Summary of findings
Description of the condition
Pancreatic fistula (PF) is one of the most common postoperative complications after pancreaticoduodenectomy, the operation of choice for resectable tumours of the pancreatic head as well as the distal common bile duct and ampulla of Vater (Diener 2008; Diener 2011; Iqbal 2008; Schmidt 2004). PF was first described by Smith in 1953, and the notion was further developed by Cameron et al in 1976 that PF can be caused by pancreatic disease, trauma or surgery. PF is defined as an abnormal communication between the pancreas and other organs due to leakage of pancreatic secretions from damaged pancreatic ducts. An external PF occurs when the pancreatic duct communicates with the abdominal wall, and is also known as a pancreaticocutaneous fistula, whereas an internal PF communicates with the peritoneal cavity, the mediastinum or other spaces. The pancreatic juice can lead to ascites, pleural effusions and enzymatic mediastinitis. This can be followed by the loss of bicarbonate-rich pancreatic fluid via the pancreatic fistula that can result in a hyperchloraemic or normal anion gap metabolic acidosis. If the volume of pancreatic juice lost from the body is large, acidosis can occur and is a serious problem (Cameron 1976; Smith 1953). The International Study Group on Pancreatic Fistula (ISGPF) defines PF as "output via an operatively placed drain or a subsequently placed percutaneous drain of any measurable volume of drain fluid on or after postoperative day three, with an amylase content greater than three times the upper normal serum value" (Bassi 2005). PF occurs in up to 56% of patients undergoing pancreaticoduodenectomy, and it is regarded as the major factor leading to morbidity and mortality in patients undergoing pancreaticoduodenectomy (Boettger 1999; Cullen 1994; Gouma 2000; Neoptolemos 1997; Satoi 2006; Satoi 2008; Yeo 1997). Various techniques have been suggested to prevent PF (reconstruction with pancreaticogastrostomy, modification of the pancreaticojejunal anastomosis technique, duct-to-mucosa anastomosis, mucosa-to-mucosa anastomosis, use of adhesive sealants, use of somatostatin and its analogues) but the optimal strategy is still unknown (Fingerhut 2009; Li 2009; Peng 2003; Wente 2007; Zeng 2008).
Description of the intervention
One of the possible preventive strategies is placement of pancreatic duct stents, either internally or externally (Berger 2009; Imaizumi 2006; Kamoda 2008; Kimura 2009; Pessaux 2011; Poon 2007; Roder 1999; Winter 2006). The use of an internal stent implies placement of a plastic catheter across the pancreaticojejunostomy anastomosis for drainage into the jejunum (Roder 1999). The use of an external stent implies placement of a plastic catheter into the main pancreatic duct for external drainage of pancreatic juice (Pessaux 2011; Poon 2007).
How the intervention might work
Given that PF is mainly caused by anastomotic leakage from the pancreaticojejunostomy anastomosis, the placement of an internal stent may be beneficial as it may direct pancreatic juice into the jejunum and thus protect the pancreaticojejunostomy anastomosis. The placement of external drainage may be beneficial as it may protect the pancreaticojejunostomy anastomosis by diverting pancreatic juice away from the anastomosis (Howard 2007; Imaizumi 2006; Kimura 2009; Poon 2007; Roder 1999).
Why it is important to do this review
PF is one of the most common complications after pancreaticoduodenectomy. The quest for a preventive strategy is therefore of paramount importance. Several studies have demonstrated that the use of pancreatic duct stents is associated with a lower risk of PF (Berger 2009; Kamoda 2008; Winter 2006). However, to date, there is no accord in the literature on whether the use of stents is beneficial and, if so, whether the use of internal or external stents is preferable.
To determine the absolute (that is comparison of stents versus no stents) and relative (that is comparison of internal versus external stents) value of pancreatic stents in patients undergoing pancreaticoduodenectomy.
Criteria for considering studies for this review
Types of studies
All randomized controlled trials (RCTs), irrespective of blinding, publication status, language or publication date, were included whereas all observational studies were excluded.
Types of participants
Patients (regardless of age, sex, or ethnic group) who underwent pancreaticoduodenectomy for benign or malignant pathologies of the pancreas or periampullary region. Both the studies that employed the definition of pancreatic fistula according to the International Study Group for Pancreatic Fistula (ISGPF) and those that used the John Hopkins definition were included. The operation of pancreaticoduodenectomy included both pylorus-preserving pancreaticoduodenectomy (PPPD) and the classical Whipple resection.
