Endoscopic vacuum therapy for gastrointestinal transmural defects: a literature review
Article information
Abstract
Endoscopic vacuum therapy (EVT) has emerged as a transformative approach for managing gastrointestinal (GI) transmural defects, offering a less invasive and more promising alternative to surgery. Initially developed to address anastomotic leaks after rectal surgery, the application of EVT has expanded to include other locations within the GI tract. This review investigated the principles, indications, procedures, outcomes, challenges, and future perspectives of EVT for the management of GI transmural defects. In conclusion, EVT has demonstrated favorable outcomes in GI defect closure, with reduced complications, shortened hospital stay, and decreased morbidity rates as compared with conventional treatments. Although EVT faces challenges in some specific anatomical locations and in managing severe complications such as major bleeding, ongoing advancements in technology and standardization efforts offer promise for broader indications and better outcomes. Future perspectives include exploring novel EVT devices, refining patient selection criteria and pre-emptive applications, and standardizing procedural protocols.
INTRODUCTION
Gastrointestinal (GI) transmural defects encompass a spectrum of conditions, including perforations, leakages, or fistulas within the GI tract.1 These may arise iatrogenically as a result of various therapeutic procedures, including post-operative complications and diagnostic or interventional endoscopy, or spontaneously due to factors such as ulcers or tumors.
Management of GI transmural defects depends on the severity of complications and the patient’s overall condition.1,2 Small perforations, leakages, and fistulas without signs of sepsis often warrant conservative management. However, larger defects (>3 cm) or those complicated by sepsis require prompt endoscopic or surgical intervention.3 Surgical treatment options are often challenging and carries significant risks, including high morbidity and mortality rates.4 Consequently, re-operation may not always be a feasible solution. Thus, minimally invasive treatment modalities have emerged as compelling alternatives to primary surgery.
Conventional non-surgical treatments, such as endoscopic fibrin glue injection, endoscopic clipping device, the over-the-scope clip, endoscopic suturing, and stenting (i.e., self-expanding plastic stents [SEPS] and self-expanding metal stents [SEMS]), provided feasible therapeutic options for anastomotic leaks (ALs), but have been associated with less favorable outcomes.2,5 While fibrin glue injection, clipping, and endoscopic suturing are suitable for early detection of small defects and stable patient conditions, their utility diminishes when dealing with larger or asymmetrical leaks.1,2,4 Also, stenting presents issues such as dislocation, stent extraction failure due to tissue in-growth, or secondary strictures.6,7 Moreover, both SEMS and SEPS hindered proper inspection of AL walls and wound cavities, thereby complicating the determination of optimal removal times.
Endoscopic vacuum therapy (EVT) has emerged as a pivotal advancement in endoscopic management for GI transmural defects over the last two decades.4,8 Initially developed to address AL after rectal surgery, its application has since expanded significantly, demonstrating remarkable success in treating lesions across the GI tract, including those in the esophagus, stomach, small bowel, and colorectal regions.9-15 Drawing inspiration from the foundational principles of negative pressure wound therapy, EVT operates through a variety of mechanisms, including micro-/macrodeformation, exudate management, and bacterial load reduction.16,17 This multifaceted approach allows EVT to meet a critical need in managing complex GI transmural defects, whether with or without extraluminal contamination.18 As a result, EVT stands out as a transformative strategy in the management of this GI tract condition.
In this review, we aimed to provide a review of EVT applications for GI transmural defects, offering insights into its current landscape in gastroenterology. As the role of EVT in GI treatment continues to evolve, its optimization and understanding are imperative for realizing its full therapeutic potential.
PRINCIPLES OF EVT
EVT operates by creating a negative pressure environment within the wound, which aids in shrinking and cleansing the wound as well as promoting the growth of granulation tissue.8 Furthermore, EVT boosts microcirculation and increases oxygen saturation through angiogenesis (Fig. 1).8,19
Principles of endoscopic vacuum therapy (EVT).
