The Danish Ventral Hernia Database - a valuable tool for quality assessment and research

Protocol for the AFTERHERNIA Project: patient-reported outcomes of groin and ventral hernia repair

PURPOSE

The AFTERHERNIA Project aims to shift the focus of hernia surgery towards patient-reported outcomes by examining the impact of surgical methods and long-term complications on a national level. Groin and ventral hernia repairs are common surgical procedures with significant impact on patient quality of life and healthcare costs. Most large-scale studies focus on clinical outcomes like reoperation and readmission rates, rather than patient-reported outcomes.

METHODS

This nationwide survey involves Danish patients who have undergone groin or ventral hernia repair over a ten-year period. Patients will be identified in the Danish National Patient Registry, and they will receive either the Abdominal Hernia-Q or Groin Hernia-Q questionnaire to collect data on patient-reported outcomes. Data from the questionnaire will be linked with clinical and patient-related data from the Danish Hernia Database. The Danish National Patient Registry also contains information on long-term surgical complications. Thereby, it will be possible to link specific perioperative details with patient-reported outcomes and long-term surgical complications.

CONCLUSION

The AFTERHERNIA Project aims to redefine the understanding of hernia surgery outcomes by emphasizing patient-reported outcomes on a nationwide basis. By capturing a broad spectrum of patient experiences and outcomes, the project expects to inform and possibly transform clinical guidelines and patient care practices.

Primary and incisional hernias should be considered separately in clinical decisions and research: A nationwide register-based cohort study

BACKGROUND

Ventral hernias of umbilical, epigastric, and incisional types pose varied surgical challenges. Recent debates and research suggest that treatment strategies and outcomes may vary significantly based on hernia type and width. This study investigated whether differences in the risk of surgical outcomes among primary and incisional hernias are solely due to the hernia type. The primary outcome was reoperation for recurrence, and the secondary outcome was 90-day postoperative readmission.

METHODS

This study was based on prospectively collected data from the Danish Ventral Hernia Database linked with the Danish Civil Registration system and the National Patient Register. Data spanned from 2007 to 2022 and included patients with umbilical, epigastric, or incisional hernias. The 3 hernia types were analyzed for the risk of reoperation for recurrence, adjusted for sex, age, emergency repair, width, use of mesh, and Charlson comorbidity index.

RESULTS

We included 57,312 hernias: 34,147 umbilical, 9,433 epigastric, and 13,722 incisional hernias. Compared with patients with umbilical hernias, patients with epigastric hernias had a lower risk of reoperation (hazard ratio: 0.88, 95% confidence interval: 0.79-0.99) and those with incisional hernias had an increased risk (hazard ratio: 2.93, 95% confidence interval: 2.57-3.33). Postoperative 90-day readmission rates were also higher for patients with incisional hernias than for patients with umbilical and epigastric hernias.

CONCLUSION

Incisional hernias exhibited a higher risk of reoperation for recurrence and 90-day postoperative readmission, underscoring their unique nature in terms of both origin and clinical behavior. The findings suggest that primary and incisional hernias should be separate entities in medical practice and research.

Repair of umbilical hernias concomitant to other procedures is safe: a propensity score-matched database study

BACKGROUND

Repair of an umbilical hernia is most often considered the less important condition when concomitant with other abdominal surgery. Despite this, the evidence for a concomitant umbilical hernia repair is sparse. The aim of this nationwide cohort study is to compare the short- and long-term outcomes of primary umbilical hernia repair and umbilical hernia repair concomitant with other abdominal surgery.

METHOD

Data from the Danish Hernia Database and the National Patients Registry from January 2007 to December 2018 was merged, resulting in identification of patients receiving umbilical hernia concomitant to another abdominal surgery (laparoscopic inguinal hernia repair, laparoscopic cholecystectomy, and laparoscopic appendectomy). This group was propensity score matched with patients undergoing umbilical hernia repair as a primary procedure. Outcome data included 90-day readmission, 90-day reoperation, and operation for recurrence.

RESULTS

A total of 3365 primary umbilical hernia repairs and 2418 umbilical hernia repairs concomitant to other abdominal surgery were included. Readmission (10.5%, 255/2418) and reoperation (3.8%, 93/2418) rates within 90 days were decreased for umbilical hernia repairs concomitant to other abdominal surgery, compared with primary umbilical hernia repairs (22.7%, 765/3365) and (10.5%, 255/3365), P < 0.001 and P < 0.001, respectively. The rate of operation for recurrence was significantly increased for primary repairs (4.2%, 141/3365), compared with repairs concomitant to other abdominal surgery (3.2%, 77/2418), P = 0.014.

CONCLUSION

Outcome in umbilical hernia repair performed concomitant to laparoscopic inguinal hernia repair, elective or emergency laparoscopic cholecystectomy, or laparoscopic appendectomy is comparable to umbilical hernia repair without concomitant surgery.

Lessons learnt from the construction and implementation of a prospective ventral hernia database

PURPOSE

The New England VA Hernia Registry was created in 2011 to prospectively collect relevant details of ventral hernia repairs, with the intention to assess and improve long term outcomes. The goal of this study is to assess registry compliance.

METHODS

All ventral hernia operations performed in five VA hospitals between 2011-2022 were obtained. We assessed compliance at the hospital and surgeon level.

RESULTS

3,516 cases were performed. Overall compliance with registry entry was 37.5%, ranging from 10.8% to 67.2% across hospitals. At the hospital level, there was a negative correlation between average yearly hernia volume per surgeon and registry compliance (r2 = 0.53). Surgeon compliance varied within hospitals and over time.

