External Stent Research Articles

Comparison between mini-laparoscopy, conventional laparoscopy and open approach for ureteropelvic junction obstruction treatment in children

Introduction The aim of the study was to compare 3 mm mini-laparoscopy (mini LP), standard 5 mm laparoscopy (LP) and open surgery for pediatric pyeloplasty in a single center. Methods Patients who underwent pyeloplasty from 1997 to 2017 at Hospital Sant Joan de Déu were prospectively collected. Demographic data, clinical, surgical and radiological variables were assessed. A multivariate logistic regression analysis was performed in order to identify risks for surgical complications, urinary leak and need for redo-surgery. Results 340 pyeloplasties were performed in this period: 197 open, 30 LP and 113 mini LP. Independent risk factors for surgical complications in a multivariate logistic regression model were: LP (vs mini LP, OR = 3.95; 95% CI: 1.13–13.8), higher differential renal function (each point more increases the risk 6%; 95% CI: 1–11%), older children (every year increases the risk 1.11 times; 95% CI: 1.002–1.225). Open surgery, pelvis diameter or the use of different stents were not risk factors. This model had an 80% PPV and a 92% NPV. LP (OR = 4.65; 95% CI: 1.08–19.96) and longer surgical time (OR = 1.014; 95% CI: 1.003–1.025) were independent risk factors for urinary leak. Higher pelvis diameter (OR = 0.93; 95% CI: 0.87–0.99) and the use of external stents were independent protective risk factors for urinary leak (OR = 0.09; 95% CI: 0.01–0.72). We have not found independent risk factors for redo-surgery in a multivariate logistic regression model. Conclusion mini LP can be safely and effectively used to perform pyeloplasty in pediatric patients of all ages.

External Stenting (Exostenting) to Correct Vascular Torsion and Angulation.

Organ transplantation can be associated with vascular torsions and angulations of both recipient and donor vessels. Such kinks and/or torsions of vessels can compromise the vascular integrity, obstruct inflow and/or outflow, and result in loss of the organ and/or body parts. On many occasions, mild angulations and torsions can be successfully addressed by repositioning the organ. In cases where the abnormal findings persist, maneuvers such as placing a fat pad to create a smoother curve, or even opening the peritoneum (in the case of kidney transplants) to allow for a better positioning of the organ, are associated with successful outcomes. When such torsions/angulations persist despite these approaches, further innovative tactics are required. In the current report, we propose a technique that involves longitudinally opening of a synthetic graft that is rigid enough to maintain its shape, such as a ringed polytetrafluoroethylene graft, and placing it as an external stent around the angulated/torsioned vessel. This maneuver will correct the underlying vascular compromise without having to perform any further invasive interventions, such as reimplanting the organ or resecting part of the involved vessel. Although primarily illustrated for application by describing an instance in which exostenting was applied during kidney transplantation, our approach could be applied to any vessel under many circumstances where angulations/twists are encountered. In this report, we describe the use of an external stent, also called exostenting, to correct a severe torsion/angulation of the external iliac artery in a kidney transplant recipient where all other measures were unsuccessful.

Novel external stenting for reconstruction of high flow arteriovenous fistula.

High-flow arteriovenous fistulae (HF-AVF) may lead to adverse cardiac remodeling in hemodialysis patients. We have investigated whether a novel external stent is safe and effective in reducing and stabilizing flow rates during a 1-year follow-up after HF-AVF reconstruction. All patients with HF-AVF (access flow rate ⩾ 1500 ml/min), who underwent HF-AVF reconstruction with external stenting in two centers between June 2018 and May 2020, were included in this retrospective analysis. During HF-AVF reconstruction, the dilated vein segment was resected, underwent volume reduction, and was externally stabilized using a braided cobalt-chromium external stent. AVF flow rates were assessed preoperatively, intraoperatively, and at follow up visits using duplex ultrasound. Forty-three HF-AVFs in 42 patients were reconstructed and supported with an external stent (mean age 49 years, range 20-86 years; 74% men). Fifty-one percent were forearm AVFs, 49% were upper arm. The mean preoperative flow rate was 2622 ± 893 ml/min (range: 1500-6000 ml/min) and was decreased to 710 ± 221 ml/min (range: 300-1300 ml/min) intra-operatively after HF-AVF reconstruction. At 6 and 12-months follow-up, the mean flow rates were 1132 ± 320 ml/min (range: 470-1700 ml/min) and 1453 ± 888 ml/min (range: 300-3800 ml/min), respectively. Recurrence of high flow (>1500 ml/min) occurred in 16% and 25% of the patients at 6 and 12 months and primary patency rates were 86% and 70%, respectively. This early experience with novel external stenting for HF-AVF reconstruction demonstrates that it is a safe and effective method for reducing and stabilizing flow rates up to 1-year post procedure. Additional studies are required to evaluate the durability of this procedure over the longer term and assess its effect on cardiac remodeling.

