Short-term outcomes in mesh versus suture-only treatment of burst abdomen: a case-series from a university hospital
- Open Access
- 01.12.2025
- Original Article
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Abstract
Background
In midline laparotomy, a burst abdomen is a feared complication due to significant increases in patient morbidity and mortality [1‐4]. A rising number of studies and guidelines have sought to identify prophylactic interventions to reduce the incidence of burst abdomen, however, with diverging results [5‐11]. As such, rates of burst abdomen after midline laparotomy are reported to be 0–14% [11, 12].
The best approach to managing a burst abdomen remains inadequately defined due to sparse evidence [3]. Associated outcomes, including short-term issues such as wound complications and recurrent burst abdomen and long-term challenges such as incisional hernia development and diminished quality of life, are well known [1, 2, 13‐15]. Incisional hernia formation has been reported in up to 83% of patients after a burst abdomen [14, 16‐21]. Patients with incisional hernias often require complicated surgical procedures with the affiliated risk of chronic pain, reduced physical performance, low quality of life, and a notable risk of recurrence, necessitating further surgical hernia repair [22‐25].
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Mesh augmentation is arguably the one measure that could accommodate the risk of incisional hernia formation. Yet, the use of prophylactic meshes, especially in emergency surgery, carries the worry of mesh-related complications and has kept the introduction at bay [3, 26]. Within the last decade, a rising number of studies have suggested that prophylactic mesh augmentation in emergency laparotomy might be safe and probably deliver a long-term increase in hernia-free survival. Although surgical site occurrences seems to increase with mesh application in the emergency laparotomy, reported in up to 20.6% of the cases, partial or total mesh removal is only reported in few studies with a rate of 2.8-3.2% [12, 14, 16‐20, 27]. However, data are scarce, and methods and outcomes have been heterogeneous [28].
We hypothesized that mesh augmentation in surgery for a burst abdomen is safe in selected patients. This study aims to report the 90-day outcomes of patients treated for burst abdomen with or without a prophylactic mesh as a supplement.
Methods
This single-center cohort study was based on prospective registration of patients undergoing emergency surgery in a local database. The study was approved by the Danish Data Protection Agency and the capital region of Denmark (P-2020-1166, R-21038079, P-2921-533). As it was purely observational, without any intervention or randomization of patients, the Danish Research Ethics Committee did not require approval. The study was reported by the Reporting of Observational Studies in Epidemiology (STROBE) statement [29].
Setting
The study was conducted in the surgical section of the Department of Gastrointestinal- and Hepatic Diseases, Copenhagen University Hospital Herlev, a university hospital treating emergency admittances from an area covering 465,000 patients. The department consists of subspecialized surgical teams, including an emergency surgical team solely performing emergency surgical and endoscopic procedures. The department has a well-described strategy towards high-risk emergency surgical patients, including standardized pre- [30], intra- [31], and postoperative [32] frameworks, including documented standards for abdominal wall closure [11], the use of open abdomen strategies [33, 34], and surgical treatment of burst abdomen [2].
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Data collection and management
Data was recorded prospectively until discharge in all patients undergoing emergency laparotomy due to major pathology, including bowel obstructions, bowel perforations, ischemia, and intraperitoneal bleedings, as well as re-operations of both emergency- and elective cases. Data was collected via an electronic journal system (EPIC Hyperspace, Epic Systems Corp 2020) and stored in a REDCap database [35].
The database includes preoperative data on demographics, comorbidities, height, weight, tobacco- and alcohol consumption, American Association of Anesthesiologists (ASA) score, and World Health Organization (WHO) performance status. Intraoperative data included indication for surgery, type of procedure (both for index procedures and later re-operations), and specific documentation for abdominal wall closure. Peritoneal contamination was classified by the Center for Disease Control and Prevention (CDC) classification scale (1: clean, 2: clean-contaminated, 3: contaminated, and 4: dirty) [36]. Postoperative collected data consists of medical and surgical complications, including specific data collection on wound complications and postoperative death. Complications are scored by the Clavien-Dindo (CD) system for grading complications [37].
Participants and outcomes
All adult patients (≥ 18 years) undergoing surgery for a burst abdomen after midline laparotomy from the 1st of January 2021 to the 31st of December 2023 were evaluated.
