Chapter 29 Gallbladder and Extrahepatic Biliary System
Principles of Surgery Companion Handbook
GALLBLADDER AND EXTRAHEPATIC BILIARY SYSTEM
|Diagnosis of Biliary Tract Disease|
|Cystic Duct Obstruction|
|Biliary Enteric Fistula and Gallstone Ileus|
|Inflammatory and Other Benign Lesions|
|Operations of the Biliary Tract|
Duct System The extrahepatic biliary system begins with the hepatic ducts and ends at the stoma of the common bile duct in the duodenum. The right hepatic and the left hepatic ducts join to form a common hepatic duct that is 34 cm in length. It is then joined at an acute angle by the cystic duct to form the common bile duct. The common bile duct is approximately 811.5 cm in length and 610 mm in diameter. The lower third of the common bile duct curves more to the right behind the head of the pancreas, which it grooves, and enters the duodenum at the hepatopancreatic ampulla (of Vater), where it is frequently joined by the pancreatic duct. The common bile duct and the main pancreatic duct may (1) unite outside the duodenum, (2) unite within the duodenal wall, or (3) exit independently into the duodenum. Separate orifices have been demonstrated in 29 percent of autopsy specimens, and injection into cadavers reveals reflux from the common bile duct into the pancreatic duct in 54 percent. Radiographically, reflux from the common bile duct into the pancreatic duct is present in about 16 percent of persons. The sphincter of Oddi surrounds the common bile duct at the ampulla of Vater. This provides control of the flow of bile and, in some cases, pancreatic juice. An ampullary sphincter that is present in one-third of adults may produce a common channel for the terminal common bile and pancreatic ducts.
Gallbladder The gallbladder is located in the bed of the liver in line with that organ's anatomic division into right and left lobes. It has an average capacity of 50 mL and is divided into four anatomic portions: the fundus, the corpus or body, the infundibulum, and the neck. The fundus is the rounded, blind end that normally extends beyond the liver's margin. It contains most of the smooth muscle of the organ, in contrast to the corpus or body, which is the major storage area and contains most of the elastic tissue. The body tapers into the neck, which is funnel shaped and connects with the cystic duct. The neck usually may be distended into a dilatation known as the infundibulum, or Hartmann's pouch. The lumen is lined with a high columnar epithelium that contains cholesterol and fat globules. The mucus secreted into the gallbladder originates in the tubular alveolar glands in the globular cells of the mucosa lining the infundibulum and neck.
Blood supply to the gallbladder is by the cystic artery, which normally originates from the right hepatic artery behind the cystic duct. It is approximately 2 mm in diameter and courses above the cystic duct for a variable distance until it passes down the peritoneal surface of the gallbladder and branches. Venous return is carried through small veins, which enter directly into the liver, and a large cystic vein, which carries blood back to the right portal vein. Lymph flows directly from the gallbladder to the liver and drains into several nodes along the surface of the portal vein.
The nerves of the gallbladder arise from the celiac plexus and lie along the hepatic artery. Motor nerves are made up of vagus fibers mixed with postganglionic fibers from the celiac ganglion. Sensory supply is provided by fibers in the sympathetic nerves coursing to the celiac plexus through the posterior root ganglion at T8 and T9 on the right side.
The gallbladder is connected with the common duct system via the cystic duct, which joins the common hepatic duct. The segment of the cystic duct adjacent to the gallbladder bears a number of mucosal folds that have been referred to as the valves of Heister. Immediately behind the cystic duct resides the right branch of the hepatic artery. The length of the cystic duct is highly variable, although the average is around 4 cm. Variations of the cystic duct and its point of union with the common hepatic duct are surgically important. It may be extremely long and unite with the hepatic duct at the duodenum, or it may be absent or very short and have a high (cephalad) union with the hepatic duct, in some cases joining the right hepatic duct instead.