CONCLUSION

Registry compliance was low and highly variable. Lack of interest, incentives, oversight, and surgeon turnover are possible factors for noncompliance. Building a registry with these factors in mind, providing timely feedback, and conducting frequent audits may improve compliance.

Short-term outcomes after open versus robot-assisted repair of ventral hernias: a nationwide database study

PURPOSE

The robotic platform is widely implemented; however, evidence evaluating outcomes of robotic ventral hernia repair is still lacking. The aim of the study was to evaluate the short-term outcomes after open and robot-assisted repair of primary ventral and incisional hernias.

METHODS

Nationwide register-based cohort study with data from the Danish Ventral Hernia Database and the National Danish Patients Registry was from January 1, 2017 to August 22, 2022. Robot-assisted ventral hernia repairs were propensity score matched 1:3 with open repairs according to the confounding variables defect size, Charlson comorbidity index score, and age. Logistic regression analyses were performed for factors associated with length of stay > 2 days, readmission, and reoperation within 90 days.

RESULTS

A total of 528 and 1521 patients underwent robot-assisted and open repair, respectively. The mean length of hospital stay in days was 0.5 versus 2.1 for robot-assisted and open approach, respectively (P < 0.001) and open approach was correlated with risk of length of stay > 2 days (OR 23.25, CI 13.80-39.17, P < 0.001). The incidence of readmission within 90 days of discharge was significantly lower after robot-assisted repair compared to open approach (6.2% vs. 12.1%, P < 0.001). Open approach was independently associated with increased risk of readmission (OR 21.43, CI 13.28-39.17, P = 0.005, P < 0.001).

CONCLUSION

Robot-assisted ventral hernia repair is safe and feasible and associated with shorter length of stay and decreased risk of readmission compared with open ventral hernia repair.

Use of statewide financial incentives to improve documentation of hernia and mesh characteristics in ventral hernia repair

BACKGROUND

Documentation of intraoperative details is critical for understanding and advancing hernia care, but is inconsistent in practice. Therefore, to improve data capture on a statewide level, we implemented a financial incentive targeting documentation of hernia defect size and mesh use.

METHODS

The Abdominal Hernia Care Pathway (AHCP), a voluntary pay for performance (P4P) initiative, was introduced in 2021 within the statewide Michigan Surgical Quality Collaborative (MSQC). This consisted of an organizational-level financial incentive for achieving 80% performance on eight specific process measures for ventral hernia surgery, including complete documentation of hernia defect size and location, as well as mesh characteristics and fixation technique. Comparisons were made between AHCP and non-AHCP sites in 2021.

RESULTS

Of 69 eligible sites, 47 participated in the AHCP in 2021. There were N = 5362 operations (4169 at AHCP sites; 1193 at non-AHCP sites). At AHCP sites, 69.8% of operations had complete hernia documentation, compared to 50.5% at non-AHCP sites (p < 0.0001). At AHCP sites, 91.4% of operations had complete mesh documentation, compared to 86.5% at non-AHCP sites (p < 0.0001). The site-level hernia documentation goal of 80% was reached by 14 of 47 sites (range 14-100%). The mesh documentation goal was reached by 41 of 47 sites (range 4-100%).

CONCLUSIONS

Addition of an organizational-level financial incentive produced marked gains in documentation of intra-operative details across a statewide surgical collaborative. The relatively large effect size-19.3% for hernia-is remarkable among P4P initiatives. This result may have been facilitated by surgeons' direct role in documenting hernia size and mesh use. These improvements in data capture will foster understanding of current hernia practices on a large scale and may serve as a model for improvement in collaboratives nationally.

Short-term Outcomes After Laparoscopic IPOM Versus Robot-assisted Retromuscular Repair of Small to Medium Ventral Hernias: A Nationwide Database Study

OBJECTIVE

To examine the short-term outcomes after laparoscopic intraperitoneal onlay mesh (IPOM) compared with robot-assisted retromuscular repair of small to medium-sized ventral hernia.

BACKGROUND

With the introduction of a robot-assisted approach, retromuscular mesh placement is technically more feasible compared with laparoscopic IPOM, with potential gains for the patient, including avoidance of painful mesh fixation and intraperitoneal mesh placement.

METHODS

This was a nationwide cohort study of patients undergoing either laparoscopic IPOM or robot-assisted retromuscular repair of a ventral hernia with a horizontal fascial defect <7 cm in the period 2017 to 2022, matched in a 1:2 ratio using propensity scores. Outcomes included postoperative hospital length of stay, 90-day readmission, and 90-day operative reintervention, and multivariable logistic regression analysis was performed to adjust for the relevant confounder.

RESULTS

A total of 1136 patients were included for analysis. The rate of IPOM-repaired patients hospitalized > 2 days was more than 3 times higher than after robotic retromuscular repair (17.3% vs. 4.5%, P < 0.001). The incidence of readmission within 90 days postoperatively was significantly higher after laparoscopic IPOM repair (11.6% vs. 6.7%, P =0.011). There was no difference in the incidence of patients undergoing operative intervention within the first 90 days postoperatively (laparoscopic IPOM 1.9% vs. robot-assisted retromuscular 1.3%, P =0.624).

CONCLUSIONS

For patients undergoing first-time repair of a ventral hernia, robot-assisted retromuscular repair was associated with a significantly reduced incidence of prolonged length of postoperative hospital stay and risk of 90-day readmission compared to laparoscopic IPOM.

