Complications of temporary pancreatic stent insertion for pancreaticojejunal anastomosis during pancreaticoduodenectomy

USE of Biodegradable STENTS in Pancreaticoduodenectomy: Initial Experience

Background. Plastic stents have been used to avoid postoperative pancreatic fistula (POPF) following Whipple's Pancreaticoduodenectomy (WPD), but they may cause some stent-related complications. Biodegradable stents have been recently introduced and might be a safe alternative. Here we present our initial experience with their use. Methods. Between March 1, 2020, and September 30, 2020, ten (10) consecutive patients underwent WPD. They all had conventional two-layer pancreaticojejunostomy with the placement of an internal biodegradable stent. They were assessed for technical feasibility, pancreatic leak, and stent-related complications. Results. The use of biodegradable stents was technically feasible in all patients, despite some difficulties in insertion due to stent stiffness and design. After a median follow-up period of 124 days, none of the patients suffered POPF. One patient had a biochemical pancreatic leak with no clinical significance. The median hospital stay was 7 days, and there were no stent-related complications. Conclusion. Biodegradable stents are technically feasible and safe in WPD with good short-term outcomes. They might provide a better alternative to plastic stents and their potential complications. Larger long-term studies are needed to validate efficacy and safety. Few modifications of the stent's design might be needed to facilitate use in open surgery.

Novel biodegradable internal stent as a mitigation strategy in high-risk pancreaticojejunostomy: technical notes and preliminary results

Clinically relevant postoperative pancreatic fistula (CR-POPF) is the most feared complication after pancreaticoduodenectomy (PD), as it can lead to extremely poor outcomes. We herein report the preliminary results of an anastomotic technique based on the use of a novel internal biodegradable stent (IBS) to mitigate POPF sequelae. Between October 2020 and May 2021, all patients undergoing PD with high-risk pancreatic anastomosis received a pancreato-jejunal (PJ) anastomosis with an Archimedes™ IBS placement. Fifteen patients comprised our study cohort. In 11 cases, a 2-mm Archimedes™ stent was used, and in the remaining four patients, a 2.6-mm stent was used. Overall postoperative complications occurred in eight patients, with four cases being severe. Two patients developed CR-POPF, with one of them dying. In our small preliminary series, PJ anastomosis with an Archimedes™ IBS showed encouraging results in terms of CR-POPF incidence. Further studies are needed to confirm these findings.

Preventive effect of biodegradable stents on biliary stricture and fibrosis after biliary anastomosis in a porcine model

Purpose

The current drain tubes for preventing surgically biliary anastomotic stricture are not naturally and easily removed. If a drain tube using biodegradable material is easily available and the degradation time of the tube is well controlled, surgical anastomotic stricture and fibrosis could be prevented. The aim of this animal study was to evaluate the preventive effect of novel biodegradable stents (BS) on biliary stricture and fibrosis after duct-to-duct (DD) biliary anastomosis.

Methods

Ten mini-pigs were allocated to the control group (n = 5) and or the stent group (n = 5). The common bile duct was exposed through surgical laparotomy and then resected transversely. In the stent group, a 4-mm or 6-mm polydioxanone/magnesium sheath-core BS was inserted according to the width of the bile duct, followed by DD biliary anastomosis. In the control group, DD biliary anastomosis was performed without BS insertion.

Results

In the stent group, stents were observed without deformity for up to 4 weeks in all animals. Eight weeks later, histopathologic examination revealed that the common bile duct of the anastomosis site was relatively narrower in circumference in the control group compared to the stent group. The degree of fibrosis in the control group was more marked than in the stent group (3.84 mm vs. 0.68 mm, respectively; P < 0.05).

Conclusion

Our study showed that novel BS maintained their original shape and radial force for an adequate time and then disappeared without adverse events. The BS could prevent postoperative complications and strictures after DD biliary anastomosis.

Propensity score-matched analysis of internal stent vs external stent for pancreatojejunostomy during pancreaticoduodenectomy: Japanese-Korean cooperative project

BACKGROUND

Several studies comparing internal and external stents have been conducted with the aim of reducing pancreatic fistula after PD. There is still no consensus, however, on the appropriate use of pancreatic stents for prevention of pancreatic fistula. This multicenter large cohort study aims to evaluate whether internal or external pancreatic stents are more effective in reduction of clinically relevant pancreatic fistula after pancreaticoduodenectomy (PD).