Burst abdomen was defined as acute rupture of the sutured midline aponeurosis and was diagnosed either by visual inspection of the wound with visible bowel and/or omentum in the wound or, without concomitant skin-rupture, by re-opening of the skin-closure on the suspicion, typically caused by large amounts of fluid discharge through the skin closure [2, 3].
The primary outcome was the frequency of overall wound complications in the first 90 days after surgery for a burst abdomen, stratified by mesh augmentation in midline laparotomies. Secondary outcomes were rates of specific wound complications, including the need for mesh explantation, length of stay, and mortality rates.
Identification, registration, and classification of wound complications
Identification and registration of wound complications were performed by senior emergency surgeons, who managed the daily ward rounds for these patients. Data was recorded prospectively until discharge, and retrospectively from discharge until the 90th postoperative day. We defined short-term wound complications as any surgical site occurrence [38] within the first 90 days after surgery for a burst abdomen, including:
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Superficial infection, being an infection involving only the skin and subcutaneous tissue, and diagnosed by either discharge of pus from the wound without visualization of the sutured aponeurosis and/or mesh or treatment for a clinically diagnosed superficial wound infection [39].
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Deep infection, being an infection involving the deep soft tissues of the incision including the sutured aponeurosis and/or mesh, and diagnosed by pus, an abscess or other evidence of infection [39].
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Hematoma and Seroma, diagnosed either upon re-opening of the wound, by clinical diagnosis, or by radiologic imaging.
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Superficial wound dehiscence, diagnosed upon wound inspection as defects of the skin-closure after removal of sutures/staples without any signs of the above-mentioned wound complications.
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Re-dehiscence, being a recurrence of burst abdomen after surgical treatment for this complication and is otherwise defined as above.
Abdominal wall closure and the strategy for treatment of burst abdomen
The department has had continuously updated written standards since 2016 for both abdominal wall closure after primary laparotomy [11] and handling of burst abdomen [2], (Appendix A). Our center coheres to stringent indications for the use of open abdomen therapy as recommended by the World Society of Emergency Surgery [40] and has been previously described [34](Appendix B).
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Primary abdominal wall closure is performed with a 150 cm long, slowly absorbable polydioxanone suture size 2 − 0 mounted on a 28 mm needle, taking small 5–9 mm bites only of the midline aponeurosis, and suturing continuously with 5 mm between stitches resulting in a suture length to wound length ratio (SL: WL) of at least 4:1 [11].
Abdominal wall closure in the context of a burst abdomen is performed with a 150 cm long, slowly absorbable polydioxanone suture size 0 on a large CTX needle taking 3 cm large mass-closure bites of all layers (subcutaneous fat and skin excluded) continuously, with small steps of 5 mm between each stitch, resulting in a SL: WL of at least 10:1 (Fig. 1) [2].
Fig. 1
Two patients treated for burst abdomen. With large intraabdominal volume and/or loss of fascial domain, intraabdominal draping, mesh-mediated traction (A) and negative pressure therapy (B) was applied to the wound. When fascial closure was possible, mass-closure continuous suturing was used (C). If no contraindications were identified, an on-lay synthetic, partial absorbable mesh was augmented (D)
The choice to initiate an open abdomen strategy as opposed to abdominal wall closure is only chosen in the clinical situations of (a) persistent and severe unstable physiology (hypotension, hypothermia, pH < 7.20 or coagulopathy), (b) the need for reassessment of bowel viability, (c) loss of abdominal wall domain and/or too much tension needed for aponeurotic adaptation, and (d) in the context of abdominal compartment despite all non-operative actions been initiated (full medical muscle-relaxation, drainage of fluid-collection, decompression of the stomach with a tube and the urinary bladder with catheter) [34].
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Techniques for open abdomen, mesh-mediated fascial traction, and timing of fascial closure included using a generic system for temporary abdominal closure, utilizing the Abthera (3 M) protective plastic dressing, and application of 125mmHg continuous negative pressure. Mesh-mediated fascial traction was applied if fascial closure was impossible at the first change of the abdominal dressing (Fig. 1). The mesh was usually removed when fascial closure was possible, and a new permanent mesh would be applied if indicated. Changes of dressings were done three times a week until a tension-free fascial closure was possible. If severe fibrotic bowel adherences to fascia or subcutaneous fat were identified, predicting a high risk of bowel injury and entero-atmospheric fistula formation, fascial closure was abandoned resulting in skin-only closure with the acceptance of a formation of an incisional hernia [33, 34].