External stenting and disease progression in saphenous vein grafts two years after coronary artery bypass grafting: A multicenter randomized trial

ObjectivesLittle data exist regarding the potential of external stents to mitigate long-term disease progression in saphenous vein grafts. We investigated the effect of external stents on the progression of saphenous vein graft disease. MethodsA total of 184 patients undergoing isolated coronary artery bypass grafting, using an internal thoracic artery graft and at least 2 additional saphenous vein grafts, were enrolled in 14 European centers. One saphenous vein graft was randomized to an external stent, and 1 nonstented saphenous vein graft served as the control. The primary end point was the saphenous vein graft Fitzgibbon patency scale assessed by angiography, and the secondary end point was saphenous vein graft intimal hyperplasia assessed by intravascular ultrasound in a prespecified subgroup at 2 years. ResultsAngiography was completed in 128 patients and intravascular ultrasound in the entire prespecified cohort (n = 51) at 2 years. Overall patency rates were similar between stented and nonstented saphenous vein grafts (78.3% vs 82.2%, P = .43). However, the Fitzgibbon patency scale was significantly improved in stented versus nonstented saphenous vein grafts, with Fitzgibbon patency scale I, II, and III rates of 66.7% versus 54.9%, 27.8% versus 34.3%, and 5.5% versus 10.8%, respectively (odds ratio, 2.02; P = .03). Fitzgibbon patency scale was inversely related to saphenous vein graft minimal lumen diameter, with Fitzgibbon patency scale I, II, and III saphenous vein grafts having an average minimal lumen diameter of 2.62 mm, 1.98 mm, and 1.32 mm, respectively (P < .05). Externally stented saphenous vein grafts also showed significant reductions in mean intimal hyperplasia area (22.5%; P < .001) and thickness (23.5%; P < .001). ConclusionsTwo years after coronary artery bypass grafting, external stenting improves Fitzgibbon patency scales of saphenous vein grafts and significantly reduces intimal hyperplasia area and thickness. Whether this will eventually lead to improved long-term patency is still unknown.

External stenting of vein grafts in coronary artery bypass grafting: interim results from a two centers prospective study

Backgroundprevious studies evaluating external stents for saphenous vein grafts (SVG) in CABG were limited to on-pump isolated CABG and single grafting technique with one external stent per patient. The objective of this prospective study was to evaluate the safety and the short-term performance of external stents in a heterogeneous group of patients who underwent on- and off-pump CABG, single and sequential grafting.Methods102 patients undergoing CABG were enrolled in two centers. All patients received internal mammary artery to the left anterior descending artery and additional arterial and/or venous grafts. In each patient, at least one SVG was supported with an external stent. Grafts’ patency and SVG lumen uniformity were assessed using CT angiography at a pre-defined time window of 6–12 months post procedure. All patients were prospectively followed-up via phone call and/or visit every 6 months for Major Adverse Cardiac and Cerebrovascular Events.Results51 patients (50%) underwent off-pump CABG and 23 patients (23%) were grafted with bilateral internal mammary arteries. Each patient received one or more SVG grafted in a sequential technique (44%) or as a single graft (56%). All SVG were externally stented in 84% of patients and in 16% (n = 16) one SVG was stented and one remained unsupported. At 6–12 months, patency rates of LIMA, RIMA, externally stented SVG and none-stented SVG were 100, 100, 98 and 87.5% respectively. 90% of the externally stented SVG had uniform lumen compared to 37% of the non-stented SVG. Clinical follow-up was completed for all patients with a mean duration of 20 months (range 6–54 months). During follow up period, one patient experienced myocardial infarction due to occlusion of the LIMA-LAD graft and one patient experienced a transient ischemic attack.ConclusionsExternal stenting of SVG is feasible and safe in CABG setting which includes off pump CABG and sequential SVG grafting and associated with acceptable early patency rates.Trial registrationStudy was registered at ClinicalTrials.gov. NCT01860274 (initial release 20.05.2013).