METHODS

We reviewed 3149 patients (internal stent n = 1,311, external stent n = 1838) who underwent PD at 20 institutions in Japan and Korea between 2007 and 2013. Propensity score matched analysis was used to minimize bias from nonrandomized treatment assignment. The primary endpoint was the incidence of clinically relevant pancreatic fistula. This study was registered on the UMIN Clinical Trials Registry (UMIN000032402).

RESULTS

After propensity score matched analysis, clinically relevant pancreatic fistula occurred in more patients in the external stents group (280 patients, 28.7%) than in patients in the internal stents group (126 patients, 12.9%) (OR 2.713 [95% CI, 2.139-3.455]; P < 0.001). In subset analysis of a high-risk group with soft pancreas and no dilatation of the pancreatic duct, clinically relevant pancreatic fistula occurred in 90 patients (18.8%) in internal stents group and 183 patients (35.4%) in external stents group. External stents were significantly associated with increased risk for clinically relevant pancreatic fistula (OR 2.366 [95% CI, 1.753-3.209]; P < 0.001).

CONCLUSION

Propensity score matched analysis showed that, regarding clinically relevant pancreatic fistula after PD, internal stents are safer than external stents for pancreaticojejunostomy.

A Novel Biodegradable Tubular Stent Prevents Pancreaticojejunal Anastomotic Stricture

Stricture of pancreatic-enteric anastomoses is a major late complication of a pancreaticoduodenectomy for the treatment of a periampullary tumor and can lead to exocrine and endocrine insufficiency such as malnutrition and diabetes mellitus. We investigated the safety and efficacy of a biodegradable tubular stent (BTS) for preventing a pancreaticojejunostomy (PJ) anastomotic stricture in both a rat and porcine model. The BTS was manufactured using a terpolymer comprising poly p-dioxanone, trimethylene carbonate, and glycolide. A cohort of 42 rats was randomized into 7 groups of 6 animals each after BTS placement into the duodenum for the biodegradation assay. A total of 12 pigs were randomized equally into a control and BTS placement group. The effectiveness of the BTS was assessed by comparing radiologic images with histologic results. Surgical procedures and/or BTS placements were technically successful in all animals. The median mass losses of the removed BTS samples from the rat duodenum were 2.1, 6.8, 11.2, 19.4, 26.1, and 56.8% at 1, 2, 3, 4, 6, and 8 weeks, respectively. The BTS had completely degraded at 12 weeks in the rats. In the porcine PJ model, the mean luminal diameter and area of the pancreatic duct in the control group was significantly larger than in the BTS group (all p < 0.05). BTS placement thus appears to be safe and effective procedure for the prevention of PJ anastomotic stricture. These devices have the potential to be used as a temporary stent placement to treat pancreatic-enteric anastomoses, but further investigations are required for optimization in human.

Assessing spontaneous passage of prophylactic pancreatic duct stents by X-ray: is a radiology report adequate?

Background:

Pancreatic duct stents are frequently placed for prophylaxis of post-endoscopic retrograde cholangiopancreatography pancreatitis. Because of concern for possible secondary ductal changes from a retained stent, these stents need to be monitored and removed if retained. Usually an abdominal X-ray is performed to assess retained stent, and if present, an esophagogastroduodenoscopy is performed to remove the stent. Limited data is published on false-negative radiology reports for spontaneous passage of stents.

Methods:

Using an Institutional Review Board–approved stent log, a retrospective chart review of all pancreatic duct stents placed at our institution from 2008 to 2014 was performed.

Results:

A total of 856 pancreatic duct stents were placed during the study period. Of these, 435 (50.8%) were prophylactic stents and 421 (49.2%) were therapeutic. Complete follow-up data were available in 426 (97.9%) patients with prophylactic stents. Six patients (1.4%) were lost to follow up and three (0.7%) expired prior to removal. In all, 283 (66%) had follow-up imaging, with 167 (39.2%) having the official radiology read with no retained pancreatic duct stent in place. Eight of these cases were “false-negative” radiology interpretation (4.8% of cases read as “no stent,” NNH = 20). The stent was found either by review of image by an endoscopist or incidental stent discovery during a follow-up procedure.

Conclusion:

Radiologist interpretation of abdominal X-rays to assess spontaneous passage of prophylactic pancreatic ducts stents resulted in a false-negative interpretation in approximately 5% of cases. Independent review of the images by the endoscopist may be beneficial given unfamiliarity of these stents by radiologists.

Gastroenterology and pancreatic adenocarcinoma: what the radiologist needs to know

In this article, we review the information that radiologists need to know regarding the endoscopic approach to the diagnosis and management of pancreatic cancer. This includes a review of the indications, techniques, and complications of endoscopic ultrasound. We also review information regarding endoscopic retrograde cholangiopancreatography, including the various biliary drainage techniques and the use of endoscopic palliation for patients with pancreatic cancer.