Epidemiology and surgical management of 184 obturator hernias: a nationwide registry-based cohort study

PURPOSE

We aimed describe the patient characteristics, surgical details, postoperative outcomes, and prevalence and incidence of obturator hernias. Obturator hernias are rare with high mortality and no consensus on the best surgical approach. Given their rarity, substantial data is lacking, especially related to postoperative outcomes.

METHODS

The study was based on data from the nationwide Danish Hernia Database. All adults who underwent obturator hernia surgery in Denmark during 1998-2023 were included. The primary outcomes were demographic characteristics, surgical details, postoperative outcomes, and the prevalence and incidence of obturator hernias.

RESULTS

We included 184 obturator hernias in 167 patients (88% females) with a median age of 77 years. Emergency surgeries constituted 42% of repairs, and 72% were laparoscopic. Mesh was used in 77% of the repairs, with sutures exclusively used in emergency repairs. Concurrent groin hernias were found in 57% of cases. Emergency surgeries had a 30-day mortality of 14%, readmission rate of 21%, and median length of stay of 6 days. Elective surgeries had a 30-day mortality of 0%, readmission rate of 10%, and median length of stay of 0 days. The prevalence of obturator hernias in hernia surgery was 0.084% (95% CI: 0.071%-0.098%), with an incidence of one per 400,000 inhabitants annually.

CONCLUSIONS

This was the largest cohort study to date on obturator hernias. They were rare, affected primarily elderly women. The method of repair depends on whether the presentation is acute, and emergency repair is associated with higher mortality.

Risk of Reoperation for Recurrence After Elective Primary Groin and Ventral Hernia Repair by Supervised Residents

Importance

Surgical training involves letting residents operate under supervision. Since hernia repair is a common procedure worldwide, it is a frequent part of the surgical curriculum.

Objective

To assess the risk of reoperation for recurrence after elective primary groin and ventral hernia repair performed by supervised residents compared with that by specialists.

Design, Setting, and Participants

This nationwide register-based cohort study included data from January 2016 to September 2021. Patients were followed up until reoperation, emigration, death, or the end of the study period. The study used data from the Danish Inguinal and Ventral Hernia Databases linked with data from the Danish Patient Safety Authority's Online Register via surgeons' unique authorization ID. The cohort included patients aged 18 years or older who underwent primary elective hernia repairs performed by supervised residents or specialists for inguinal, femoral, epigastric, or umbilical hernias. Hernia repairs were divided into the following 4 groups: Lichtenstein groin, laparoscopic transabdominal preperitoneal (TAPP) groin, open ventral, and laparoscopic ventral.

Exposures

Hernia repairs performed by supervised residents vs specialists.

Main Outcomes and Measures

Reoperation for recurrence, analyzed separately for all 4 groups.

Results

A total of 868 specialists and residents who performed 31 683 primary groin and 7777 primary ventral hernia repairs were included in this study. The median age of patients who underwent hernia repair was 60 years (IQR, 48-70 years), and 33 424 patients (84.7%) were male. There was no significant difference in the adjusted risk of reoperation after Lichtenstein groin hernia repair (hazard ratio [HR], 1.26; 95% CI, 0.99-1.59), laparoscopic groin hernia repair (HR, 1.01; 95% CI, 0.73-1.40), open ventral hernia repair (HR, 0.89; 95% CI, 0.61-1.29), and laparoscopic ventral hernia repair (HR, 2.96; 95% CI, 0.99-8.84) performed by supervised residents compared with those by specialists. There was, however, a slightly increased unadjusted, cumulative reoperation rate after Lichtenstein repairs performed by supervised residents compared with those by specialists (4.8% vs 4.2%; P = .048).

Conclusions and Relevance

The findings of this study suggest that neither open nor laparoscopic repair of groin and ventral hernias performed by supervised residents appeared to be associated with a higher risk of reoperation for recurrence compared with the operations performed by specialists. This indicates that residents may safely perform elective hernia repair when supervised as part of their training curriculum.

Outcomes After Spigelian Hernia Repair: A Nationwide Database Study

BACKGROUND

Spigelian hernia is a rare hernia of the abdominal wall. Due to lack of evidence, there is no standard recommendation for surgical technique of Spigelian hernia repair. The aim of this study was to evaluate the outcomes after open and laparoscopic, elective and emergency repair of Spigelian hernias on a nationwide basis.

METHODS

Nationwide data from the Danish Ventral Hernia Database and the National Patient Registry was assessed to analyze outcomes after Spigelian hernia repair. A total of 365 patients were operated for Spigelian hernia in Denmark from 2007 to 2018. Ninety-day readmission, 90-day reoperation and long-term operation for recurrence were evaluated, as well as possible differences between open and laparoscopic, and elective and emergency repairs.

RESULTS

Most of the patients (80.5%, 294/365) were operated by laparoscopic approach and 19.5% (71/365) were operated by open approach. Elective surgery was performed in 83.6% (305/365) of the patients and 16.4% (60/365) underwent emergency repair. There were no significant differences in 90-day readmission or reoperation rates between open or laparoscopic Spigelian hernia repairs, P = 0.778 and P = 0.531. Ninety-day readmission and 90-day reoperation rates were also comparable for elective versus emergency repair, P = 0.399 and P = 0.766. No difference was found in operation for recurrence rates between elective and emergency, nor open and laparoscopic Spigelian hernia repairs.

CONCLUSIONS

This study demonstrates that 16% of Spigelian hernia repairs are done in the emergency setting. Open and laparoscopic approach are comparable in terms of early readmission, reoperation, and recurrence rates.

