can be helpful in avoiding nontherapeutic explorations and providing a guideline for appropriate treatment planning.
An upper midline incision from the xiphoid process to the umbilicus with an optional extension inferior to the umbilicus provides quick and bloodless access to the abdomen. Another option is a chevron or rooftop incision. This, combined with self-retaining subcostal retractors, provides excellent access to the upper abdomen.
Further elements of the procedure depend on the choice of reconstruction. After resection of the stomach, continuity can be achieved with a gastroduodenal anastomosis (Billroth I). A tension-free gastroduodenal anastomosis requires good duodenal mobilization.
The second option is to close the duodenal end and to perform a gastrojejunal anastomosis (Billroth II or its modifications). Several techniques have been described for the gastrojejunal anastomosis, and a description of each technique is beyond the scope of this topic. Two main variations to the gastrojejunal anastomosis include an end-to-side gastrojejunostomy using an uninterrupted loop of jejunum and an end-to-side gastrojejunostomy to a Roux loop.
Gastroduodenal anastomosis, when possible, is preferred because it maintains the physiologic route of gastric emptying. However, it is not technically feasible if a more extensive gastric resection is necessary or if duodenal mobilization is difficult owing to inflammation or adhesions, in which cases a gastrojejunal anastomosis is recommended.
If the intention is to perform a gastroduodenal anastomosis, the first step is duodenal mobilization. The duodenum is mobilized by incising the peritoneum along its lateral border and then reflecting the duodenum to the left side until the inferior vena cava is exposed. This process is also referred to as kocherization. Care should be taken to avoid injury to the structures in the lesser omentum and middle colic vessels while mobilizing the duodenum.
The greater omentum is freed from the transverse colon by dividing along the avascular plane between the transverse colon and the anterior leaf of the omentum. It is easier to identify an avascular window along the left half of the transverse colon. Further division of the omental reflection is extended toward the right side.
This step carries the potential of inadvertent injury to the middle colic artery. Such an injury can be avoided by spreading the gastrocolic omentum along the greater curvature to clearly visualize and demonstrate the vascular pattern of the gastroepiploic vessels and lifting the transverse colon intermittently to clearly visualize the vascular pattern of the transverse colon. As the lesser sac is entered, the posterior wall of the stomach is visible.
The posterior wall of the stomach is freed by dividing gastropancreatic folds of peritoneum. The lesser omentum is separated from the undersurface of the liver for malignancy and along the lesser curvature for ulcer disease.
The right gastric artery is identified at the inferior end of the lesser curvature as originating from the proximal hepatic artery or the gastroduodenal artery. This is doubly ligated and divided. Similarly, the gastroepiploic artery is identified close to the inferior end of the greater curvature, doubly ligated, and divided.
At this point, about 1-2 cm of duodenum adjacent to the pylorus is cleared of all fat and vascular adhesions. Care is taken to avoid injury to the pancreatic tissue while clearing the duodenum. The duodenum is divided by a linear cutter or linear stapler at this level (see the image below).
The greater curvature of the stomach is mobilized further by dividing the gastrosplenic ligament. Depending on the extent of the planned gastrectomy, the greater curvature is mobilized to the point where the gastroepiploic artery is closest to the gastric wall (hemigastrectomy) or farther proximally to the second short gastric artery (subtotal gastrectomy). The first short gastric artery is left behind to supply the remnant stomach.
Similarly, the point of division of the stomach along the lesser curvature is marked at the level of the third prominent vein (hemigastrectomy) or about 1 cm inferior to the esophagogastric junction (EGJ; subtotal gastrectomy) (see the image below).
The left gastric artery is divided as a part of subtotal gastrectomy. This artery divides into two branches close to the lesser curvature. The left gastric artery is secured via double ligation or ligation followed by a transfixing suture on the arterial side and a tie on the gastric side before being divided.
Resection of adjacent organs (eg, distal pancreas, spleen, colon) is performed for lesions with direct involvement into these structures. Distal pancreatectomy and splenectomy are not performed as part of a conventional D2 lymphadenectomy, owing to increased postoperative morbidity and mortality.