Delving into the intricate mechanisms of healing, EVT employs macrodeformation by applying suction to draw defected edges together, thereby significantly reducing sponge volume and effectively shrinking the defect.20,21 Microdeformation induces microscopic mechanical changes that initiate signaling cascades, thus promoting cell proliferation, migration, and expression of healing components.17,20,21 Additionally, EVT enhances perfusion by increasing microvessel density and promoting angiogenesis, thereby facilitating improved blood flow to the wound site.20,22 Fluid management is optimized as EVT effectively controls the exudate, removing fluid accumulation that impedes healing and fostering a clean wound environment conducive for tissue repair.8,16,20-22 While EVT addresses bacterial contamination, its impact remains a matter of debate, with some studies indicating a decrease in bacterial load and improved wound healing, while others presenting conflicting results.23
INDICATIONS AND CONTRAINDICATIONS OF EVT
The accurate identification of candidates for EVT is crucial to optimize its effectiveness. The existing literature primarily focuses on the application of EVT in treating AL after various GI surgeries, including oncologic resections and bariatric procedures as well as iatrogenic and spontaneous GI perforations occurring at sites such as the esophagus, stomach, and rectum.9,10,13,14,24 Additionally, EVT is promising for the management of other clinical scenarios, such as duodenal wall defects and pancreatic fistulas.11,25,26 EVT may be administered as a standalone intervention or in conjunction with surgical or radiological approaches.
In practice, consideration should be given to two EVT versions, intraluminal and intracavitary, which can be utilized independently or in combination (Fig. 2). In intracavitary EVT, a short open-pore element is inserted into the extraluminal cavity through a wall defect. Intracavitary EVT is suitable for the treatment of endoscopically accessible, extraluminal wound cavities. For minor defects (<10 mm), small-caliber endoscopes are initially used for assessment, and infected cavities may require dilation for open-pore, polyurethane foam-based drain (OPD) insertion.27 For uninfected small cavities, a small-lumen, open-pore film drain (OFD) or intraluminal EVT with an OPD can be used.27
Open-pore, polyurethane foam-based drain (OPD) tubes. (A) OPD cavity type. (B) OPD luminal type.
Defects and cavity size are crucial factors in planning the initial application and duration of therapy. There were no absolute contraindications based on the size alone. One study demonstrated the feasibility of employing EVT in managing cavities >7 cm and extending up to 15 cm.28 However, it is important to note that using a sponge with a diameter >3 cm can pose challenges for safe navigation through the esophagus or rectum.29
The timing of EVT initiation is also important, and early intervention is a significant determinant of therapeutic efficacy. In a case series focusing on acute iatrogenic perforations arising from endoscopic procedures, a remarkable 100% success rate was documented.30 This outcome was in part attributed to the swift detection of perforations and prompt initiation of treatment within a 24-hour window for all cases.30
However, despite its efficacy, EVT is limited to specific anatomical locations. With lesions located in certain areas, such as the proximal esophagus, hypopharynx, and gastric regions, particularly those in the fundus and corpus, the effectiveness of EVT remains challenging.18,29 Furthermore, EVT may not be appropriate for cases requiring restoration of GI tract continuity, such as complete anastomotic dehiscence or GI conduit necrosis.18,21,29
Although EVT plays a crucial role in stabilizing hemodynamically compromised patients by effectively controlling the infection sources in certain scenarios, surgical intervention may still be necessary if with inadequate response. Furthermore, when selecting candidates for EVT, careful consideration is needed in cases involving major blood vessels or the tracheobronchial system.27,29 Special attention is also warranted for patients receiving anticoagulant therapy because of the increased risk of bleeding.
In summary, meticulous patient selection is paramount for the successful application of EVT for GI transmural defects. Although EVT holds promise for favorable outcomes in the treatment of various GI conditions, further research is needed to precisely define the criteria for identifying ideal candidates.
