- Clinical science
Pancreatic and hepatic surgeries are indicated in the management of malignant/symptomatic benign tumors and traumatic lacerations of these organs. The choice of surgery depends on the location, size, and extent of the malignancy/injury. Depending on the extent of resection, pancreatic surgeries for malignancy include enucleation (for islet cell tumors), partial pancreatic resections (distal pancreatectomy, central pancreatectomy, pancreaticoduodenectomy/Whipple procedure), and total pancreatectomy. Chronic pancreatitis patients with a dilated main pancreatic duct (> 5 mm), not responding to conservative therapy, are candidates for lateral pancreaticojejunostomy with/without resection of the pancreatic head. Complications of pancreatic surgeries include anastomotic leaks, pancreatic ascites/fistula, and exocrine/endocrine insufficiency. Depending on which segments of the liver are removed, hepatic resections include right/left hepatectomy, right/left lobectomy, and segmentectomy. Wedge resections of the liver are performed for small, peripherally located lesions. Other complications of hepatic resections include liver failure, hemorrhage, hemobilia, and bile leaks.
Brief anatomy of the pancreas
- A retroperitoneal organ, which consists of a head, uncinate process, neck, body and tail
- The stomach lies in front of the pancreas, separated from it by the lesser sac/omental bursa.
- The aorta, IVC, splenic vein, portal vein, and left renal vein lie on the posterior surface of the pancreas.
- The splenic artery and superior mesenteric vessels are also in close proximity to the pancreas.
- The main pancreatic duct (duct of Wirsung), which lies within the pancreatic parenchyma, joins the common bile duct to form the Ampulla of Vater, which drains into the 2nd part of the duodenum (major duodenal papilla).
Types of pancreatic surgeries
|Pylorus-preserving pancreaticoduodenectomy (modified Whipple procedure)|| |
|Distal pancreatectomy (with/without splenectomy)|
|Central pancreatectomy|| |
|Total pancreatectomy|| |
|For acute pancreatitis|| |
Debridement of pancreatic parenchyma
Duodenum-preserving pancreatic head resection
Lateral pancreaticojejunostomy + resection of the pancreatic head
|For|| || || |
|For pancreatic fistulae|| |
- Delayed gastric emptying/gastroparesis (most common)
Pancreaticojejunostomy anastomotic leak/pancreatic ductal disruption → leakage of pancreatic secretions into the abdominal cavity
- → Hyperchloremic acidosis
- → Pancreatic fistula
- Hepaticojejunostomy anastomotic leak → biliary peritonitis
- Exocrine pancreatic insufficiency
- Endocrine pancreatic insufficiency (diabetes mellitus) and lifelong dependence on insulin
- Small bowel obstruction: herniation, volvulus, anastomotic stricture
- Intraabdominal abscess or sepsis
- Gastrointestinal hemorrhage
- If the duodenum is resected: iron deficiency anemia
Suspect a pancreaticojejunostomy anastomotic leak in a patient with hyperchloremic acidosis (loss of bicarbonate) and high levels of amylase in abdominal secretions!
Brief anatomy of the liver
- The liver is divided into right and left lobes by the falciform ligament (morphological anatomy). The right and left lobes are different from the right and left halves of the liver which are individually supplied by the right and left branches of the hepatic artery, the portal vein, and the hepatic duct.
- Couinaud's classification of liver segments (functional anatomy):
- The liver is divided into eight functional segments, each with its own branch of the hepatic artery, portal vein, and bile duct.
- Cantlie's line extends from the gall bladder fossa below to the IVC above and contains the middle hepatic vein.
- Segment I (caudate lobe) lies on the posterior aspect of the liver and is uniquely supplied by the right and left branches of the hepatic artery, portal vein, and hepatic duct.
- Left lobe of the liver is composed of segments II, III, IV.
- Right lobe of the liver is composed of segments V, VI, VII, VIII.
General principles of hepatic surgery
- Access: laparotomy (transverse, midline or subcostal incisions) or laparoscopy
- Pringle maneuver: temporary occlusion of the hepatic artery and portal vein by clamping of the free edge of the lesser omentum (hepatoduodenal ligament) in order to control vascular inflow to the liver or to reduce hemorrhage
- Cholecystectomy is routinely performed as part of all major hepatic resections to allow for easier dissection during the surgery.
- Cavitron ultrasonic surgical aspirator (CUSA): uses ultrasonic waves to vaporize only the liver cells while sparing the biliary radicles and blood vessels
Types of liver resections
|Anatomical resections|| |
Right hepatectomy (right hemihepatectomy)
| || |
|Right lobectomy (extended right hepatectomy or right trisegmentectomy)|| |
|Left hepatectomy|| |
|Left lobectomy|| |
|Segmental resection|| |
|Non-anatomical resection||Wedge resection|| || |
- Bile leak
- Liver failure
Before performing extensive hepatic resections the future liver remnant (FLR) needs to be calculated (using CT images), as patients with insufficient FLR postresection, can develop liver failure!