Analysis of risk factors of postoperative pancreatic fistula after pancreaticoduodenectomy

Objective To investigate the risk factors of postoperative pancreatic fistula after pancreatico-duodenectomy (PD). Methods The retrospective case-control study was adopted. The clinicopathological data of 196 patients with PD who were admitted to First Affiliated Hospital of Dalian Medical University from September 2014 to July 2016 were collected. All the patients underwent PD. Observation indicators: (1) intra- and post-operative situations; (2) follow-up; (3) analysis of risk factors of pancreatic fistula after PD. All patients were followed up by outpatient examination and telephone interview to detect pancreatic fistula and peritoneal fluid collection up to March 2017. Measurement data with normal distribution were represented as ±s and comparison between groups was analyzed by t test. Measurement data with skewed distribution were represented as median (range). Count data and univariate analysis were done using the chi-square test. Logistic regression model was used for multivariate analysis. Results (1) Intra- and post-operative situations: all the 196 patients underwent surgeries successfully. The operation time, volume of intraoperative blood loss, number of intraoperative blood transfusion and non intraoperative blood transfusion were (439±136)minutes, (686±280)mL, 45 and 151 cases, respectively. Time to initial anal exsufflation, time of initial defecation and time for first diet after operation were (4.1±2.1)days, (5.1±2.9)days and (3.1±2.0)days. Of 76 patients, the content of diastase in the intraperitoneal drainage was 614 U/L (31-30 215 U/L) at postoperative day 1 and level of serum procalciton in was (0.7±0.4)ng/mL at postoperative day 3. Time for drainage tube removal of 196 patients was (14.6±7.1)days. Fifty four of 196 patients with postoperative complications were improved by symptomatic treatment, including 15 with intestinal obstruction, 12 with delayed gastric emptying, 11 with abdominal infection, 9 with incision infection, 7 with bleeding. Duration of postoperative hospital stay was (17.1±4.2)days. Results of pathological diagnosis of 196 patients showed 121 cases of pancreatic cancer, 50 of intraductal papillary mucinous tumors of the pancreas, 7 ampullary carcinoma, 15 of carcinoma of the lower end of the bile duct, and 3 of duodenum cancer. Pancreatic findings: pancreatic texture: 95 cases were with soft pancreas and 101 with hard pancreas. Diameter of main pancreatic duct duct: 101 cases had diameter of pancreatic duct duct ≥3 mm and 95 cases <3 mm. (2)Follow-up: all the 196 patients were followed up for 4-30 months, with a median follow-up time of 18 months. During follow-up time, the grade B /or C pancreatic fistula occurred in 37 cases. Of 16 patients with pancreatic fistula-ralated ascites, 10 had readmission and were improved by symptomatic treatment. (3) Analysis of risk factors of pancreatic fistula after PD: the results of univariate analysis showed that the content of diastase in the intraperitoneal drainage at postoperative day 1, level of serum procalcitonin at postoperative day 3 and pancreatic texture were related factors affecting the pancreatic fistula after PD (χ2=6.569, 5.902, 13.517, P<0.05). The results of multivariate analysis showed that the content of diastase in the intraperitoneal drainage at postoperative day 1 ≥600 U/L was an independent risk factor affecting the pancreatic fistula after PD (OR=9.135, 95% confidence interval: 2.247-37.130, P<0.05). Conclusion The content of diastase in the intraperitoneal drainage at postoperative day 1 ≥600 U/L is an independent risk factor affecting the pancreatic fistula after PD. Key words: Pancreatic neoplasms; Biliary neoplasms; Pancreatic fistula; Pancreatic fibrosis; Pancreaticoduodenectomy