External stenting and disease progression in vein grafts 1 year after open surgical repair of popliteal artery aneurysm

ObjectiveOpen surgical repair remains the gold standard treatment for popliteal artery aneurysms (PAA). The objective of this study was to evaluate the safety of external stenting and its medium-term effect on vein graft disease after open PAA repair. MethodsBetween December 2017 and September 2019, 12 consecutive patients with PAA underwent open surgical repair with externally stented saphenous vein grafts. Duplex ultrasound scanning of the grafts was performed at discharge and at 3, 6, and 12 months after the procedure to evaluate graft patency, average lumen diameter and lumen uniformity. ResultsEleven patients underwent aneurysm ligation and bypass grafting and one patient was treated with aneurysm exclusion and interposition of a venous segment. External stenting of the vein graft was successful in all patients. The mean follow-up time was 12 months (range, 7-17 months), with a primary patency rate of 100% and no graft revisions or reinterventions. The mean lumen diameters at 3, 6, and 12 months were 5.9 ± 1.2 mm, 5.7 ± 0.8 mm, and 5.7 ± 0.7 mm, respectively, with no significant changes between 3 and 6 (P = .34) and between 6 and 12 months (P = .34). The coefficient of variance at 3, 6, and 12 months was 8.2 ± 9.3, 9.4 ± 7.2, and 10.4 ± 8.9, respectively, with no significant change between 3 and 6 months (P = .78) or 6 and 12 months (P = .98). No mortality or amputations were recorded throughout the follow-up period. ConclusionsExternal stenting of vein grafts in open surgical repair of PAA is feasible and safe. This technique may potentially improve the outcomes of surgical repair in patients with PAA.

The prognostic value of external vs internal pancreatic duct stents after pancreaticoduodenectomy in patients with FRS\u2009\u2265\u20094: a retrospective cohort study

BackgroundThe prognostic value of external vs internal pancreatic duct stents after pancreaticoduodenectomy remains controversial. This study aimed to evaluate the benefits of external and internal stents using the Fistula Risk Score system with regard to the incidence of clinically relevant postoperative pancreatic fistula.MethodsA total of 382 patients who underwent pancreaticoduodenectomy with duct to mucosa pancreaticojejunostomy were retrospectively enrolled from January 2015 to October 2019. The receiver operating characteristic curve was performed for subgroup analysis of the patients at different levels of risk for pancreatic fistula.ResultsThere were no significant differences in terms of pancreatic fistula or other postoperative complications. According to the receiver operating characteristic curve threshold of 3.5, 172 patients with a Fistula Risk Score ≥ 4 and 210 patients with a Fistula Risk Score < 4 were divided into separate groups. The number of valid cases was insufficient to support the subsequent research in patients with a Fistula Risk Score < 4. In patients with a Fistula Risk Score ≥ 4, the use of an external pancreatic duct stent was significantly more effective than the use of an internal stent, especially with regard to the risk for pancreatic fistula (Grade C) (P = 0.039), at ameliorating the incidence of clinically relevant postoperative pancreatic fistula (P = 0.019). Additionally, the incidence of lymphatic leakage was significantly higher in the external stent group compared with the internal stent group (P = 0.040).ConclusionsCompared with internal stents, the use of an external stent could reduce the incidence of clinically relevant postoperative pancreatic fistula in patients with a Fistula Risk Score ≥ 4. More large-scale prospective clinical trials are warranted to further clarify our results.

Identification of High-risk Patients of Clinically Relevant Postoperative Pancreatic Fistula