Reoperation for Recurrence is Affected by Type of Mesh in Laparoscopic Ventral Hernia Repair: A Nationwide Cohort Study

OBJECTIVE

To compare the reoperation rate for recurrence between different mesh types in laparoscopic ventral hernia repair.

SUMMARY OF BACKGROUND DATA

Ventral hernia repair has improved over the last decades. Nevertheless, recurrence rates are still high, and one type of mesh was recently found to increase it even more.

METHODS

A nationwide cohort study based on prospectively collected data from the Danish Ventral Hernia Database. We included adult patients that had undergone a laparoscopic ventral hernia repair for either an incisional or a primary hernia. The primary and incisional hernias were analyzed in separate cohorts. The mesh-group with the lowest reoperation for recurrence curve was used as the reference. The outcome was reoperation for recurrence.

RESULTS

Study population comprised 2874 patients with primary hernias and 2726 with incisional hernias. For primary hernias, Physiomesh [HR = 3.45 (2.16-5.51)] and Proceed Surgical Mesh [HR = 2.53 (1.35-4.75)] had a significantly higher risk of reoperation for recurrence than DynaMesh-IPOM. For incisional hernias, Physiomesh [HR = 3.90 (1.80-8.46), Ventralex Hernia Patch (HR = 2.99 (1.13-7.93), Parietex Composite (incl. Optimized) (HR = 2.55 (1.17-5.55), and Proceed Surgical Mesh (HR = 2.63 (1.11-6.20)] all had a significantly higher risk of reoperation for recurrence than Ventralight ST Mesh.

CONCLUSION

For primary hernias, Physiomesh and Proceed Surgical Mesh had a significantly higher risk of reoperation for recurrence compared with DynaMesh-IPOM. For incisional hernias, the risk was significantly higher for Physiomesh, Parietex Composite, Ventralex Hernia Patch, and Proceed Surgical Mesh compared with Ventralight ST Mesh. This indicates that type of mesh may be associated with outcomes, and mesh choice could therefore depend on hernia type.

Outcomes of parastomal hernia repair after national centralization

BACKGROUND

In 2010, it was decided to centralize parastomal hernia repairs to five specialized hernia centres in Denmark to improve outcomes. The aim of this nationwide cohort study was to evaluate whether centralization of parastomal hernia repairs has had an impact on outcomes. Specifically, readmission, reoperation for complication, and operation for recurrence were analysed before and after centralization.

METHODS

By merging clinical and administrative outcome data from the Danish Hernia Database with those from the Danish National Patient Registry, all patients undergoing parastomal hernia repair in Denmark from 1 January 2007 to 31 December 2018 were included. Centralization was defined as having at least 70 per cent of procedures were performed at one of the five national centres. Readmission, reoperation, and recurrence rates for emergency and elective repairs were evaluated before and after centralization.

RESULTS

In total, 1062 patients were included. Median follow-up was 992 days. Overall, the centralization process took 7 years. For elective repairs, the readmission, reoperation, mortality, and recurrence rates were comparable before and after centralization, but more patients overall and more patients with co-morbidity were offered surgery after centralization. For emergency repairs, there was a significant reduction in rates of reoperation (from 44.9 per cent (48 of 107) to 23 per cent (14 of 62); P = 0.004) and mortality (from 10.3 per cent (11 of 107) to 2 per cent (1 of 62); P = 0.034) after centralization.

CONCLUSION

Centralization led to more elective operations and better outcomes when emergency repair was needed. Centralization of parastomal hernia repair led to more patients receiving elective repair and significantly improved outcomes after emergency repair.

Surgeon Volume and Risk of Reoperation after Laparoscopic Primary Ventral Hernia Repair: A Nationwide Register-Based Study

BACKGROUND

Repairs of primary ventral hernias are common procedures but are associated with high recurrence rates. Therefore, it is important to investigate risk factors for recurrence to optimize current treatments. The aim of this study was to assess the impact of annual surgeon volume on the risk of reoperation for recurrence after primary ventral hernia repair.

STUDY DESIGN

We conducted a nationwide register-based study with data from the Danish Ventral Hernia Database and the Danish Patient Safety Authority's Online Register linked via surgeons' authorization identification. We included patients 18 years and older, undergoing umbilical or epigastric hernia repair between 2011 and 2020. Annual surgeon volume was categorized into ≤ 9, 10 to 19, 20 to 29, and ≥ 30 cases. Patients were followed until reoperation, death, emigration, or end of the study period.

RESULTS

We included 7,868 patients who underwent laparoscopic (n = 1,529 [19%]), open mesh (n = 4,138 [53%]), or open nonmesh (n = 2,201 [28%]) repair. There was an increased risk of reoperation after laparoscopic umbilical or epigastric hernia repair for surgeons with ≤ 9 (hazard ratio 6.57; p = 0.008), 10 to 19 (hazard ratio 6.58; p = 0.011), and 20 to 29 (hazard ratio 13.59; p = 0.001) compared with ≥ 30 cases/y. There were no differences in risk of reoperation after open mesh and open nonmesh repair in relation to annual surgeon volume.

CONCLUSIONS

There was a significantly higher risk of reoperation after laparoscopic primary ventral hernia repair performed by lower-volume surgeons compared with high-volume surgeons. Additional research investigating how sufficient surgical training and supervision are ensured is indicated to reduce risk of reoperation after primary ventral hernia repair.