DEVICES AND PROCEDURES
Equipment
Endoscope selection: A standard gastroscope is preferred for EVT because of its flexibility and minimal trauma.27
Open-pore drainage elements: These elements are attached to the distal end of the drainage tube by using sutures. There are two types of open-pore elements:
1) OPD
EVT employs polyurethane sponges, preferably macroporous and with low density, for enhanced debridement and wound contraction. In clinical practice, OPDs are tailored to the specific needs of a procedure. Typically, shorter systems with sponges measuring <5 cm are ideal for intracavitary EVT, whereas longer systems (>5 cm) are preferred for intraluminal therapy. Details on the preparation of the OPD device are provided in the procedural section below. Commercially available options, such as Eso-SPONGE (B. Braun Melsungen AG) and Suprasorb CNP endo (Lohmann & Rauscher), offer standardized insertion sets, thereby facilitating ease of use.
2) OFD
Pioneered by Loske et al.31 (Fig. 3), OFDs utilize a very thin, open-pore, double-layered drainage film, commercially known as Suprasorb CNP Drainage Film (Lohmann & Rauscher International GmbH & Co. KG). This film was smaller in caliber and exhibited reduced adherence to the wound cavity. OFDs can be used alone or in combination with polyurethane foam to enhance results.
Open-pore, film drain (OFD) construction. The illustration shows the material and construction steps for producing a basic type of OFD, with a diameter of only 5 mm. The transparent, thin, open-pore, double-layered drainage film (oF) consists of two multiple, perforated membranes, with a tiny space between the two membranes. The oF is wrapped around the distal end of a drainage tube (T) with lateral perforation openings (lP) and fixed in place with a suture (S). Loop (L) at the distal end of the OFD. For endoscopic vacuum therapy, the negative pressure is applied to the entire surface of the OFD along the T with an electronic vacuum pump. Photo by Professor Gunnar Loske (Department for General, Abdominal, Thoracic and Vascular Surgery, Katholisches Marienkrankenhaus Hamburg gGmbH, Hamburg, Germany).
Electronic pumps and negative pressure systems: Machines with variable negative pressures are available, featuring the continuous monitoring of relevant parameters. The optimal treatment duration and negative pressure may vary, thus must be determined empirically. Negative pressure levels between 75 and 150 mmHg are effective in promoting visible tissue granulation, with sponge removal usually posing no issues.8,19,27,32
Drainage tubes (nasogastric or nasojejunal) and sutures were used to fix open-pore drainage elements around the tube. Overtube (optional): A longer overtube can facilitate direct sponge insertion into the cavities or lumens, whereas a shorter one can cover the mouth, pharynx, and upper esophageal sphincter.32
Evaluation of GI tract dehiscence
Accurate exploration of the GI tract is essential for determining the appropriate procedures and instruments. Radiological and endoscopic imaging are the most effective methods of evaluating defects and extraluminal contamination. The assessment should involve measurements such as the distance from anatomical landmarks (i.e., the row of teeth or dentate line), as well as evaluate factors such as diameter, shape, and margins. Additionally, exploration of the abscess cavity is crucial. Endoscopy should be used diagnostically and therapeutically, whenever possible.
Procedures
The following steps outline the EVT procedure using an OPD in the upper GI tract (Fig. 4). For EVT in the lower GI tract, a similar approach using transrectal endoscopic drainage was adopted.
Schematic diagram of the endoscopic vacuum therapy procedure. OPD, open-pore, polyurethane foam-based drain.
1) Step 1: OPD tube preparation
Reinforce the sponge at the end of a drainage tube with a thread; insert a reinforced needle through the distal end of the sponge and the distal part of the tube, and then knot and cut it to leave thread tails approximately 1 cm in length. Trim the sponge to match the specific requirements of the system; a diameter of approximately 1.5 cm or one that covers more than half of the anastomosis circumference is usually suitable.27 For intracavitary EVT, a sponge length <5 cm is ideal. For intraluminal therapy, sponges >5 cm and up to 12 cm are preferred to ensure full coverage of the defect area or anastomosis.27 Finally, wrap the sponge at the end of the OPD tube with a transparent adhesive film.
