| Research backgroundEndoscopic retrograde cholangiopancreatography (ERCP) is a minimally invasive interventional endoscopy for disease diagnosis and treatment. Since the introduction of endoscopiesphineterotomy, ERCP-related technologies rapidly became popular. After nearly 40 years of development, ERCP has become an indispensable diagnostic tool and treatment for biliopancreatic diseases.Despite being a model of a minimally invasive technique, ERCP is a complicated and high-risk operation. Some complications cannot be avoided completely. Post-ERCP pancreatitis (PEP) is the most common complication, accounting for approximately half of all ERCP complications. With the idea renewal, standardized technological process, and equipment innovation, the incidence rate of PEP has decreased significantly. Latest data show that the incidence of PEP is approximately 3.5% in the nonselective population and 10% to 30% in the high-risk population. Although 90% of these cases are mild-to-moderate pancreatitis,10% of these cases will still develop into severe acute pancreatitis (SAP). SAP is extremely dangerous with many complications, which may result in pancreatic necrosis, multiple organ failure, or even death.PEP is caused by many factors, including patient-related and procedure-related factors. Despite the gradual standardization of indications and operation procedures, PEP still exists. Doctors performing endoscopy have been seeking for a method and drug to prevent and reduce PEP. Randomized controlled trials (RCTs) and meta-analysis have demonstrated that selective pancreatic duct stenting can reduce the incidence rate of PEP in the high-risk population (odds ratio [OR],0.44; 95% confidence interval [CI], 0.24-0.81), and the absolute risk is reduced by 12.0%(95% CI,3.0-21.0). Nonsteroidal anti-inflammatory drugs are the only effective pharmaceutical preparations that prevent PEP. Moreover, a multicenter prospective randomized controlled study published in the New England Journal of Medicine in 2012 confirmed that indomethacin suppository can significantly reduce the incidence of PEP in the high-risk population; thus, its clinical applications gradually increased. Indomethacin suppository is recommended for the low-risk population by the European Society of Gastrointestinal Endoscopy. Compared with selective pancreatic stenting, indomethacin suppository is simple and feasible and can be conducted in large and small endoscopy centers. The basis of the doctors performing endoscopy in selecting between these two approaches in clinical practice remains a question. In addition, whether indomethacin can be completely replaced by selective pancreatic duct stenting remains unknown. Given the limitations of the clinical trial design and included cases, a simple controlled clinical trial for selective pancreatic duct stenting and indomethacin suppository should be performed. The prospective randomized controlled experiment is the best method. However, it cannot be strictly implemented because of ethical limitations.Propensity score matching (PSM) is a statistical method used to process and balance biased and confounding factors between experimental and control groups to achieve a more reasonable comparison. According to statisticians and mathematicians, the PSM can achieve a statistical efficiency similar to that of RCTs. Several clinical trials, which do not obtain randomized controlled data or violate the scientific research ethics, can adopt PSM to process data and eliminate the interference factors between groups so that an accurate conclusion can be drawn. Thus, this study aims (1) to balance the bias between retrospective data by using the PSM method, as well as to compare the effects of selective pancreatic duct stenting and indomethacin suppository in PEP prevention, and (2) to investigate the optimal indication of pancreatic duct stenting in PEP prevention.Part 1Comparison of the efficacy of pancreatic duct stenting and indomethacin suppository in PEP prevention:a PSM studyObjectiveThis study aims to compare selective pancreatic duct stenting and indomethacin suppository and determine which is the more superior clinical strategy for preventing PEP in high-risk populations.MethodERCP patients treated in the Endoscopy Treatment Department of Shandong University affiliated to Shandong Provincial Qianfoshan Hospital from June 2008 to June 2015 served as research subjects. These patients were included in the high-risk population undergoing selective pancreatic duct stenting or indomethacin suppository to prevent PEP. Demographic data, PEP risk factor, and other clinical baseline data were collected. The incidence rates of PEP and moderate-to-severe PEP served as the main observation indicators. Gender, age, and PEP risk factors served as references in the selective pancreatic duct stenting group. Propensity score was calculated using multifactor logistic regression. The patients with approximate scores were randomly matched with those in the indomethacin suppository group by using the PSM method and paired with those in the pancreatic duct stenting group at a 1:1 ratio. The total incidence rates of PEP in the two groups and the incidence rate of moderate-to-severe PEP were statistically analyzed. In addition, the incidence rates of