How to drain the gallbladder: that is the question

Acute cholecystitis constitutes the most common complication of gallstone disease. Of the patients presenting to the emergency room with acute abdominal complaints, 3 % – 9 % have acute cholecystitis, and over 90 % of those have gallstones [1]. The standard of care is cholecystectomy, either as an emergency procedure or delayed after a cooling down period. However, if the patient has high surgical risk, prompt cholecystectomy is not an option. Techniques to decompress the gallbladder can be utilized instead, for example endoscopic or radiological drainage, which can be used as either a temporary or definitive solution. Each treatment option has its own benefits and adverse events. The most appropriate technique will depend on patient characteristics, presence of gallstones, future treatment plans, risk of recurrence, anatomical considerations, and availability of equipment and experience at each hospital.

In this issue of Endoscopy, Mohan et al. [2] report their findings from a systematic review and meta-analysis to compare gallbladder drainage techniques in patients unfit for surgery. A total of 72 studies investigating three techniques were included: endoscopic transpapillary gallbladder drainage (ETGBD), endoscopic ultrasound-guided gallbladder drainage (EUSGBD), and percutaneous gallbladder drainage (PCGBD). The authors found that EUSGBD demonstrated better clinical success (96.7 %) than ETGBD (88.1 %) and PCGBD (89.3 %), whereas technical success was highest for PCGBD (98.7 %), followed by EUSGBD (95.3 %). The authors recommend considering EUSGBD as a first-line approach when treating this patient population.

We compliment the authors for their thorough work. The study represents an in-depth interrogation of the available data and, in particular, adds to the current knowledge by reporting all-cause mortality. It reflects a well-designed, high-quality meta-analysis and systematic review, and provides clarity on the issue of the best methods for gallbladder drainage.

“The choice of technique depends mainly on the purpose of gallbladder drainage – temporary or definitive.”

There are, however, some drawbacks of the study, which preclude direct and broad implementation of the preferred drainage technique. First, the data mainly originate from retrospective studies, adding a significant risk of bias on reporting the clinical success. Second, the included studies were mainly carried out in tertiary-care referral centers, thus not reflecting common practice in general hospitals, where some of these techniques might not be available. Third, although the calculated pooled rates of all adverse events were comparable between ETGBD, EUSGBD, and PCGBD (albeit with statistical differences between some, as they are inherent to the technique used), a subtype analysis showed markedly higher all-cause mortality in the EUSGBD group (26 %, 9 studies, 398 patients). This included the prospective study by Walter et al., which showed overall mortality of 23 % [3]. The authors explain this very high mortality rate by the more thorough patient follow-up in the EUSGBD studies compared with the ETGBD and PCGBD studies. This would imply that mortality rates of the latter two techniques are much higher than reported in the included studies or indeed shown in the meta-analysis. Furthermore, it is not clear which particular stents were used in the EUSGBD studies. The currently used Hot Axios stent (Boston Scientific, Marlborough, Massachusetts, USA) seems to be safer than the previously used “cold” technique and might result in lower complication rates. Therefore, caution is warranted for advocating EUSGBD as the preferred method of gallbladder drainage when surgery is not an option.

Another important unresolved issue is whether there is a difference in surgical risk for interval cholecystectomy after endoscopic or percutaneous gallbladder drainage? A recent retrospective study found a nonsignificant trend to lower postoperative complications after an endoscopic gallbladder drainage technique was used [4]. Endoscopic drainage does not seem to hinder future cholecystectomy, which might be an important benefit. However, many questions are raised: Which technique is preferred for defect closure after stent removal? Is it better to place a lumen-opposing metal stent (LAMS) through the stomach or the duodenum? What about the timing for interval cholecystectomy? What is the patency duration of LAMS? Does stent diameter matter? Do they have to be replaced with pigtails as a permanent solution? These and other questions remain to be elucidated.

Although the authors report that this study is the first meta-analysis comparing the outcomes of ETGBD, EUSGBD, and PCGBD, a similar study was published in 2017 including 23 studies and 809 patients, which were mostly included in the current analysis [5]. Technical success for EUSGBD was 93 % and thus comparable. The authors concluded that endoscopic gallbladder drainage had similar success to PCGBD but appeared to be safer, and predicted an increase in endoscopic techniques in nonsurgical patients.

The recent revised Tokyo guidelines recommend PCGBD as the standard drainage method for surgically high-risk patients with acute cholecystitis [6]. We concur that PCGBD is more easily available in most hospitals, and seems to be the most sensible option in most cases despite the discomfort patients can experience with a percutaneous drain in place. On the other hand, ETGBD or EUSGBD could be considered in high-volume institutions when performed by skilled endoscopists. There is concern about the cost of these endoscopic techniques, but overall they might turn out to be the cheapest options. Refinement of the technique might come from cholangioscopy-assisted ETGBD if cannulation of the cystic duct fails. Although we, as interventional endoscopists, are excited about placing transmural stents such as LAMS, we are cautious about advocating EUSGBD as the treatment of choice for nonsurgical acute cholecystitis patients. Several considerations are necessary when deciding on the most appropriate technique for a particular patient, including the presence of gallstones and the inherent risk of recurrence, which might guide towards EUSGBD or ETGBD. Technical considerations, such as the safety of leaving LAMS permanently in place, whether or not to remove gallstones through the stent, whether or not to place a pigtail stent through the LAMS to prevent occlusion, and others have yet to be clarified. The choice of technique depends mainly on the purpose of gallbladder drainage – temporary or definitive. All these factors, as well as consultation with the hepatobiliary surgeons beforehand, need to be considered before selecting the gallbladder drainage technique.

• References

• 1 Strasberg SM. Acute calculous cholecystitis. N Engl J Med 2008; 358: 2804-2811
• 2 Mohan BP, Khan SR, Trakroo S. et al. Endoscopic ultrasound-guided gallbladder drainage, transpapillary drainage, or percutaneous drainage in high risk acute cholecystitis patients: a systematic review and comparative meta-analysis. Endoscopy 2020; 52: 96-106
• 3 Walter D, Teoh AY, Itoi T. et al. EUS-guided gall bladder drainage with a lumen-apposing metal stent: a prospective long-term evaluation. Gut 2016; 65: 6-8
• 4 Kaura K, Bazerbachi F, Sawas T. et al. Surgical outcomes of ERCP-guided transpapillary gallbladder drainage versus percutaneous cholecystostomy as bridging therapies for acute cholecystitis followed by interval cholecystectomy. HPB (Oxford) 2019; DOI: 10.1016/j.hpb.2019.10.1530.
• 5 Khan MA, Atiq O, Kubiliun N. et al. Efficacy and safety of endoscopic gallbladder drainage in acute cholecystitis: is it better than percutaneous gallbladder drainage?. Gastrointest Endosc 2017; 85: 76-87.e3
• 6 Mori Y, Itoi T, Baron TH. et al. Tokyo Guidelines 2018: Management strategies for gallbladder drainage in patients with acute cholecystitis (with videos). J Hepatobiliary Pancreat Sci 2018; 25: 87-95