Biliary and Portal Venous Interventions

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What are the indications for percutaneous transhepatic biliary drainage?

Percutaneous biliary drainage is indicated for the treatment of cholangitis or pruritus related to hyperbilirubinemia in the setting of benign or malignant obstructive biliary disease. Biliary drainage may also be performed in the setting of a traumatic bile leak to help divert bile and promote healing of the injured duct. Generally, percutaneous drainage is indicated only if access of the ducts via endoscopic retrograde cholangiopancreatography (ERCP) is impossible, since ERCP is associated with a lower major complication rate.

2

List the causes of benign and malignant biliary obstruction.

• Common benign causes include bile duct calculi ( Figure 72-1 ), benign strictures, pancreatitis, and sclerosing cholangitis ( Figure 72-2 ).

  
  

• Less common benign causes include Caroli's disease, Mirizzi syndrome, and parasitic infection.

• Common malignant causes include pancreatic cancer ( Figure 72-3 ), metastatic disease, and cholangiocarcinoma.

  

• Less common malignant causes include gallbladder carcinoma and ampullary tumors.

3

What is the most commonly encountered biliary ductal anatomy?

The left hepatic duct is formed by the union of medial and lateral segment bile ducts. Right hepatic lobe bile duct anatomy is more complex and variable. The posterior-inferior and posterior-superior portions of the right hepatic lobe are drained by the right posterior ducts (also known as the right dorsal caudal ducts). The anterior-inferior and anterior-superior portions of the right hepatic lobe are drained by the right anterior ducts (also known as the right ventral cranial ducts). The right hepatic duct is formed by the union of the right posterior segment duct and right anterior segment duct. The confluence of right and left hepatic ducts forms the common hepatic duct, which is joined by the cystic duct (from the gallbladder) to form the common bile duct. The most common biliary ductal anatomy (in ≈60% of the population) consists of a right posterior segment duct that joins the right anterior segment duct to form the right hepatic duct ( Figure 72-4, A ).

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What are some important normal biliary ductal anatomic variants?

The right posterior segment duct sometimes drains into the left hepatic duct, biliary confluence, or common hepatic duct instead of joining the right anterior segment duct ( Figure 72-4, B ). The cystic duct may parallel the common hepatic duct for some distance and have a low insertion with a consequently long common hepatic duct and a short common bile duct, or it may occasionally insert medially as it joins the common hepatic duct. Accessory ducts can be seen in some patients. Sometimes referred to as ducts of Luschka, they are generally small tributaries of the right hepatic ductal system that drain directly from the liver to enter the gallbladder. These accessory ducts have clinical significance, since they can be a source of bile leak and bile peritonitis following cholecystectomy, which may require treatment with biliary stent placement via ERCP or percutaneous transhepatic biliary drain placement.

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Describe the basic steps required to perform diagnostic percutaneous transhepatic cholangiography.

Under fluoroscopic guidance, a 21 G or 22 G needle is passed into the liver through an inferior intercostal or subcostal space at the level of the right midaxillary line. It is important to verify that the needle does not pass through the pleural space. The needle is withdrawn during injection of contrast material in an effort to opacify a bile duct that may have been traversed as a result of the needle pass. When a bile duct is identified, injection of contrast material is continued, and the biliary tree is opacified. A diagnostic cholangiogram is performed with spot fluoroscopic images obtained in anteroposterior and multiple bilateral oblique projections. Ultrasonography (US) may also be used to guide access into the biliary tree, and is especially useful when accessing the left bile ducts.

6

Describe the basic steps required to perform percutaneous transhepatic biliary drainage.