Patients who underwent emergency pancreaticoduodenectomy for trauma. Patients who were recruited before surgery but were found to have unresectable disease after laparoscopy or laparotomy.
Types of interventions
- RCTs comparing the use of stents versus no stents after pancreaticoduodenectomy
- RCTs comparing the use of internal stents versus external stents after pancreaticoduodenectomy
Any type of stents was allowed, depending on the preference of surgeons in the primary studies.
Types of outcome measures
An RCT had to report on the primary outcome and at least one of the following secondary outcomes to be included in the review.
Incidence of pancreatic fistula
- Length of hospital stay
- Need for reoperation
- Overall complications
- In-hospital mortality
Search methods for identification of studies
We designed the search strategy before searching. No language restrictions were applied during the search. All relevant published and unpublished RCTs were sought, irrespective of blinding, publication status or publication date.
A computerized literature search was conducted in:
- CENTRAL (Cochrane Central Register of Controlled Trials) (Appendix 1);
- MEDLINE (PubMed) (Appendix 2);
- EMBASE (Appendix 3);
- ISI Web of Science (Appendix 4);
- CBM (China Biological Medicine Database) (Figure 1);
Figure 1. Chinese BioMedical Literature Database (CBM) search strategy (Searched from 1970 to February 2011).
- CNKI (Chinese National Knowledge Infrastructure Database) (Figure 2);
Figure 2. Chinese National Knowledge Infrastructure Database (CNKI) search strategy (Searched from 1979 to February 2011).
- Wangfang (Database of Chinese Ministry of Science & Technology) (Figure 3);
Figure 3. Chinese Wangfang database search strategy (Searched from 1998 to February 2011)
- VIP (Database of Chinese Science and Technology Periodicals) (Figure 4).
Figure 4. Database of Chinese Science and Technology Periodicals search strategy (Searched from 1994 to February 2011)
The above databases were searched from 1950 to February 2011. The search was limited to studies in humans.
Searching other resources
The following trials registers were also searched:
- World Health Organization (WHO) International Trials Registry Platform search portal (http://www.who.int/trialsearch/);
- Australian New Zealand Clinical Trials Registry (ATCR) (http://www.anzctr.org.au/);
- International Standard Randomised Controlled Trial Number Register (ISRCTN) (http://www.isrctn.org/);
- ClinicalTrials.gov (http://www.clinicaltrial.gov/);
- Current Controlled Trials (http://www.controlled-trials.com/);
- Chinese Clinical Trial Register (http://www.chictr.org).
Data collection and analysis
The protocol was based on the guidelines of the Cochrane Upper Gastrointestinal and Pancreatic Diseases (UGPD) Group. We performed the systematic review according to the instructions given in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011).
Selection of studies
Titles and abstracts of all citations were screened independently by two review authors (ZY Dong and Z Wang). The full texts of eligible articles were retrieved for assessment. Two review authors independently applied the inclusion criteria to all of these potentially eligible studies. The authors had planned to resolve discrepancies in trial selection through discussion and a third review author (J Xu) would be asked for an opinion in order to reach consensus but, in the event, the views of the two authors were consistent.
A summary of the results of the search and included studies is shown in Figure 5.
|Figure 5. Study flow diagram.|
Data extraction and management
Two authors (ZY Dong, Z Wang) independently extracted data regarding patients' characteristics, study methods, interventions, and outcomes using a prespecified data extraction form. Disagreement was solved by consensus. We obtained the major data of included studies so there was no need to contact the authors of the original articles for details regarding methods and missing data, as we had planned in the protocol.