The classic description of the extrahepatic biliary passages and their arteries applies in only about one-third of patients. Congenital absence of the gallbladder or duplication is extremely rare. The gallbladder may be found in a variety of anomalous positions. The so-called floating gallbladder occurs when there is an increase in the peritoneal investment with no mesentery. An incomplete mesentery occurs in about 5 percent of patients and predisposes to torsion. The gallbladder also may be left sided or totally intrahepatic. In human beings, the partial or complete intrahepatic gallbladder is associated with an increased incidence of cholelithiasis. Accessory hepatic ducts are present in approximately 15 percent of persons. Large ducts are usually single and drain a portion of the right lobe of the liver, joining the right hepatic duct, common hepatic duct, or infundibulum of the gallbladder. Small ducts (of Luschka) may drain directly from the liver into the body of the gallbladder. When these ducts go unrecognized and are not ligated or clipped at cholecystectomy, an accumulation of bile (biloma) may occur. Anomalies of the hepatic and cystic arteries are present in about 50 percent of persons. A large accessory left hepatic artery originating from the left gastric artery occurs in about 5 percent of persons. In about 20 percent of persons, the right hepatic artery originates from the superior mesenteric artery, and in about 5 percent there are two hepatic arteries, one originating from the common hepatic artery and the other from the superior mesenteric artery. The cystic artery is highly variable, sometimes originating from the left hepatic artery or from the junction of the left or right hepatic arteries with the common hepatic artery, and may be duplicated.
CYSTIC DISEASE OF THE EXTRAHEPATIC BILIARY TRACT (CHOLEDOCHAL CYST)
Congenital cystic abnormalities may occur throughout the entire biliary system. Intrahepatic cystic dilatation is discussed in Chap. 28. Choledochal cysts are discussed in Chap. 37. There are three major varieties: cystic dilatation involving the entire common bile duct and common hepatic duct, with the cystic duct entering the choledochal cyst; a small cyst usually localized to the distal common bile duct; and diffuse fusiform dilatation of the common bile duct.
Bile Formation The normal adult with an intact hepatic circulation and consuming an average diet produces within the liver 2501000 mL of bile per day. This takes place within the hepatocytes and is responsive to neurogenic, humoral, and chemical control. Vagal stimulation increases secretion, whereas splanchnic nerve stimulation results in decreased bile flow. The release of secretin from the duodenum increases bile flow and the production of an alkaline solution by the canaliculi.
Composition of Bile The main constituents of bile are water, electrolytes, bile salts, proteins, lipids, and bile pigments. Sodium, potassium, calcium, and chloride have the same concentration in bile as in extracellular fluid or plasma. The pH of hepatic bile is usually neutral or slightly alkaline and varies with diet. Bile acids, produced endogenously or taken orally, reduce cholesterol synthesis and increase cholesterol absorption from the intestine. The principal bile acids are cholic and deoxycholic acids, and they are synthesized from cholesterol within the liver; they are conjugated there with taurine and glycine and act within the bile as anions that are balanced by sodium. Liver bile also contains mucoproteins, lipoproteins, unesterified cholesterol, lecithin, and neutral fats.The color of the bile secreted by the liver is related to the presence of the pigment bilirubin diglucuronide, which is the metabolic product of the breakdown of hemoglobin and is present in bile in concentrations 100 times greater than in plasma. After this pigment has been acted on by bacteria within the intestine and converted into urobilinogen, a small fraction of the urobilinogen is absorbed and secreted into the bile.
Gallbladder Function During storage, the selective absorption of sodium, chloride, and water results in a concentration of bile salts, bile pigments, and cholesterol that is 10 times higher than in liver bile. Secretion of mucus, approximately at the rate of 20 mL/h, protects the mucosa from the lytic action of bile and facilitates the passage of bile through the cystic duct. This mucus makes up the colorless white bile present in hydrops of the gallbladder resulting from obstruction of the cystic duct.
Motor Activity The passage of bile into the duodenum involves the coordinated contraction of the gallbladder and relaxation of the sphincter of Oddi mainly in response to the ingestion of food and the release of cholecystokinin (CCK) by the duodenum. After the intravenous injection of CCK, the gallbladder is two-thirds evacuated within 30 min. CCK exerts its contractile effects mainly through action directly on the gallbladder smooth muscle cells. The vagus nerve stimulates contraction of the gallbladder, and splanchnic sympathetic stimulation is inhibitory to its motor activity. There is an increased risk of gallbladder disease in patients on prolonged total parenteral nutrition (TPN) perhaps because of the lack of intestinal stimulus and consequent stasis of bile within the organ. During the interdigestive periods, the hormone motilin regulates sphincteric pressure to allow continuous flow of small amounts of bile into the duodenum. Resting sphincteric pressure is around 30 cmH2O. After the ingestion of food, the sphincteric pressure is reduced to 10 cmH2O. The term biliary dyskinesia has been used to describe disturbances of biliary tract motility that occur in the absence of anatomic changes. It has been applied as a primary condition and as a complication of biliary tract surgery often when pain has been noted to occur after the ingestion of fatty foods or on injection of CCK.