If indicated by the diagnostic percutaneous transhepatic cholangiogram and clinical symptoms, a wire can be placed via the accessing needle into the biliary tree, followed by tract dilation and biliary drainage catheter placement. This is called the “one-stick” method. If the initial puncture was directed into a central duct, a “two-stick” technique may be used. Central duct punctures are not ideal because the risk of injuring a major hepatic vessel is significant. A second needle may be placed into an appropriate more peripheral duct, and the tract is subsequently dilated and used for access. The ideal access site is an opacified peripheral duct that can be easily accessed under fluoroscopic guidance. Aside from a peripheral location, the duct's path should course through an angle that is gentle enough to allow a catheter to be advanced into the small bowel without extreme angulation or kinking. After the second access is obtained, the first needle can be removed. If left-sided biliary drainage is being performed, the needle is passed into the liver from a left subxiphoid approach.

7

What is the difference between an external biliary drainage catheter and an internal/external biliary drainage catheter?

External drains end within the bile ducts above the site of obstruction. The obstructed biliary tree is decompressed by draining the bile externally into a drainage bag. Internal/external drains cross the site of obstruction and end within the small bowel. Bile may drain externally into a drainage bag or internally from the biliary tree through side holes in the catheter into the small bowel. Internal/external drains are advantageous because they can be capped externally to allow for internal drainage to the small bowel only. Internal/external drainage catheters are placed whenever it is possible to cross the site of obstruction because drainage to the bowel is more physiologic than external drainage, and the catheters also are easier to care for. Internal drainage prevents loss of bile salts and electrolytes and allows the bile to aid in fat metabolism within the bowel. It is important to monitor the volume status and electrolytes of patients when draining bile externally. These patients can lose a large volume of fluids rich in electrolytes.

8

When should an internal/external drain be capped? When should this drain be uncapped?

After a de novo biliary drainage, catheters are almost always attached to a bag for gravity drainage for a period of time. External drainage helps to decompress the biliary system. A pressurized system may promote bacterial translocation into the hepatic vasculature, resulting in sepsis. Obstructed systems are likely to be pressurized, and this is exacerbated by the contrast material injected into the ducts during the procedure. Pruritus often resolves more quickly if drainage is maximized. In the setting of a malignant obstruction, administration of chemotherapeutic agents may be delayed if the serum bilirubin level is excessively elevated. In certain situations, internal and external drainage may accelerate normalization of the serum bilirubin level and allow for the subsequent administration of chemotherapeutic agents.

Patients with drains attached to external drainage bags can lose a significant amount of fluids and electrolytes. Tubes are commonly capped when possible to allow for more physiologic drainage of bile. Usually this occurs when concerns over infection have subsided and pruritus has resolved. If chemotherapy is planned, tube capping may be delayed until the serum bilirubin level is within an acceptable range.

After a tube has been capped, it should be uncapped if there is concern for infection (fever, elevated white blood cell count, bacteremia, sepsis), leakage of bile around the catheter, pain, or increasing bilirubin or other liver enzyme levels. After the tube is uncapped, additional tests may be indicated, such as a tube check to determine whether the tube is clogged or malpositioned.

9

A patient begins to leak bile around an indwelling biliary drain. Why does this happen, and what can be done to remedy this?

Biliary drains require considerable maintenance after they are placed, and the maintenance often adversely affects the quality of life of patients. Leakage occurs for various reasons. Standard biliary tubes consist of a catheter with side holes and a distal locking loop. For the tube to work properly, the side holes must be patent and properly positioned. The key to proper positioning is the proper location of the most peripheral side hole. This hole should be located just inside the biliary duct where access was obtained. If the most peripheral side hole of the catheter is malpositioned, leakage can occur. Migration or malposition of the tube so that the hole is outside of the duct and in the parenchymal tract results in bile leaking back along the catheter onto the skin. If the hole is too far in, the bile duct peripheral to the catheter may become obstructed and leak along the course of the catheter. Meticulous tube placement, a cholangiogram that confirms proper positioning, along with good technique in securing the catheter to the skin surface will help to prevent these problems. Another common cause of leakage is clogging of the side holes of the catheter with viscous bile or duct debris. This situation can be managed via catheter exchange with consideration given to upsizing the tube if the complication occurs frequently. As a general rule, long-term biliary drainage catheters are exchanged every 3 months for preventive maintenance.

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