Techniques of biliary drainage for acute cholecystitis: Tokyo Guidelines



# Introduction
Biliary drainage used to be a surgical procedure consisting of external biliary drainage done under local anesthesia -called "percutaneous cholecystostomy". With the popularization of ultrasonography, percutaneous transhepatic gallbladder drainage (PTGBD), which is an interventional procedure, has become a standard method. The usefulness of PTGBD as a drainage method for high-risk patients is endorsed by many case-series studies (level 4), 1-8 but its superiority over conventional treatment has not been proven by randomized controlled trials (RCTs) based on the highest level of evidence (level 2b). [bib_ref] Treatment of acute cholecystitis by direct-puncture bile aspiration with ultrasound image control, Mizumoto [/bib_ref] Percutaneous transhepatic gallbladder aspiration (PTGBA), is an alternative biliary drainage method in which the gallbladder contents are punctureaspirated without placing a drainage catheter. The usefulness of PTGBA has been reported only in case-series studies (level 4). [bib_ref] Treatment of acute cholecystitis in non-critically ill patients at high surgical risk:..., Chopra [/bib_ref] [bib_ref] Acute cholecystitis in high-risk patients: percutaneous cholecystostomy vs conservative treatment, Hatzidakis [/bib_ref] [bib_ref] Effectiveness of ultrasound-guided percutaneous transhepatic gallbladder aspiration (PTGBA) for acute calculous cholecystitis, Kutsumi [/bib_ref] Acalculous cholecystitis is known to occur in elderly or high-risk patients with poor systemic condition, and it can be treated by biliary drainage alone (level 4). [bib_ref] Percutaneous cholecystostomy in acute cholecystitis in high-risk patients: an analysis of 69..., Kiviniemi [/bib_ref] [bib_ref] Is percutaneous cholecystostomy the optimal treatment for acute cholecystitis in the very..., Sugiyama [/bib_ref] [bib_ref] Acute acalculous cholecystitis, Babb [/bib_ref] [bib_ref] Surgical treatment of biliary tract infections, Lillemoe [/bib_ref] This article describes the details of drainage procedures used for acute cholecystitis, and indicates the grades of recommendation for the procedures established by the Guidelines.

# Abstract
The principal management of acute cholecystitis is early cholecystectomy. However, percutaneous transhepatic gallbladder drainage (PTGBD) may be preferable for patients with moderate (grade II) or severe (grade III) acute cholecystitis. For patients with moderate (grade II) disease, PTGBD should be applied only when they do not respond to conservative treatment. For patients with severe (grade III) disease, PTG-BD is recommended with intensive care. Percutaneous transhepatic gallbladder aspiration (PTGBA) is a simple alternative drainage method with fewer complications; however, its clinical usefulness has been shown only by case-series studies. To clarify the clinical value of these drainage methods, proper randomized trials should be done. This article describes techniques of drainage for acute cholecystitis.

## Procedures for gallbladder drainage

## Percutaneous transhepatic gallbladder drainage (ptgbd)
PTGBD is an essential technique for nonoperative gallbladder drainage. After ultrasound-guided transhepatic gallbladder puncture is done with an 18-G needle, a 6to 10-Fr pigtail catheter is placed in the gallbladder, using a guidewire under fl uoroscopy (Seldinger technique; . The advantage of the technique is its simplicity. However, although bile aspiration and lavage are easily performed by this technique, it has disadvantages in that the drainage tube cannot be extracted until a fi stula forms around the tube (around 2 weeks) and there is a risk of dislocation of the tube. The superiority of PTGBD over conservative treatment has not be proven by RCTs (level 2b) [bib_ref] Acute cholecystitis in high-risk patients: percutaneous cholecystostomy vs conservative treatment, Hatzidakis [/bib_ref] Only the mandolin is removed and the external cylinder remains. c Backfl ow of bile is confi rmed. d A guidewire is inserted into the gallbladder. e After removal of the external cylinder, a drainage tube is passed over the guidewire into the gallbladder. The guidewire is then withdrawn, and the tube is fi xed to the skin ment 3 and less restriction of the patient's activity of daily living (ADL), but an RCT (level 2b) 12 has indicated that the drainage is less effective [fig_ref] Table 2: Comparisons of results for PTGBA and PTGBD [/fig_ref]. However, as it is known that the effect of drainage is enhanced when PTGBA is performed two times or more (level 4), [bib_ref] Effectiveness of ultrasound-guided percutaneous transhepatic gallbladder aspiration (PTGBA) for acute calculous cholecystitis, Kutsumi [/bib_ref] [bib_ref] Treatment of acute cholecystitis by direct-puncture bile aspiration with ultrasound image control, Mizumoto [/bib_ref] an RCT should be performed to confi rm the effect of PTGBA by comparing it with PTGBD not only in terms of drainage but also in terms of other outcomes, including complications and the effects on patients' ADL.

