Patients characteristic
All the patients administrated in The First Affiliated Hospital to Henan University of Science and Technology during January 2017 to August 2019 who needed PD for malignant tumor. All the operations were completed by the same team. This was a retrospectively designed trial. This clinical trial was approved by the ethics committee of The First Affiliated Hospital to Henan University of Science and Technology.
According to the procedure of PJ, we divide the patients into two groups: Custom D-M group and invaginated D-M group. All patients included were aged 18 to 80 years old; the American society of anesthesiologists (ASA) classification should be at 1 to 3; the diagnosis was approved by pathology; enhanced CT scan and MRCP were routinely performed. All patients included should be proved by enhanced CT or / and enhanced MR of no tumor invasion of vessels. All pancreatic duct size was dilated more than 2 mm. In case of bias control, we matched some factors. The matched factors were age (± 5 y), sex, pancreatic texture and pancreatic duct size (± 1 mm). Those factors were reported as important risk factors of pancreatic leakage[9]. All the characteristics of the two groups were list in the table 1.
Operation procedure
All the operations were performed under general anesthesia. Pancreaticoduodenectomy was performed with local lymph nodes dissection. Jejunal limb was brought up through retrocolic root. After end to side PJ, cholangiojejunostomy was performed with 4-0 knotless suture (Stratafix, Ethicon) by a running suture about 8 cm distal to the PJ. Gastrojejunostomy was performed by a circular stapler (Panther) about 50 cm distal to cholangiojejunostomy. Additional jejunojejunostomy was performed by 4-0 knotless suture (Stratafix, Ethicon) about 10 cm distal to gastrojejunostomy. The difference between the two groups was the procedure of PJ. Custom D-M group was performed as modified Blumgart anastomoses descript by Shoji Kawakatsu [8]. Invaginated D-M group was performed as follow: a 3-0 polypropylene suture (Prolene, Ethicon) was employed to finish the anastomosis. The first stitch transfixed pancreas from anterior to posterior at about 1 cm from the superior board of pancreatic neck where located 1.5 cm distal to the pancreatic cutting end. The needle gone through the seromuscular of the jejunum limb at the antimesenteric margin. Then, the first knot was made anteriorily shown as figure 1. The second stitch was about 1 cm departed from the first knot which was also 1.5 cm distal to the pancreatic cutting end. The second stitch transfixed the pancreatic neck from anterior to posterior (figure 2 ①), then, it gone through the seromuscular layer of the jejunum 1 cm from the first stitch (figure 2 ①). The needle gone through the pancreas from posterior to anterior about 1 cm distal to the pancreatic cutting end (figure 2 ②), then, it gone through the seromuscular layer of the jejunum 1 cm from the first knot (figure 2 ③). The suture was strengthened, and duplicated the second suture (figure 2 ④). When the suture reached to the superior of pancreatic duct, it suspended. Then, duct to mucosa anastomosis was performed as custom D-M by 4-0 polyglactin suture (Vicryl Plus, Ethicon). After duct to mucosa anastomosis, pancreaticojejunostomy continued as descript above until to the inferior board of pancreatic neck. The last stitch was just like the first one. When the needle gone through the pancreatic neck about 1.5 cm distal to the pancreatic cutting end from anterior to posterior, it gone through the seromuscular layer of the jejunum limb; then, the second knot was made (figure 3). Before making the knot, what was emphasized was to strengthen every stitch moderately. Others should be emphasized were following: the jejunal serosa was destructed by electrocoagulation to accelerate healing of pancreatic cutting end and jejunum limb as descript by Hong [7]; pancreatic duct stent should be placed when duct to mucosa anastomosis; pancreatic duct should be separated about 2 mm when transaction of pancreas, this separation facilitated the invigation of pancreatic duct to mucosa of jejunum. Drainage tubes should be placed around cholangiojejunostomy and pancreaticojejunostomy with additional pelvic drainage when necessary. Peritoneal lavage with distilled water was emphasized before abdominal closure.
Perioperative management
Percutaneous transhepatic cholangial drainage (PTCD) were perform when cholangitis existed. Anemia correction should be performed routinely to 90 g/L or above. Serum albumin should be maintained at normal level. Breathing exercises were performed at least 2 days before operation. The pressure of O2 and CO2 should be at normal level by arterial blood gas analysis.
Postoperative management was performed according to the principle of Enhanced Recovery after Surgery (ERAS) [14]. Gastric tube was removed after operation when the patient recovered from anesthesia. Abdominal drainage amylase test was routinely performed at 1, 3, 7 day postoperatively with additional test when pancreatic leakage was suspected. Abdominal drainage tubes were removed when the drainage was less than 20 ml/d, which should be retained at least 7 days postoperatively. Abdominal CT scan was routinely performed to ensure no ascites before drainage removal. Discharged criteria was set as recovery to semifluid diet without symptomatic pancreatic leakage or biliary leakage at least 7 days postoperatively.
Definition
Primary endpoint was pancreatic leakage. Pancreatic leakage was detected following the International Study Group of Pancreatic Fistula (ISGPF) [15]. The severity of pancreatic leakage was classified according to the criteria of ISGPF. Bleeding means hematochezia or haematemesis or blood drainage from abdominal cavity. Mortality was limited to 30 days postoperatively.
Statistical analysis
SPSS 16.0 was used to analyze the data. The measurement data, including age, BMI, pancreatic duct size, operation time, pancreaticojejunostomy time, blood loss, and postoperative hospitalization, were compared with t tests. The numerical data, such as sex, American Society of Anesthesiologists (ASA) classification, pancreas texture, tumor origin, number of required transfusion, pancreatic leakage, bleeding, biliary leakage, pneumonia, and thrombosis, were compared with chi square tests. P < 0.05 was considered to be significant.