Assessment of risk of bias in included studies
Two review authors (ZY Dong, Z Wang) independently assessed the methodological quality of the considered studies. We used the quality checklist recommended in the Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (Higgins 2011). The quality checklist for assessing the risk of bias covered six headings (sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting bias, other potential sources of bias), where a response of 'Yes' indicated a low risk of bias, 'Unclear' indicated an uncertain risk of bias, and 'No' indicated a high risk of bias (Higgins 2011). Any discrepancies were resolved by discussion among all review authors. The final results were recorded in RevMan 5.1 (RevMan 2011) and two figures (Figure 6; Figure 7) were generated to illustrate the proportion of studies with each of the judgements.
|Figure 6. Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.|
|Figure 7. Risk of bias summary: review authors' judgements about each risk of bias item for each included study.|
1. Adequate sequence generation
Low risk. Adequate sequence generation is reported using one of following approaches: random number tables or generated random numbers from statisticians, computer-generated random numbers, central randomization (central voice systems or voice-response systems). Coin tossing or shuffling used to generate the allocation sequence before the trials commenced was also considered eligible. This was considered to have a low risk of selection bias.
Unclear risk. The report does not specify one of the adequate methods outlined above but only mentions "random". This was considered to have a moderate risk of selection bias.
High risk. Other methods of allocation, such as quasi-randomization, with a high risk of selection bias. These trials were excluded.
2. Allocation concealment
Low risk. Clearly indicated the the staff involved in recruitment of patients and patients themselves were not aware of the allocation.
Unclear risk. Concealed trials in which the authors didn't report the approach taken to conceal allocation were considered to have a moderate risk of selection bias.
High risk. Trials where allocation to a treatment option did not fall into one of the categories above or where there was no allocation concealment were considered to have a high risk of selection bias.
Low risk. Blinding was considered to be by a good method, double blinding was assumed when participants and results assessor were masked. Trials were considered as having a low risk of both performance and detection bias.
Unclear risk. Single blinding for the results assessor was considered as having a moderate risk of both performance and detection bias. If single blinding was performed for participants but not the results assessor, the trial was considered to have a moderate risk of both performance and detection bias.
High risk. Open label study, non-blinding was considered to result in a high risk of both performance and detection bias.
4. Incomplete outcome data
Low risk. According to the sample size, number of lost patients < 5% was considered to have a low risk of incomplete data bias.
Unclear risk. According to the sample size, number of lost patients between 5% and 10% was considered as having a moderate risk of incomplete data bias.
High risk. According to the sample size, number of lost patients > 15% was considered as having a high risk of incomplete data bias.
5. Selective reporting bias
Where only favourable outcomes were reported and not any unfavourable ones.
6. Other potential sources of bias
Where a non-inferiority trial was used, conflicts of interest.
Measures of treatment effect
The data from each study were considered according to the intention-to-treat (ITT) principle. For dichotomous variables, we determined relative risk (RR) with 95% confidence interval (CI) to interpret the results. Continuous variables were estimated as the difference in means (MD) along with the corresponding 95% CI. For the same outcomes measured with different scales in different studies we used standardized mean differences (SMD) with 95% CI for analysis. Two authors entered all data into RevMan 5.1 (RevMan 2011).
Unit of analysis issues
The search strategy found five RCTs suitable for inclusion in this review. No unit of analysis issues were anticipated.
Dealing with missing data
All necessary data were available from the included trials. The authors of the primary studies were contacted with the request to provide missing data. When the authors of primary studies did not reply the available data were used for analysis.
Assessment of heterogeneity
We assessed two types of heterogeneity: statistical, and clinical and methodological heterogeneity.
For statistical heterogeneity, we evaluated the I² statistic and Chi² test for each outcome analysed. We considered a P value less than 0.1 and an I² value more than 75% as high heterogeneity, and an I² value less than 25% as low heterogeneity. We looked for the cause when heterogeneity was found.
Whether heterogeneity was clinical or methodological was assessed by clinical knowledge. We assessed clinical heterogeneity through comparing characteristics of participants, study designs and interventions. We then divided the studies into four different groups, according to the different interventions.
Assessment of reporting biases
Funnel plots were not used as the number of included studies was less than 10.
The data analysis was performed using the meta-analysis software Review Manager (RevMan 2011). A random-effects model was used in all analyses.
Subgroup analysis and investigation of heterogeneity
We intended to perform subgroup analysis as follows, if possible.
- Studies with low risk of bias versus studies with high risk of bias.
- Adult patients versus older patients.
- Participants with mild disease versus those with severe disease.
- Plastic stents versus metal stents.
- Different drainage times.
- Different duration of disease or hospital stay.
We considered these six items when analysing the results. We performed subgroup analysis on stents versus no stents (internal stents versus no stents; external stents versus no stents).