2) Step 2: navigating the OPD tube through the nasal passage
Use a guidewire or a soft tube, such as an oxygen cannula, to create a loop. Insert the loop through the mouth, while the OPD tube through the nasal passage. Advance until the tip of the OPD tube reaches the desired location within the loop. The tip of the OPD tube is grasped through the oral cavity and gently pulled back.
3) Step 3: OPD tube insertion
Unfurl the transparent adhesive film at the OPD tube. Using a grasper or forceps, hold the distal end of the OPD tube at the threaded tail and guide it along the endoscope. Then, insert both the endoscope and OPD tube into the esophagus.
4) Step 4: place the sponge in proper position
Insert the OPD tube until the sponge reaches the defect location, ensuring proper placement either intra- or extraluminally as needed. Check the position of the sponge and make any necessary corrections. During this process, the location of the sponge is estimated by measuring the length of the drainage tube fixed to the nostril. This approach allowed for an initial assessment of the position of the sponge. The length of the tube is carefully monitored, and caution is exercised when withdrawing the endoscope to avoid simultaneous removal of the Levin tube. To ensure accurate placement, an X-ray is performed post-procedure to confirm the precise positioning of the sponge and to ensure EVT efficacy.
5) Step 5: initiate the negative pressure
Gently withdraw the endoscope, and ensure that the OPD tube is securely in-place. Then, connect the tube to a vacuum pump and initiate negative pressure.
Sponge replacement and evaluation
Sponges are changed every 3 to 5 days, with the leak site undergoing endoscopic evaluation to assess for healing progression. If the sponge is tightly adherent, requiring a significant force for removal, the suction should be turned off for 24 hours, thereby allowing the tissue to detach from the foam. Thereafter, subsequent removal attempts are typically easier.27 Complete therapy is determined by either closure of the leak or formation of granulation tissue.
Special considerations
1) Esophagus
In addressing complications associated with esophagectomy, pre-emptive EVT has the potential to prevent ALs and reduce morbidity in high-risk patients.33-35 Regarding the procedure, an intraluminal sponge is endoscopically inserted after anastomosis completion. The central portion of the sponge is positioned precisely at the anastomosis site. The OPD is then passed trans-nasally and connected to a vacuum pump.34
Considering the positioning of the sponge, as outlined in the indications section, if there is no contamination outside the luminal area, inserting the EVT device solely within the lumen is usually sufficient. However, in cases of extraluminal abscess or transmural ischemia, a multidisciplinary approach is required. It is crucial to acknowledge the potential risks associated with placing EVT devices extraluminally in the mediastinal compartment, such as hemorrhage and bronchopulmonary fistula, particularly when the abscess cavity lies near major vascular structures or airways. Thus, encasing the sponge with a non-adherent, permeable foil (e.g., drainage film) is recommended to mitigate these risks during extraluminal EVT.