Open versus laparoscopic umbilical and epigastric hernia repair: nationwide data on short- and long-term outcomes

BACKGROUND

It is unclear whether an open or laparoscopic approach results in the best outcomes for repair of umbilical and epigastric hernias. The aim of the study was to evaluate the rates of 90-day readmission and reoperation for complication, together with rate of operation for recurrence after either open or laparoscopic mesh repair for primary umbilical or epigastric hernias with defect widths above 1 cm.

METHODS

A merge of data between the Danish Hernia Database and the National Patient Registry provided data from 2007 to 2018 on perioperative information, 90-day readmission, 90-day reoperation for complication, and long-term operation for hernia recurrence.

RESULTS

A total of 6855 patients were included, of whom 4106 (59.9%) and 2749 (40.1%) patients had an open or laparoscopic repair, respectively. There were significantly more patients readmitted with a superficial surgical site infection 2.5% (102/4106) after open repair compared with laparoscopic repair (0.5% (15/2749), P < 0.001. The 90-day reoperation rate for complications was significantly higher for open repairs 5.0% (205/4106) compared with laparoscopic repairs 2.7% (75/2749), P < 0.001. The incidence of a reoperation for a severe condition was significantly increased after laparoscopic repair 1.5% (41/2749) compared with open repair 0.8% (34/4106), P = 0.010. The 4-year cumulative incidence of operation for hernia recurrence was 3.5% after open and 4.2% after laparoscopic repairs, P = 0.302.

CONCLUSIONS

Recurrence rates were comparable between open and laparoscopic repair of umbilical and epigastric hernias. Open repair was associated with a significantly higher rate of readmission and reoperation due to surgical site infection, whereas the rate of reoperation due to a severe complication was significantly higher after laparoscopic repair.

Open versus laparoscopic incisional hernia repair: nationwide database study

Background

Although laparoscopic repair of incisional hernias decreases the incidence of wound complications compared with open repair, there has been rising concern related to intraperitoneal mesh placement. The aim of this study was to examine outcomes after open or laparoscopic elective incisional hernia mesh repair on a nationwide basis.

Methods

This study analysed merged data from the Danish Hernia Database and the National Patient Registry on perioperative information, 90-day readmission, 90-day reoperation for complication, and long-term operation for hernia recurrence among patients who underwent primary repair of an incisional hernia between 2007 and 2018.

Results

A total of 3090 (57.5 per cent) and 2288 (42.5 per cent) patients had surgery by a laparoscopic and open approach respectively. The defect was closed in 865 of 3090 laparoscopic procedures (28.0 per cent). The median follow-up time was 4.0 (i.q.r. 1.8–6.8) years. Rates of readmission (502 of 3090 (16.2 per cent) versus 442 of 2288 (19.3 per cent); P = 0.003) and reoperation for complication (216 of 3090 (7.0 per cent) versus 288 of 2288 (12.5 per cent); P < 0.001) were significantly lower for laparoscopic than open repairs. Reoperation for bowel obstruction or bowel resection was twice as common after laparoscopic repair compared with open repair (20 of 3090 (0.6 per cent) versus 6 of 2288 (0.3 per cent); P = 0.044). Patients were significantly less likely to undergo repair of recurrence following laparoscopic compared with open repair of defect widths 2–6 cm (P = 0.002).

Conclusion

Laparoscopic intraperitoneal mesh repair for incisional hernia should still be considered for fascial defects between 2 and 6 cm, because of decreased rates of early complications and repair of hernia recurrence compared with open repair.

Abdominal wound dehiscence is dangerous: a nationwide study of 14,169 patients undergoing elective open resection for colonic cancer

PURPOSE

The potential impact of abdominal wound dehiscence on long-term survival after elective abdominal surgery is largely unknown. The aim of this study was to examine the impact of abdominal wound dehiscence on survival and incisional hernia repair after elective, open colonic cancer resection.

METHODS

This was a nationwide cohort study based on merged data from Danish national registries, comprising patients subjected to elective, open resection for colonic cancer between May 1, 2001 and January 1, 2016. Multivariable Cox Regression analysis and propensity score matching was applied to adjust for confounding. The associations of abdominal wound dehiscence with 90-day mortality and subsequent incisional hernia repair were also examined.

RESULTS

A total of 14,169 patients were included in the cohort, of which 549 (3.9%) developed abdominal wound dehiscence. The 5-year survival was significantly decreased in patients with abdominal wound dehiscence (42.4%, 95% CI 38.1-46.7 vs. 53.4%, 52.6-54.3, P < 0.001), which was confirmed in the multivariable analysis (HR 1.22, CI 1.06-1.39, P = 0.004). Abdominal wound dehiscence was significantly associated with increased risk of 90-day mortality (OR 1.60, CI 1.12-2.27, P = 0.009) as well as subsequent incisional hernia repair (HR 1.80, CI 1.07-3.01, P = 0.026).

CONCLUSIONS

Abdominal wound dehiscence was significantly associated with decreased survival. Fascial closure after open colonic cancer resection should be given high priority to improve the long-term survival.

Surgical repair of parastomal bulging: a retrospective register-based study on prospectively collected data

AIM

The aim of this work was to examine (1) the incidence of primary repair, (2) the incidence of recurrent repair and (3) the types of repair performed in patients with parastomal bulging.

METHOD

Prospectively collected data on parastomal bulging from the Danish Stoma Database were linked to surgical data on repair of parastomal bulging from the Danish National Patient Register. Survival statistics provided cumulative incidences and time until primary and recurrent repair.

