In Whipple's procedure, which anastomotic technique has lower leak rate; Pancreaticogastostomy or Pancreatojejunostomy?

A best evidence topic has been constructed using a described protocol. The three-part question addressed was: in patient with Whipple's procedure which anastomotic technique has lower leak rate pancreaticogastostomy (PG) or pancreatojejunostomy (PJ)? Using the reported search, 38 articles were found; out of this six studies were deemed to be suitable to answer the question. The outcomes assessed were incidence of anastomotic leaks (pancreatic fistula) in both techniques PG and PJ. In conclusion, the best evidence showed that PG anastomosis has lower incidence of pancreatic fistula in comparison to PJ anastomosis.


Introduction
This BET was designed using a framework outlined by the International Journal of Surgery [1]. This format was used because a preliminary literature search suggested that the available evidence is of insufficient quality to perform a meaningful meta-analysis. Pancreatic anastomosis is regarded by most surgeons as one of the most challenging steps of Whipple's procedure. Pancreatic anastomotic leakage is one of the main causes of post-operative morbidity and mortality. The aim from this article is to review which technique has the lower anastomotic leak rate Pancreaticogastostomy vs Pancreatojejunostomy? The unique part of this article is that it provides an evidence-based answers to the above mentioned clinical questions, using a systematic approach of reviewing the literature.

Clinical scenario
A senior surgical trainee is assisting in a difficult Whipple's procedure, the consultant is about to perform the pancreatic anastomosis, the trainee is wondering would it be better to perform PG or PJ in order to reduce the incidence of pancreatic leak? Exclusion criteria: case reports, systematic reviews, letters to the editor, conference abstracts.

Search outcome
A total of 38 papers were found using both search engines. Out of these 28 papers were excluded because they were irrelevant based on the titles and or the abstracts. Ten full-text articles were screened and assessed for eligibility. From these, six papers were identified to provide the best evidence to answer the question. The definition of pancreatic fistula used on the article based on the International Study Group for pancreatic fistula definition (ISGPF) [2]. Table 1 7

. Discussion
Pancreatic anastomotic leakage is one of the main causes of morbidity and mortality after Whipple's procedure [3]. The incidence of pancreatic fistula (PF) varies greatly in different reports due to the different definitions of fistula [4]. In our review most of the articles adopt the International Study Group for pancreatic fistula (ISGPF) definition [2]. Many techniques have been described for joining the pancreatic stump either with the jejunum or with the stomach, with or without internal or external drainage of the pancreatic duct [5]. However, there are still some conflicting results in the literature regarding which technique has the lower leak rate. In this review we have compared six of the largest randomized controlled trials that compare the incidence of pancreatic fistula among the patients who had PG and PJ.
In our review, Three randomized control trials showed no statically significant difference in the rate of pancreatic fistulas among the two techniques these were conducted by Nakeeb et [6], Duffas et al. [7], and Wellner et al. [8]. However, these trials have some limitations such as small sample size, lack of preoperative randomization and absence of subgroup analysis based on pancreatic duct diameter.
In the year 2000, Takano et al. [9] published an RCT in the British Journal of Surgery which showed that PG has significantly low incidence of pancreatic fistula in comparison to PJ. However the main limitation of this review is the small sample size. In 2013, Figueras et al. [10] published a relatively larger size single centre RCT, which also has the same conclusion that PG is superior to PJ with regards to the pancreatic fistula. Topal et al. [11] in the same year published the largest multicentre RCT; it was the only multicentre study to use a stratified design to assess the outcome of PG compared to PJ after. The result proved that PG has statistically significant lower rate of pancreatic fistula in comparison to PJ.

Clinical bottom line
According to the above articles, the best evidence showed that PG anastomosis is associated with lower rate of pancreatic fistula in comparison to PJ anastomosis. The recommendation of the authors is that PG is better than PJ, particularly with regard to the incidence of pancreatic fistula.

Limitation of this review
Most of the articles except two have small sample size and are single centre, also in most article there is lack of preoperative randomization and absence of subgroup analysis based on pancreatic duct diameter. Most articles didn't mention the period of post-operative follow up.
In order to overcome these limitations, the authors do recommend a well design, large multicentre randomized control trials with long period of follow up.

Ethical approval
Not applicable.

Sources of funding
None.

Author contribution
RI: conducted the literature search and wrote the paper. SA: assisted in the literature search and Writing of paper. HN: assisted in writing of paper. AA: assisted in the literature search, editing of writing.

Provenance and peer review
Not commissioned, externally peer-reviewed.

Declaration of competing interest
None.