Enterohepatic Circulation After the bile enters the duodenum, over 80 percent of the conjugated bile acids are absorbed in the terminal ileum, and the remainder is deconjugated by bacterial activity and absorbed in the colon. Only 5 percent is excreted in the stool.
DIAGNOSIS OF BILIARY TRACT DISEASE
Abdominal ultrasound imaging is the most widely applied diagnostic technique for biliary tract disease in elective and emergent situations. The gallbladder is readily imaged because echo-free bile contrasts with the organ's wall and the liver parenchyma. The intrahepatic and extrahepatic major bile ducts are also defined. Calculi can be demonstrated in more than 95 percent of patients in whom they are present. The discrimination of ductal dilatation has an accuracy of 90 percent. Ultrasonography is the most cost-effective and reliable method for demonstrating gallstones. They appear as reflective foci within the gallbladder or ducts and cast acoustic shadows. Ultrasound imaging also provides diagnostic information for acute and chronic cholecystitis. The characteristic signs include edema and thickening of the gallbladder wall, occasionally gas in the wall, pericholecystic fluid, and absence of visualization of the organ. Ultrasound is the first radiologic step in the evaluation of jaundice because it provides a sensitive method for detecting intrahepatic and extrahepatic ductal dilatation.
Abdominal Radiography Plain x-ray films of the abdomen are of limited value in assessing patients with gallstones or jaundice. They may be useful in excluding other causes of abdominal pain, such as a perforated viscus or a bowel obstruction. Stones are demonstrable on plain film in those 1520 percent of patients with calcium-containing stones. The presence of gas within the biliary tree occurs in patients with a cholecystenteric fistula. Opacification of the gallbladder, or of parts of it, occurs in patients with a porcelain gallbladder. Gas bubbles may be present in the wall of the gallbladder in patients with emphysematous cholecystitis.
Oral Cholecystography This was introduced by Graham and Cole in 1924. This test permits visualization of gallstones and assessement of the absorptive ability of the gallbladder. A radiopaque dye is ingested and absorbed by the gastrointestinal tract and extracted by the liver into the biliary ductular system. Ultimately, if the gallbladder has normal mucosal function, the dye becomes concentrated through the physiologic absorption of water and solutes. A positive study occurs when stones are noted as filling defects in a visualized, opacified gallbladder or when the dye is not adequately concentrated and the gallbladder cannot be visualized. A number of important limitations have reduced its use. False-positive results may occur when patients have been noncompliant or have been unable to ingest the tablets because of nausea and emesis or general medical conditions or when the tablets have not been absorbed through the gastrointestinal tract or have not been excreted into the biliary tract as a result of hepatic dysfunction. Oral cholecystography largely has been replaced by the development and refinement of abdominal ultrasonography.
Computed Tomography (CT) This is inferior to ultrasonography for the detection of stones. The major application of CT is to define the course and status of the extrahepatic biliary tree and adjacent structures. Use of CT is an integral part of the differential diagnosis of obstructive jaundice. Magnetic resonance imaging (MRI) can noninvasively image the biliary tree and is seeing increased application.
Biliary Scintigraphy This provides functional and anatomic information. Technetium 99mlabeled derivatives of iminodiacetic acid (HIDA) are injected intravenously, and they are cleared by the Kupffer's cells in the liver and excreted in the bile. The gallbladder is visualized within 60 min in fasting subjects. The test is particularly applicable when the diagnosis of acute cholecystitis is being considered. Evidence of cystic duct obstruction, as indicated by nonvisualization of the gallbladder, is highly diagnostic. Isotopic visualization of the gallbladder essentially precludes the diagnosis.
Percutaneous Transhepatic Cholangiography (PTC) This uses fluoroscopic guidance to place a small needle into a bile duct. PTC facilitates diagnosis by providing a cholangiogram and permits therapeutic intervention such as intubation of the bile ducts. The technique has little role in the management of patients with uncomplicated gallstone disease, but it has been particularly useful in patients with more complex biliary problems, including strictures and tumors.
Endoscopic Retrograde Cholangiopancreatography (ERCP) This uses a side-viewing endoscope to visualize and intubate the biliary and pancreatic ducts. This test is useful for patients with common bile duct disease (benign and malignant), particularly obstructive jaundice.