RESULTS

In the study sample of 1016 patients with a permanent stoma and a parastomal bulge, 180 (18%) underwent surgical repair. The cumulative incidence of a primary repair was 9% [95% CI (8%; 11%)] within 1 year and 19% [95% CI (17%; 22%)] within 5 years after the occurrence of a parastomal bulge. We found a similar probability of undergoing primary repair in patients with ileostomy and colostomy. For recurrent repair, the 5-year cumulative incidence was 5% [95% CI (3%; 7%)]. In patients undergoing repair, the probability was 33% [95% CI (21%; 46%)] of having a recurrence requiring repair within 5 years. The main primary repair was open or laparoscopic repair with mesh (43%) followed by stoma revision (39%). Stoma revision and repair with mesh could precede or follow one another as primary and recurrent repair. Stoma reversal was performed in 17% of patients.

CONCLUSION

Five years after the occurrence of a parastomal bulge the estimated probability of undergoing a repair was 19%. Having undergone a primary repair, the probability of recurrent repair was high. Stoma reversal was more common than expected.

Increased risk of postoperative complications with retromuscular mesh placement in emergency incisional hernia repair: A nationwide register-based cohort study

INTRODUCTION

Incisional hernia is common after abdominal surgery. Watchful waiting carries the risk of incarceration and a need for emergency intervention. The aim of this study was to examine the risk of postoperative complications after emergency versus elective incisional hernia repair.

METHODS

Patients above 18 years of age undergoing open incisional hernia repair in Denmark in 2017-2018 were identified in the Danish Ventral Hernia Database. Patients were grouped according to elective or emergency hernia repair. The primary outcome was postoperative complications requiring operative intervention within 90 days, and the secondary outcome was postoperative length of stay.

RESULTS

We included 1050 patients, of whom 882 were admitted for elective and 168 for emergency operation. Patients undergoing emergency repair were older (64.7 years vs 59.2 years, p < 0.001), more often smokers (25.8% vs 13.6%, p = 0.003), and more often had a Charlson comorbidity score ⩾2 (26.8% vs 19.2%, p = 0.005) compared to patients undergoing elective repair. In a multivariate regression analysis, emergency compared to elective operation (OR = 2.71, 95% CI = 1.4-5.25, p = 0.003) and retromuscular compared to onlay mesh placement (OR = 2.14, 95% CI = 1.08-4.24, p = 0.013) were factors significantly associated with increased risk of postoperative complications. In a subgroup analysis including only emergency repairs, risk of complications after retromuscular mesh placement was even higher (OR = 10.12, 95% CI = 1.81-56.68, p = 0.008).

CONCLUSION

Emergency incisional hernia repair was associated with increased risk of postoperative complications and this risk was accentuated with retromuscular mesh placement. The use of retromuscular mesh in the emergency setting should be avoided, and the abdominal wall could either be closed by sutures or additional onlay mesh.

Should simultaneous stoma closure and incisional hernia repair be avoided?

PURPOSE

Patients scheduled for stoma closure may also have an incisional hernia. Studies have reported acceptable outcomes after contaminated ventral hernia repair, but whether stoma closure and incisional hernia repair should be performed as a combined procedure is unknown. This study examined combined stoma closure and incisional hernia repair compared with incisional hernia repair only.

METHODS

This was a nationwide propensity-score matched study. Patients who underwent elective incisional hernia repair from 2007-2017 were identified in the Danish Hernia Database. All patients who underwent concurrent stoma closure were matched 1:3 with patients who underwent incisional hernia repair only. The primary outcome was reoperation for hernia recurrence, whereas secondary outcomes included anastomotic leakage, length of hospital stay, and 30-day reoperation and readmission rates.

RESULTS

In total, 516 patients were included. The risk of reoperation for recurrence was increased after concurrent stoma closure compared with incisional hernia repair only (hazard ratio 1.69, 95% confidence interval 1.01-2.82, p = 0.044). Seven (5.4%) patients who underwent incisional hernia repair concurrent to stoma closure were reoperated for anastomotic leakage. Length of hospital stay and reoperation rates within 30 days were increased after concurrent stoma closure compared with incisional hernia repair only (median 8 versus 3 days, p < 0.001 and 29.5% versus 18.6%, p = 0.013), whereas there was no difference in 30-day readmission rates (p = 0.251).

CONCLUSIONS

Stoma closure and incisional hernia repair should be performed as a dual-stage procedure to decrease the risk of hernia recurrence.

Differential recurrence after laparoscopic incisional hernia repair: importance of a nationwide registry-based mesh surveillance

BACKGROUND

Identification of suboptimal mesh products is essential to improve the outcome after hernia surgery. This study investigated whether a national clinical database combined with administrative registries may serve as a tool for postmarketing evaluation of mesh products for hernia surgery.

METHODS

This was a propensity score-matched case-control cohort study comparing outcomes in patients undergoing laparoscopic incisional hernia repair with either one particular mesh or any other synthetic mesh. Data on patients registered in the Danish Ventral Hernia Database between 2010 and 2016 were combined with administrative data from the Danish National Patient Registry. The primary outcome was operation for recurrence. Secondary outcomes were 30-day readmission, 30-day reoperation for complications (excluding hernia recurrence), and mortality after 30 and 90 days.