At protocol stage we stated that we may perform sensitivity analyses to explore the stability and reliability of the evidence, to enhance the strength of the evidence. However, there were only five included studies across the comparison groups.
Description of studies
Results of the search
Figure 5 provides the details of the search process. A total of 32 studies were identified through electronic searches of CENTRAL in The Cochrane Library (n = 120), MEDLINE (n = 670), EMBASE (n = 146), ISI Web of Science search strategy (n = 30), and the four Chinese Databases (CBM, VIP, CNKI, Wangfang) (n = 633).
In addition, six relevant ongoing trials were found.
Five RCTs that included a total of 656 patients undergoing pancreaticoduodenectomy met all of the inclusion criteria (Kamoda 2008; Pessaux 2011; Poon 2007; Tani 2010; Winter 2006). The characteristics of the included trials are presented in Table 1 and Characteristics of included studies.
We excluded 13 references for the reasons listed in the table Characteristics of excluded studies.
Risk of bias in included studies
The majority of studies reported the use of randomly generated number patterns or random number tables (Poon 2007; Tani 2010; Winter 2006). In one trial, it was mentioned that the process was 'randomised', but no further details were provided (Kamoda 2008). In two trials the allocation concealment was considered to be of high quality, sealed envelopes and standards of reporting random trials flow diagram (Poon 2007; Tani 2010). In one trial the allocation concealment was considered to be adequate as a 'generated number pattern' was used (Winter 2006).
There was no mention of patient or assessor blinding in all the included trials. Thus, they have all been assigned a moderate risk of bias.
Incomplete outcome data
All the included trials had adequately matched participants in the two groups and were free from baseline imbalance bias. All trials had adequate follow-up. Two trials (Kamoda 2008; Winter 2006) reported post-randomization withdrawal of patients. These patients were excluded from the analysis but the rate of loss to follow-up was less than 10%, so these trials were considered to have a low risk of incomplete outcome data bias.
All the trials reported on the primary outcome and were considered to be at low risk of selective outcome reporting bias. All the trials reported on sample size calculations.
Other potential sources of bias
The source of funding was not described in any of the trials.
Effects of interventions
Stents versus no stents
Three RCTs (Pessaux 2011; Poon 2007; Winter 2006) that incorporated a total of 502 patients who underwent pancreaticoduodenectomy were analysed. The risk of pancreatic fistula (PF) did not differ significantly between the groups: relative risk (RR) 0.81 (95% CI 0.59 to 1.10, P = 0.18) ( Analysis 1.1). The use of stents did not result in a statistically significant change in the risk of in-hospital mortality (RR 0.64; 95% CI 0.23 to 1.77, P = 0.39) ( Analysis 1.2). There was no statistically significant difference in need for reoperation between the two groups (RR 0.67; 95% CI 0.36 to 1.22, P = 0.19) ( Analysis 1.3). The total hospital stay was shorter in the external stents group in comparison with the no stents group (RR -0.40; 95% CI -0.71 to -0.08, P = 0.01) ( Analysis 1.4). The use of stents did not result in a statistically significant difference in the risk of wound infection (RR 0.62; 95% CI 0.24 to 1.59, P = 0.32) ( Analysis 1.5). The incidence of PF was: for Poon 2007, 10% (6/60) in the stented group and 35% (21/60) in non-stented group; for Winter 2006, 15% (25/172) in the stented group and 9% (15/175) in the non-stented group; for Pessaux 2011, 18% (14/77) in the stented group and 32% (26/81) in the non-stented group.
Subgroup analysis - internal stents versus no stents group
One RCT (Winter 2006) that incorporated a total of 234 patients who underwent pancreaticoduodenectomy was analysed. The incidence of PF did not differ significantly between the no stents group and the internal stents group (RR 1.23; 95% CI 0.78 to 1.94, P = 0.36) ( Analysis 2.1). However, this difference became statistically significant by adopting the random-effects model. The use of internal stents did not result in a statistically significant difference in in-hospital mortality (RR 0.52; 95% CI 0.10 to 2.77, P = 0.44) ( Analysis 2.2). There was no statistically significant difference for reoperation between the two groups (RR 0.52; 95% CI 0.18 to 1.47, P = 0.22) ( Analysis 2.3). The total hospital stay was shorter in the no stents group (median of seven days) than in the internal stents group (median of eight days). The use of internal stents did not result in a statistically significant difference in major complications (intra-abdominal abscess, wound infection) (RR 0.97; 95% CI 0.79 to 1.18, P = 0.73) ( Analysis 2.5).
