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Current status of percutaneous transhepatic biliary drainage in palliation of malignant obstructive jaundice: A review
Correspondence Address: Source of Support: None, Conflict of Interest: None DOI: 10.4103/0973-1075.191746
Malignancies leading to obstructive jaundice present too late to perform surgery with a curative intent. Due to inexorably progressing hyperbilirubinemia with its consequent deleterious effects, drainage needs to established even in advanced cases. Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) are widely used palliative procedures each with its own merits and lacunae. With the current state-of-the-art PTBD technique consequent upon procedural and hardware improvement, it is equaling ERCP regarding technical success and complications. In addition, there is a reduction in immediate procedure-related mortality with proven survival benefit. Nonetheless, it is the only imminent lifesaving procedure in cholangitis and sepsis. Keywords: Biliary stenting, Endoscopic retrograde cholangiopancreatography, Obstructive jaundice, Percutaneous transhepatic biliary drainage
Obstructive jaundice can be of benign and malignant etiologies. Of the malignant causes, carcinoma gall bladder, cholangiocarcinoma, pancreatic adenocarcinoma, metastasis, and lymph nodal compression of common bile duct (CBD) constitute the majority of cases. [1] Most of the cases of malignant obstructive jaundice are already advanced and unresectable by the time they are diagnosed, hence carry dismal prognosis with palliation being the only option left. Obstruction needs to be drained even in such cases for alleviation of pain, cholangitis, and pruritus or in certain cases to initiate chemo or intrabiliary brachytherapy. Over the years, palliative care has evolved with the introduction of newer methods and improvisation of existing techniques. Recent palliative measures not only prolong longevity but also improve the quality of life, hence increasing the acceptance to such procedures. [1],[2],[3] Methods of biliary drainage include:
Both ERCP and PTBD are well-established and effective means of biliary drainage for palliation in unresectable cases. With increased technical success rate and expertise in these minimally invasive procedure, recent time has witnessed an exemplary surge in the demand for such procedure over surgical bypass. Selecting an option over other; however, is a multidisciplinary opinion, which not only involves expertise of operator and the site of obstruction but also takes into consideration other factors such as expected survival and the level of postprocedural care provided to the patients. ERCP is usually performed in cases of distal CBD block (beyond hilum) PTBD is preferred in proximal biliary obstruction. [1],[2],[3] Bismuth-Corlette classification [Table 1] is used worldwide for the classification of hilar cholangiocarcinoma, which is based on the status of primary and secondary confluence.
In this review article, authors discuss various intricacies of PTBD including biliary stenting and comparison with other biliary drainage options.
PTBD is an image-guided procedure which can be performed under fluoroscopy or combined ultrasound and fluoroscopic guidance. Its indications are varied including both obstructive as well as nonobstructive etiologies. Indications of PTBD for palliation in obstructive jaundice include:
Elevated serum bilirubin (>3 g/dl) clinically presents as jaundice. Hyperbilirubinemia impedes the initiation/continuation of chemotherapy in certain malignancies. Pruritus is a common accompaniment in malignant obstructive jaundice which may be disproportionate to the jaundice and usually alleviated by the drainage of even a single liver segment. Pain and anorexia further deteriorate the quality of life which may be relieved to some extent by restoring physiological enterohepatic circulation by various drainage means (vide supra). [4],[5],[6],[7]
Selection of appropriate target duct for biliary drainage Prior to the initiation of procedure, three-dimensional cross-sectional imaging, i.e. computed tomography or magnetic resonance imaging of the patient needs to be reviewed to determine the following: PTBD shall be formidable when cross-sectional imaging is not reviewed due to the observed lesser technical success rate of the procedure. [1],[3] The procedure can be performed either via right (subcostal or intercostal) or left ductal (subxiphoid) approach. Selection of appropriate sided duct (right or left) is a personal preference, although there are certain advantages and disadvantages of both [Table 2] and [Table 3]. Reviewing ultrasound prior to biliary puncture is invaluable for assessing the suitability of puncture as well as any contraindication to the procedure [Figure 1].
