Predictors for external and internal pancreatic fistulas after pancreatic necrosis

Abstract

Aim. To analyze the outcomes of pancreatic necrosis depending on the depth and localization of damage to the pancreatic tissue, to determine the main risk factors for the development of external and internal pancreatic fistulas. Materials and methods. The analysis of long-term results of treatment of pancreatic necrosis in 81 patients was carried out: 53 patients were treated at the stage of acute pancreatitis in our clinic, 28 - in other medical institutions. The algorithm of the survey included a CT scan with contrast enhancement, fistulography, MRI-pancreatocholangiography and/or endoscopic retrograde cholangiopancreatography. The influence of various factors on the development of pseudocysts and pancreatic fistulas was estimated using the Spearman correlation coefficient. Results. Signs of damage to the pancreatic duct were detected in 19 (36%) of 53 patients: 9 were diagnosed with pseudocysts, 10 had external pancreatic fistulas. The daily flow rate of pancreatic juice (α-amylase activity >20950 u/l) was 300-350 ml. Interventions (minimally invasive, open surgery) required 10 patients (52.6%). The correlation coefficient of external pancreatic fistulas with the depth of pancreatic necrosis was 0.46 (p = 0.00005), the CT severity index according to Balthazar - 0.05 (p = 0.63), the localization of necrosis in the neck - 0.31 (p = 0.006), the amount of drainage discharge - 0.55 (p = 0.000001), the activity of α-amylase fluid - 0.53 (p = 0.000002). There was a significant positive correlation of mediastinal pancreatogenic cysts with pseudocysts located on the posterior surface of the pancreas (r = 0.7; p = 0.003), pleural effusion with high activity of α-amylase (r = 0.87, p = 0.0005) and alcoholic etiology of acute pancreatitis (r = 0.75, p = 0.002). Conclusion. Predictors of resistant to conservative treatment external pancreatic fistulas are deep necrosis, especially in the area of the neck of the pancreas, the discharge flow rate through the drainage is more than 150 ml with an α-amylase activity of more than 1000 u/l. A risk factor for the development of internal pancreatic fistulas with penetration into the mediastinum is the localization of pseudocysts on the posterior surface of the pancreas in the body and tail area.