**2.4 Step-up approach for walled of necrosis**

Open surgery is associated with a high morbidity and mortality in patients with WON. Consequently, minimally invasive surgical or endoscopic approaches have virtually replaced open necrosectomy in these patients [6]. The available evidence favors a step-up approach over the conventional techniques [7, 42–44]. In general, minimally invasive surgical step-up approach consists of percutaneous drainage followed by (if necessary) video assisted retroperitoneal debridement (VARD). Whereas, endoscopic step up approach includes ETD followed by (if necessary) endoscopic necrosectomy. Percutaneous catheter drainage can be used as an adjunct to ETD in cases with incomplete response or large collections with extension into paracolic gutter (**Figure 6**).

Several trials have compared endoscopic versus minimally invasive surgical methods of drainage in cases with WON [7, 45]. In a randomized trial by the Dutch Pancreatitis Study Group, there was no difference in the incidence of major complications or mortality between the endoscopic or minimally invasive surgical step-up approach (endoscopy: 43% vs. surgery: 45%, p = 0.88) [7]. However, the rate of

**Figure 6.** *Large pancreatic fluid collection extending into pelvis.*

pancreatic fistulas (5 vs 32%, p < 0.01) and the length of hospital stay were lower in the endoscopy group [7]. In another randomized trial including 66 patients with infected WON, ETD was associated with significantly reduced major complications (0.15 vs. 0.69), lowered costs (75,830 \$ vs. 117,492 \$), lower incidence of pancreatic fistula (0 vs. 28.1%), and increased quality of life as compared to minimally invasive surgery [45]. In a recent systematic review including two randomized trials and four observational studies, ETD was associated with lower mortality, risk of major organ failure, adverse events, and length of hospital stay [44]. These trials suggest that endoscopic step-up approach should be preferred over minimally invasive surgical step-up approach for the management of PFCs.

#### **2.5 Endoscopic vs. surgical drainage: pseudocysts**

Endoscopic and surgical cyst-gastrostomy have been compared in several studies [46–50]. Initial non-randomized trials found surgical drainage to be superior to endoscopic drainage of pseudocysts [50]. However, subsequent randomized studies concluded that endoscopic drainage achieves similar outcomes as compared to surgical drainage [46, 49, 47]. In addition, EUS guided cyst-gastrostomy is less invasive, cost saving, and associated with a shorter length of a post procedure hospital stay when compared with surgical cyst-gastrostomy [46, 47]. In a recent systematic review and meta-analysis including six studies (342 patients), there was no significant difference between surgical and endoscopic treatment success rates, adverse events, and recurrence for pancreatic pseudocysts [51]. To conclude, the current evidence suggests that endoscopic drainage is as efficacious as surgical cystgastrostomy for pseudocysts with shorter hospital stay and reduced costs.

#### **2.6 Endoscopic vs. percutaneous drainage**

Percutaneous catheter drainage remains an important modality even in the era of minimally invasive endoscopic or surgical treatments. In different studies, percutaneous drainage alone was successful in 35–50% of cases with WON [52]. Percutaneous drainage can be used as an adjunctive to endoscopic drainage in selected cases with large PFCs extending into paracolic gutters or pelvis. In addition, percutaneous drainage is useful in acute or ill-defined PFCs (<4 weeks) where endoscopic drainage may not be feasible. Percutaneous tract can also be utilized for endoscopic and VARD [43]. Having described all the major advantages of percutaneous catheter drainage, the major limitation remains the development of external pancreatocutaneous fistula which may be difficult to treat.

As compared to percutaneous approach, endoscopic drainage is associated with significantly better clinical success, a lower re-intervention rate, and a shorter hospital length of stay [53]. Therefore, percutaneous drainage is only performed in cases where either endoscopic drainage is not available or not feasible (ill-defined or distantly located collections).