Rigid and Flexible Choledochoscopy This visualizes the lumen of the ducts and has been used to determine the presence or absence of calculi. The technique is used as an adjunct to operative cholangiography when the common duct is explored. Choledochoscopy also can aid in the removal of stones and bile duct tumors and in inspecting and obtaining biopsy samples from stenoses.
Injuries of the gallbladder are rare. Penetrating injuries are usually caused by gunshot wounds or stab wounds or during a needle biopsy procedure of the liver. Nonpenetrating injuries are extremely rare. The types of traumatic injuries to the gallbladder include contusion, avulsion, laceration, rupture, and traumatic cholecystitis. Laceration is the most common type of injury following penetrating wounds but also may result from blunt trauma. When infected bile escapes into the peritoneal cavity, a fulminating and often fatal peritonitis results. When bile is sterile, however, it is well tolerated and results in a chemical peritonitis that may be relatively mild. In general, it is preferable to remove the traumatized gallbladder.
Complete transection of the common hepatic duct or the common bile duct (e.g., by a penetrating knife wound) may be treated by debridement and an end-to-end anastomosis over a T tube. With injuries caused by blunt trauma, however, the proximal end of the duct should be anastomosed to a Roux-en-Y limb of jejunum.
The great majority of injuries of the extrahepatic biliary duct system are iatrogenic, occurring in the course of laparoscopic or open cholecystectomy. Some of these injuries are recognized intraoperatively, but the majority become manifest by either increasing obstructive jaundice or profuse and persistent drainage of bile through a fistula postoperatively. ERCP or PTC most clearly defines the site of obstruction or leak.
Injury of the bile duct recognized during surgical operation should be corrected with an immediate reconstructive procedure. Restoration of the continuity of the duct with an end-to-end anastomosis over a T tube may be feasible after a sharp transection, but stricture develops in about half the patients. In most patients, the proximal end of the duct should be anastomosed to a Roux-en-Y of jejunum.
Composition The major elements involved in the formation of gallstones are cholesterol, bile pigment, and calcium. Other constituents include iron, phosphorus, carbonates, proteins, carbohydrates, mucus, and cellular debris. In Western cultures, most stones are made up of the three major elements and have a particularly high content of cholesterol. Pure pigment stones are usually associated with hemolytic jaundice.
Formation Gallstones form as a result of precipitation of bile constituents. Lecithin is the predominant phospholipid in bile, and although it is insoluble in aqueous solutions, it is dissolved by bile salts into micelles. Cholesterol is also insoluble in aqueous solution but becomes soluble when incorporated into the lecithinbile salt micelle. Current theory suggests that there is an equilibrium between the physicochemical phases of these vesicles such that the formation of liquid crystals may or may not result in actual gallstones. When crystals achieve macroscopic size during a period of entrapment in the gallbladder, gallstones form. The basic secretory defect in nonobese patients is decreased bile salt and phospholipid secretion. Chenodeoxycholic acid and ursodeoxycholic acid, which replenish the bile acid pool and reduce cholesterol synthesis and secretion, administered to potential stone formers may return supersaturated bile to its normal composition, preventing stone formation.
The liberal use of ultrasonography has resulted in the diagnosis of calculi in patients without symptoms referable to the biliary tract. In general, patients with asymptomatic gallstones should not be treated. Cholecystectomy for asymptomatic stones may be appropriate for elderly patients with diabetes and for individuals who will be isolated from medical care for an extended period.
Cystic Duct Obstruction
Temporary obstruction to the outflow of bile from the gallbladder is responsible for the most common manifestation of calculous disease, which is biliary colic. This consists of intermittent spasmodic pain in the right upper quadrant, often radiating to the shoulder or scapula, that is precipitated by a fatty or fried meal. The attacks are self-limiting but have a tendency to recur in an unpredictable manner. The treatment is cholecystectomy, preferably by the laparoscopic approach, and it is best performed during that hospitalization but not as an emergent procedure.
Common duct stones may be single or multiple and are found in 412 percent of patients subjected to cholecystectomy. Most common duct calculi are formed within the gallbladder and migrate down the cystic duct into the common bile duct. Less commonly, stones are thought to form within the ducts. Although small stones may pass via the common duct into the duodenum, the distal duct with its narrow lumen (23 mm) and thick wall frequently obstructs their passage. Pain and jaundice may result. Chronic biliary obstruction may cause secondary biliary cirrhosis or infection within the bile duct, giving rise to ascending cholangitis and occasionally extending up to the liver, resulting in hepatic abscesses. Gallstone pancreatitis is generally associated with the presence or passage of common bile duct stones.
