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Displacement of pancreatic stent — Clinical Guidelines

Overview

Displacement of pancreatic stents, particularly lumen-apposing metal stents (LAMS) used in the endoscopic management of pancreatic fluid collections (PFCs), is a significant complication that can compromise therapeutic outcomes. This condition primarily affects patients with necrotizing pancreatitis who require endoscopic drainage to manage PFCs effectively. The displacement of these stents can lead to recurrent fluid collections, infection, and the need for additional interventions, impacting patient recovery and hospital stay. Understanding and managing stent displacement is crucial for optimizing clinical outcomes in day-to-day practice 1.

Pathophysiology

The pathophysiology of pancreatic stent displacement often stems from the complex nature of necrotizing pancreatitis, where extensive necrosis and irregular cavity walls contribute to stent dislodgement. LAMS, while advantageous for their large diameter and reduced risk of perforation, are more prone to displacement due to their rigid structure compared to flexible plastic stents. The sealing of the cavity over time can also exert forces that dislodge the stent, especially if not exchanged promptly for plastic stents to prevent disconnected pancreatic duct syndrome (DPDS). Additionally, technical challenges during stent placement, such as improper positioning or inadequate fixation, can predispose to displacement 1.

Epidemiology

The incidence of pancreatic stent displacement is not extensively detailed in the provided sources, but it is recognized as a notable complication in patients undergoing endoscopic interventions for PFCs. These patients typically include adults with severe acute pancreatitis leading to necrosis and subsequent PFC formation. Geographic and demographic variations are not specifically highlighted, but high-volume centers treating a larger number of severe cases may observe higher incidences. Trends suggest an increasing use of LAMS, potentially correlating with a rise in displacement events due to their unique challenges 1.

Clinical Presentation

Clinical presentation of displaced pancreatic stents often includes recurrent symptoms indicative of PFC accumulation, such as abdominal pain, fever, and signs of infection like leukocytosis. Imaging studies, particularly contrast-enhanced CT scans or endoscopic ultrasound (EUS), are crucial for identifying displaced stents and assessing the nature of fluid collections. Red-flag features include rapid clinical deterioration, persistent fever unresponsive to antibiotics, and imaging evidence of fluid accumulation around the displaced stent site 1.

Diagnosis

Diagnosis of displaced pancreatic stents involves a combination of clinical assessment and imaging modalities:

Clinical Evaluation: Recurrent symptoms post-stent placement, particularly those suggestive of fluid collection recurrence.

Imaging Studies:

- Contrast-Enhanced CT Scan: Identifies fluid collections and displaced stent location. - Endoscopic Ultrasound (EUS): Provides detailed visualization of the stent position and surrounding structures.

Endoscopic Re-evaluation: Direct visualization during endoscopy to confirm stent displacement.

Differential Diagnosis:

- Persistent Necrosis: Differentiates based on imaging showing ongoing necrosis rather than fluid collection. - Infection: Elevated inflammatory markers and imaging findings consistent with abscess formation. - Stent Occlusion: Contrast studies may show obstruction rather than displacement 1 7.

Management

Initial Management

Clinical Monitoring: Close observation for signs of complications such as infection or worsening symptoms.

Imaging Follow-Up: Regular CT scans or EUS to assess fluid collections and stent position.

Interventional Steps

Endoscopic Retrieval or Replacement:

- Endoscopic Retrieval: Attempt to reposition or retrieve the displaced stent endoscopically. - Exchange for Plastic Stents: If retrieval is not feasible, exchange LAMS for plastic stents to maintain drainage and prevent DPDS.

Additional Drainage:

- Percutaneous Catheter Drainage: If endoscopic management fails, consider percutaneous drainage to manage fluid collections. - Repeat Endoscopic Necrosectomy: In cases of significant necrosis, surgical or endoscopic necrosectomy may be required.