RESULTS

In total, 740 patients who underwent repair with one particular mesh were matched with 1479 patients who received any other synthetic mesh. The rate of repair for hernia recurrence was significantly higher in the particular mesh group than in the reference group: 12·8 versus 6·3 per cent respectively (hazard ratio 2·09, 95 per cent c.i. 1·57 to 2·79; P < 0·001). Use of the particular mesh increased the risk of readmission (odds ratio (OR) 1·53, 1·16 to 2·01; P = 0·002) and reoperation for a complication (OR 1·60, 1·03 to 2·47, P = 0·030). No difference in mortality was found.

CONCLUSION

Clinical registries with prospectively collected data can provide long-term surveillance of commercial mesh. Laparoscopic incisional hernia repair with one particular mesh was associated with an increased rate of short-term complications and double the risk of repair for recurrence.

Incidence of Incisional Hernia Repair After Laparoscopic Compared to Open Resection of Colonic Cancer: A Nationwide Analysis of 17,717 Patients

BACKGROUND

It remains unknown whether laparoscopic compared to open surgery translates into fewer incisional hernia repairs (IHR). The objectives of the current study were to compare the long-term incidence of IHR and the size of repaired hernias between patients subjected to laparoscopic or open resection of colonic cancer.

METHODS

This was a nationwide cohort study comprised of patients undergoing resection for colonic cancer between January 2007 and March 2016 according to the Danish Colorectal Cancer Group database. Patients who subsequently underwent IHR were identified in the Danish Ventral Hernia Database, from which information about the priority of the hernia repair and the size of the fascial defect was retrieved.

RESULTS

The study included 17,717 patients, of whom 482 (2.7%) underwent subsequent IHR during a median follow-up of 4.7 (interquartile range 2.8-6.9) years. There was no significant difference in the 5-year cumulative incidence of hernia repair after laparoscopic compared to open colonic resection (3.9%, CI 3.3-4.4% vs 4.1%, CI 3.5-4.6%). After adjustment for confounders, laparoscopic approach was associated with an increased rate of emergency IHR (HR 2.37, 95% CI 1.03-5.46, P = 0.042) as opposed to elective IHR (HR 0.91, 95% CI 0.73-1.14, P = 0.442). Laparoscopic surgery was significantly associated with a decreased fascial defect area compared to open surgery (mean difference -16.0 cm², 95% CI -29.4 to -2.5, P = 0.020).

CONCLUSIONS

There was no difference in the incidence of IHR after open compared to laparoscopic resection. Compared to the open approach, laparoscopic resection increased the rate of subsequent emergency IHR, suggesting that a more aggressive therapeutic approach may be warranted in this patient group upon diagnosis of an incisional hernia.

Incisional hernia repair in women of childbearing age: A nationwide propensity-score matched study

BACKGROUND & AIMS

Although incisional hernia repair in women of childbearing age is not rare, hernia disease in this group of patients is sparsely documented. The aim of this study was to examine long-term clinical results after incisional hernia repair in women of childbearing age.

MATERIAL AND METHODS

This nationwide cohort study examined incisional hernia repair from 2007 to 2013 in women of childbearing age, registered prospectively in the Danish Ventral Hernia Database. All women with a subsequent pregnancy were included, and a 1:3 propensity-score matched group of women with an incisional hernia repair without a subsequent pregnancy. A prospective follow-up was conducted, including a validated questionnaire. The primary outcome was recurrence, and the secondary outcome was chronic pain from the operated site.

RESULTS

In total, 124 (70.5%) women responded, 47 and 77 women with and without a subsequent pregnancy, respectively. The 5-year cumulative incidence of recurrence was 41.0% (95% confidence interval 32.0%-49.9%). After adjustment for potential confounders, subsequent pregnancy was independently associated with recurrence (hazard ratio 1.83, 95% confidence interval 1.02-3.29, p = 0.044). Twenty-six (21.0%) women reported chronic pain (moderate, n = 21; severe, n = 5) with no difference between women with and without a subsequent pregnancy. Hernia recurrence, higher body mass index, and smoking were associated with chronic pain.

CONCLUSION

Pregnancy following incisional hernia repair was associated with an increased risk of recurrence, but not with chronic pain.

Pitfalls in interpretation of large registry data on hernia repair

Since more and more hernia registries are being created and the number of patients included is increasing, knowledge of potential pitfalls in interpretation of registry data has to be known and dealt with. This invited commentary is to discuss some of these topics. The aim is to present and discuss the main shortcoming of register-based studies and how to deal with these problems, to contribute to more validated results and eventually improved surgical outcomes.

Decreased re-operation rate for recurrence after defect closure in laparoscopic ventral hernia repair with a permanent tack fixated mesh: a nationwide cohort study

PURPOSE

To investigate whether defect closure in laparoscopic ventral hernia repair reduces the re-operation rate for recurrence compared with no defect closure.

METHODS

Data were extracted from the Danish Ventral Hernia Database. Adults with an elective laparoscopic ventral hernia repair with tacks used as mesh fixation were included, if their first repair was between the 1st of January 2007 and the 1st of January 2017. Patients with defect closure were compared with no defect closure. Re-operation rates are presented as crude rates and cumulated adjusted re-operation rates. Sub-analyses assessed the effect of the suture material used during defect closure and also whether defect closure affected both primary and incisional hernias equally.

RESULTS

Among patients with absorbable tacks as mesh fixation, 443 received defect closure and 532 did not. For patients with permanent tacks, 393 had defect closure and 442 did not. For patients with permanent tacks as mesh fixation, the crude re-operation rates were 3.6% with defect closure and 7.2% without defect closure (p = 0.02). The adjusted cumulated re-operation rate was significantly reduced with defect closure and permanent tacks (hazard ratio = 0.53, 95% confidence interval = 0.28-0.999, p = 0.05). The sub-analysis suggested that defect closure was only beneficial for incisional hernias, and not primary hernias. We did not find any benefits of defect closure for patients with absorbable tacks as mesh fixation.

