Atlas of General Surgical Techniques (Courtney M. Townsend Jr., B. Mark Evers)

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3. CLOSING

The abdomen and skin are closed in the usual fashion. The drains are placed to closed bulb suction.

STEP 4: POSTOPERATIVE CARE

Monitor blood glucose and urine glucose.

Monitor amylase and lipase levels to detect postoperative pancreatitis.

Monitor platelet count to detect postoperative thrombocytosis.

One may consider keeping a nasogastric tube in place after this procedure. There has traditionally been a concern that a dilated stomach may undermine the sutures along the short gastric vessels. More recent practice has endorsed very brief use of such tubes.

Monitor the drain outputs, and particularly examine them for amylase levels beginning on day 4 or after a regular diet has been resumed to detect pancreatic fistula.

STEP 5: PEARLS AND PITFALLS

It is important to recognize that all significant vascular inflow to the spleen comes along the splenic artery. For that reason, early isolation of the splenic artery may well maintain control in the event that significant hemorrhage occurs during the attempted resection. Particularly with postinflammatory changes, the dissection along the spleen and the tail of the pancreas may be fraught with potential hemorrhage, and much of this can be prevented by taking early control of the splenic artery.

Although we do not currently recommend additional measures preoperatively, one should be prepared for the possibility of pancreatic fistula, and we therefore take very seriously the ligation of the divided main pancreatic duct in the pancreatic remnant. We particularly make an effort to have good tissue apposition by the closure of our body of the pancreas. It is also quite important to remove the drains after this operation only when one is certain that they have been functioning and that they no longer have any significant output. It is unfortunately well known that one may remove a drain because he or she believes the drain outputs have ceased when they have simply stopped because of drain failure. In this event, one may require interventional radiology to help with proper drainage.

SELECTED REFERENCES

1.Blumgart LH, Belghiti J: Liver resection for benign disease and for liver and biliary tumors. In Blumgart LH (ed): Surgery of the Liver, Biliary Tract and Pancreas, 4th ed. Philadelphia: Saunders, 2007, pp 1341-1388.

2. Sugiyama M, Suzuki Y, Abe N, et al. Modified liver hanging maneuver with extraparenchymal isolation of the middle hepatic vein in left hepatectomy. J Hepatobiliary Pancreat Surg 2009;16:156-159.

3. Shirabe K, Shimada M, Gion T, et al. Postoperative liver failure after major hepatic resection for hepatocellular carcinoma in the modern era with special reference to remnant liver volume. J Am Coll Surg 1999;188:304-309.

C H A P T E R 48

BEGER AND FREY PROCEDURES

William H. Nealon

STEP 1: SURGICAL ANATOMY

All pancreatic surgery requires an understanding of the anatomic relationships in the lesser sac. After either an upper midline or a bilateral subcostal (chevron) incision, one enters the lesser sac by dissecting along the avascular plane at the points of attachment of the gastrocolic omentum to the transverse colon. The proper plane is between the anterior and posterior leaflets. This is my favored point of entry. The alternative entry is by dividing and ligating, in a transverse direction, the vascular structures embedded in the omentum while preserving the gastroepiploic vessels located along the greater curvature of the stomach.

Upon entering the lesser sac, one will encounter varying amounts of inflammatory adhesions between the posterior wall of the stomach and the anterior surface of the pancreas. Considerable dense adhesions may be encountered in the background of chronic pancreatitis.

The pancreas is essentially encased in a sandwich of major blood vessels. The vena cava and aorta occupy the posterior surface in the midline. The splenic artery courses along the superior surface from the aorta toward the tail. The splenic vein occupies the posterior superior surface of the body and tail of the pancreas. It meets the superior mesenteric vein, which is oriented vertically in the groove created by the uncinate process in the posterior aspect of the head of the pancreas and the right lateral and anterior components of the head. The confluence of these two veins constitutes the portal vein, which traverses the uncinate groove encased by the head of the pancreas and emerges to join the bile duct and the hepatic artery in the hepatoduodenal ligament.

The superior mesenteric artery is located in a plane posterior and slightly medial to the superior mesenteric vein. The common hepatic artery, a branch of the celiac trunk (along with the splenic artery and left gastric artery), courses along the superior border of the head of the pancreas to join the hepatoduodenal ligament. Its first branch is the typically miniscule right gastric artery. Just distal is the more substantial gastroduodenal artery, which emerges at a right angle to the hepatic artery from its inferior surface and courses beneath the pylorus, and after sending the right gastroepiploic artery in the plane between the inferior aspect of the pylorus and the superior surface of the head of the pancreas, the gastroduodenal artery pierces the head of the pancreas.

The anterior superior and the posterior superior pancreaticoduodenal arteries also arise from branches of the gastroduodenal artery. These arteries form an arch medial to the C-loop of the duodenum, and they collateralize with branches of the anterior and posterior inferior

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pancreaticoduodenal arteries, which are branches of the superior mesenteric artery. Small branches from these arteries provide blood supply to the duodenum. Both the Beger and Frey procedures include division of these anterior vessels. Preservation of the posterior arcade ensures viability of the duodenum.