Refractory Cases

Surgical Intervention: Referral to surgical management if endoscopic and percutaneous approaches fail, including potential resection or bypass procedures.

Antibiotic Therapy: Initiate broad-spectrum antibiotics if signs of infection are present, adjusting based on culture and sensitivity results.

Contraindications:

Severe coagulopathy or bleeding disorders precluding endoscopic procedures.

Uncontrolled sepsis requiring immediate surgical intervention 1 7.

Complications

Acute Complications

Infection: Risk of abscess formation around displaced stents.

Recurrent Fluid Collections: Fluid accumulation leading to clinical deterioration.

Peritonitis: Rare but severe complication if leakage occurs.

Long-Term Complications

Chronic Pancreatitis: Prolonged inflammation and scarring.

Stent-Related Granulomas: Formation of granulomas around the stent material.

Recurrent PFC: Persistent fluid collections necessitating repeated interventions 1.

Management Triggers

Persistent Fever and Leukocytosis: Indicative of infection requiring prompt antibiotic therapy and imaging.

Symptomatic Fluid Accumulation: Requires immediate reassessment and intervention to prevent complications.

Clinical Deterioration: Early referral to surgical or interventional radiology teams 1.

Prognosis & Follow-Up

The prognosis for patients with displaced pancreatic stents varies based on the rapidity and effectiveness of intervention. Prompt management can lead to favorable outcomes with resolution of fluid collections and stabilization of symptoms. Prognostic indicators include:

Timeliness of Intervention: Early retrieval or replacement of stents improves outcomes.

Absence of Infection: Patients without signs of infection generally have better prognoses.

Size and Location of PFC: Smaller, more accessible collections are easier to manage.

Recommended Follow-Up:

Imaging: Repeat CT scans or EUS at 2-4 weeks post-intervention to ensure resolution of fluid collections.

Clinical Assessment: Regular follow-up visits to monitor symptom resolution and detect early signs of recurrence or complications.

Endoscopic Reassessment: Periodic endoscopic evaluations to ensure proper stent function or absence of retained stents 1.

Special Populations

Pediatrics

Limited data exist on the use of LAMS in pediatric patients, but similar principles apply with a focus on minimizing complications through careful stent selection and monitoring.

Elderly Patients

Elderly patients may have increased comorbidities affecting tolerance to interventions; careful risk stratification and multidisciplinary management are essential.

Comorbidities

Patients with significant comorbidities such as coagulopathies or severe cardiovascular disease require tailored approaches, possibly involving more conservative management initially 1.

Key Recommendations

Prompt Endoscopic Re-evaluation: Regularly reassess patients with displaced stents via endoscopy to ensure proper drainage and prevent complications (Evidence: Strong 1).

Exchange LAMS for Plastic Stents: Exchange lumen-apposing metal stents for plastic stents within 4 weeks to minimize recurrence of PFCs and risk of disconnected pancreatic duct syndrome (Evidence: Moderate 1 7).

Imaging Surveillance: Utilize contrast-enhanced CT scans or EUS for regular imaging follow-up to monitor fluid collections and stent position (Evidence: Moderate 1).

Early Antibiotic Therapy: Initiate broad-spectrum antibiotics promptly in cases of suspected infection to prevent sepsis (Evidence: Moderate 1).

Surgical Consultation for Refractory Cases: Refer patients with persistent symptoms or complications to surgical intervention if endoscopic and percutaneous methods fail (Evidence: Expert opinion 1).

Monitor for Recurrent Symptoms: Closely monitor patients for signs of recurrent fluid collections or clinical deterioration post-intervention (Evidence: Moderate 1).

Timely Exchange or Retrieval: Prioritize timely endoscopic retrieval or replacement of displaced stents to prevent complications (Evidence: Strong 1).

Consider Percutaneous Drainage: Employ percutaneous catheter drainage as an adjunct if endoscopic management is unsuccessful (Evidence: Moderate 1).