A part of the staple line on the gastric side in the inferior aspect toward the greater curvature is opened up corresponding to the duodenal end diameter. Interrupted delayed absorbable sutures are taken from the middle of the posterior walls of the stomach and the duodenum. After all sutures are placed along the posterior layer, they are tied, starting from the lesser-curvature side. Once secured, the anterior layer is then similarly sutured.
The duodenal stump remains closed. A loop of jejunum is identified close to the duodenojejunal flexure. Care should be taken to keep the afferent loop reasonably short. The loop is anchored along its axis and isoperistaltic to the posterior wall of the stomach with delayed absorbable seromuscular sutures. An opening is made in the jejunum equal to about twice the diameter of the jejunal lumen. The staple line on the stomach is opened to correspond to this length.
The anastomosis is performed with a continuous absorbable suture that starts from the middle of the posterior layer on either side and is continued to meet in the middle of the anterior layer. A fourth layer of seromuscular sutures is placed to bury the anterior continuous suture line (see the image below).
The principles of gastrojejunal anastomosis remain similar for a Roux-en-Y anastomosis. Instead of a conventional Polya complete anastomosis, a Hofmeister-Finsterer modification can be performed, in which the part of the opening in the stomach on the lesser-curvature side is closed and fixed to the jejunum with seromuscular sutures so as to narrow the anastomosis and thus exert a valvular effect. This is more useful in patients who are undergoing stomach resection for benign conditions when the conventional Polya anastomosis may be very wide (see the image below).
A 30-mm linear cutter is applied at the desired level of section over the duodenum. Adequate care is taken to prevent inclusion of any other structures, including mesentery, before firing the stapler. Linear staplers can be similarly used to section the stomach. Because the stomach is fairly wide, it may be necessary to fire the stapler sequentially.
Once divided, a loop of jejunum is anchored to the posterior wall of the stomach with seromuscular stay sutures. The jejunal loop can also be anchored by using Babcock forceps. A small enterotomy on the jejunal side and a small gastrotomy on the gastric side are made to allow insertion of the two limbs of the linear cutter.
Once the device has been inserted, its direction is adjusted so that it is maintained parallel to the axis of the jejunum before being engaged and fired. The device is then removed, and the suture line is visualized through the enterotomy to ensure adequate hemostasis. The gastrotomy and enterotomy can be closed with a suture closure (in one or two layers) or with a linear stapler.
The other method involves partial transection of the stomach with a linear cutter followed by a handsewn anastomosis between the remaining open part of the stomach and the jejunum. In comparison with the aforementioned techniques, the gastrojejunal anastomosis is limited in length (see the images below).
Port placement for laparoscopic gastrectomy involves a 12-mm optical port at the umbilicus, a 5-mm epigastric port for liver retraction, two operating ports, and a right lateral port for gastric retraction. The approach for gastrectomy is similar to the open approach.
Initially, the lesser sac is entered by opening the gastrocolic omentum and the lesser omentum. The greater and lesser curvatures are cleared to the initial 2 cm of the duodenum before a stapler is fired to divide the duodenum. The greater curvature is freed to the point of proximal division, and the left gastric artery is identified and divided after retraction of the stomach superiorly and to the left. The specimen is extracted by extending one or both of the operating port incisions. Gastrojejunostomy is usually performed extracorporeally via the same incision.
A study by Takata et al reported the use of single-incision laparoscopic partial gastrectomy in 12 consecutive patients with gastric submucosal tumors. [22] In this procedure, three trocars were placed in the umbilical incision, and the lesion was mobilized and resected with endoscopic staplers. The authors found this approach to be a safe and practical alternative to conventional multiport laparoscopy in these patients, except for lesions originating in the lesser curvature and close to the cardia/pylorus.
Okumura et al, with the aim of minimizing the volume of resected tissue, developed a laparoscopic partial gastrectomy with seromyotomy (the "lift-and-cut" method) for gastric gastrointestinal stromal tumors (GISTs) and evaluated it in 28 patients. [23] They reported an average operating time of 126 minutes (range, 65-302), an average blood loss of 10 mL (range, 0-200), and a median hospital stay of 7 days (range, 5-21). There were no intraoperative complications and no postoperative complications of Clavien-Dindo grade II or higher. At discharge, all 28 patients had a sufficient solid diet. No recurrence was reported at a median follow-up of 26.6 months (range, 6-54).
93ddb68554