Subgroup analysis - external stents versus no stents group
Two RCTs (Pessaux 2011; Poon 2007) that incorporated a total of 278 patients who underwent pancreaticoduodenectomy were analysed. The incidence of PF was significantly lower in the external stents group compared to the no stents group (RR 0.55; 95% CI 0.35 to 0.88, P = 0.01) ( Analysis 3.1). The use of external stents did not result in a statistically difference in in-hospital mortality (RR 0.72; 95% CI 0.20 to 2.60, P = 0.62) ( Analysis 3.2). There was no statistically significant difference in reoperation between the two groups (RR 0.76; 95% CI 0.36 to 1.60, P = 0.47) ( Analysis 3.3). The total hospital stay was shorter in the external stents group than the no stents group, there was a statistically significant difference between the two groups (RR -4.32; 95% -7.45 to -1.19, P = 0.007) ( Analysis 3.4). The incidence of major complications (delayed gastric emptying, wound infection) was significantly lower in the external stents group compared to the no stents group (RR 0.48; 95% CI 0.25 to 0.92, P = 0.03) ( Analysis 3.5).
Internal stents versus external stents
Two RCTs (Kamoda 2008; Tani 2010) that incorporated a total of 143 patients undergoing pancreaticoduodenectomy were analysed. The incidence of PF did not differ significantly between the groups (RR 1.22; 95% CI 0.65 to 1.92, P = 0.69) ( Analysis 4.1). The use of internal stents did not result in a statistically significant in-hospital mortality (RR 0.33; 95% CI 0.01 to 7.99, P = 0.50) ( Analysis 4.2). One RCT (Tani 2010) reported on reoperation, there was no statistically significant difference in reoperation between the two groups. One RCT (Kamoda 2008) reported total hospital stay, the total hospital stay was not statistically significantly different in the internal stents group compared with the external stents group (RR -0.30; 95% CI -9.76 to 9.16, P = 0.95) ( Analysis 4.4). The use of internal stents did not result in a statistically significant difference in major complications (intra-abdominal abscess, delayed gastric emptying, events of pancreatitis, wound infection) (RR 0.99; 95% CI 0.47 to 2.09, P = 0.99) ( Analysis 4.5). The incidence of PF was: for Kamoda 2008, 45% (10/22) in the external stented group and 38% (8/21) in the internal stented group; for Tani 2010, 20% (10/50) in the external stented group and 26% (13/50) in the internal stented group.
A total of six unpublished trials on the use of stents for the prevention of PF following pancreaticoduodenectomy have been found, including two studies that have been completed but not published yet (see Characteristics of ongoing studies). We will include these new RCTs in future updates.
Summary of main results
This systematic review, incorporating a total of five trials with 656 patients undergoing pancreaticoduodenectomy with or without pancreatic duct stenting, found no significant difference in terms of clinically meaningful outcomes between patients who had stents and those who did not have stents during pancreaticoduodenectomy. However, in a subgroup analysis it was found that the use of external stents, when compared with no stents, may be associated with a significant reduction in the risk of pancreatic fistula, the incidence of complications (delayed gastric emptying, wound infection) and a significantly shortened length of hospital stay (P < 0.05).
Overall completeness and applicability of evidence
The use of stents in patients undergoing pancreaticojejunostomy (PJ) was first reported in 1986 (Manabe 1986). It was followed by several published reports that further advocated this technique (Hamanaka 1994; Hiraoka 1993; Roder 1999). Theoretically, the stent may provide some protection of the PJ anastomosis against activated pancreatic enzymes by directing the exocrine secretions into the jejunal lumen, and it may help to facilitate a precise placement of sutures through the pancreatic parenchyma or duct when performing the PJ anastomosis (Roder 1999; Winter 2006). Several factors were reported to influence the success of stenting in preventing a pancreatic fistula. These included the stent's material, stent's size and length, timing of stent removal, and quality of the pancreatic remnant (Kamoda 2008; Ohwada 2002; Tani 2010; Winter 2006).