The manifestations of calculi within the common duct are variable. Characteristically, the symptom complex consists of colicky pain in the right upper quadrant radiating to the right shoulder with intermittent jaundice accompanied by pale stools and dark urine. Liver function tests demonstrate the pattern of obstructive jaundice, and the alkaline phosphatase level usually becomes elevated earlier and remains abnormal for longer periods than the serum bilirubin level. In patients with ascending cholangitis, Charcot's intermittent fever accompanied by abdominal pain and jaundice is characteristic. The diagnosis may be established by ERCP or PTC. The indications for the removal of common duct stones are (1) their presence as defined preoperatively in a symptomatic patient or by palpation or cholangiographically at the time of operation, (2) a dilated extrahepatic duct, (3) jaundice, (4) recurrent chills and fevers suggestive of cholangitis, and (5) gallstone pancreatitis. Common duct stones can be removed by ERCP, and the performance of an adequate destruction of the sphincter of Oddi will permit stones that were not extracted or which form at a later date to pass into the duodenum without obstruction in the extrahepatic ducts. In a patient undergoing an elective cholecystectomy in whom common duct stones are thought to be present, a preoperative ERCP and sphincterotomy can be followed by laparoscopic cholecystectomy. If common duct stones are detected during laparoscopic cholangiogram, they can be removed by subsequent ERCP or during the procedure by trans-cystic duct retrieval or pushing them into the duodenum. Alternatively, the common duct can be opened, the stones extracted, and a T tube inserted.
If stones are noted to be present when a T-tube cholangiogram is performed postoperatively, several approaches can be entertained. Mechanical extraction of the retained stone can be performed under radiographic control. The T tube is generally left in place for at least 4 weeks after the operation; it is then extracted, and a polyethylene catheter is used to instill radiopaque material into the common duct. A Dormia basket is then advanced through the catheter to entrap the stone. The most commonly used approach is transduodenal papillotomy with extraction of the stone under endoscopic control.
Biliary Enteric Fistula and Gallstone Ileus
A stone in the ampulla of the gallbladder (Hartmann's pouch) can encroach on and erode the common bile duct. This is known as Mirizzi's syndrome. Operative management depends on the extent to which the common duct has been compromised. If there is only a pressure effect, cholecystectomy is sufficient. If the common duct segment is partially or completely destroyed, a reconstructive procedure is mandated and may require a Roux-en-Y limb anastomosis to the proximal normal duct. When biliary enteric fistulas develop, they usually run between the gallbladder and the duodenum, but 15 percent are cholecystocolic fistulas. Mechanical obstruction of the gastrointestinal tract caused by gallstones is a relatively infrequent occurrence. Gallstone ileus causes 12 percent of mechanical small intestine obstructions. It is characteristically a disease of the aged. Typically, intraluminal obstruction is produced by erosion of the stone into the gastrointestinal tract. Almost always the offending calculus enters through a cholecystenteric fistula. Having entered the alimentary tract, the gallstone, which is usually single, may be vomited or passed spontaneously via the rectum. The size of the stone is important, since stones smaller than 23 cm usually pass. When obstruction occurs, the site is usually at the terminal ileum, which is the narrowest portion of the small intestine. When a gallstone blocks the small intestine, the morbid anatomic and physiologic effects of a mechanical obstruction obtain.
A past history suggestive of cholelithiasis or symptoms of acute cholecystitis immediately preceding the onset of gallstone ileus may be present. There is associated cramping, nausea, and vomiting, which may be intermittent. Radiologic examination may be diagnostic if gas is demonstrated within the biliary tract. Biliary enteric fistulas are managed by cholecystectomy and closure by primary repair of the intestinal opening. Definitive therapy consists of locating the stone or stones, enterotomy proximal to the stone, and removal of the offending calculi with closure of the intestine.
INFLAMMATORY AND OTHER BENIGN LESIONS
Acute cholecystitis is usually associated with an obstruction of the neck of the gallbladder or cystic duct caused by stones impacted in Hartmann's pouch. Direct pressure of the calculus on the mucosa results in ischemia, necrosis, and ulceration with swelling, edema, and impairment of venous return. A bacterial cause has been proposed, and positive bile cultures have been noted in 60 percent of patients. Escherchia coli, Klebsiella species, streptococci, Enterobacter aerogenes, Salmonella species, and Clostridium species have all been implicated. Acute cholecystitis in which the gallbladder is devoid of stones is known as acalculous cholecystitis.