It is important to note that OFDs play a significant role in treating esophageal defects by addressing the limitations of OPDs. Their small size and smooth surface allow for easier insertion and placement in the narrow esophageal lumen, thus reducing the risks of tissue adherence and complications during removal.36 Additionally, OFDs can be left in-place for longer periods, thereby minimizing the need for frequent endoscopic procedures. Its application in pre-emptive EVT shows promise in preventing post-operative ALs and potentially improving patient outcomes after high-risk esophageal surgeries.36
2) Stomach (sleeve gastrectomy)
The intracavitary vacuum therapy procedure follows a protocol similar to that described previously. In intraluminal therapy, an OFD is created by wrapping a thin film around the gastric segment of the nasojejunal feeding tube. The OFD device is then inserted intraluminally into the gastric sleeve, covering the leak area with a minimum 2-cm overlap of the healthy stalline sector in both the proximal and distal directions. The distal portion of the tube is used for enteral feeding.24,37,38
In certain instances, an additional procedure may involve the injection of 100 units of botulinum toxin diluted in 10 mL saline into the pylorus. This procedure aims to reduce pressure within the gastric cavity.37
3) Duodenum
Both OPD and OFD are suitable for use as open-pore drainage elements in the duodenum. During this process, pyloric dilatation may be necessary to facilitate sponge passage.11,39
In some cases, additional treatments involving the placement of a feeding tube should be considered. One option involves endoscopically placing a double-lumen, nasogastric feeding tube or a triple-lumen, diverted, nasogastric feeding tube, either before or after the primary intervention. The gastric lumen alleviates pressure in the duodenal region and manages gastric reflux, while enteral nutrition is delivered through the duodenal lumen. If tolerated, the nasojejunal tube is retained in place until successfully resolving the defect.11
4) Rectum
In the context of using EVT to manage anorectal AL, direct endoscopic necrosectomy is performed if tissue fragments adhere to the abscess wall during sponge changes. This procedure involves inserting an endoscope into the abscess cavity through the leakage site and removing necrotic tissue fragments by using a dormia basket or snare. After the necrosectomy, a new drainage tube is then introduced.40,41
RISK FACTORS FOR FAILURE OF THE EVT PROCEDURE
Several factors contribute to EVT failure. Patient-related factors, such as comorbidities (e.g., diabetes and immunosuppression), poor nutritional status, and advanced age, may impair healing.42 Infections, particularly severe or persistent ones at the wound site, also pose significant risks to EVT effectiveness.42
Wound characteristics include size, complexity, chronicity, and impact outcomes. Larger, complex, or chronic wounds, especially in challenging anatomical areas, may not respond well to EVT.29 Technical issues, such as inadequate sponge seals, incorrect placement, and frequent dislodgement, can compromise the therapy results. Finally, patient non-compliance can also hinder outcomes.
OUTCOMES OF EVT ON GI TRACT DEFECTS
Numerous clinical studies have consistently highlighted the positive outcomes of EVT, with success rates of >80% in achieving effective wound closure across various GI tract conditions.3,26,37-41,43-45 Furthermore, EVT reduces complications, shortens hospital stays, and lowers morbidity rates as compared to other methods.3,26,37-41,43-45
Recent meta-analyses have provided comprehensive insights into the pivotal role of EVT in the management of transmural GI tract defects (Table 1).9,10,13,40 Focusing on upper GI tract transmural defects, the latest meta-analyses by Jung et al.13 and Mandarin et al.9 have highlighted the efficacy of EVT and its superiority over stenting. This superiority enables regular wound monitoring, effective septic focus control, and adaptable therapy, while also significantly reducing adverse events as compared with stenting. In the context of gastric leaks post-bariatric surgery, Intriago et al.10 reported a remarkable clinical success rate of 87.2% with EVT, albeit moderate adverse events and system dislodgements were observed. Similarly, Kühn et al.’s meta-analysis40 on EVT for colorectal defects revealed a mean success rate of 81.4%, with manageable complication rates.
Latest meta-analyses on the role of endoscopic vacuum therapy in managing gastrointestinal tract defects
Furthermore, EVT has been proven efficacious in addressing specific conditions such as duodenal defects, achieving a definitive closure rate of 80% without severe adverse events,11,39 as well as rectal stump leaks, achieving a high success rate and leading to significant clinical improvement in the majority of patients.40 Additionally, several case reports and small series have highlighted the versatility of EVT in managing challenging situations arising from various upper GI defects. These include pancreaticogastric ALs,25,26 necrotizing pancreatitis,46 and ischemia of the blind jejunal loop post-gastrectomy.47 For instance, in cases of necrotizing pancreatitis, EVT serves as a supportive method for transgastric necrosectomy, especially when conventional treatments yield limited benefits.