Left-sided percutaneous transhepatic biliary drainage In case of suitably dilated biliary radicle dilatation, with an 18G puncture needle, under ultrasound guidance, appropriate segmental duct is punctured. In portal triad, biliary radicle is flanked by the branch of hepatic artery and portal vein, caliber of which increases toward the hepatic hilum. Due to this, site of puncture should be as peripheral as possible as more central puncture incurs more risk of major vascular injury [Figure 2].
When the outflow of bile starts, a 0.035 inch hydrophilic guide wire is passed through the puncture needle. Further, the malignant stricture is negotiated with the help of angiographic catheters and hydrophilic guide wires. During the procedure, intermittent check cholangiograms are done whenever needed to map the biliary anatomy, site of obstruction, and position of guide wire and catheters, keeping the contrast volume and concentration to minimum. In cases where the site of biliary obstruction is negotiated, a ring biliary catheter (8.3 Fr) is left on combined external and internal drainage for the initial few days with its tip in the duodenum beyond the ampulla [Figure 3]. After establishment of successful drainage, catheter is capped externally and left solely on internal drainage. In situations when the site of obstruction is not crossed, external drainage catheter is left in the biliary system for its decompression. Further attempts for internalization are done once there is reduction in the degree of biliary dilatation and subsidence of edema (usually after 3-7 days). Internalization is desirable as it restores the physiological enterohepatic circulation, thus preventing the loss of bile salts. Benefits and drawbacks of left-sided PTBD are tabulated below [Table 2].
Right-sided percutaneous transhepatic biliary drainage Initial puncture is fluoroscopically guided, site is below the tenth rib in mid-axillary line (with 10° forward and cranial angulation of needle tip) to obviate pleural injury. Then, under fluoroscopic guidance, puncture needle is advanced for a length of approximately 3-4 cm, following which ultrasound guidance is resorted for further directing the needle to appropriate segmental duct. Remaining steps are similar as mentioned in the left PTBD (vide supra). A comparison of advantages and disadvantages of right-sided PTBD is compared below [Table 3] and [Figure 2]. Postprocedural care Patient should be admitted for a day to look for potential major complications, especially sepsis and hemobilia with continuation of antibiotics [Figure 4].
With increased expertise and better instrumentation, observed technical success rate of PTBD is ~90-95% with fewer complications observed nowadays. These complications can be further reduced by keeping the biliary manipulation to minimum and good antibiotic coverage. [9] Minor Major Pleural effusion, pneumothorax (inadvertent pleural puncture). Catheter dislodgement is more common in external than internal drainage catheters due to better anchorage in the latter. It can be managed by repositioning or probing by a guide wire [Figure 5] through previous catheter's tract. [10]
Pericatheter leak (bile leak along catheter) is a frequently observed complication [Figure 6]a. It can be due to side holes of catheter lying outside the biliary system, catheter kink/block, or ascites. Management in such cases consists of catheter repositioning or upgradation depending on the findings of check cholangiogram.