selective pancreatic duct stenting and indomethacin suppository complications were statistically analyzed.Results1. A total of 623 dialysis patients, including 478 cases (76.7%) in the indomethacin suppository group and 145 cases (23.3%) in the selective pancreatic duct stenting group, were included in this study. The baseline data of these two groups were compared before and after PSM. A significant difference was observed between the patients in terms of intubation time of>10 min and intraductal ultrasound before matching (p<0.05). A total of 145 pairs of patients were matched using PSM. The baseline data, including age, gender, and PEP risk factors, showed no significant difference (p>0.05). Among the 623 cases,50 cases exhibited PEP and the total incidence rate was 8%. Before matching, the incidence rates of PEP in the selective pancreatic duct stenting group and indomethacin suppository group were 6.9% (10/145) and 8.4%(40/478), respectively, whereas the incidence rates of moderate-to-severe PEP were 2.8%(5/145) and 4.0%(19/478), respectively (Fig.1A). However, these differences were not statistically significant (p> 0.05). After matching, the incidence rates of PEP in the selective pancreatic duct stenting group and indomethacin suppository group were 6.9%(10/145) and 15.2%(22/145), respectively, whereas the incidence rates of moderate-to-severe PEP were 2.8%(5/145) and 9.7%(14/145), respectively (Fig.1B). These differences were statistically significant (p< 0.05). Five cases exhibited severe pancreatitis, and two of these cases underwent selective pancreatic duct stenting, whereas the three other cases received indomethacin suppository. The patients did not suffer from pancreatic necrosis as revealed by CT scan, and they all recovered after conservative treatment.2. Complication analysis:The self-shedding rate of the selective pancreatic duct stenting was 96.6%(140/145), and the average time was 2.4 days (0 day to 6 days). In addition, no major complication was observed in the two groups, and abdominal pain was the most common complaint. The incidence rates were 20%(29/145) and 16.6% (24/145), and the difference was not statistically significant (p> 0.05).ConclusionsAlthough indomethacin suppository is an economical and simple approach, selective pancreatic duct stenting is the preferred strategy for preventing PEP among high-risk patients.Part 2Optimum indications of pancreatic duct stenting to prevent PEP ObjectiveThis study aims to investigate the optimum indications of pancreatic duct stenting to prevent PEP in high-risk populations.Method Subgroup analysis on the high-risk factors of PEP, including age, gender, sphincter of Oddi dysfunction (SOD), PEP history, intubation time of>10 min, precut papillary sphincter, transpancreatic sphincterotomy, guide wire entering the pancreatic duct many times, intracavity contrast agent injection, intracavity ultrasound, and endoscopic ampulla resection delamination, was performed. After data fractionation, the OR of PEP selective pancreatic stenting versus indomethacin suppository was calculated by logistic analysis. The group demonstrating the benefits of the treatment was analyzed to determine the optimal indications of pancreatic duct stenting to prevent PEP.ResultsStatistical analyses of all subgroups showed that the ORs of PEP were as follows: (1) Age:<40 years old:OR,0.62; 95% CI,0.26-1.56; and p=0.19;?40 years old: OR,0.73; 95% CI,0.34-1.65; p=0.23.(2) Gender:male:OR,0.86; 95% CI, 0.36-1.98; and p=0.09; female:OR,0.57; 95% CI,0.13-1.78; and p=0.11. (3)With SOD:OR,0.54; 95% CI,0.16-1.27; and p=0.06. (4) Without SOD:OR,0.87; 95% CI,0.38-1.89; and p=0.13. (5) With PEP history:OR,0.56; 95% CI,0.29-1.49; and p=0.08; without PEP history:OR,0.98; 95% CI,0.31-2.18;and p=0.12. (6) Intubation time of>10 min:OR,0.32; 95% CI,0.11-1.24; and p=0.03;intubation time of?10 min:OR,0.87; 95% CI,0.23-1.89; and p=0.07.(7) Precut papillary sphincter:OR,0.23; 95% CI, data; p=0.01;without precut papillary sphincter:OR, 0.79;95% CI,0.27-1.99; and p=0.09. (8) Transpancreatic papillary sphincterotomy incision:OR,0.26; 95% CI,0.06-2.01;and p=0.02;no transpancreatic papillary sphincterotomy incision:OR,0.89,95% CI,0.33-2.19;and p=0.23. (9) Guide wire entering the pancreatic duct many times:OR,0.24; 95% CI,0.01-1.09;and p=0.01; guide wire did not enter the pancreatic duct:OR,0.88; 95% CI,0.24-2.89; and p= 0.33.(10) Contrast agent injection into the pancreatic duct:OR,0.65; 95% CI, 0.23-1.79;and p=0.13;without contrast agent injection into the pancreatic duct:OR, 0.79; 95% CI,0.25-1.90; and p=0.08. (11) Intracavity ultrasound:OR,0.66; 95% CI, 0.13-1.98;and p=0.07; without intracavity ultrasound:OR,0.78; 95% CI,0.32-2.19; and p=0.09. (12) Endoscopic ampulla resection:OR,0.21; 95% CI,0.03-1.09; and p =0.01; without endoscopic ampulla resection:OR,0.85; 95% CI,0.43-2.45; and p= 0.19.ConclusionThe results of the subgroup analysis show that pancreatic duct stenting is more beneficial to patients with an intubation time of>10 min, precut papillary sphincter, precut transpancreatic papillary sphincter, guide wire entering the pancreatic duct many times, and endoscopic ampulla resection. These populations were recommended to undergo routine pancreatic stenting to prevent PEP. |
PDF Full Text Request