Risk factors and outcomes of postoperative pancreatic fistula after pancreatico-duodenectomy: an audit of 532 consecutive cases

PF is the most challenging complication after PD. Because it was associated with substantial mortality and morbidity, some authors even defined it as an “Achilles heel” of PD [6]. Our results demonstrate that the incidence of PF after PD was about 12.0%, which appears to be comparable to the PF rate of 9–14% reported in other specialized centers [14-17].

The formation of PF is associated with many variables involving demographic, preoperative, intraoperative and pathological factors. Previous studies had reported that pancreaticogastrostomy was associated with significantly lower pancreatic fistula rate than pancreaticojejunostomy. Pancreaticogastrostomy was more efficient than pancreatico-jejunostomy in reducing the incidence of postoperative pancreatic fistula [18-23]. In our institution, we have not performed pancreaticogastrostomy after PD so far. There is still a controversy in the relationship between preoperative biliary drainage and the incidence of PF. A study from Hopkins suggested that preoperative stent was associated with high incidence of postoperative pancreatic fistula [24]. Schmidt et al. also showed that those patients who had preoperative percutaneous transhepatic biliary (PTB) stent showed an increased risk of PF formation [6]. However, Aranha et al. found that no difference in the incidence of PF versus no-PF in those patients having ERCP or PTC and an increase in PF in those patients who did not have preoperative stents compared with those patients who did [8]. Lin et al. indicated that no difference in the incidence of PF versus no-PF in those patients having preoperative stent (either endoscopic or PBD) [14]. Our results also showed that there was no relationship between preoperative biliary drainage and postoperative PF.

As expected, increased intraoperative blood loss appeared to be an important risk factor of PF. Yeh et al. demonstrated increased intraoperative blood loss was an independent risk factor for PF after PD by univariate and multivariate analysis [25]. The factors which might increase blood loss during operation included a more advanced stage of the disease such as portal vein invasion or superior mesenteric vein, adhesions due to prior operations, jaundice-associated coagulopathy, obesity, and concurrent pancreatitis [25]. In our study, Intraoperative blood loss exceeding 500 ml occurred in 39.7% (211 of 532 patients) of patients, and of those, 17.5% patients (37/211) developed PF, which was significantly higher than patients with blood loss less than 500 ml (28/321, 8.7%). Again, our results showed blood loss ≥ 500 ml (hazard ratio [HR] = 2.281; 95% confidence interval [CI] 1.334-3.901; P = .003) was an independent risk factor for PF after PD. Kawai et al. showed that the preoperative CT image-assessed ligation of inferior pancreaticoduodenal artery (IPDA) method (CLIP) was a useful and reliable operative technique for reducing intraoperative bleeding in PD [26]. Ishizaki et al. reported early ligation of the inferior pancreatoduodenal artery (IPDA) not only reduced intraoperative blood loss during PD but also alleviated postoperative morbidity and mortality [27]. Therefore, IPDA method was suggested to decrease intraoperative bleeding.

Type of pancreaticojejunostomy anastomosis has also been cited as a predictor of PF after PD. Berger et al. reported considerably fewer fistulas with invagination compared with duct to mucosapancreaticojejunostomy after pancreaticoduodenectomy by a randomized, prospective, dual-institution trial [28]. However, Schmidt et al. and Bartoli et al. reported that lowest incidence of PF in patients who had a duct to mucous anastomosis than other anastomoses [6,29]. We also found that the lowest incidence of PF in patients who had a duct to mucous anastomosis (4.9%) versus a traditional 2-layers pancreaticojejunostomy (10.9%) or an invaginated pancreaticojejunostomy (21.6%) (P < .001). Since the diameter of major pancreatic duct played an important role in selection of PJ types, some studies have concluded that major pancreatic duct diameter was also an independent risk factor of PF after PD [4,23]. Generally, the narrowed pancreatic duct diameter is not only more challenging to reconstruct, but also more likely to either occlude or dehisce. In our study, we found that PF in patients who had pancreatic duct diameter > 3 mm (6.4%) was significantly lower than those who had pancreatic duct diameter ≤ 3 mm (17.3%) (P < .001). Soft pancreatic tissue has been regarded as a potent contributor for PF formation [4,7,14], while it had no effect on PF in our study. Based on our results and literatures, we think we should try to adopt duct to mucous anastomosis when the pancreatic duct diameter > 3 mm. If the pancreatic duct diameter measured 3 mm or less, we can expand the pancreatic duct by placing a fine stay suture in the middle of the anterior wall of the pancreatic duct as described by Hatori [30] and performed pancreaticojejunostomy with duct-to-mucosa anastomosis without a stent tube [31].

PF is associated with a greater many of other complications and prolonged hospital stay [6,8,14,28]. In our study, it was found to be associated with mortality, abdominal bleeding, bile leakage, intraabdominal abscess, pneumonia, reoperations and long hospital stay. Other complications including gastrointestinal bleeding, delayed gastric emptying, wound infection, deep venous thrombosis (DVT) and chyle leak were not significant when the PF group was compared with the no PF group.