Successful removal of an internal pancreatic stent that migrated into the bile duct using double-balloon enteroscopy after pancreaticoduodenectomy

PURPOSE

Internal stents used during pancreaticoduodenectomy (PD) are generally spontaneously passed through the rectum by defecation. However, we encountered six patients with internal stents that migrated into the bile duct after PD. We herein report the outcomes of these six patients and the usefulness of double-balloon enteroscopy (DBE) for removal of such stents from the bile duct.

METHODS

An internal stent was placed across pancreaticojejunostomy in 416 (68.8%) of 605 consecutive patients undergoing PD between 2005 and 2015. This study evaluated the characteristics and outcomes of the six patients whose internal stent migrated into the bile duct.

RESULTS

Migration of an internal stent into the bile duct was found during follow-up computed tomography (CT) in 6 (1.4%) of 416 patients who had an internal stent placed during PD. Three patients developed stent-induced cholangitis, and two had bile duct stones. Excluding one patient whose internal stent spontaneously slipped out and disappeared from the bile duct, all patients underwent successful removal of a stent from the bile duct by a single instance of biliary intervention involving DBE.

CONCLUSIONS

Removal of a stent from the bile duct using DBE is a feasible and useful procedure that should be considered if an internal stent is detected during follow-up CT after PD.

Pancreatoduodenectomy (PD) and postoperative pancreatic fistula (POPF): A systematic review and analysis of the POPF-related mortality rate in 60,739 patients retrieved from the English literature published between 1990 and 2015

BACKGROUND

Pancreatoduodenectomy (PD) is one of the most technically demanding operations challenging surgeons, and a postoperative pancreatic fistula (POPF) can complicate an otherwise uneventful postoperative (PO) course. This review examined the methods and procedures used to prevent postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD).

METHODS

A comprehensive systematic search of the literature was performed using PubMed (Medline), Embase, Web of science, and the Cochrane databases for studies published between January 1, 1990 and December 31, 2015. English language articles involving at least 100 patients undergoing PDs carried out in centers performing at least 10 PDs/y were screened for data regarding the Grade of any POPFs according to the definition of the International Study Group on Pancreatic Fistula (ISGPF) and the overall rate of PO mortality related to POPF.

RESULTS

We reviewed 7119 references through the major databases, and an additional 841 studies were identified by cross-checking the bibliographies of the full-text articles retrieved. After excluding 7379 out of 7960 studies, because they did not meet the eligibility criteria, the full texts of 581 articles were examined; 96 studies were excluded at this point, because they concerned partially or totally duplicate data that had already been reported. The remaining 485 articles were screened carefully for POPF-related mortality and POPF Grades as defined by the ISGPF. Of the 485 articles, 208 reported the POPF-related PO mortality rate and 162 the Grades (A, B, and C) of POPFs in 60,739 and 54,232 patients, respectively. The POPF-related mortality rates after pancreatojejunostomy and pancreatogastrostomy were similar but were less (0.5% vs. 1%; P = .014) when an externally draining, trans-anastomotic stent was placed intraoperatively. The incidence of the different Grades of POPF Grade was quite variable, but Grade C POPFs were associated with a PO mortality rate of 25.7% (range 0-100%).

CONCLUSIONS

The POPF-related mortality rate has remained at approximately 1% over the past 25 years. Only externally draining, trans-anastomotic stents decreased the POPF-related mortality rate. However, adequately designed venting drains were never tested in randomized controlled trials (RCTs).

The Evaluation of Internal Stent-Related Complications and Risk Factors of Stent Migration in Pancreaticoduodenectomy

The placement of an internal stent through a pancreatic anastomosis is one of the surgical techniques to reduce the incidence of pancreatic fistula. However, the fate of the internal stent after placement remains unclear. The aim of this study was to evaluate stent-related complications and risk factors of stent migration through pancreaticojejunostomy in pancreaticoduodenectomy. We retrospectively analyzed 159 patients who underwent pancreaticoduodenectomy or subtotal stomach-preserving pancreaticoduodenectomy. Stent migration and stent defecation were confirmed by computed tomography. Risk factors of delayed detachment and migration of the stent were analyzed. The median stent defecation time was 5.6 months and the stent was not expelled after 1 year in 33 patients (20.7%). Stent migration was detected in 11 patients (6.9%); the destination was always the hepatic duct. Stent-related complications were observed in 2 cases (1.3%). There were no significant risk factors of delayed detachment of the stent. Stent length ≤25 mm was the only significant predictive risk factor of stent migration into the hepatic duct in multivariate analysis. The low rate of stent-related complications and the absence of serious adverse effects observed in this study justifies that the placement of the internal stent during pancreaticoduodenectomy. Cases with delayed defecation require close and long-term follow-up, especially if a short stent was used.