Multidisciplinary Approach: Involve gastroenterology, interventional radiology, and surgery in managing complex cases (Evidence: Expert opinion 1).

Patient Education: Educate patients on recognizing signs of complications and the importance of follow-up appointments (Evidence: Expert opinion 1).

References

1 Bang JY, Wilcox CM, Arnoletti JP, Peter S, Christein J, Navaneethan U et al.. Validation of the Orlando Protocol for endoscopic management of pancreatic fluid collections in the era of lumen-apposing metal stents. Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society 2022. link 2 Wensheg L, Shunrong J, Wenyan X, Yihua S, Mengqi L, Zheng L et al.. Completely 3-dimensional laparoscopic pancreaticoduodenectomy with modified Blumgart pancreaticojejunostomy: an analysis of 100 consecutive cases. Langenbeck's archives of surgery 2023. link 3 Hwang JS, Seo DW, So H, Ko SW, Joo HD, Oh D et al.. Clinical utility of directional eFLOW compared with contrast-enhanced harmonic endoscopic ultrasound for assessing the vascularity of pancreatic and peripancreatic masses. Pancreatology : official journal of the International Association of Pancreatology (IAP) ... [et al.] 2022. link 4 Yoshida M, Naitoh I, Hayashi K, Hori Y, Natsume M, Kato A et al.. Various innovative roles for 3-Fr microcatheters in pancreaticobiliary endoscopy. Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society 2022. link 5 Mahmoud T, Wong Kee Song LM, Stavropoulos SN, Alansari TH, Ramberan H, Fukami N et al.. Initial multicenter experience using a novel endoscopic tack and suture system for challenging GI defect closure and stent fixation (with video). Gastrointestinal endoscopy 2022. link 6 Kuwatani M, Kawakubo K, Sakamoto N. Possible reasons for the regrettable results of patency of an inside stent in endoscopic transpapillary biliary stenting. Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society 2022. link 7 Shinn B, Boortalary T, Raijman I, Nieto J, Khara HS, Kumar SV et al.. Maximizing success in single-session EUS-directed transgastric ERCP: a retrospective cohort study to identify predictive factors of stent migration. Gastrointestinal endoscopy 2021. link 8 Klompmaker S, de Rooij T, Koerkamp BG, Shankar AH, Siebert U, Besselink MG et al.. International Validation of Reduced Major Morbidity After Minimally Invasive Distal Pancreatectomy Compared With Open Pancreatectomy. Annals of surgery 2021. link 9 Aoki T, Koizumi T, Mansour DA, Fujimori A, Kusano T, Matsuda K et al.. Virtual reality with three-dimensional image guidance of individual patients' vessel anatomy in laparoscopic distal pancreatectomy. Langenbeck's archives of surgery 2020. link 10 Fung A, Kelly P, Tait G, Greig PD, McGilvray ID. Creating an animation-enhanced video library of hepato-pancreato-biliary and transplantation surgical procedures. Journal of visual communication in medicine 2016. link 11 Kawahara R, Akasu G, Ishikawa H, Yasunaga M, Kinoshita H. A questionnaire on the educational system for pancreatoduodenectomy performed in 1,134 patients in 71 institutions as members of the Japanese Society of Pancreatic Surgery. Journal of hepato-biliary-pancreatic sciences 2013. link 12 Soh YF, Kow AW, Wong KY, Wang B, Chan CY, Liau KH et al.. Perioperative outcomes of laparoscopic and open distal pancreatectomy: our institution's 5-year experience. Asian journal of surgery 2012. link 13 Mueglitz J, Kunad G, Dautzenberg P, Neisius B, Trapp R. Kinematic problems of manipulators for minimal invasive surgery. Endoscopic surgery and allied technologies 1993. link 14 Drastik J, Skàla I, Pirk F. Overfilling of a pancreatic segment in endoscopic retrograde pancreaticography. Endoscopy 1978. link

Displacement of pancreatic stent