Background: Pancreatic fistula (POPF) remains a significant concern after pancreaticoduodenectomy (PD). Recently, there have been the development of risk-stratification and increasing needs in the management base on such risk-model. The purpose of this study was to examine the identification of risk factor and the invention of risk-model using these risk factors. Methods: Patient characteristics, preoperative laboratory, and radiographic findings and their association with postoperative pancreatic fistula after pancreaticoduodenectomy were analyzed for 158 patients who underwent resection between 2011 and 2017. CR-POPF was defined as Grade B or C pancreatic fistula based on the International Study Group of Pancreatic Surgery (ISGPS) 2016 consensus. Results: CR-POPF developed in 38 patients (24.2%). On multivariate logistic analysis, abdominal fat area (ORs=1.006; P=0.05), main pancreatic duct diameter (ORs=0.72; P=0.0008), diabetes mellitus (ORs=4.8; P=0.0038) and the pathology of non-pancreatic cancer (ORs=6.3; P=0.0002). The risk-model based on these factors classified the high risk group, whose discriminant score was above 0.70. To prevent the development and deterioration of POPF, modified Blumgart method, external stenting of bile and pancreatic secretion and continuous irrigation after POPF were instituted. After 2018, 5 patients out of 60 patients in total was the high-risk group. Among them, 1 patient underwent CR-POPF. No patients experienced Grade C POPF. Conclusions: The risk assessment based on preoperative factors for the prediction of POPF after PD was considered as effective in view of the identification of high risk patients and intervention to them. However, the rate of POPF remains high despite several improvement of perioperative management.

Short internal pancreatic stent reduces pancreatic fistula in pancreatoduodenectomy.

Clinically relevant postoperative pancreatic fistula (CR-POPF) is a major complication of pancreatoduodenectomy (PD). A pancreatic stent is usually used for drainage of the pancreatic duct, but the best type of the stent remains unclear. The aim of this study was to investigate perioperative factors and their influence on the risk of CR-POPF following PD. From 2006 to 2019, the records of 246 patients who underwent PD were retrospectively reviewed, and the relationship between perioperative factors including type of pancreatic stent and CR-POPF was investigated. External or internal pancreatic stents were used for drainage of the pancreatic duct, and the internal stent was inserted 1 cm into the jejunum to decrease stent obstruction. External and internal pancreatic stents were used in 137 and 109 patients, respectively. Multivariate analysis revealed that the diameter of the main pancreatic duct (odds ratio = 0.292, 95% confidence interval = 0.140-0.605, P = 0.001), diagnosis (odds ratio = 3.359, 95% confidence interval = 1.498-7.693, P = 0.003), and type of pancreatic stent (odds ratio = 0.435, 95% confidence interval = 0.203-0.934, P = 0.033) were independent factors related to CR-POPF after PD. Internal stent was associated with a low rate of CR-POPF (P < 0.001) and short postoperative hospital stay (P < 0.001) compared to external stent. A short pancreatic internal stent could decrease the incidence of CR-POPF.

Trans-uretero-cystic external urethral stent for urinary diversion in pediatric laparoscopic pyeloplasty: A novel approach.

Purpose:We present a new approach for urine drainage in pediatric patients following laparoscopic pyeloplasty, the trans-uretero-cystic external urethral stent (TEUS).Methods:We retrospectively identified 85 children who underwent laparoscopic pyeloplasty from July 2015 to June 2017. The included children were assigned to group A (double-J stent) or group B (TEUS). In group A, the double-J stent was removed by a cystoscopy under anesthesia after 1 month, while in group B, the external stent was removed after 5 to 7 days. We examined the durations of operation, hospital stay and the frequency of stent-related complications including urinary leakage, stent dislocation, stent occlusion, and urinary tract infection.Results:The operation time was significantly longer for patients in group B than for those in group A. No significant difference was observed between the groups regarding stent-related complications. In group A, 4 patients need auxiliary stent re-insertion for the management of complications, 2 developed urinary tract infection, and 2 had stent occlusion. In group B, none needed auxiliary stent re-insertion for complications and avoided re-operation.Conclusions:In children, the outcome of external stent implantation was similar to that using double-J stent, and the use of the former approach may be beneficial for younger children.

Impact of referral pattern and timing of repair on surgical outcome after reconstruction of post-cholecystectomy bile duct injury: A multicenter study