Migration of Internal Pancreaticojejunostomy Stents into the Bile Ducts in Patients Undergoing Pancreatoduodenectomy

PURPOSE

To investigate the incidence, complications, and risk factors of the migration of internal pancreaticojejunostomy (PJ) stents into the bile ducts in patients undergoing pancreatoduodenectomy.

METHODS

Postoperative computed tomography (CT) and clinical data of 802 patients with CT-detectable internal PJ stents were reviewed to assess the occurrence of stent migration into the bile ducts and stent-induced complications with their clinical significance. Risk factors for stent migration and stent-induced complications were determined.

RESULTS

Stent migration into the bile ducts occurred in 135 patients (16.8 %); 40 of these (29.6 %) showed stent-induced complications including bile duct stricture, stone, and liver abscess. Clinically significant complications were identified in only eight patients. Neither the stent length nor diameter was associated with stent migration. A small stent diameter, peripheral location of the stent, absence of stent remigration from the bile ducts to the intestine, and longer stent retention time in the bile ducts were risk factors of stent-induced complications.

CONCLUSIONS

The incidence of internal PJ stent migration into the bile ducts was 16.8 %. Migrated stents frequently caused complications, although they were mostly subclinical. Stent-induced complications were associated with stent diameter and location, stent remigration to the intestine, and stent retention time in the bile ducts.

Low mortality rate in 97 consecutive pancreaticoduodenectomies: the experience of a group

CONTEXT

Pancreaticoduodenectomy is the procedure of choice for resectable cancer of the periampullary region. These tumors account for 4% of deaths from cancer, being referred to as one of the lowest survival rates at 5 years. Surgery remains a complex procedure with substantial morbidity and mortality. Despite reports of up to 30% mortality rates, in centers of excellence it have been identified as less than 5%. Recent studies show that pancreaticojejunostomy represents the "Achilles' heel" of the procedure.

OBJECTIVE

To evaluate the post-operative 30 days morbidity and mortality rates.

METHODS

Retrospective analysis of 97 consecutive resected patients between July, 2000 and December, 2012. All patients were managed by the same group, and data were obtained from specific database service. The main objective was to evaluate the 30-day mortality rate, but we also studied data of surgical specimen, need for vascular resection and postoperative complications (gastric stasis, pancreatic fistula, pneumonia and reoperation rate).

RESULTS

Thirty-day mortality rate was 2.1% (two patients). Complete resection with no microscopic residual tumor was obtained in 93.8% of patients, and in 67.3% of cases pathology did not detected metastatic nodes. Among postoperative complications were reported 6% of prolonged gastric stasis, 10.3% of pneumonia, 10.3% of pancreatic fistula and 1% of infection in the drain pathway. Two patients underwent reoperation due to bleeding and infected hematoma caused by pancreatic fistula, and another for intestinal obstruction because of adhesions at postoperative day 12.

CONCLUSIONS

The pancreaticoduodenectomy as treatment procedure for periampullary cancers has a low morbidity and mortality rate in services with experience in Hepato-Pancreato-Biliary surgery, remaining as first-line treatment in resectable patients.

Internal pancreatic stent causing irreversible dilatation of pancreatic duct

A 28-year-old woman underwent a pylorus preserving Whipple procedure for pancreatic serous cystadenoma located on the head of the pancreas. During the operation, an internal stent (7F silastic catheter, 9 cm in length) was placed within the pancreatic duct in the area of pancreaticojejunal end-to-end Dunking type anastomosis to prevent development of fistula. The stent was positioned so that one third of its length would lie into the pancreatic duct, and it was anchored to the periductal pancreatic tissue with only one rapidly absorbable chromic suture. Leakage from the anastomosis was not observed, and she was discharged without any complaint. Early postoperative abdominal CT examination revealed that the stent was retained within the normal caliber pancreatic duct (Fig. 1a). Six months after the operation, she began to complain to epigastric pain triggered by the meals. The laboratory analysis was normal, particularly liver biochemical tests and serum amylase. The internal pancreatic stent within the dilated pancreatic duct was detected by an additional CT examination (Fig. 1b). The stent was removed endoscopically at the third attempt. The pain was resolved after its removal. Control CT examination which was taken at the 18th month after removal of the stent showed dilatation of the pancreatic duct (Fig. 2a). The patient remained free of any complaint, although regressed pancreatic duct dilatation has persisted over 4 years of follow-up (Fig. 2b).

