• Endoscopic retrograde cholangiopancreatography (ERCP) combines endoscopy and x-ray to diagnose and treat problems of the bile and pancreatic ducts. Compared to the traditional technique involving injection of contrast dye into the ducts with a catheter, using a guidewire technique to gain access to the bile duct probably reduces the risk of post-ERCP pancreatitis (PEP) and may also increase the success rate of gaining access to the bile duct.
• Future research in this area should focus on the effects of the guidewire technique in addition to other options for reducing the risk of PEP (for example, rectally administered anti-inflammatory drugs, a plastic tube inserted into the pancreatic duct).
What is post-ERCP pancreatitis (PEP)?
ERCP combines endoscopy (examination inside the body using a medical instrument called an endoscope) and x-ray to diagnose and treat problems of the bile and pancreatic ducts (structures that support the process of digestion). With the patient under sedation, an endoscope is passed down the oesophagus (windpipe) and into the small bowel, where the opening of the bile and pancreatic ducts (papilla) is located. A catheter is inserted through the endoscope and papilla into the bile duct. Contrast dye is injected into the bile duct, and x-rays are taken to look for gallstones or blockage. However, the major risk of ERCP is the development of pancreatitis (inflammation of the pancreas) due to irritation of the pancreatic duct by the contrast material or catheter, which can occur in 5% to 10% of all procedures. This may be self-limited and mild, but can also be severe and require hospitalisation. Rarely, it may be life-threatening. There are also small risks of bleeding or making a hole in the bowel wall.
What did we want to find out?
There are two techniques for gaining access to the bile duct during ERCP. The traditional technique (contrast) involves inserting a catheter into the papilla and injecting contrast dye to confirm access to the bile duct. However, contrast dye may be unintentionally injected into the pancreatic duct. A second technique (guidewire) involves using a guidewire to probe the papilla to gain access to the bile duct. Once an x-ray confirms the guidewire is in the bile duct, contrast dye is injected into the bile duct.
We wanted to find out:
• which technique for gaining access to the bile duct during ERCP works best to reduce the risk of PEP;
• which technique achieves better success in gaining access to the bile duct; and
• which technique causes fewer unwanted effects (for example, the need to use advanced techniques involving blind incision into the papilla to gain access to the bile duct, inadvertent entry of the pancreatic duct, bleeding, hole in the bowel wall, and death).
What did we do?
We searched for studies that compared the guidewire to the contrast technique in people undergoing ERCP for biliary or pancreatic diseases. We compared and summarized their results and rated our confidence in the evidence based on factors such as study methods and sizes.
What did we find?
We found 15 studies that involved 4426 people undergoing ERCP. The studies were conducted in various countries around the world. The biggest study was in 513 people, and the smallest study was in 88 people, with ages ranging from 18 to 96 years and roughly equal numbers of men and women. Nine studies declared no funding sources and conflicts of interest, while the other six studies did not report this information.
What are the main results of the review?
Compared to the contrast technique, using the guidewire technique probably reduces the risk of PEP and may increase the success rate of gaining access to the bile duct, and probably reduces the need to use advanced techniques to gain access to the bile duct. The guidewire technique may result in little to no difference in the risks of bleeding and hole in the bowel wall. There were no cases of procedure-related death.
What are the limitations of the evidence?
We are moderately confident that the guidewire technique reduces the risk of PEP and reduces the need to use advanced techniques to gain access to the bile duct, but it is possible that physicians who performed the ERCP and assessed the outcomes may be biased, as they were aware of which technique(s) they used during the procedures. We are less confident in the results for the success rate of gaining access to the bile duct, and the results of further research could differ from ours. We are also less confident in our results for the risks of bleeding and hole in the bowel wall because of the low number of reported events. We are moderately confident in our results for mortality due to no events reported in a large number of people.
How up-to-date is this evidence?
This review updates our previous review published in 2012. The evidence is up-to-date to February 2021.
There is moderate-certainty evidence that the guidewire-assisted cannulation technique probably reduces the risk of PEP compared to the contrast-assisted cannulation technique. There is low-certainty evidence that the guidewire-assisted cannulation technique may result in an increase in primary cannulation success. There is low- and very low-certainty evidence that the guidewire-assisted cannulation technique may result in little to no difference in the risk of bleeding and perforation. No procedure-related deaths were reported. Therefore, the guidewire-assisted cannulation technique appears to be superior to the contrast-assisted cannulation technique considering the certainty of evidence and the balance of benefits and harms. However, the routine use of guidewires in biliary cannulation will be dependent on local expertise, availability, and cost. Future research should assess the effectiveness and safety of the guidewire-assisted cannulation technique in the context of other pharmacologic or non-pharmacologic interventions for the prevention of PEP.
Cannulation techniques have been recognized as being important in causing post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). However, considerable controversy exists about the usefulness of the guidewire-assisted cannulation technique for the prevention of PEP.
To assess the effectiveness and safety of the guidewire-assisted cannulation technique compared to the conventional contrast-assisted cannulation technique for the prevention of PEP in people undergoing diagnostic or therapeutic ERCP for biliary or pancreatic diseases.
For the previous version of this review, we searched CENTRAL (the Cochrane Library), MEDLINE, Embase, CINAHL and major conference proceedings, up to February 2012, with no language restrictions. An updated search was performed on 26 February 2021 for the current version of this review. Two clinical trial registries, clinicaltrials.gov and WHO ICTRP, were also searched in this update.
Randomized controlled trials (RCTs) comparing the guidewire-assisted cannulation technique versus the contrast-assisted cannulation technique in people undergoing ERCP.
Two review authors conducted study selection, data extraction, and methodological quality assessment independently. Using intention-to-treat analysis with random-effects models, we combined dichotomous data to obtain risk ratios (RR) with 95% confidence intervals (CI). We assessed heterogeneity using the Chi² test (P < 0.10) and I² statistic (> 50%). To explore sources of heterogeneity, we conducted a priori subgroup analyses according to trial design, publication type, risk of bias, use of precut sphincterotomy, inadvertent guidewire insertion or contrast injection of the pancreatic duct (PD), use of a PD stent, cannulation device, and trainee involvement in cannulation. To assess the robustness of our results, we carried out sensitivity analyses using different summary statistics (RR versus odds ratio (OR)) and meta-analytic models (fixed-effect versus random-effects) and per-protocol analysis.
15 RCTs comprising 4426 participants were included. There was moderate heterogeneity among trials for the outcome of PEP (P = 0.08, I² = 36%). Meta-analyses suggest that the guidewire-assisted cannulation technique probably reduces the risk of PEP compared to the contrast-assisted cannulation technique (RR 0.51, 95% CI 0.36 to 0.72, 15 studies, moderate-certainty evidence). In addition, the guidewire-assisted cannulation technique may result in an increase in primary cannulation success (RR 1.06, 95% CI 1.01 to 1.12, 13 studies, low-certainty evidence), and probably reduces the need for precut sphincterotomy (RR 0.79, 95% CI 0.64 to 0.96, 10 studies, moderate-certainty evidence). Compared to the contrast-assisted cannulation technique, the guidewire-assisted cannulation technique may result in little to no difference in the risk of post-sphincterotomy bleeding (RR 0.87, 95% CI 0.49 to 1.54, 7 studies, low-certainty evidence) and perforation (RR 0.93, 95% CI 0.11 to 8.23, 8 studies, very low-certainty evidence). Procedure-related mortality was reported by eight studies, and there were no cases of deaths in both arms (moderate-certainty evidence). Subgroup analyses suggest that the heterogeneity for the outcome of PEP could be explained by differences in trial design. The results were robust in sensitivity analyses.