Application of prophylactic mesh in patients treated for burst abdomen was recommended under certain circumstances, being adult patients (≥ 18 years) with a life expectancy of > 1 year, with no plans of future pregnancies. Wound contamination was only a relative contraindication, but in the context of suspected contamination, a subcutaneous vacuum dressing was applied, with changes of this dressing two times a week bedside until a clean wound and initiation of granulation through the mesh was allowing for skin-closure in local anesthesia. The mesh was placed onlay with a 3 cm overlap both laterally, cranially, and caudally, and was sutured to the fascia at its border, with single stitches of a non-absorbable, monofilamentous suture, size 2 − 0 with approximately 2 cm between stitches (Fig. 1). Mesh-type for both mesh-mediated traction and prophylactic onlay placement was a macroporous, partially absorbable synthetic mesh (Ultrapro, Ethicon).
Statistical analysis
Continuous data is presented as means with standard deviation (SD). Categorical data is presented as frequencies and percentages. Data distribution was assessed by visual inspection of histograms and QQ plots. Univariate analysis of categorical data was performed utilizing the Pearson χ2 test unless less than five observations were done, in which case Fisher’s exact test was applied. The mean of numerical data was compared using an independent t-test. All p-values are presented as two-sided, and values of ≤ 0.05 were considered to be statistically significant.
Results
Preoperative data is outlined in Table 1. Through the period, a total of 67 patients were identified with a burst abdomen after midline laparotomy. 47 patients (70%) were male. 38 patients (56%) were treated without a permanent mesh (suture-only group), and 29 patients (44%) were treated with a permanent mesh (mesh group) (Fig. 2). Only a few female patients were treated with a mesh, with 25 patients (86%) of the patients in the mesh group being males (p = 0.012). No differences were identified between the two groups regarding ASA score, WHO performance status, tobacco use, or alcohol consumption. More patients in the mesh group (9 of 29 patients, 31%) had a Body Mass Index of 30 kg/m2 or higher compared to patients in the suture-only group (5 of 38 patients, 13%; p=0.075). There was no difference in the characteristics of the index procedure before the event of a burst abdomen between the two groups, with 90% in the suture-only group vs. 79% in the mesh group being an emergency procedure (p=0.274). 28 of 67 patients (42%) had peritonitis at index surgery with no differences between the two groups.
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Table 1
Baseline characteristics of patients treated for a burst abdomen with a suture-only technique or with supplemental mesh
Burst Abdomen N, total = 67(%) | ||||||
|---|---|---|---|---|---|---|
Suture only | Mesh | |||||
n = 38 | n = 29 | P | ||||
Sex, Male | 22 | (58) | 25 | (86) | 0.012 | |
Age, years | < 60 | 4 | (11) | 7 | (24) | .322a |
60–80 | 27 | (71) | 18 | (62) | ||
> 80 | 7 | (18) | 4 | (14) | ||
ASA-score | ≥ 3 | 14 | (47) | 14 | (48) | 0.347 |
WHO Performance status | ≥ 3 | 5 | (13) | 5 | (13) | 0.974 |
Body Mass Index | ≥ 30 kg/ m2 | 5 | (13) | 9 | (31) | 0.075 |
Active smokingb | 9 | (24) | 8 | (28) | 0.764 | |
Weekly alcohol consumption | > 10 units | 12 | (32) | 10 | (35) | 0.861 |
Previous midline laparotomy | 8 | (21) | 4 | (14) | 0.334 | |
Co-morbidities | Malignancy | 14 | (37) | 14 | (48) | 0.347 |
Cerebro-vascularc | 2 | (5) | 0 | (0) | .318a | |
Diabetes | 4 | (11) | 1 | (3) | .274a | |
Cardiacd | 14 | (37) | 14 | (48) | 0.347 | |
COPD | 3 | (8) | 3 | (10) | .526a | |
Chronic Renal Failure | 1 | (3) | 1 | (3) | .682a | |
Liver cirrhosis | 2 | (5) | 0 | (0) | .318a | |
Characteristics of index procedure | Emergency procedure | 34 | (90) | 23 | (79) | 0.274 |
Gastro-duodenal | 2 | (5) | 0 | (0) | .152a | |
Adhesiolysis | 7 | (18) | 1 | (3) | ||