Distal migration of a transanastomotic pancreatic stent resulting in bowel perforation 19 years after pancreatoduodenectomy: report of a case

A 75-year-old woman who had undergone pancreatoduodenectomy 19 years earlier was referred to us for investigation of progressive abdominal pain without conclusive preliminary complementary tests. Computed tomography enabled us to identify that the transanastomotic pancreatic stent had migrated distally, resulting in bowel perforation. She underwent surgery and the foreign body was removed.

Whereabouts of an internal short stent placed across the pancreaticojejunostomy following pancreatoduodenectomy

BACKGROUND/PURPOSE

It is generally thought that an internal short stent placed across the pancreaticojejunostomy (PJ) following pancreatoduodenectomy (PD) usually passes spontaneously through the rectum thereafter; however, we experienced some patients who presented with pancreatitis and cholangitis owing to delayed defecation of the stent. The purpose of this study was to clarify when the stent eventually became detached from the PJ and how it passed through the body until it was finally defecated. In addition, we also investigated the factors that may prevent such detachment and defecation.

METHODS

This study retrospectively analyzed 57 patients who had had internal short stents placed across the PJ following PD. Defecation from the body, detachment from the PJ, and distal migration of the stent was confirmed by X-ray or computed tomography (CT) during the postoperative course. The cumulative rates of defecation and detachment of the stents, complications in relation to delayed defecation of the stents, and factors predictive of the delayed defecation, delayed detachment, and distal migration of the stents were analyzed.

RESULTS

Defecation of the stent was confirmed in 35 patients. The median time to defecation after PD and the cumulative defecation rate at 1 year were 454 days and 41 %, respectively. Acute pancreatitis occurred in 2 patients with the stent remaining in the pancreatic duct. One patient experienced acute cholangitis owing to migration of the stent to the bile duct. Multivariate analysis showed that ≥5 stitches in the duct-to-mucosa anastomosis, stent size of ≥5 Fr, and pancreatic fistula classified as either Grade B or C were independent predictive factors for delayed defecation of the stent. Five or more stitches in the duct-to-mucosa anastomosis was an independent predictive factor for delayed detachment of the stent. A stent size of ≥5 Fr was a risk factor for distal migration of the stent.

CONCLUSION

In more than half of the study patients, internal short stents were not defecated within 1 year. Retrieval of the stent should be considered following the migration of an internal short stent. A stent size of ≥5 Fr was an independent predictive factor for delayed defecation and distal migration of a stent. Five or more stitches in the duct-to-mucosa anastomosis was an independent predictive factor for delayed defecation and detachment of a stent.

Do transanastomotic pancreatic ductal stents after pancreatic resections improve outcomes?

OBJECTIVES

Despite strategies aimed at reducing a postoperative pancreatic fistula (POPF) after pancreatectomies, the overall incidence remains unchanged. One such procedure, until now incompletely explored, is transanastomotic pancreatic (TAP) ductal stenting.

METHODS

We conducted a systematic search using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from 1983-2008 to determine if TAP ductal stents provide any benefit and, if so, in which clinical scenarios they can be recommended.

RESULTS

Stents can be internal or external, intraoperative only, or temporary (several days). One randomized trial on internal stents across pancreaticojejunostomy (PJ) suggested a higher POPF rate in the stented group. One nonrandomized study using an internal stent for pancreaticogastrostomy (PG) revealed a 0% POPF rate. Results from studies where external stents were used across PJ/PG reported a lower incidence of POPF. No statistically significant difference was reported in a POPF incidence when internal stents were compared with externalized stents. Available data suggest improved outcomes of pancreatoenteric anastomosis when TAP ductal stent is inserted in small ducts (< or =3 mm).

CONCLUSIONS

There is insufficient evidence to support or refute improved outcomes after TAP ductal stent insertion in patients with PJ/PG with small ducts (< or =3 mm) or soft pancreata. More evidence of benefit is needed before use of external stents can be recommended.

The pancreatic stump after pancreatoduodenectomy: the "Achille's heel" revisited

Pancreatic fistula, the most dreaded complication of pancreatoduodenectomy occurs with an incidence ranging from 4-30% in literature reports; the incidence varies considerably according to the definition of fistula used. This literature review describes various methods proposed over the last decade to decrease the incidence and severity of pancreatic fistula including techniques of pancreatico-jejunal and pancreatico-gastric anastomoses, deliberate avoidance of pancreatico-enteric anastomosis, and the prophylactic role of somatostatin analogues.