Abstract:

Objective This study tried to analyze the clinical effect of double plastic biliary stent implan⁃ tation combined with ursodeoxycholic acid（UDCA）in the treatment of difficult large stone（≥ 15 mm）in common bile duct（CBD）. Methods Sixty⁃three patients with difficult CBD large stone from January 2018 to December 2019 in our hospital were enrolled，All the patients were placed double plastic biliary stents by endoscopic retrograde cholangiopancreatography（ERCP）. Thirty ⁃two patients in the observation group received oral administration of UDCA 15 mg/（kg · d）for 3 months after ERCP while the other 31 patients without UDCA were included in the control group. Stents in each patient were pulled out 3 months after the first ERCP. The incidence of abdominal pain or distention，abnormal liver function，cholangitis before second ERCP and stents obstruction，diameter change of the largest CBD stone and success rate of stone removal during second ERCP were compared between the two groups. Results ERCP was successful in all patients and no serious complications（such as gastrointestinal bleeding，perforation，and severe acute pancreatitis）occurred during two operations. The incidence of abdominal pain or distension，liver dysfunction，cholangitis before second ERCP and stents obstruction found in second ERCP in the observation group was 6.3%（2/32），18.8%（6/32），3.1%（1/32）and 15.6%（5/32）respectively， which was significantly lower than the according index of 25.8%（8/31），45.2%（14/31），22.6%（7/31）and 38.7% （12/31）in the control group. The difference between the two groups was statistically significant （χ2 = 4.510， 5.069，5.376，4.259；P = 0.043，0.024，0.026，0.039）. In the observation group，the median value of the diameter of the largest CBD stone was 17 mm and 12 mm respectively during two ERCP operations，while in the control group was 17 mm and 15 mm. The diameter of the largest CBD stone in both groups were significantly reduced in the second ERCP compared with first ERCP and the differences were statistically significant（Z = 4.659，4.736；P < 0.001）. The effect of the mean stone diameter reduction was more significant in the observation group（Z = 3.883，P < 0.001）. The success rate of stone removal in second ERCP was 90.6%（29/32）in the observation group and 71.0% （22/31）in the control group with statistically significant difference（χ2 = 3.946，P = 0.047）. Conclusions In patients with difficultly large CBD stone，double biliary plastic stents combined with UDCA could more effectively reduce the incidence of abdominal pain or distention，abnormal liver function，cholangitis and stents obstruction before secondary ERCP. It also could reduce the diameter of the largest CBD stone and thus improve the success rate of stone extraction.

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