#### **2.7 Dual modality drainage**

Dual modality drainage (DMD) involves the simultaneous or sequential use of endoscopic and percutaneous approaches for symptomatic PFCs. Several studies have concluded the utility of DMD in symptomatic PFCs especially WON [54, 55]. The proposed advantages of this technique include a quicker recovery and reduced chances of forming an external pancreato-cutaneous fistula. In the study by Gluck et al., the use of DMD was associated with reduced length of hospital stay, and less requirement of radiological or endoscopic interventions [55].

**15**

*Endoscopic Management of Pancreatic Fluid Collections: An Update*

This technique may be especially useful in cases with large WON especially those extending into the paracolic gutters [56]. In these cases, transmural approach

Trans-papillary drainage (TPD) of PFCs may be useful in certain scenarios as follows: (a) small size of cyst (<5 cm) communicating with main pancreatic duct (PD), (b) as an adjunct to ETD in cases with PD leak or disconnected PD, (c) chronic pancreatitis with an obstructed PD communicating with a pseudocyst, and (d) management of external pancreatic fistula after percutaneous or surgical drainage [22]. When used as a primary modality, TPD provides the path of least resistance for the pancreatic juice, thereby diverting it away from the cyst. There is a potential of cyst infection with TPD and therefore, antibiotics should be routinely given to these patients. TPD may be useful in preventing recurrences of PFCs following ETD in cases with PD leak and disconnected PD [57]. We do not routinely perform TPD as an adjunct to ETD in all the cases. In our practice, we evaluate the PD anatomy using an magnetic resonance cholangiopancreatogram (MRCP) prior to removal of stents placed during ETD. In cases with a PD stricture, leak or disconnection we attempt placing a trans-papillary PD stent. Subsequently, trans-papillary stents are removed or exchanged (as per the PD morphology) after 4–6 weeks. However, trans-papillary stenting may not be always feasible especially in cases with a disconnected PD. In these cases, transmural plastic stents can be left in situ and metal stents can be exchanged with plastic stents [58]. However, the latter approach needs to be substantiated by high quality randomized studies. Nevertheless, metal stents should be removed between 2 and 4 weeks irrespective of the PD anatomy due to the risk of buried

The literature regarding the efficacy of endoscopic drainage of PFCs in children is sparse. Unlike adults, the feasibility of drainage using an adult duodenoscope or EUS scope is questionable in smaller children. Nevertheless, emerging data indicates that EUS-guided drainage is feasible and effective in children with PFCs [59–63]. Our group evaluated the long-term outcomes in 30 children with PFCs using pigtail plastic stents [60]. Clinical success was documented in 93% of children at a median follow up of 829 days. The use of novel metal stents has also been described in pediatric age group [62, 61]. Nabi et al. used novel bi-flanged metal stents in 21 children with WON. Metal stents could be successfully placed in all the children, and clinical

The technique of ETD of PFCs using metal stents requires a series of steps including needle puncture, coiling of guidewire in the cyst cavity, balloon dilatation of the cystogastric tract, and finally, deployment of stent. With the availability of electrocautery-enhanced delivery systems, the deployment of metal stents can be achieved in a single step [64, 65]. Therefore, the drainage of PFCs using these "Hot Devices" is quicker and simpler. Currently, the electrocautery-enhanced delivery system is available with lumen apposing (Hot *AXIOS*) as well as biflanged metal

alone may not provide adequate drainage in these patients (**Figure 6**).

*DOI: http://dx.doi.org/10.5772/intechopen.89764*

**2.8 Trans-papillary drainage of PFCs**

stent syndrome and delayed bleeding.

**2.9 Endoscopic drainage of PFC in children**

success was achieved in 95% of children [62].

**3. Recent advancements**

stents (Hot *NAGI*).

This technique may be especially useful in cases with large WON especially those extending into the paracolic gutters [56]. In these cases, transmural approach alone may not provide adequate drainage in these patients (**Figure 6**).