Cholangitis and biliary sepsis are inevitable complications which can occur despite adequate antibiotic coverage. Although exact etiology is unknown, it can occur due to multitude of factors such as retrograde reflux of intestinal flora during the procedure, ex vitro infection tracking along the drainage catheter, or may be of hematogenous origin. Prophylactically, broad spectrum intravenous antibiotics covering Gram-negative bacteria should be instituted. In addition, during the procedure, manipulations should be kept to minimum coupled with limited use of iodinated contrast during per procedural cholangiography. Symptomatic management should be done in such cases by continuing the antibiotics and maintaining the fluid balance. [1],[10] Hemorrhage/hemobilia after PTBD is usually transient and is less commonly seen with more peripheral biliary radicle puncture [Figure 6]b. As hepatic artery and portal vein also accompany the dilated biliary radicle, side holes of the drainage catheter may get positioned in these vascular structures, which can be corrected by catheter repositioning. [1],[3] Sudden onset or hemobilia occurring 1-2 weeks after the procedure is usually due to arterial injury (active extravasation or pseudoaneurysm), especially if it is pulsatile and there is pericatheter hemorrhage. Angiography needs to be done in such cases followed by embolization of bleeding artery [Figure 7]. [3]
In both proximal and distal biliary obstructions, PTBD complications are similar; however, incidence is higher in cases of proximal (hilar) block due to following reasons
Biliary stenting can be performed endoscopically, percutaneously, or by the combined means. Biliary stents can be either plastic or metallic, selection of which depends on the etiology of biliary obstruction (benign vs. malignant), life expectancy, and affordability. Metallic stents In cases which aim palliation such as unresectable malignancies, self-expandable metallic stents (SEMS) are preferred for permanent stenting over plastic stents due to better patency. If there is occlusion of stent due to tumor ingrowth, then another stent or external/internal drainage catheter can be placed through it without the need of removal . [1],[3],[11],[12] Percutaneous biliary stenting should be contemplated as a staged procedure after initial biliary decompression when there is subsidence of risk of cholangitis/sepsis. After few days (about a week or later) of preliminary decompression, check cholangiogram is done to look for degree of biliary dilatation as well as site of stent placement. In conducive situations, stents are placed into the biliary system covering the tumor. Subsequent to the successful stenting, percutaneous transhepatic drainage catheter is removed, thus alleviating the catheter-related potential complications (vide supra). [1]
As mentioned vide supra that for percutaneous catheter drainage, selection of biliary access (right vs. left) depends on the volume of lobe, status of portal vein and cholangitis. Due to its large volume, usually, the right PTBD is preferred with an intent to salvage the functioning liver parenchyma. However, the right segmental ducts are shorter as compared to the left-sided ducts. As a corollary, further growth of malignancies will lead to proportionately more severe involvement of the right duct. In general, depending on the type of hilar block, the following approach is followed [Table 4] for stent placement. [13],[14]
Types and configuration of metallic biliary stenting Required number and configuration of stents depend on the degree (primary vs. secondary biliary confluence block) of biliary obstruction and the presence of cholangitis [Figure 8].
Configuration of biliary stents Most of the biliary tract malignancies are usually managed by a single stent, especially when primary confluence is patent. However, when there is isolation of right and left segmental ducts, adequate biliary drainage may require bilateral stenting. Biliary stenting contemplated in hilar malignancies (Type IV block) for bilateral biliary drainage can be configured in two ways - "Y and T configuration [Figure 9]. [12],[15]"
Y-shaped It is the most preferred stent configuration in which bilateral (both right- and left-sided) percutaneous biliary access is achieved. The first stent is then placed through one of the access with its proximal and distal tip in the ipsilateral hepatic duct and duodenum, respectively. After this, with the contralateral biliary access, other SEMS is introduced through the mesh of the first one with its positioning remaining same; however, its proximal tip is in the contralateral hepatic duct. This configuration aims to restore the normal biliary anatomy for drainage. T-shaped In this configuration, bilateral stenting can be performed even through the unilateral biliary access. Here, for instance if left PTBD is done, the first SEMS is placed in a horizontal configuration from left to right hepatic duct. The second SEMS is then placed connecting the transverse stent to the CBD in vertical configuration. Although T configuration offers the advantage of bilobar drainage through a single puncture; however, in case of stent block, subsequent re-intervention is comparatively easier in the Y configuration. Plastic stents Plastic stent is preferred in benign causes as it can be retrieved subsequently which is not the option in metallic stents. In certain malignancies such as lymphoma (leading to biliary obstruction) or in hilar block with multiple isolated biliary segments, plastic stenting can be done. [15] Complications of biliary stenting Apart from the possible complications of initial PTBD (mentioned above), specific stent-related adversities may occur which are usually delayed events such as stent occlusion, block, or migration. Stent occlusion occurs due to either tumor ingrowth through its struts or tumor overgrowth either proximal or distal to the stent. Comparing the likelihood of occlusion of plastic and metallic stents, the latter scores with its longer patency rates [Table 5]. [13],[14],[16]
