Drainage of peripancreatic-fluid collections: is EUS really necessary?

Pancreatic fluid collections: Clinical manifestations, diagnostic evaluation and management

Pancreatic fluid collections (PFC), including pancreatic pseudocysts and walled-off pancreatic necrosis, are a known complication of severe acute pancreatitis. A majority of the PFCs remain asymptomatic and resolve spontaneously. However, some PFCs persist and can become symptomatic. Persistent PFCs can also cause further complications such as the gastric outlet, intestinal, or biliary obstruction and infection. Surgical interventions are indicated for the drainage of symptomatic sterile and infected PFCs. Management of PFCs has evolved from a primarily surgical or percutaneous approach to a less invasive endoscopic approach. Endoscopic interventions are associated with improved outcomes with lesser chances of complications, faster recovery time, and lower healthcare utilization. Endoscopic ultrasound-guided drainage of PFCs using lumen-apposing metal stents has become the preferred approach for the management of symptomatic and complicated PFCs.

Endoscopic Ultrasound-guided Bilio-pancreatic Drainage

The echoendoscopic biliary drainage is an option to treat obstructive jaundices when endoscopic retrograde cholangiopancreatography (ERCP) drainage fails. These procedures compose alternative methods to the side of surgery and percutaneous transhepatic biliary drainage, and it was only possible by the continuous development and improvement of echoendoscopes and accessories. The development of linear sectorial array echoendoscopes in early 1990 brought a new approach to diagnostic and therapeutic dimension on echoendoscopy capabilities, opening the possibility to perform punction over direct ultrasonografic view. Despite of the high success rate and low morbidity of biliary drainage obtained by ERCP, difficulty could be found at the presence of stent tumor ingrown, tumor gut compression, periampullary diverticula and anatomic variation. The echoendoscopic technique starts performing punction and contrast of the left biliary tree. When performed from gastric wall, the access is made through hepatic segment III. From duodenum, direct common bile duct punction. Diathermic dilatation of the puncturing tract is required using a 6-Fr cystostome and a plastic or metal stent is introducted. The techincal success of hepaticogastrostomy is near 98%, and complications are present in 20%: pneumoperitoneum, choleperitoneum, infection and stent disfunction. To prevent bile leakage, we have used the 2-stent techniques. The first stent introduced was a long uncovered metal stent (8 or 10 cm) and inside this first stent a second fully covered stent of 6 cm was delivered to bridge the bile duct and the stomach. Choledochoduodenostomy overall success rate is 92%, and described complications include, in frequency order, pneumoperitoneum and focal bile peritonitis, present in 14%. By the last 10 years, the technique was especially performed in reference centers, by ERCP experienced groups, and this seems to be a general guideline to safer procedure execution. The ideal approach for pancreatic pseudocyst (PPC) puncture combines endos-copy with real time endosonography using an interventional echoendoscope. Several authors have described the use of endoscopic ultrasound (EUS) longitudinal scanners for guidance of transmural puncture and drainage procedures. The same technique could be used to access a dilated pancreatic duct in cases in which the duct cannot be drained by conventional ERCP because of complete obstruction.

Endoscopic ultrasonography-guided pancreatic drainage

Surgery for pancreatic pseudocysts (PPCs) may be associated with high rates of complication and mortality. Since its introduction in the late 1980s, endoscopic drainage of PPCs has become established as an alternative nonsurgical approach. The obvious limitation of this technique is its relatively blind approach. The ideal approach for PPC puncture combines endoscopy with real-time endosonography using an interventional echoendoscope. Endoscopic ultrasonographic longitudinal scanners can be used for guidance of transmural punctures and drainage procedures, as well as to access a dilated pancreatic duct if the duct cannot be drained by conventional methods because of complete obstruction. In this chapter, we will review the indications, techniques and clinical algorithm for EUS-guided pseudocyst drainage and pancreaticogastrostomy.

Pancreatic pseudocyst drainage guided by endoscopic ultrasound

Pancreatic pseudocysts can be managed conservatively in the majority of patients but some of them will require surgical, endoscopic or percutaneous drainage. Endoscopic drainage represents an efficient modality of drainage with a high resolution rate and lower morbidity and mortality than the surgical or percutaneous approach. In this article we review the endoscopic pseudocyst drainage procedure with special emphasis on technical details.

Endoscopic ultrasound in the evaluation of pancreaticobiliary disorders

The close proximity of the endoscopic ultrasound probe to the pancreas coupled with the ability to perform fine needle aspiration has made endoscopic ultrasound an extremely important technique for the evaluation of both benign and malignant pancreaticobiliary disorders. In parallel to the widespread importance of diagnostic endoscopic ultrasound, the therapeutic and interventional applications of this procedure are expanding and may become a major breakthrough in the management of pancreaticobiliary diseases. This article focuses on the utility and recent advances of endoscopic ultrasound in the diagnostic evaluation pancreaticobiliary disorders and analyses the data of well established interventional procedures such as celiac plexus neurolysis and pseudocyst drainage. Moreover, the more innovative procedures, such endoscopic ultrasound-guided biliary and pancreatic ducts access and drainage and the experimental use of direct endoscopic ultrasound-guided therapy of both solid and cystic pancreatic lesions will also be reviewed.