Small bowel surgerye | 12 | (32) | 10 | (35) | ||
Large bowel surgerye | 17 | (45) | 18 | (62) | ||
Contamination | Peritonitisf | 18 | (47) | 10 | (35) | 0.289 |
CDC grade I | 3 | (8) | 6 | (21) | 0.303 | |
CDC grade II | 17 | (45) | 13 | (45) | ||
CDC grade III | 7 | (18) | 2 | (7) | ||
CDC grade IV | 11 | (29) | 8 | (27) | ||
Fig. 2
Flowchartof the study population and groups including patients treated consevartively for a burst abdomen (only skin-closure) and patientents with a course of temporaty abdominal closure before fascial closure
Surgical treatment of burst abdomen
Perioperative data from the surgery for burst abdomen is outlined in Table 2, and patients not having their fascia and/or skin closed at first re-operation are further schematized in Fig. 3. In the event of a burst abdomen, 13 of the 38 patients (34%) in the suture-only group suffered from peritonitis compared to four of the 29 patients (14%) in the mesh group (p = 0.051). Two of these four patients suffered from severe peritonitis (CDC grade IV). In the suture-only group, seven of 38 patients (18%) were treated without fascial closure, and only skin closure were performed. In six patients, this was due to severe fibrotic adherences, and in one patient, an entero-atmospheric fistula formed. In the last patient, fascial closure was impossible due to severe loss of domain in a patient deemed too frail to go through a series of operations with a prolonged open abdomen. All patients in the suture-only group, except patients who underwent conservative treatment, had their fascia closed at the first operation for a burst abdomen, while a mean delay of 3.3 days in the mesh group was seen (p = 0.01). Hence, temporary abdominal closure was only applied among patients in the mesh group (11 of 29 patients, 38%, p < 0.001). The mean SL: WL was comparable between the two groups (13:1 in the suture-only group vs. 14:1 in the mesh group, p = 0.39). All patients with delayed skin closure were treated with subcutaneous vacuum therapy; six of the 38 patients (16%) in the suture-only group vs. 20 of the 29 patients (69%) in the mesh group (p < 0.001).
Table 2
Perioperative characteristics for suture-only vs. mesh groups
Surgery for burst abdomen, intraoperative data N, total = 67(%) | ||||||
|---|---|---|---|---|---|---|
Suture only | Mesh | |||||
n = 38 | n = 29 | P | ||||
Days from index surgery to burst abdomen | Mean (SD) | 8.7 | (3.3) | 7.7 | (3.8) | .240 |
Degree of contamination | Overall peritonitisa | 13 | (34) | 4 | (14) | .051b |
CDC Grade II | 25 | (66) | 25 | (87) | .162b | |
CDC Grade III | 7 | (18) | 2 | (7) | ||
CDC Grade IV | 6 | (16) | 2 | (7) | ||
Days to fascial closure | Mean (SD) | 0 | (0) | 3.3 | (6.9) | 0.01 |
Days from fascial closure to skin closure | Mean (SD) | 0.62 | (1.4) | 4.4 | (3.8) | < 0.001 |
Conservative treatment | 7 | (18) | 0 | (0) | .015b | |
Temporary abdominal closure applied | 0 | (0) | 11 | (38) | < 0.001b | |
Subcutaneous VAC applied before skin closure | 6 | (16) | 20 | (69) | < 0.001 | |
Suture length to wound length ratio (if fascial closure) | Mean (SD) | 13 | (4.5) | 14 | (4.1) | 0.39 |
Fig. 3
Specific course and outcomes of the patients treated for burst abdomen with the need of temporary abdominal closure and/or subcutaneous vacuum treatment. Patients not included In the figure: 32 patients in suture-only group and 8 patients in mesh-group with immediate fascial and skin-closure.Sx, Patients within the suture-only group; Mx, Patients within the mesh-group; X, Mesh explantation; D, Death
There was no difference regarding age, BMI, comorbidities, or characteristics of the primary procedure between males and females. Seven of the 20 (35%) female patients and 10 of the 47 (21%) male patients suffered from peritonitis at the time of surgery for a burst abdomen (p = 0.237), while only two of the 20 (10%) female patients compared to 16 out of 47 (34%) male patients underwent a course of open abdomen treatment before having the fascia closed (p = 0.042).
