Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3860_Библиотеки_им_академика_М_И_Перельмана

continue to refer patients. Furthermore, many surgeons prefer mapping by PTC before bile duct revision, and if this study discloses biliary obstruction, decompression is mandated.

IV, prior to the procedure, and 1 g every 6 hr for 48 hr in addition to gentamicin 1.5 mg/kg IV, preprocedure fol­lowed by 1.5 mg/kg IV, every 8 hr for 48 hr.

right mid to anterior axillary line over the right upper

quadrant of the abdomen. The exact location is guided by fluoroscopic obser vation of the liver and diaphragm, taking care to choose an approach with minimum risk of a transpleural tract. Fluoroscopic observation of a metal marker at the planned entry site while the patient takes a deep breath is usually enough to accomplish this step. The tract, by necessity, is almost always intercostal. Entry should be over the lower rib rather than under the upper

by filling of tubular lumina with contrast that does not wash away (Fig. 32-10A). In attempting to opacify the biliary tree, the needle tip may traverse or lodge in a portal vein, hepatic vein, hepatic artery, or lymphatic. Each of these nonbiliary lumina has a characteristic ori­entation and appearance that differentiate it from a bile duct, and contrast invariably will wash out of the lumen in all of these nonbiliary structures.

Once a biliary radicle is entered, contrast is injected slowly and gently. Care should be exercised to avoid over­distension of the obstructed biliary tree, which could increase the chance of sepsis. A few milliliters of contrast are injected, followed by aspiration of an equal number of milliliters through the same needle to progressively exchange bile for contrast to visualize as much of the biliary tree as possible. Because iodinated water soluble contrast flows into the most dependent locations, tilting the patient semiupright can be helpful in allowing opaci­fication of the central bile ducts with less overall volume of injected contrast. When sufficient anatomy is appar­ent, diagnostic images are obtained. The definitive drain­age procedure is completed by the originally entered duct, if it is suitable in location and vector or by advanc­ing another needle into a more suitable duct under fluo­roscopic guidance (see Fig 32-10B). A rotating C-arm fluoroscopy unit is most helpful for delineating the three­dimensional array of the biliary system in planning de­finitive access. Coaxial micropuncture access systems are used most often to achieve definitive drainage, either by the initial PTC site or by a different duct (see Fig. 32-10).

were noted in approximately 8% of percutaneous biliary drainage procedures.

11) are amenable to percutaneous transcatheter embolotherapy. Ascites increases the risk of complica­tions, particularly that of intraperitoneal hemorrhage. Without ascites, the close apposition of the hepatic cap­sule to the parietal peritoneum provides a tamponade effect. This advantage is lost when the punctured or lac­erated hepatic capsule is surrounded by fluid. In addi­tion, the presence of ascites between the abdominal wall and the liver renders percutaneous biliary drainage or stent placement more difficult. Guidewires and catheters are more likely to buckle and coil in that space when attempts are made to advance them through the liver parenchyma; use of a sheath can be helpful in this situ­ation. These difficulties are often circumvented by per­forming PBD left biliary drainage from the anterior ap­proach (usually because of gravity there is less ascites anterior) or removing some of the ascites by paracentesis prior to biliary drainage. An internal stent can also be placed via a transjugular, transhepatic approach, thereby avoiding the peritoneal cavity.

stent placement may often succeed when strictures are refractory to endoscopic retrograde advancement of the stent.

(FDA) for use in the biliary system include the Wallstent (Schneider Incorporated), the Gianturco-Rosch Z-stent (Cook Incorporated), and the Palmaz stent (Johnson and Johnson). The Wallstent and Gianturco-Rosch Z­stent are self-expanding (Fig. 32-13). The Palmaz stent requires balloon expansion. In Europe, the Strecker stent is also available, but this stent is not yet approved for use in the United States.

Unlike plastic stents that can be removed and ex­changed transendoscopically or percutaneously, expand­able metal stents are permanent implants. As such, revi­sion of occluded stents consists of balloon dilation of the stent lumen, flushing out inspissated bile, removing tu­mor ingrowth by atherectomy, or deploying a second stent coaxially within the original stent. This second stent can be an internal metallic or plastic stent. Many inter-

ventional radiologists prefer to place internal-external plastic stents through the occluded metal stent from a transhepatic approach. Tumor overgrowth at the end of a stent can be treated by deploying a second stent partly overlapping the first stent.

Most nonmalignant strictures are amenable to surgical repair with good long-term results. Patients whose stric­tures recur after previous operative repair or are not in a favorable anatomic position for surgical repair (e.g., in­trahepatic duct strictures) or patients who decline surgi­cal repair are candidates for balloon dilatation therapy. The long-term success rate for balloon dilatation is not as high as that for surgical repair (40–55% after balloon dilatation versus 88% postsurgical revision, at 3 to 5 years postprocedure).

The first stage of percutaneous balloon dilatation of bili­ary strictures consists of establishing percutaneous biliary drainage and crossing the stricture. Usually, at least 2 days are allowed between initial percutaneous biliary drainage and the first session of biliary balloon dilatation. The patient is kept on broad-spectrum antibiotics started be­fore the initial percutaneous biliary drainage. Balloon size is chosen based on the measured caliber of the adja­cent normal duct. The first balloon dilatation usually is performed using a balloon slightly smaller than the esti­mated normal duct size, with progressively larger balloon diameters used on successive days until a balloon of the established duct size, or perhaps 10 to 20% larger, is used. Typically, a cycle of biliary balloon dilatation involves three different sessions with progressively increasing bal­loon diameters over approximately 1 week’s time. Each balloon inflation lasts approximately 5 min. After com­pletion of a balloon dilatation session, a 10Fr or 12Fr internal–external stent catheter is left across the stricture. In our practice, the stricture is stented for approximately 6 weeks after the final balloon dilatation session. There is a wide variation in the recommended duration of post­procedure stenting, however, ranging from less than a month to 12 to 13 months posttreatment.

Percutaneous cholecystostomy, or percutaneous catheter drainage of the gallbladder, is a safe, minimally invasive interventional procedure that is useful in a number of clinical situations. The most common indication for per­cutaneous cholecystostomy is the treatment of acute cholecystitis in patients who are at high risk for surgical cholecystectomy for reasons of advanced age, cardiac in­stability, severe debilitation, or recent trauma. Percutane­ous cholecystostomy is often used as a temporary measure until the patient becomes medically fit to undergo sur­gery, but it may constitute definitive therapy in patients who are considered to be permanently high surgical risks.

Percutaneous cholecystostomy can serve as a minimally invasive diagnostic as well as a therapeutic maneuver. In the intensive care setting, the diagnosis or exclusion of acute cholecystitis can be difficult. The classic symptom of right upper quadrant pain is frequently masked in trauma victims or otherwise severely ill patients. False-positive radionuclide gallbladder scintigraphy is common when there has been prolonged absence of oral intake. Further­more, such patients may demonstrate sonographic evi­dence of gallstones or bile sludge, but they may not have acute cholecystitis, or they may have acute cholecystitis without gallstones (acalculous cholecystitis). In such confus­ing circumstances, clinical improvement (e.g., defer ves­cence, reversal of shock, reduction in white blood count) within 24 to 48 hrs of percutaneous gallbladder drainage means that the patient almost certainly had acute chole­cystitis. If no clinical improvement occurs after cholecys­tostomy, the gallbladder can be excluded reliably as the source of sepsis.