Median patency of the biliary stents depends on its type, i.e., plastic versus metallic, covered or uncovered, its caliber, site of malignant occlusion, and concomitant intraluminal brachytherapy administration. In general, if stenting aims palliation, then plastic stents are used if expected survival is <3-4 months, otherwise metallic stents are used as the former is relatively cheaper. In most series, 30-day mortality is >10%, median survival being 10 months, and most patients die due to the underlying malignancy. Mean patency rate of SEMS is 6-9 months with an occlusion rate of 30-40% by 6 months. Stent occlusion requiring re-intervention occurs in ~10-30% of the cases. [11],[12],[15],[17] In a study conducted by one of the authors, median stent patency was 147 days. In general, patency rate of stent is higher than internal-external drainage (ring biliary) catheter likely due to its larger caliber, less chances of blockage due to infections as they are not exposed externally, and no accidental dislodgement unlike ring biliary catheter. [17] The cost of procedure including hospitalization varies from hospital to hospital, whether government or private. The cost of biliary stent is approximately 30,000-70,000 Indian rupees. The cost of hardware (other than stent) for PTBD procedure is approximately 10,000-15,000 Indian rupees. Hospitalization charges vary significantly from government to private hospitals or centers.
ERCP with placement of plastic stent (polyethylene endoprosthesis) is another effective method of biliary drainage. It is the preferred procedure in cases of obstruction beyond the level of hilum, i.e. if the primary biliary confluence is patent as adequate biliary drainage can be accomplished by the placement of single stent. Furthermore, in such cases of low biliary obstruction, ERCP is preferred, as it is a safer procedure in comparison to PTBD. [18],[19],[20]
Absolute Relative
In inoperable malignancies causing biliary obstruction, ERCP with placement of plastic endoprosthesis or PTBD with metallic stenting remains the minimally invasive options. However, choosing a procedure over other depends on the level of obstruction, operator's expertise, and the level of postprocedural care provided to the patient. Distal biliary obstruction ERCP is unambiguously the preferred procedure worldwide as it is a comparably safer procedure with relatively fewer contraindications. Unlike PTBD, burden of percutaneous drainage catheter and bag is obviated which further compounds the psychological burden of terminally ill patients. In the current scenario, in cases of distal CBD obstruction, ERCP is the preferred technique unless contraindicated (vide supra), for which PTBD is done. [23],[24] Proximal biliary obstruction Opinion is divided regarding the choice of technique with nearly comparable results regarding overall patient's survival and procedure-related complication. However, at many institutions, PTBD is preferred in hilar isolation as ultrasound-guided puncture of appropriate segmental biliary radicle can be done, thus maximizing the drainage of functioning liver parenchyma. Further, malignant stricture is better negotiated in PTBD and the risk of inadvertent contrast instillation into isolated biliary segment is lesser as compared to ERCP. [3],[17],[25],[26],[27] Various studies comparing PTBD and ERCP in distal CBD block have reported that both these procedures have nearly equivalent technical success rate with comparable incidences of procedure-related complications and mortality [Table 6]. [1] The American College of Radiology (ACR) has recently proposed an evidence-based algorithmic approach for radiological management of malignant biliary obstruction. In the proposed criteria, various management options are rated based on their appropriateness for particular site of obstruction [Table 7]. In general, as per the ACR recommendations of the various management options, PTBD is preferred for hilar block whereas ERCP with stenting in distal block.
ACR Appropriateness Criteria® : Management of Benign and Malignant Biliary Obstruction, 2012 review [Table 8].
Due to recent advances in the procedural technique coupled with better hardware's availability, there has been a significant reduction in the overall morbidity and mortality (short-term) in cases of malignant obstructive jaundice. However, long-term prognosis remains dismal in malignant obstructive jaundice due to relentless dragging evolution of primary malignancy. Nonetheless, in the current scenario, PTBD is the recommended standard of palliative care for cases of obstructive jaundice as it improves the quality of life with definite immediate survival benefits. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]
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