Unfortunately, we were not able to assess these factors in the meta-analysis as the size of the stents used was not reported in all the included studies. The typical description in the report was that 'the largest sized that could be easily passed into the pancreatic duct" was used (Winter 2006).
Quality of the evidence
A total of five studies met our inclusion criteria. All studies were reported as RCTs, but only three reported on the use of sealed centrally prepared random numbered envelopes. Three trials used intention-to-treat analysis, the others used a per protocol analysis. Two trials indicated the number of dropouts. Only one study did not describe whether informed consent was gained. Four of five trials performed sample size calculations.
Potential biases in the review process
The operation included two modifications, pylorus preserving pancreaticoduodenectomy (PPPD) and classical Whipple, and this might introduce clinical heterogeneity. The length of the external stents varied between the trials and was mainly determined by practical considerations in individual patients. It is also worth noting that the stents were manufactured by different companies. Thus, the quality of stents might be different, which in its turn could be a source of bias. Another possible bias in the included trials is that the timing of stent removal varied greatly between the studies, and this might influence the incidence of pancreatic fistula.
Another limitation is that the economic benefit of the stents was not analysed in the primary studies. This review did not analyse soft versus hard pancreatic remnant. While it was reported that soft pancreatic remnant is associated with a significantly higher risk of pancreatic fistula, no data were available in the primary studies to analyse this aspect (Tani 2010). One of the limitations of this systematic review is the limited number of RCTs available. There was only one study comparing internal pancreatic duct stents with no stents following pancreaticoduodenectomy, one study comparing external pancreatic duct stents with no stents, and two studies comparing internal pancreatic duct stents with external stents. Nevertheless, the trials included in this systematic review were all randomized and three of four studies were of high methodological quality.
Agreements and disagreements with other studies or reviews
This systematic review confirms that the use of external stents has the possible advantages of reducing the incidence of pancreatic fistulae and length of hospital stay as reported in a retrospective study (Poon 2007).
Implications for practice
This systematic review suggests that the use of external pancreatic duct stenting might be associated with a reduced risk of pancreatic fistulas and shortened length of hospital stay after pancreaticoduodenectomy. It suggests that external stents have benefits, but the evidence from the included trials is insufficient to decide on internal stents.
Implications for research
Further randomized clinical trials are needed to evaluate the use of pancreatic duct stents. These trials have to have a sufficient sample size and should adopt blinded outcome assessment by researchers. Pancreatic fistula must be defined using a consistent definition. These trials should be rigorously reported according to the recommendations of the updated CONSORT Statement from the CONSORT group (Schulz 2010).
We thank Karin Dearness for modifying and editing our protocol and review, Racquel Simpson, the Trials Search Coordinator, for developing the search strategy and identifying resources; and the other team members of the Cochrane Upper Gastrointestinal and Pancreatic Diseases (UGPD) Group for help during the development of this review.
Data and analyses
- Top of page
- Summary of findings [Explanations]
- Authors' conclusions
- Data and analyses
- What's new
- Contributions of authors
- Declarations of interest
- Sources of support
- Index terms
Appendix 1. CENTRAL search strategy (up to February 2011)
- Pancreatic Fistula/
- (pancrea$ adj3 fistula$).mp. [mp=title, original title, abstract, mesh headings, heading words, keyword]
- Gastric Fistula/
- (anastomo$ adj3 leak$).mp.
- (pancrea$ adj2 leak$).mp.
- Postoperative Complications/co, di, mo, pc, rh, su, th [Complications, Diagnosis, Mortality, Prevention & Control, Rehabilitation, Surgery, Therapy]
- exp Postoperative Complications/co, di, mo, pc, rh, su, th [Complications, Diagnosis, Mortality, Prevention & Control, Rehabilitation, Surgery, Therapy]
- whipple procedure.mp.
- Catheterization, Peripheral/
- Catheters, Indwelling/
- 6 and 17
Appendix 2. MEDLINE search strategy (searched from 1950 to February 2011)
- randomized controlled trial.pt.
- controlled clinical trial.pt.
- drug therapy.fs.
- (animals not (humans and animals)).sh.
- 9 not 10
- exp Pancreatic Fistula/
- (pancrea$ adj3 fistula$).mp.
- *Gastric Fistula/
- (anastomo$ adj3 leak$).mp.
- (pancrea$ adj2 leak$).mp.