An innovative and promising approach involves employing EVT in a pre-emptive context. Pre-emptive EVT has the potential to reduce the occurrence of ALs and associated morbidities by facilitating primary healing at the anastomotic site. Recent studies have underscored the clinical efficacy and feasibility of pre-emptive EVT in high-risk patients undergoing esophagectomy.33-35 There is great anticipation for the forthcoming results of a randomized controlled trial comparing pre-emptive EVT with standard post-operative care.48 These findings are eagerly awaited, with high expectations for their potential impact and insights.
Despite its efficacy, EVT is associated with certain complications, including bleeding, post-EVT strictures, sponge dislocation, and patient discomfort. However, most complications are manageable; for example, post-EVT strictures occur in 14% of cases,13 all of which are easily resolved through endoscopic dilatation. The most serious complication associated with EVT is massive bleeding, which may arise from fistulas between the cavity and major vessels or from the rupture of pseudo-aneurysms near vessels or heart chambers. The implementation of more frequent sponge changes may mitigate the risk of severe bleeding, particularly in cases of intracavitary therapy. Additionally, a review of computed tomography scans is essential to rule out vascular complications prior to initiating intracavitary EVT.
CHALLENGES AND LIMITATIONS
Risk of complications: EVT has inherent risks, particularly major bleeding. Although this complication is relatively uncommon, vigilant monitoring and prompt intervention are required to mitigate the adverse outcomes.
Patient tolerance and compliance: EVT often requires the placement of devices through the nose or rectum, which can lead to patient discomfort or inconvenience. Thus, ensuring patient tolerance and compliance throughout extended treatment periods can pose challenges, potentially influencing treatment effectiveness.
Limited evidence in certain indications: While EVT has demonstrated efficacy in specific clinical scenarios, evidence supporting its use in certain indications, such as huge perforations, defects with extensive tissue loss, post-operative pancreatic fistulas, and biliopancreatic defects, remains limited. Further studies are required to elucidate the optimal role of EVT in such challenging cases.
Standardization and training: The lack of standardized protocols and guidelines for EVT procedures may contribute to its variability in practice and outcomes. Adequate training and credentials of healthcare providers performing EVT are essential to ensure procedural safety and efficacy.
FUTURE PERSPECTIVES
Ongoing technological progress has led to the development of various EVT devices, including stent-over-sponge (SOS) or VACstent (Möller Medical GmbH).49 The SOS system integrates sponges with covered SEMS, significantly expanding the possibilities for EVT applications, notably in the management of complex ALs and pancreatic fistulas.50-52 Further investigations, including controlled-case, multicenter, longitudinal studies, may be necessary to ensure the efficacy of the SOS system in effectively managing such challenging conditions.
Another significant area of exploration is the pre-emptive use of EVT to reduce AL rates and overall morbidity after major foregut surgery. Although promising, further research is still required to determine its role for these indications.
Furthermore, there is a crucial need to refine the patient selection criteria and to establish standardized protocols, guidelines, and training programs for EVT practitioners. Collaborative efforts are essential for optimizing EVT utilization and patient care outcomes.
CONCLUSIONS
EVT has emerged as a promising avenue for managing GI transmural defects, representing a paradigm shift towards organ-preserving, minimally invasive interventions, even in scenarios that traditionally require major surgical procedures. The increasing use of EVT has demonstrated its effectiveness, both as a primary treatment and a salvage option following failed interventions. Despite its efficacy, it is crucial to acknowledge the complications associated with the procedure, primarily those related to major bleeding. Therefore, close monitoring for potential adverse events is imperative to ensure patient safety. Embracing EVT within an interdisciplinary framework can enhance patient care and pave the way for further advancements in this field.
Notes
Conflicts of Interest
The authors have no potential conflicts of interest.
Funding
None.
Author Contributions
Conceptualization: TML, SWJ; Data curation: SWJ; Formal analysis: TML; Investigation: SWJ, VHT; Methodology: KSC; Project administration: VHT; Resources: SWJ; Supervision: VHT, KSC; Validation: SWJ; Visualization: TML; Writing–original draft: TML; Writing–review & editing: all authors.