clavien_atlas_of_upper_gastrointestinal_and_hepato-pancreato-biliary_surgery2007-10-01_3540200045_springer

In patients with a dilated pancreatic duct or stenosis, the main pancreatic duct is incised longitudinally on its anterior surface extending toward the tail. In these patients, a side- to-side anastomosis is made between the jejunum and the longitudinally incised pancreas, similar to the Partington-Rochelle procedure (see page 758-761).

Postoperative Management

■Postoperative monitoring in an intensive care unit is only rarely required and is based on non-pancreatic co-morbidities

■Close monitoring of vital signs, fluid balance, and serum glucose concentrations

■Temporary nasogastric decompression

■No somatostatin analogue is recommended

Local Postoperative Complications

■Short term:

–Pancreatic leak: ascites, fistula, local collection

–Bile leak (uncommon)

–Obstructive jaundice (e.g., due to operative injury to the common bile duct or perioperative inflammation and edema) (uncommon)

–Jejunal leak

–Intra-abdominal bleeding

–Pancreatic leak:

–Total parenteral nutrition and bowel rest; most leaks close spontaneously

–CT-guided percutaneous drainage for fluid collections

–If the patient is septic, reoperation may be indicated

■Long term:

–Pseudocyst

–Biliary stricture

–Recurrence of pain

–Pancreatic exocrine and/or exocrine insufficiency

The Frey Procedure

■Don’t try to “talk” the patient into an operation:

–Explain the magnitude of the operation in detail and all longand short-term complications, including failure to relieve pain.

–Explain the natural history of chronic pancreatitis including the likelihood of endocrine or exocrine pancreatic insufficiency in the future.

■Technical:

–Open the duct of Wirsung in the head of the pancreas down to the ampulla, creating a road map of the duct before resecting parenchyma; when the duct is impacted with calculi, a small bone curette, stone forceps, or right angle clamp may be helpful in removing calculi.

–In patients with CBD obstruction, one must free up inflamed fibrotic tissue obstructing the duct; a groove can often be felt posteriorly in the location where the CBD traverses the pancreas. To avoid injury to the CBD, a Bakes dilator is placed into the CBD through a cystic or common bile ductotomy. The dilator within the duct is palpated between the index finger behind and the thumb in front of CBD through the surrounding inflamed, fibrotic tissue as the duct is freed up.

–Due to inflammation and edema, sometimes it may be impossible to distinguish the exact margin between the duodenal wall and the pancreas when suturing the Roux-en-Y jejunal limb to the cored out pancreas. We have encountered no adverse effects aside from including some duodenal wall with pancreatic sutures.

■Patient follow-up: continue to follow patients yourself postoperatively; patients look to you (the surgeon) for physical and emotional support rather than to the gastroenterologist or primary care physician.

The Beger Procedure

■Tunneling of the pancreatic head along the portal vein groove starts with the preparation of the superior mesenteric vein on the caudal border of the pancreatic neck. Blunt dissection begins in front and along the mesenteric aspect of the portal vein toward the cranial border of the pancreatic neck. To facilitate this step a suture at this level in the lower border of the pancreas allows lifting the pancreatic neck segment anteriorly. If severe bleeding should occur, compression of the pancreas towards the spinal column interrupts the blood flow from the splenic vein. Transection of the head anterior to the portal vein exposes the portal vein for repair of the vessel wall.

■Placing a hand behind the head of the pancreas when the subtotal excision of the pancreatic head is to be performed helps to minimize blood loss.

■If the intrapancreatic wall of the common bile duct is not palpable or visible, a KehrSonde or a biliary Fogarty® catheter can be passed via a choledochotomy or preferably through the cystic duct to help palpate the intrapancreatic common bile duct.

■Frozen section of the inflammatory mass is necessary, because about 5% of patients with an inflammatory mass have pancreatic cancer.

■Accidental incision of the intrapancreatic wall of the common bile duct need not be sutured; this part can be included into the anastomosis between the shell of the pancreatic head remnant and the jejunal loop (side-to-side anastomosis).

■If there is marked stenosis of the intrapancreatic common bile duct, an additional biliary anastomosis is necessary. A single layer anastomosis between the jejunal loop and the common bile duct using absorbable suture material should suffice.

Exploration of the Gastrinoma Triangle

Jeffrey A. Norton

Introduction

Gastrin-secreting neoplasms were first described by Zollinger and Ellison in 1955. These unusual neoplasms can be either benign or malignant. The diagnosis of the Zollinger-Ellison syndrome depends on an increased fasting serum gastrin concentration (>100pg/ml), increased basal acid output (>10mEq/l), and an abnormal secretin test (increase of >200pg/ml in serum gastrin concentration after 2U/kg of intravenous secretin). While originally believed to be primarily neoplasms of the pancreas, today we know that most “curable” gastrinomas arise in the wall of the proximal duodenum.

Gastrinomas can occur as sporadic (non-familial) neoplasms or as one of the manifestations of multiple endocrine neoplasia-1 syndrome (MEN-1); MEN-1 includes neoplasms of the pituitary and parathyroids, neuroendocrine neoplasms of the duodenum and pancreas, and carcinoid neoplasms of the foregut and midgut.

Indications and Contraindications

misses the small duodenal gastrinomas.

– Endoscopic ultrasonography can detect small tumors within the pancreas, but may miss duodenal gastrinomas.

The gastrinoma triangle is defined as the region that includes the head of the pancreas and the duodenum in which over 85% of gastrinomas arise.

Most gastrinomas arise in the proximal duodenum, especially the occult neoplasms, but gastrinomas also occur in the pancreatic head, especially in association with the multiple endocrine neoplasia (MEN) syndrome.