## Percutaneous transhepatic gallbladder aspiration (ptgba)
PTGBA is a method to aspirate bile via the gallbladder with a small-gauge needle under ultra sonographic guidance ; it is an easy low-cost bedside-applicable procedure, without X-ray guidance. It has various advantages as compared with PTGBD, such as the absence of complications, including those caused by tube displacement, as it requires no drainage tube manage- [bib_ref] Treatment of acute cholecystitis by direct-puncture bile aspiration with ultrasound image control, Mizumoto [/bib_ref] PTGBA, 58 98% 81% (94% a ) 2.5% -* P < 0.05 a PTGBA was performed twice or more Through the ERCP catheter, a hydrophilic guidewire was passed beyond the obstruction. c A radiofocus guidewire was inserted into the gallbladder. d An ENG-BD catheter was inserted into the gallbladder for drainage For PTGBA, considering the potential for bile leakage into the peritoneal cavity, a transhepatic puncture route is chosen, and the gallbladder contents should be completely aspirated until the gallbladder collapses, as shown by ultrasound-guided checking of the needle tip .
The use of a large-gauge (18-G) needle is convenient for aspirating highly viscous bile containing infl ammatory products and biliary sludge, but we should be careful to prevent bile leakage after removing the needle. While a small-gauge (21-G) needle has a lower risk of leakage after removal, aspiration of highly viscous bile is diffi cult with such needles and should be conducted while washing with saline containing antibiotics. Many stadies (level 2b, 4) 10-12 report the use of 21-G needles.

## Endoscopic nasogallbladder drainage (engbd)
ENGBD is an external drainage procedure done by placing a 5-to 7-Fr tube, using a guide-wire technique, after selective cannulation into the gallbladder . ENGBD can be used for patients with severe comorbid conditions, especially those with end-stage liver disease, in whom the percutaneous approach is diffi cult to perform. However, because it requires a diffi cult endoscopic technique, and relevant case-series studies have been conducted only at a limited number of institutions (level 4), [bib_ref] Effi cacy of endoscopic retrograde cholecystoendoprosthesis (ERCCE) for cholecystitis, Tamada [/bib_ref] [bib_ref] Drainage of the gallbladder in patients with acute acalculous cholecystitis by transpapillary..., Johlin [/bib_ref] [bib_ref] Endoscopic transpapillary gallbladder drainage (ETGBD) for the treatment of acute cholecystitis, Nakatsu [/bib_ref] [bib_ref] Endoscopic stenting of the gallbladder for symptomatic gallbladder disease in patients with..., Shrestha [/bib_ref] [bib_ref] Endoscopic naso-gallbladder drainage in the treatment of acute cholecystitis: alleviates infl ammation..., Toyota [/bib_ref] ENGBD has not been established as a standard method.
The Guidelines established the following grades of recommendation for gallbladder drainage, based on the currently available evidence.

## Q1. what procedure should be chosen when gallbladder drainage is required in acute cholecystitis?
by the Japanese Ministry of Health, Labour, and Welfare.
We also truly appreciate the panelists who co operated with and contributed signifi cantly to the International Consensus Meeting, held in Tokyo on April 1 and 2, 2006.
[fig] Fig: 1a-e. Percutaneous transhepatic gallbladder drainage (PTGBD) procedure. a A hollow needle (external cylinder with a mandolin) is inserted into the gallbladder. b [/fig]
[table] Table 2: Comparisons of results for PTGBA and PTGBD [/table]