BackgroundBile duct injury (BDI) after cholecystectomy remains a significant surgical challenge. No guideline exists to guide the timing of repair, while few studies compare early versus late repair BDI. This study aimed to analyze the outcomes in patients undergoing immediate, intermediate, and delayed repair of BDI. MethodsWe retrospectively analyzed 412 patients with BDI from March 2015 to January 2020. The patients were divided into three groups based on the time of BDI reconstruction. Group 1 underwent an immediate reconstruction (within the first 72 hours post-cholecystectomy, n = 156); group 2 underwent an intermediate reconstruction (from 4 days to 6 weeks post-cholecystectomy, n = 75), and group 3 underwent delayed reconstruction (after 6 weeks post-cholecystectomy, n = 181). ResultsPatients in group 2 had significantly more early complications including anastomotic leakage and intra-abdominal collection and late complications including anastomotic stricture and secondary liver cirrhosis compared with groups 1 and 3. Favorable outcome was observed in 111 (71.2%) patients in group 1, 31 (41.3%) patients in group 2, and 157 (86.7%) patients in group 3 (P = 0.0001). Multivariate analysis identified that complete ligation of the bile duct, level E1 BDI and the use of external stent were independent factors of favorable outcome in group 1, the use of external stent was an independent factor of favorable outcome in group 2, and level E4 BDI was an independent factor of unfavorable outcome in group 3. Transected BDI and level E4 BDI were independent factors of unfavorable outcome. ConclusionsFavorable outcomes were more frequently observed in the immediate and delayed reconstruction of post-cholecystectomy BDI. Complete ligation of the bile duct, level E1 BDI and the use of external stent were independent factors of a favorable outcome.

Effect of continuous antibiotic prophylaxis in children with postoperative JJ stents: A prospective randomized study

We aimed to investigate the effectiveness of continuous antibiotic prophylaxis (CAP) in patients with JJ stent and tried to identify the group that could specifically benefit from CAP by a prospective randomized study. A prospective, randomized, controlled, non-blind, non-placebo study was performed in a single center.A total of 105 patients who underwent surgery with JJ stent (PNL, URS, pyeloplasty, UNC) were randomized into two groups. 53 patients in Group A received CAP and 52 patients in Group B were controlled without CAP, during the presence of a JJ stent. Patients with external stents, nephrostomy tubes, indwelling long-term urethral catheters were excluded. History of preoperative use of CAP and lower urinary tract symptoms were noted. Trimethoprim/sulfamethoxazole (TMP/SMX) was used as the initial choice of antibiotic however if there was a history of antibiotic resistance in previous urinary cultures, Nitrofurantoin was administrated. Urinary cultures were obtained before surgery and before stent extraction. JJ stents were sent to culture. Symptomatic febrile urinary tract infections with positive urine cultures (105 CFU on a clean catch or 103with urethral catheterization) were compared between groups. Our study has some limitations; the study is the single-center, we did not follow-up of patients in terms of scar, there were low number of uncircumcised patients, multiple types of surgical procedures were performed. JJ stent is a frequently used instrument in children. Unfortunately, any randomized prospective on antibiotics administration while using a JJ stent is not available in the current literature. We hope our research will contribute to the existing literature and cause a significant change in clinical practice. The mean age among all patients was 4.8±3.9 years. The mean length of time jj stents stayed inside was 16.34±6.45 days in group A and 15.29±7.71 days in group B. The incidence of febrile urinary tract infections with CAP was significantly reduced (3.8% vs. 19% (p 0.015)). Multivariate regression analysis revealed that a positive history for preop febrile urinary tract infections and/or LUTS has a significantly higher association with the incidence of febrile urinary tract infecitons. CAP in the presence of JJ stents reduced the incidence of febrile urinary tract infections in a short period, especially in children with the previous history of febrile urinary tract infections and lower urinary tract symptoms.

A Soft, Conductive External Stent Inhibits Intimal Hyperplasia in Vein Grafts by Electroporation and Mechanical Restriction.

Intimal hyperplasia (IH) in vein grafts (VGs) is a major issue in coronary artery bypass grafting (CABG) surgery. Although external stents can attenuate IH of VGs to some extent, none of the existing external stents have shown satisfactory clinical outcomes. Here we develop a flexible, biodegradable, and conductive external metal-polymer conductor stent (MPCS) that can electroporate the vessel wall and produce a protein that prevents IH. We designed the plasmid DNA encoding the tissue inhibitor of metalloproteinases-3 (TIMP-3) and lyophilized it on the inner surface of the MPCS to deliver into the adventitia and the middle layer of VGs for gene therapy. Coupled with its continuous mechanical support to prevent dilation after implanting, the MPCS can inhibit the IH of VGs significantly in the rabbit model. This proof-of-concept demonstration may aid the development of other implantable bioelectronics for electroporation gene therapy.