Acute cholecystitis can occur at any age, but the greatest incidence is between the fourth and eighth decades. Women are afflicted more than men. Moderate to severe pain is experienced in the right upper quadrant and epigastrium and may radiate to the back in the region of the angle of the scapula or in the interscapular area. The patient is often febrile, and vomiting may be severe. Tenderness, usually along the right costal margin and often associated with rebound tenderness and spasm, is characteristic. The gallbladder may be palpable, or a palpable mass in the region may be the result of omentum wrapped around the gallbladder. The differential diagnosis includes perforation or penetration of peptic ulcer, appendicitis, pancreatitis, hepatitis, myocardial ischemia or infarction, pneumonia, pleurisy, and herpes zoster involving an intercostal nerve.The hemogram usually demonstrates leukocytosis with a shift to the left. Radiographs of the chest and abdomen are indicated to rule out pneumonia. The serum bilirubin level may determine the presence of common duct obstruction. To rule out myocardial ischemia, an electrocardiogram should be performed on any patient over age 45 being considered for surgical treatment. An ultrasonogram may demonstrate calculi and/or a thickened wall of the gallbladder and is the diagnostic procedure of choice. Radionuclide scanning with DISIDA (diisopropyl iminodiacetic acid) or PIPIDA (N-para-isopropyl-acetanilide-iminodiacetic acid) is the most effective diagnostic study in this situation. There have been conflicting opinions on the management of acute cholecystitis, particularly on the optimal time for surgical intervention. Most surgeons now favor early operation, i.e., within 2448 h. In the majority of patients, laparoscopic cholecystectomy is successful.
Emphysematous cholecystitis is a rare form of acute, usually gangrenous cholecystitis associated with the presence of gas in the gallbladder. Pathogenesis is related to acute inflammation of the gallbladder, which often begins aseptically, complicated by a secondary infection with gas-forming bacilli. Cholelithiasis is also present in half the patients, who are frequently diabetic. The diagnosis is usually made on the basis of radiographs that show a globular, gas-filled shadow in the region of the gallbladder, or later, intramural or submucosal gas may appear. The treatment of choice is early operation.
Chronic inflammation of the gallbladder is generally associated with cholelithiasis and consists of round cell infiltration and fibrosis of the wall. Patients generally present with moderate intermittent abdominal pain. Diagnosis is usually established by ultrasonography that demonstrates the presence of stones.
The treatment of chronic cholecystitis and cholelithiasis is cholecystectomy, and the results are usually excellent. Laparoscopic cholecystectomy is the procedure of choice. Acute acalculous cholecystitis frequently is a complication of burns, sepsis, multiple organ-system failure, cardiovascular disease, diabetes, prolonged illness, or a major operation. The DISIDA or PIPIDA scan and ultrasonography are occasionally normal in these patients, but characteristically ultrasonography demonstrates thickening of the wall. Cholecystectomy is the preferred treatment. Infection within the biliary duct system or cholangitis is most frequently associated with choledocholithiasis but also has accompanied choledochal cysts and carcinoma of the bile duct and has followed sphincteroplasty. Clinically, the condition is characterized by intermittent fever, upper abdominal pain, exacerbation of jaundice, pruritus, and at times rigor. Antibiotics usually control the infection, but if the patient's temperature does not fall, surgical drainage should not be delayed. This can be accomplished percutaneously by the transduodenal or transhepatic route or operatively.
Suppurative cholangitis, in which there is gross pus within the biliary tract, constitutes one of the most urgent causes for laparotomy in patients with obstructive jaundice. The condition was first described in 1877 by Charcot, who suggested a diagnostic triad of jaundice, chills and fever, and pain in the right upper quadrant. To these, Reynolds and Dargan added shock and central nervous system depression as specific identifying features of the condition. The disease occurs almost exclusively in patients over 70 years of age. All patients are febrile, and most are jaundiced. Bilirubin, SGOT, and alkaline phosphatase levels are characteristically elevated. Patients have been managed emergently by establishing initial drainage via ERCP or PTC, followed by definitive operation. Surgical treatment is directed at rapid decompression of the duct system and is combined with large doses of antibiotics, particularly those which achieve high levels in the bile.