Postoperative outcomes
Short-term wound complications after surgical treatment for a burst abdomen are outlined in Table 3. There were 36 wound complications in 67 patients, with no statistical differences between the two groups. Two recurrences of burst abdomen occurred in the non-mesh group, while no patients in the mesh group suffered from this. Within the mesh group, 14 of 29 patients (48%) suffered from a wound complication, with the majority of these being mild complications graded as Clavien-Dindo grade I (12 of 14 patients). One patient needed surgical treatment under general anesthesia (CD grade IIIb). This patient suffered from a deep wound infection 11 days after skin closure. The wound was initially reopened and treated with subcutaneous vacuum therapy aiming to obtain granulation tissue through the mesh. Yet, after six days and three dressing changes, this strategy was abandoned, and the mesh was surgically removed. The patient was discharged with a partially closed wound at the skin level and was followed on an outpatient basis, and complete secondary healing was obtained within three weeks.
Table 3
Comparison of short-term (90 days) wound complications after surgery for a burst abdomen in suture-only vs. mesh groups
Short term (90 days) wound complications N, total = 67(%) | ||||||
|---|---|---|---|---|---|---|
Suture only | Mesh | |||||
n = 38 | n = 29 | P | ||||
Type of complication | Overall | 22 | (58) | 14 | (48) | .174a |
Hematoma | 0 | (0) | 3 | (10) | ||
Seroma | 4 | (11) | 3 | (10) | ||
Superficial wound dehiscence | 7 | (19) | 5 | (17) | ||
Burst abdomen (recurrence) | 2 | (5) | 0 | (0) | ||
Entero-atmospheric fistula | 1 | (3) | 0 | (0) | ||
Superficial wound infection | 8 | (22) | 2 | (7) | ||
Deep (mesh) infection and explantation | NA | 1 | (3) | |||
Clavien Dindo grade of complication | 1 | 16 | (42) | 12 | (41) | .511a |
2 | 1 | (3) | 0 | (0) | ||
3a | 0 | (0) | 1 | (3) | ||
3b | 4 | (11) | 1 | (3) | ||
4 | 1 | (3) | 0 | (0) | ||
Length of stay, days | Mean (SD) | 22 | (13) | 27 | (13) | .08b |
Mortality | 30 days | 8 | (21) | 3 | (10) | .202a |
90 days | 9 | (24) | 5 | (17) | 0.52 | |
The mean length of stay was 22 days in the suture-only group compared to 27 days in the mesh group (p = 0.08). Mortality rates were comparable between the groups, with a 90-day mortality rate of 21% (14 of 67 patients) among all patients treated for burst abdomen in the study period.
Discussion
Between January 2021 and December 2023, we treated 67 patients for burst abdomen after midline laparotomy. To accommodate a well-known high risk of incisional hernia formation after treatment of this complication, our center initiated an option for mesh application before the study period [1, 3]. Of the 67 patients treated for burst abdomen, 29 (43%) were supplemented with a mesh. No differences in the rate or severity of wound complications between sutured-only patients and mesh-augmented patients were identified. Wound complications were common, with 53% of the patients (36 of 67 patients) suffering from any wound-related complication. However, 78% (28 of 36 complications) were minor complications with no need for surgical intervention. We registered four major surgical complications. Within the suture-only group, two patients suffered from recurrence of burst abdomen, and one patient developed an entero-atmospheric fistula. Within the mesh group, one out of 29 patients (3%) suffered from mesh infection with the need for mesh explantation which is comparable to similar studies [12, 16, 18, 19].