Effects of planar and nonplanar curved flow paths on the hemodynamics of helical conduits for coronary artery bypass grafting: A numerical study

Helical geometries to induce swirling and spiral flow in prosthetic grafts have been hypothesized as a possible way to improve the clinical outcomes in patients undergoing coronary artery bypass grafting. In this paper, the transient flow behavior in helical bypass conduits with two different curved flow paths (planar and nonplanar) was investigated. Numerical methods were used to examine the flow physics downstream of four idealized bypass conduits attached to an aorta. The flow field in the bypass conduits was examined based on a non-Newtonian blood-analog fluid with relevant physiological waveforms characterized by a Womersley number α of 2.13 and a mean Reynolds number Remean of 107. The effects of nonplanar curvature and helicity were studied independently based on four idealized grafts. For all models, the axial flow downstream of the grafts resembles the oscillatory flow in straight tubes with a low α. The local secondary flow structures correspond closely to the strength of the swirling flow induced by the helical geometry. The helical conduit with a planar curved flow path in general consists of a pair of asymmetric vortices downstream. The introduction of a nonplanar curved flow path significantly increases the degree of asymmetry and leads to the transition from a double-vortex structure to a single swirling vortex flow. It is demonstrated that the swirling flow induced by the planar curvature promotes greater in-plane mixing downstream of the graft than the nonplanar curvature. However, the analysis of hemodynamic parameters reveals the effectiveness of a nonplanar curved flow path in the helical conduit in significantly elevating the overall mean wall shear stress. These findings demonstrate the possibility of using helical geometries and nonplanar curved flow paths in the design of external stents to independently control the mixing behavior and hemodynamic environment in coronary bypass conduits.

Application of an extracorporeal prefenestrated stent graft in endovascular repair of ascending aorta and aortic arch lesions

Aortic dissection involving the ascending aorta and aortic arch is a serious condition. Treatment using traditional surgical methods has certain disadvantages. This study investigated the effectiveness of thoracic endovascular repair of aortic dissection using an external prefenestrated stent. We present a series of aortic dissection cases involving the ascending aorta and aortic arch treated with an external prefenestrated stent. Postoperative follow-up of the patients showed that all stents were released at the proper position and that branch vessels were not occluded, and there were no instances of type I endoleak. One patient died suddenly one week after surgery; another experienced retrograde type A aortic dissection in the second week; and type I endoleak occurred in one patient in the first week, although this resolved within six months. No serious complications such as cerebrovascular events, acute spinal cord ischemia, and paraplegia occurred during the perioperative period. All patients had false lumen thrombosis in the ascending aorta and aortic arch. Prefenestrated stent grafting is a feasible treatment option for repairing an entry tear in the ascending aorta.

A novel biodegradable external stent regulates vein graft remodeling via the Hippo-YAP and mTOR signaling pathways

Coronary artery bypass graft (CABG) has been confirmed to effectively improve the prognosis of coronary artery disease, which is a major public health concern worldwide. As the most frequently used conduits in CABG, saphenous vein grafts have the disadvantage of being susceptible to restenosis due to intimal hyperplasia. To meet the urgent clinical demand, adopting external stents (eStents) and illuminating the potential mechanisms underlying their function are important for preventing vein graft failure. Here, using 4-axis printing technology, we fabricated a novel biodegradable and flexible braided eStent, which exerts excellent inhibitory effect on intimal hyperplasia. The stented grafts downregulate Yes-associated protein (YAP), indicating that the eStent regulates vein graft remodeling via the Hippo-YAP signaling pathway. Further, as a drug-delivery vehicle, a rapamycin (RM)-coated eStent was designed to amplify the inhibitory effect of eStent on intimal hyperplasia through the synergistic effects of the Hippo and mammalian target of rapamycin (mTOR) signaling pathways. Overall, this study uncovers the underlying mechanisms of eStent function and identifies a new therapeutic target for the prevention of vein graft restenosis.

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

BackgroundSeveral 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). MethodsWe 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). ResultsAfter 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). ConclusionPropensity score matched analysis showed that, regarding clinically relevant pancreatic fistula after PD, internal stents are safer than external stents for pancreaticojejunostomy.