Sclerosing cholangitis is an uncommon disease that involves all or part of the extrahepatic biliary duct system and often affects the intrahepatic biliary radicals as well. A significant number of cases have been associated with ulcerative colitis, Crohn's disease, Riedel's struma, retroperitoneal fibrosis, and porphyria cutanea tarda. The cause of sclerosing cholangitis is unknown.
Grossly, there is diffuse thickening of the wall of the extrahepatic biliary tract and sometimes of the intrahepatic ducts, with a marked luminal narrowing. The gallbladder is usually not involved. Biopsy examination of the liver may reveal bile stasis or, in long-standing cases, biliary cirrhosis. The histologic evaluation is critical, since it is difficult to differentiate this disease from sclerosing carcinoma of the bile ducts.
The diagnosis is to be considered in patients with a clinical and laboratory picture of extrahepatic jaundice. Jaundice is usually associated with intermittent pain in the right upper quadrant, nausea, vomiting, and occasionally, chills and fever. In long-standing cases with biliary cirrhosis, the manifestations of portal hypertension may appear. The diagnosis is often established by cholangiography. The appropriate management of sclerosing cholangitis remains unclear. No drug therapy has achieved consistent or even usual success. The asymptomatic anicteric patient is not treated. The pruritic and icteric patient is treated for 46 weeks with prednisone; if there is no improvement, or if cholangitis is present or develops, an operation is performed with a preoperative cholangiogram as a guide. If possible, the stenotic segment should be excised and reconstructed with a Roux-en-Y limb of jejunum. Carcinoma must be ruled out by biopsy. In patients with more diffuse or advanced parenchymal disease, hepatic transplantation has become the procedure of choice.
The term papillary stenosis refers to a wide variety of conditions that share a benign abnormality of the sphincter of Oddi. The main symptom of fibrosis or stenosis is abdominal pain, usually colicky and frequently associated with nausea and vomiting. Many patients indicate that they have had previous cholecystectomy without relief of symptoms. The diagnosis generally is made when there is difficulty in passing a No. 3 Bakes dilator through the ampulla of Vater. Transduodenal sphincteroplasty is the preferable treatment.
Carcinoma of the gallbladder accounts for 24 percent of gastrointestinal malignancies. Approximately 90 percent of patients with carcinoma of the gallbladder have cholelithiasis, but the pathogenesis has not been defined. There is also an association with polypoid lesions of the gallbladder. Malignant changes have been noted more frequently in polypoid lesions greater than 10 mm. The calcified porcelain gallbladder is associated with a 20 percent incidence of gallbladder carcinoma. Most tumors are adenocarcinomas. When metastases are present, the liver is involved in two-thirds of patients and the regional lymph nodes in about one-half. Signs and symptoms of carcinoma of the gallbladder are generally indistinguishable from those associated with cholecystitis and cholelithiasis. Half the patients are jaundiced, and two-thirds of those with clinical manifestations have a palpable mass. Ultrasound or CT scanning may suggest the diagnosis. Most long-term survivors are patients who underwent cholecystectomy for cholelithiasis and in whom the malignancy was an incidental finding. Advanced tumors may have a better prognosis if a radical second procedure, which includes lymphadenectomy and partial hepatic resection for lesions located adjacent to the liver, is performed. Large cumulative series report 5-year survival rates of 5 percent.
Bile duct carcinoma is slightly less common than gallbladder cancer. There is no evidence that bile duct stones have a role, and the relationship between the tumors and sclerosing cholangitis remains ill-defined. Approximately two-thirds of the lesions are located in the proximal ducts, often at the confluence of the right and left main hepatic ducts (so-called Klatskin tumors). The tumors are generally small but result in ductal obstruction. Ductal lesions are cholangiocarcinomas of the adenocarcinoma type. The liver and regional lymph nodes are the most frequent sites of metastasis. Characteristically, patients present with the recent onset of obstructive jaundice and pruritus. Patients may have had weight loss, abdominal pain, and cholangitis. The laboratory findings are compatible with the diagnosis of obstructive jaundice. Serum Ca19-9 levels may be elevated. Ultrasonography and CT scanning demonstrate intrahepatic ductal dilatation and distention of the extrahepatic ducts proximal to the point of obstruction. Precise demonstration of the site of obstruction is achieved by cholangiography. Treatment is directed at resecting the tumor, if possible, or palliation by relieving the obstruction. Cure can be achieved only by surgical removal of the lesion, whereas palliation can be effected by operation, radiologic intervention, or endoscopic decompression. Curative resection generally entails removal of the common duct and the common hepatic duct up to and sometimes including the confluence of the right and left hepatic ducts, followed by anastomosis of the proximal dilated system to a Roux-en-Y limb of small intestine. The cure rate remains under 15 percent. If a proximal lesion extends into the liver parenchyma, varying amounts of the liver are removed en bloc. The cure of distal bile duct tumors has been improved by radical lymphadenectomy and pancreaticoduodenectomy (Whipple procedure).