CONCLUSION

This nationwide cohort study showed a reduced risk of re-operation for recurrence if defect closure was performed in addition to permanent tacks as mesh fixation during laparoscopic incisional hernia repair.

Influence of MMP inhibitor GM6001 loading of fibre coated polypropylene meshes on wound healing: Implications for hernia repair

Polypropylene meshes are standard for hernia repair. Matrix metalloproteinases play a central role in inflammation. To reduce the inflammatory response and improve remodelling with an associated reduction of hernia recurrence, we modified polypropylene meshes by nanofibre coating and saturation with the broad-spectrum matrix metalloproteinase inhibitor GM6001. The aim was to modulate the inflammatory reaction, increase collagen deposition and improve mesh biointegration. Polypropylene meshes were surface-modified with star-configured NCO-sP(EO -stat-PO) and covered with electrospun nanofibres (polypropylene-nano) and GM6001 (polypropylene-nano-GM). In a hernia model, defects were reconstructed with one of the meshes. Inflammation, neovascularization, bio-integration, proliferation and apoptosis were assessed histologically, collagen content and gelatinases biochemically. Mesh surface modification resulted in higher inflammatory response compared to polypropylene. Pro-inflammatory matrix metalloproteinase-9 paralleled findings while GM6001 reduced matrix metalloproteinase-9 significantly. Significantly increased matrix metalloproteinase-2 beneficial for remodelling was noted with polypropylene-nano-meshes. Increased vascular endothelial growth factor, neo-vascularization and collagen content were measured in polypropylene-nano-meshes compared to polypropylene. GM6001 significantly reduced myofibroblasts. This effect ended after d14 due to engineering limitations with release of maximal GM6001 loading. Nanofibre-coating of polypropylene-meshes confers better tissue vascularization to the cost of increased inflammation. This phenomenon can be only partially compensated by GM6001. Future research will enable higher GM6001 uptake in nano-coated meshes and may alter mesh biointegration in a more pronounced way.

A systematic methodological review of reported perioperative variables, postoperative outcomes and hernia recurrence from randomised controlled trials of elective ventral hernia repair: clear definitions and standardised datasets are needed

BACKGROUND

This systematic review assesses the perioperative variables and post-operative outcomes reported by randomised controlled trials (RCTs) of VH repair. This review focuses particularly on definitions of hernia recurrence and techniques used for detection.

OBJECTIVE

Our aim is to identify and quantify the inconsistencies in perioperative variable and postoperative outcome reporting, so as to justify future development of clear definitions of hernia recurrence and a standardised dataset of such variables.

METHODS

The PubMed database was searched for elective VH repair RCTs reported January 1995 to March 2016 inclusive. Three independent reviewers performed article screening, and two reviewers independently extracted data. Hernia recurrence, recurrence rate, timing and definitions of recurrence, and techniques used to detect recurrence were extracted. We also assessed reported post-operative complications, standardised operative outcomes, patient reported outcomes, pre-operative CT scan hernia dimensions, intra-operative variables, patient co-morbidity, and hernia morphology.

RESULTS

31 RCTs (3367 patients) were identified. Only 6 (19.3%) defined hernia recurrence and methods to detect recurrence were inconsistent. Sixty-four different clinical outcomes were reported across the RCTs, with wound infection (30 trials, 96.7%), hernia recurrence (30, 96.7%), seroma (29, 93.5%), length of hospital stay (22, 71%) and haematoma (21, 67.7%) reported most frequently. Fourteen (45%), 11 (35%) and 0 trials reported CT measurements of hernia defect area, width and loss of domain, respectively. No trial graded hernias using generally accepted scales.

CONCLUSION

VH RCTs report peri- and post-operative variables inconsistently, and with poor definitions. A standardised minimum dataset, including definitions of recurrence, is required.

Systematic review and network meta-analysis of methods of mesh fixation during laparoscopic ventral hernia repair

BACKGROUND

Ventral hernia repairs are common and have high recurrence rates. They are usually repaired laparoscopically with an intraperitoneal mesh, which can be fixed in various ways. The aim was to evaluate the recurrence rates for the different fixation techniques.

METHODS

This systematic review included studies with human adults with a ventral hernia repaired with an intraperitoneal onlay mesh. The outcome was recurrence at least 6 months after operation. Cohort studies with 50 or more participants and all RCTs were included. PubMed, Embase and the Cochrane Library were searched on 22 September 2016. RCTs were assessed with the Cochrane risk-of-bias assessment tool and cohort studies with the Newcastle-Ottawa scale. Studies comparing fixation techniques were included in a network meta-analysis, which allowed comparison of more than two fixation techniques.

RESULTS

Fifty-one studies with a total of 6553 participants were included. The overall crude recurrence rates with the various fixation techniques were: absorbable tacks, 17·5 per cent (2 treatment groups); absorbable tacks with sutures, 0·7 per cent (3); permanent tacks, 7·7 per cent (20); permanent tacks with sutures, 6·0 per cent (25); and sutures, 1·5 per cent (6). Six studies were included in a network meta-analysis, which favoured fixation with sutures. Although statistical significance was not achieved, there was a 93 per cent chance of sutures being better than one of the other methods.

CONCLUSION

Both crude recurrence rates and the network meta-analysis favoured fixation with sutures during laparoscopic ventral hernia repair.