Redefining the Role of Drain Amylase Value for a Risk-Based Drain Management after Pancreaticoduodenectomy: Early Drain Removal Still Is Beneficial

BackgroundThe application of postoperative pancreatic fistula (POPF) risk stratification and mitigation strategies requires an update of the protocol for an early drain removal after pancreaticoduodenectomy (PD). The aim of the study is to highlight the unreliability of a single drain fluid amylase (DFA) cutoff-based protocol in the setting of a risk-based drain management. MethodsThe role of postoperative day one (POD1) DFA in predicting POPF was explored in the setting of both selective drain placement and early drain removal protocols. Receiver operating characteristics (ROC) curves were used to assess the POPF diagnostic performance in terms of negative predictive value (NPV) of several POD1 DFA cutoffs in different clinical scenarios according to POPF risk and mitigation strategies. ResultsThe areas under the curve (AUCs) for POD1-DFA were 0.815 for intermediate risk and pancreaticojejunostomy (PJ) (best cutoff 1000 IU/L, NPV 92.9%), 0.712 for intermediate risk and PJ with external stent (best cutoff 1000 IU/L, NPV 88.8%), and 0.574 for high risk and external stent (best cutoff 250 IU/L, NPV 93.7%). Independent predictors of POPF were body mass index, pancreatic texture, and early drain removal, whereas POD1 DFA was not. ConclusionIn the era of risk stratification and mitigation strategies, selective early drain removal still is associated with a reduced rate of POPF. However, a single protocol based on POD1-DFA is not suitable for all clinical scenarios after PD.

Bioabsorbable Microplates as an External Stent for Suprastomal Collapse: A Retrospective Review.

To assess the long-term decannulation outcomes of bioresorbable microplates as an external stent for pediatric tracheostomy patients with suprastomal collapse. Retrospective cohort study. Hospital records of all patients who underwent a bioresorbable microplate for suprastomal collapse from 2016 to 2019 were reviewed at a single institution. The primary outcome measure was tracheostomy decannulation. A total of nine patients underwent placement of bioabsorbable microplates to treat suprastomal collapse. After initial tracheostomy, four patients received a laryngotracheal reconstruction prior to their external stent placement, and one patient received a mandibular distraction. The average age at the time of external stent placement was 32 (±21) months, excluding one patient who received a stent at the age of 29 years. Eight patients (88.9%) were successfully decannulated following the procedure. Decannulated patients were followed for an average of 21 (±12.5) months postoperatively, and all these patients have remained decannulated since their initial procedure. This is a total of 173 months (14.4 years) of observation postprocedure in which these patients have remained decannulated. One patient experienced postoperative crepitus requiring washout but still maintained decannulation. Bioabsorbable microplates have a reasonable chance of long-term successful decannulation when an appropriate patient is selected. Decannulation is maintained beyond the 6-month time frame in which the 85:15 poly(L-lactide-co-glycolide) polymer that comprises the external stent takes to bioabsorb. This procedure should be considered for the often difficult problem of pediatric tracheostomy with isolated suprastomal collapse. 4 Laryngoscope, 131:E631-E634, 2021.

Choice of urine derivation method after radical cystectomy in the high anesthesiological risk group

Background. Radical cystectomy is the standard treatment for muscle-invasive bladder cancer. Muscle invasion can occur in 48 % of patients. Epidemiologically, the peak incidence of bladder cancer is observed in men at the seventh decade of life. At the time of diagnosis, many of these patients have serious comorbidity. The trauma of radical cystectomy in combination with comorbidity creates an insurmountable barrier to radical treatment in a large part of patients. Refusal to use intestinal segments for urine diversion dramatically reduces the invasiveness of the intervention. However, the implementation of bilateral ureterocutaneostomy is associated with a greater frequency of pyelonephritis due to the use of external stents and scarring of the ureterocutaneostomy. A transureteroureterostomy with a unilateral ureterocutaneostomy can be a definite alternative.Objective: to evaluate the effectiveness of cross ureteroureterostomy for urine derivation after radical cystectomy in patients with muscle-invasive bladder cancer and a high risk of perioperative complications.Materials and methods. The article analyzes 28 cystectomies for muscle-invasive bladder cancer in patients with severe concomitant pathology who underwent transureteroureterostomy with unilateral ureterocutaneostomy for urine derivation. Results. It was shown that this intervention does not have high morbidity, does not increase the incidence of early postoperative complications, and relieves patients from bilateral urostoma. Among late complications, inflammatory ones predominate due to obstruction of the external stent. The authors highlight the tactics and technical aspects of managing such patients with obstructive pyelonephritis and the experience of drainage-free management.Conclusion. Transureteroureterostomy with unilateral ureterocutaneostomy after cystectomy for muscle-invasive bladder cancer can be considered as the operation of choice in patients with a burdened comorbidity.