Risk factors for a burst abdomen are multiple and heterogeneous [2, 3, 19, 41‐45]. In our study, identifying risk factors for a burst abdomen was not possible due to the study design. However, we found that patients suffering from burst abdomen were often male (47 of 67 patients, 70%), had a high ASA score ≥ 3 (28 of 67 patients, 42%), and often suffered from comorbidities, including malignant diseases. Furthermore, most patients went through an emergency procedure before the event of a burst abdomen (55 of 67 patients, 82%). These findings are comparable to the literature and probably, at least to some extent, contribute to the high 90-day mortality rate of 21% (14 out of 67 patients) [11, 46‐48]. In this case series, mesh augmentation was more often chosen in case of a clean wound, obesity, and a preceding course of open abdomen. Our study is not designed to evaluate contraindications for mesh augmentation in detail, and although wound contamination was not an absolute contraindication, it seems reasonable that surgeons are cautious in case of a contaminated wound, knowing there is a risk of mesh infection [3, 26]. Obesity is a well-known risk factor for incisional hernia formation and, in combination with a burst abdomen, probably leaves a patient at high risk [49‐51]. We apply temporary abdominal closure whenever fascial adaptation is not possible due to excessive retraction of the fascia or increased abdominal volume, and only patients that underwent this treatment also received a mesh (0% in the suture-only group vs. 38% in the mesh group, p < 0.001). Patients undergoing open abdomen treatment potentially are more physiologically deranged, and edematous abdominal wall and/or abdominal wall necrosis in this context might stimulate the surgeon to apply a mesh based on an expectation that the risk of incisional hernia formation might be high [52, 53].
The treatment of burst abdomen is still debated and high morbidity- and mortality rates, high rates of recurrence, extended length of stay, and a remarkably high rate of incisional hernia formation are some of the challenges that need focus [1, 47]. Earlier, we documented that surgery for a burst abdomen with a suture-only strategy with a mass-closure technique produced low rates of recurrence, but the incisional hernia rate remained high at 33% with a median follow-up of 17 months (min 4, max 67 months), which is comparable to the literature [1, 2, 18, 19]. This understated the broadly recognized need for further actions toward hernia prophylaxis in patients treated for burst abdomen [3]. Prophylactic mesh augmentation has been a main topic in the debate. However, the hernia societies have not been able to clearly state when and how a surgeon should choose prophylactic mesh in laparotomies, due to only low-quality evidence [3, 26]. Mesh infection, with or without the need for mesh explantation, is a relevant and feared complication, and as of today, it is up to every surgeon and/or center to decide when prophylactic mesh should be considered. The patient presented in this study, with mesh infection and need of explantation, tolerated the complication well. However, the finding underscores the importance of the debate surrounding this type of surgical modality. Only a few studies investigate the effect of prophylactic mesh in surgery for burst abdomen [16, 18, 19]. The results suggest a reduction in incisional hernia formation compared to suture-only techniques. The studies are small and mostly of retrospective design, leaving a high risk of bias. However, the results align with the evidence in general regarding the benefits of prophylactic mesh augmentation in primary laparotomy in high-risk cases [54‐56]. It is important to further investigate risk profiles and profits of mesh augmentation in surgery for burst abdomen before proper guidelines with high-quality evidence can be designed. Our study only investigates short-term outcomes and long-term follow-up on this patient-cohort will reveal if our technique presents any benefits towards incisional hernia formation.
In this case-series we introduced a new algorithm to the treatment of burst abdomen, with the option of mesh-augmentation in the case of burst abdomen, which was applied in 44% of cases. Introduction of new surgical techniques, especially ones that in general are considered associated to an increased risk-profile, potentially can be met with resistance amongst surgeons. We cannot speculate in whether 44% is an appropriate rate of patients to receive a mesh and randomized trials comparing mesh-augmentation to a suture-only technique are needed.
Our study is limited to its design and sample size. The study is a non-randomized, single-center study and data is not necessarily generalizable. With 67 patients treated for burst abdomen, and a subgroup of 29 patients receiving mesh-closure, we cannot be sure that the results are not a product of a small sample size. However, burst abdomen is a rare complication and data at least suggest that mesh augmentation in the emergency setting of burst abdomen is relatively safe. This study investigates short-term outcomes regarding wound complications and cannot comment on long-term consequences, including the risk of hernia development. Further studies are needed regarding burst abdomen prophylaxis and regarding improvement of both short-term and long-term outcomes of patients suffering from burst abdomen.
In conclusion, mesh augmented closure of burst abdomen seems to be safe in well-selected patients, producing primarily mild wound complications comparable to suture-only techniques.
Acknowledgements
This paper is not based on previous communication to a society or meeting.
Declarations
Ethical approval
Approvals The study was approved by the appropriate institutions.
Conflict of interest
The authors declare that they have no conflict of interest.
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