Endoscopic retrograde cholangiopancreatography (ERCP) is a technique which combines endoscopic and radiological vision and allows for therapeutic procedures on pathologies of the pancreas and bile duct.

ERCP is a generally well tolerated procedure, nonetheless it is a complex technique that has a higher frequency of complications compared to most endoscopic procedures that can even be life-threatening. These complications are related to patient characteristics, experience of the endoscopist performing the procedure, and specific factors to the technique. Due to its complexity, quality assurance, operator training and auditing are required to increase success and minimize complications.

There are quality indicators suggested by the main scientific societies in relation to technical aspects and complications, recommending their monitoring and auditing. Most endoscopy units lack records to monitor quality and complications, which prevents the assessment of quality and the identification of areas for improvement.

Given the lack of evidence of the quality of ERCP in the Spanish population, the investigators will be conducting a multicenter, national prospective study that will include subjects who undergo ERCP.

Patient data and technical aspects of the procedure will be recorded and all included patients will be monitored to identify complications. The quality indicators obtained within the registry will be compared with those established by scientific societies and the relationship between complications and technical factors will be analyzed.

Currently, endoscopic retrograde cholangiopancreatography (ERCP) is a well-established procedure that is in continuous development, with an incidence and severity of adverse events (AEs) that differ substantially from those related to other endoscopic procedures, reaching up to 14.7% and with a mortality rate of 0.7%, even in expert centers 1. For this reason, it is essential to ensure the quality of ERCP procedures, requiring optimal training, capacity building and auditing to increase the success of the procedure and minimize the risk of complications 2.

In recent years, the evaluation of the quality of ERCP has gained interest among health professionals and patient organizations. In 2018, the European Society of Gastrointestinal Endoscopy (ESGE) and the United European Gastroenterology (UEG) published key quality recommendations for ERCP and endoscopic ultrasonography with the aim of encouraging healthcare professionals to implement these performance targets at national level 3. For ERCP there are 5 recommendations including adequate antibiotic prophylaxis before ERCP (at least 90%), biliary cannulation rate (at least 90%), adequate stent placement in patients with sub-hilum obstruction (at least 95%), removal of bile duct stones (at least 90%) and post-ERCP pancreatitis (less than 10%).

Following this line, endoscopists in the Netherlands have been using a mandatory nationwide quality register since 2016 (Trans.IT database; Rotterdam, the Netherlands), which provides information on the quality of ERCP 4. They have recently published the analysis of this register in relation to the ESGE quality recommendations. 5671 procedures performed by 57 endoscopists in 11 centres were included. Three key quality indicators were met: successful biliary cannulation, adequate placement of stents for biliary obstruction and removal of bile duct stones with a high overall success rate. These robust data from routine clinical practice also allow us to identify areas for improving the quality of ERCP, for example, successful cannulation of native papillae below 90% for endoscopists performing fewer than 50 procedures per year or the rate of adequate placement of biliary stents below 90% in endoscopists performing fewer than 25 procedures per year 5. Unfortunately, the rate of pancreatitis, which is the most appropriate indicator of the rate of adverse events, was not evaluated in this registry.

In our view, the collection of data at a national level is of undoubted value to identify areas for improvement and to guarantee quality in ERCP, however, there are no state databases in our setting.

The present study aims to evaluate the quality indicators of ERCP recommended by the ESGE-UEG in a Spanish prospective registry and to describe the real incidence of adverse events in clinical practice, and their association with technical aspects of the procedure.

Inclusion Criteria:

All consecutive patients who have undergone an ERCP at participating centres from 1 November 2024 will be included. An ERCP will be considered to have been performed when an endoscope is introduced to access the duodenal papilla.

These included patients must meet all of the following criteria:

• Over 18 years of age
• Signed informed consent.

Exclusion Criteria:

• Under 18 years of age
• Unavailability of informed consent
• Impossibility of follow-up.

Patients with biliopancreatic pathology for whom ERCP is performed in hospitals in Spain.

Data obtained through this study may be provided to qualified researchers with academic interest in ERCP and biliopancreatic diseases. Data or samples shared will be coded, with no PHI included. Approval of the request and execution of all applicable agreements (i.e. a material transfer agreement) are prerequisites to the sharing of data with the requesting party.

Data requests can be submitted starting 10 months after article publication and the data will be made accessible for up to 24 months. Extensions will be considered on a case-by-case basis.

Beginning 10 months and ending 2 years after the publication of results.

Access to trial IPD can be requested by qualified researchers engaging in independent scientific research, and will be provided following review and approval of a research proposal and Statistical Analysis Plan and execution of a Data Sharing Agreement.