- exp Postoperative Complications/co, mo, pc, rh, su, th [Complications, Mortality, Prevention & Control, Rehabilitation, Surgery, Therapy]
- exp Pancreaticoduodenectomy/ae, mo [Adverse Effects, Mortality]
- Pancreaticojejunostomy/ae, mo [Adverse Effects, Mortality]
- Prosthesis Design/
- exp Stents/
- pancreatic duct$ holder$.mp.
- *Catheterization, Peripheral/
- exp Catheters, Indwelling/
- supporting tube$.mp.
- exp suction/
- 17 and 30
- 11 and 31
Appendix 3. EMBASE search strategy (searched from 1950 to February 2011)
- Clinical trial/
- Randomized controlled trial/
- Single-Blind Method/
- Double-Blind Method/
- Cross-Over Studies/
- Random Allocation/
- Randomi?ed controlled trial$.tw.
- Random allocation.tw.
- Randomly allocated.tw.
- Allocated randomly.tw.
- (allocated adj2 random).tw.
- Single blind$.tw.
- Double blind$.tw.
- ((treble or triple) adj blind$).tw.
- Prospective study/
- Case study/
- Case report.tw.
- Abstract report/ or letter/
- 20 not 24
- exp Pancreatic Fistula/
- (pancrea$ adj3 fistula$).mp.
- *Gastric Fistula/
- exp anastomosis leakage/co, pc, rh, si, su [Complication, Prevention, Rehabilitation, Side Effect, Surgery]
- (anastomo$ adj3 leak$).mp.
- (pancrea$ adj2 leak$).mp.
- postoperative complication/co, pc, rh, si, su, th [Complication, Prevention, Rehabilitation, Side Effect, Surgery, Therapy]
- exp endoprosthesis loosening/
- Prosthesis Design/
- exp Stent/
- pancreatic duct$ holder$.mp.
- *Catheterization, Peripheral/
- exp Catheters, Indwelling/
- supporting tube$.mp.
- exp drain/
- exp surgical drainage/
- exp suction drainage/
- 32 and 45
- 25 and 46
Appendix 4. ISI Web of Science search strategy (up to February 2011)
1) TS =((ampullary carcinoma) OR (Malignant Tumor of ampullary) OR (Benign Tumour of ampullary) OR (Vater ampullary carcinoma) OR (distal bile duct carcinoma) OR (cholangiocarcinoma) OR (bile duct neoplasms) OR (pancreatic head carcinoma) OR (pancreatic head adenocarcinoma) OR (duodenal carcinoma) OR (duodenal papilla carcinoma) OR(Chronic Pancreatitis) OR (Pancreatic neoplasms) OR (adenocarcinom* panc* )OR (panc* tumor*) OR (panc* carc*) OR (panc* cancer*) OR (panc* neoplas*))
2) TS = ((randomized controlled trial) OR RCT OR random* OR (random allocation) OR (controlled clinical trial) OR randomized OR placebo OR randomly OR trial OR groups AND humans
3) TS = (pancreaticojejunostom* OR pancreatojejunostom* OR pancreatogastrostomy OR pancreaticoduodenal OR pancreaticoduodenectomy OR pancreaticoduodenectom* OR pancreatoduodenectom* OR duodenopancreatectom* OR duodenopancreatectom* OR (pylorus preserving Panceaticoduodenectomy) OR (extensive duodenopancreatectomy’) OR (binding pancreatico-jejunostomy) OR (Child procedure) OR (Whipple procedure) OR (classic Whipple) OR PD OR PPPD OR PPW OR SPD OR CW
5) 3) OR 4)
6) 1) and 2) and 5)
Last assessed as up-to-date: 4 April 2011.
Contributions of authors
Zhiyong Dong drafted the protocol, designed the search strategy, and performed the literature searches, then drafted the final review.
Maxim S Petrov revised the protocol, developed the methodology section of the protocol, and revised the final review.
Jin Xu provided advice on the protocol and revised the review and gave advice on the clinical content of the review.
Zhiyong Dong and Zhen Wang independently performed data extraction, data management and assessed included studies.
Declarations of interest
Sources of support
- The First Affiliated Hospital of Guangxi Medical University, China.
- The University of Auckland, New Zealand.
Medical Subject Headings (MeSH)
MeSH check words