OPERATIONS OF THE BILIARY TRACT
Prophylactic antibiotics are indicated for patients undergoing elective cholecystectomy with specific risk factors such as jaundice, common duct stones, diabetes, and age greater than 65 years.
Cholecystostomy accomplishes decompression and drainage of the distended, hydropic, or purulent gallbladder. It is applicable if the patient's general condition is such that it precludes prolonged anesthesia, since the operation may be performed under local anesthesia. The procedure is principally performed percutaneously with ultrasound guidance.
Cholecystectomy is one of the most commonly performed abdominal procedures. It may be performed laparoscopically or as an open procedure. The gallbladder may be approached through an oblique right upper quadrant or upper midline incision. The cystic duct is identified and a silk ligature passed around it. Dissection is continued craniad, and the cystic artery is identified. The cystic artery should be doubly ligated and transected. The peritoneum overlying the gallbladder is then incised close to the liver, and dissection is begun from the fundus of the gallbladder down to an ultimate pedicle of cystic duct. The cystic duct is transected and ligated 35 mm from the common bile duct.
Laparoscopic cholecystectomy has emerged as the preferred way of treating symptomatic gallstone disease. Trocars are introduced after the instillation of a pneumoperitoneum, and the procedure begins by retracting the gallbladder up over the edge of the liver so as to facilitate exposure of the triangle of Calot. The cystic duct and artery are then identified and divided. The gallbladder is dissected from this area up toward the fundus. The gallbladder is then carefully withdrawn through one of the ports and the pneumoperitoneum released.
Common duct exploration for choledocholithiasis may be indicated when ductal stones have not been removed by preoperative ERCP. After the anterior aspect of the duct has been visualized, a vertical incision is made through the anterior wall. A choledochoscope can be introduced at this time to visualize the lumen and determine whether any stones are present. Ductal stones can be removed by irrigation, balloon-tipped catheters, scoops, or forceps. When the duct is clear of stones, a T tube is inserted into the duct. A completion cholangiogram confirms the absence of stones and the passage of dye into the duodenum. The latter can be facilitated by the injection of glucagon. A postoperative cholangiogram is performed about 1 week postoperatively, and if absence of stones and clear passage of opaque contrast medium into the duodenum are demonstrated, the tube is removed. The common duct can be explored and cleared of stones laparoscopically.
Sphincterotomy or division of the sphincter of Oddi is occasionally indicated for a stone impacted at the ampulla, a stricture, or a functional disorder. A generous Kocher maneuver should be performed initially, followed by a longitudinal anterior duodenotomy. The passage of a Bakes dilator or cathether down the duct facilitates identification of the sphincter, which should be incised at the 11-o'clock position to avoid damaging the pancreatic duct. A pie-shaped segment is removed from the sphincter, and the duodenal and ductal mucosae are coapted with fine absorbable sutures. A T tube may be inserted into the common duct, and the duodenotomy is closed longitudinally.
Choledochoduodenostomy is applicable to elderly patients with multiple common duct stones and a substantially dilated common duct. A Kocher maneuver is performed to relieve any tension on the anastomosis. The distal common duct is incised longitudinally, as is the anterior portion of the duodenum, and a one-layer, large-diameter anastomosis is made.
Most ductal injuries and strictures are preferably repaired with choledochojejunostomy or a hepaticojejunostomy using a 45-cm defunctionalized Roux-en-Y limb of jejunum. Anastomosis should be performed using the antimesenteric side of the jejunum with interrupted absorbable sutures. A stent should be used unless the bile duct is dilated and infection and tumor are demonstrably absent.
For a more detailed discussion, see Schwartz SI: Gallbladder and Extrahepatic Biliary System, chap. 29 in Principles of Surgery, 7th ed.
Copyright © 1998 McGraw-Hill
Seymour I. Schwartz
Principles of Surgery Companion Handbook