Several “primary” lymph node gastrinomas have been reported to occur within the gastrinoma triangle with long-term cure after lymphadenectomy alone.

Sporadic gastrinomas are usually solitary and often (~50%) metastatic to lymph nodes.

In the familial MEN-1 setting, gastrinomas are usually multiple within the duodenum and pancreas and can metastasize as well. In all instances, the duodenal gastrinomas are most frequently missed, and thus opening the duodenum for transmural palpation is critical for their operative detection.

Access is best obtained via a bilateral subcostal division of the falciform ligament, and installation of a mechanical retractor (we prefer the Thompson retractor).

Next, the surgeon opens the lesser sac widely by dividing the gastrocolic ligament from the hepatic flexure to the splenic flexure, thereby exposing the entire neck, body, and tail of the pancreas. The tissue along the inferior border of the pancreas is opened to allow the surgeon to palpate tumors within the pancreas between the thumb and forefingers.

The next maneuver involves an extended Kocher maneuver by mobilizing the entire right colon and the proximal as well as the distal duodenum; this allows palpation of the head of the pancreas and, equally important, the wall of the duodenum.

Intraoperative ultrasonography is performed in a systematic fashion with a nearfield, high-resolution transducer. Small neoplasms within the pancreas are identified by their sonolucent nature compared to the more echo-dense pancreas. Although intraoperative ultrasonography of the duodenum is also performed, duodenal gastrinomas, if small, are often missed by this procedure.

Finally, the liver is also evaluated for metastases.

All lymph nodes within the gastrinoma triangle are excised in a systematic fashion for pathologic analysis starting with a lymphadenectomy of the hepatoduodenal ligament. Lymph nodes from the porta hepatis to the duodenum are excised, labeled, and sent for pathologic analysis, as are nodes from both the anterior and posterior border of the head of the pancreas.

Neuroendocrine neoplasms identified within the head of the pancreas are enucleated with palpation or via ultrasonographic control. When a tumor is enucleated from the head of the pancreas, 5ml of fibrin glue is applied to the site of enucleation, and a closed suction drain is placed nearby.

If the location of the tumor is not known, a duodenotomy is essential, because duodenal gastrinomas often may only become detectable by this method. The surgeon can palpate the tumor within the wall of the duodenum between the index finger within the duodenal lumen and the thumb on the serosal side.

If the duodenal tumor has been identified, the duodenal incision used to remove the duodenal gastrinoma can be used to explore the remainder of the duodenum.

Because the neoplasm arises from the submucosa and can invade the mucosa, the gastrinoma should be excised via a full thickness specimen with a rim of normal duodenal wall around the tumor. In patients with MEN-1, multiple duodenal neoplasms may be present, and the surgeon must carefully palpate and inspect the remainder of the inner surface of the duodenum after it is open to exclude the presence of other neoplasms. Do not confuse the ampulla of Vater or the entrace of the minor pancreatic duct with a gastrinoma. After excising a duodenal gastrinoma, the duodenum is closed with a single-layer, full-thickness, monofilament absorbable suture in a transverse direction so as not to narrow the lumen. If a long duodenotomy is necessary, a longitudinal closure is performed. A periduodenal or peripancreatic closed suction drain is left.

Postoperative Tests

■The patient is kept on the same dose of proton pump inhibitor postoperatively for 1–3months as the preoperative dose; parietal cell hypertrophy as occurs with Zollinger-Ellison syndrome may take approximately 3–6months to involute.

■A postoperative fasting serum gastrin measurement should be compared to the preoperative level. For selected patients, fasting serum gastrin, basal acid output, and secretin stimulated gastrin are not done 3–6months postoperatively.

■On occasion, we often obtain a CT with oral contrast on postoperative day 5 to rule out a duodenal leak and a peripancreatic fluid collection.

■The drain is removed when the patient is eating a regular diet, drainage fluid is low in amylase activity, and the volume is less than 20ml/day for 2 consecutive days. We may discharge the patient with a drain in place to be removed later.

Local Postoperative Complications

■Short term:

–Duodenal leak

–Pancreatic leak and/or abscess

–Pancreatic fistula

–Intra-abdominal bleeding

–Pancreatitis

–Duodenal ulcer bleeding

■Long term:

–Duodenal stricture

–Recurrent hypergastrinemia

■Other manifestations of MEN-1 (hypothalamic, parathyroid, carcinoid)

Tricks of the Senior Surgeon

■Do not cut corners; do the same operation every time regardless of the preoperative localization studies.

■Develop a dedicated team approach; an ultrasonographer willing to take the time and effort to find the gastrinoma is crucial.

■Beware of the ampulla and the pancreatic duct on the medial wall of the duodenum as these can feel like nodules and have been mistaken for a duodenal gastrinoma. I remove the gallbladder and pass a catheter through the cystic duct into the duodenum if there is any question about the location of ampulla. On occasion, I have given secretin intraoperatively to stimulate pancreatic secretion if there is a question that I may be identifying the pancreatic duct orifice.

■Exclude MEN-1 preoperatively by screening for other endocrinopathies and questioning family history.

■Remember that patients with both Zollinger-Ellison syndrome and MEN-1 generally have multiple pancreatic and duodenal neuroendocrine neoplasms, and thus cure-rate is very low. If a patient also has primary hyperparathyroidism, do the parathyroid operation first as this may ameliorate the manifestations of Zollinger-Ellison syndrome.

■Be sure to continue the patient on an aggressive pharmacologic acid suppressive medication during the perioperative and postoperative period.