Key anatomic features in pancreatic head resections and in the Beger and Frey procedures are the network of tributaries projecting between the superior mesenteric vein/portal vein confluence and the uncinate process. These tributaries are located at the right lateral aspect of the veins. These tiny veins exit the pancreas at the mid-portion of the groove in which the major veins reside.

The pancreas is entirely retroperitoneal, and therefore operative procedures will require mobilization of the pancreas from its retroperitoneal position. The plane lateral to the C-loop of the duodenum is incised in nearly all procedures; this plane is avascular, and its mobilization is termed the Kocher maneuver. This exposes the vena cava and aorta, and it permits “bimanual palpation” of the head of the pancreas. The dissection may be easily extended to the fourth portion of the duodenum and the ligament of Treitz (see Figure 48-3).

The inferior border of the body of the pancreas is also avascular, although the inferior mesenteric vein may be encountered to the right of the spine.

Peritoneum overlies the hepatoduodenal ligament. Dissection reveals the triad in gross anatomic terms, which corresponds to the microscopic portal triad—with portal venous, hepatic arterial, and biliary structures. The common bile duct is located in an anterior lateral position, and the hepatic artery is anterior medial. The portal vein is positioned in the posterior groove created by the apposition of these anterior structures (see Figure 48-5).

On the inferior border of the pancreatic head, just where the duodenum dives beneath the superior mesenteric vein and artery, one may dissect the peritoneum and visualize the superior mesenteric vein as it passes superiorly beneath the head of the pancreas.

The main pancreatic duct originates in the tail of the pancreas and traverses the length of the pancreas to exit in the duodenum through both main ampulla (Vater) and the accessory ampulla, which is located more proximally in the duodenum. The main pancreatic duct (Wirsung) and the minor or accessory duct (Santorini) fuse during fetal development at what is termed the genu or “knee” of the duct.

INDICATIONS

The indication for surgery in all patients with chronic pancreatitis is essentially the same. The most common indication for surgery is chronic unremitting abdominal pain.

A second indication for surgery in chronic pancreatitis is episodes of recurrent, acute exacerbations, either alone or combined with constant pain.

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Some element of biliary stricture results either in jaundice, which is rare, or in some element of bile duct dilation. This can be confirmed by extremely high circulating levels of alkaline phosphatase in the blood.

Poor nutrition and inability to adequately process nutrients because of exocrine or endocrine insufficiency, as well as the pain associated with eating, is an additional indication for surgery.

STEP 2: PREOPERATIVE CONSIDERATIONS

It is vital to establish the significance of the pain associated with chronic pancreatitis to be certain that this person’s pain is of sufficient magnitude to warrant major operation.

The patient must be carefully scrutinized for current nutritional status, as well as the proper medical management of either exocrine or endocrine dysfunction, which is often associated with this disease. Surgery should be delayed until nutritional status has been stabilized.

Some amount of counseling regarding narcotic dependence should be initiated preoperatively in these patients.

Specific discussion should be made regarding the goals of resuming normal activities, stopping ethanol abuse, and resuming employment. It is incumbent upon the pancreatic surgeon to participate in this form of rehabilitation of these patients to ensure satisfactory outcomes for the goals of this operation.

If a patient has finally reached very high narcotic requirements to manage his or her pain preoperatively, the management of the postoperative pain in these patients can be a daunting task. We have found significant improvements when we perform this procedure with an epidural catheter in place. We have found that even high doses of intravenous narcotics failed to properly manage the pain in these patients in the postoperative period.

We have experience with improving narcotic effectiveness by placing patients on epidural access some days ahead of surgery and using a pure bupivacaine analgesic. If this can be achieved, the patient may have some freedom of his or her endorphin receptors by the time surgery is undertaken.

We perform bowel preparation and colonic cleansing in all patients preoperatively.

A single dose of preoperative intravenous antibiotic prophylaxis is administered using a second-generation cephalosporin.

STEP 3: OPERATIVE STEPS

1.INCISION

We prefer a midline incision for this procedure. The incision is taken from the xiphoid process to just above the umbilicus. Self-retaining retractors are used to establish exposure

(Figure 48-1).

Incision

FIGURE 48–1

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2. DISSECTION

The gastrocolic omentum is separated from its attachments along the transverse mesocolon in the avascular plane by using electrocautery. We find it easiest to enter this plane beginning well to the left of the spine. After entering the lesser sac, the omentum is dissected free of its attachments to the hepatic flexure of the colon and toward the cecum if necessary. This permits access to the lesser sac, and any adhesions between the posterior wall of the stomach and the anterior surface of the body and head of the pancreas are carefully dissected (Figure 48-2).

Any of the fatty tissues or adhesions overlying the body and head of the pancreas are carefully cleared to visualize the anterior surface of the pancreas. You will see a bundle of fatty tissue inferior to the pylorus. The right gastroepiploic vessels are within this bundle. These should not be divided at this time. Often a branch can be seen traversing between this bundle and vessels on the inferior border of the pancreas. These can be divided safely between clamps.

At this point, the duodenum and the head of the pancreas are mobilized from their posterior attachments in the retroperitoneum by dividing the peritoneum lateral to the C-loop of the duodenum. This dissection is then carried out toward the left beneath the head of the pancreas. The superior vena cava and the aorta can be identified posteriorly during the dissection. After adequate dissection, you may bimanually palpate the head of the pancreas

(Figure 48-3).