Postoperative Incision Hernia in Patients with Abdominal Aortic Aneurysm and Aortoiliac Occlusive Disease: A Systematic Review

Prophylactic mesh reinforcement versus primary suture for abdominal wall closure after elective abdominal aortic aneurysm repair with midline laparotomy incision: Updated systematic review including time-to-event meta-analysis and trial sequential analysis of randomised controlled trials

OBJECTIVE

Patients undergoing open abdominal aortic aneurysm (AAA) repair have a high risk of incisional hernia. Heterogeneity in recommendations regarding prophylactic mesh reinforcement between scientific society guidelines reflects the lack of sufficient data, with the Society for Vascular Surgery making no recommendation on methods for abdominal wall closure. We aimed to synthesise the most current evidence on mesh versus primary suture abdominal wall closure after open AAA repair.

METHODS

A systematic review was conducted of randomised controlled trials (RCTs) comparing mesh reinforcement with primary abdominal wall closure for patients who underwent elective AAA repair with a midline laparotomy incision. Dichotomous and time-to-event data were pooled using random effects models, applying the Mantel-Haenszel or inverse variance statistical method. The revised Cochrane tool and GRADE framework were used to assess the risk of bias and certainty of evidence, respectively. Trial sequential analysis assumed alpha = 5% and power = 80%.

RESULTS

Five RCTs were included reporting a total of 487 patients (260 in the mesh group and 227 in the primary suture group). Patients who had mesh closure had statistically significantly lower odds of developing incisional hernia after open AAA repair than those with primary suture closure (odds ratio (OR) 0.20, 95% confidence interval (CI) 0.09 - 0.43). Time-to-event analysis confirmed the hazard of incisional hernia was statistically significantly lower in patients who had mesh closure (p<0.05). Meta-analysis found statistically significantly lower odds of reoperation for incisional hernia in the mesh group (OR 0.23, 95% CI 0.06 - 0.93), but there was no statistically significant difference in wound infection (risk difference 0.02, 95% CI -0.03 - 0.08). The overall risk of bias was low in one study, high in two studies, and "some concerns" in two studies for incisional hernia and reoperation for incisional hernia, and high in all studies reporting wound infection. The certainty of evidence was judged to be low for all outcomes. Trial sequential analysis confirmed a benefit of mesh reinforcement in reducing the risk of incisional hernia.

CONCLUSION

Meta-analysis of the highest-level data demonstrated a benefit of prophylactic mesh reinforcement, with trial sequential analysis confirming no additional RCTs required. This provides compelling evidence to support the use of mesh for midline laparotomy closure in patients undergoing open AAA repair.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Wound healing and hernia after abdominal aortic aneurysm repair: Onlay self-gripping polyester mesh reinforcement compared with small bite sutured closure

BACKGROUND

Prophylactic mesh implantation following open surgical repair of abdominal aortic aneurysm is a debatable subject.

OBJECTIVE

To assess the efficacy of a self-gripping polyester mesh used in on-lay technique to prevent incisional hernia after open abdominal aortic aneurysm repair.

METHODS

We retrospectively reviewed the records of 495 patients who underwent aortic surgery between May 2017 and May 2021. Patients included in the study underwent open surgical repair for infrarenal abdominal aortic aneurysm (AAA) with closure of the abdominal wall with either small bite suture technique or prophylactic mesh reinforcement. Primary endpoint of the study was the occurrence of incisional hernia during a two-year follow-up period. Secondary endpoints were mesh-related complications.

RESULTS

Mesh implantation with the on-lay technique was successful in all cases. No patient in the mesh group developed an incisional hernia during the 24-month follow-up period. Two patients in the non-mesh group developed a symptomatic incisional hernia during the follow-up period at 6 months. Three cases of post-operative access site complications were observed in the mesh group.

CONCLUSIONS

Application of a self-gripping polyester mesh using the on-lay technique demonstrates acceptable early-durability after open surgical repair of abdominal aortic aneurysms. However, it appears to be associated with a number of post-operative access site complications.

Incisional Hernias after Vascular Surgery for Aortoiliac Aneurysm and Aortoiliac Occlusive Arterial Disease: Has Prophylactic Mesh Changed This Scenario?

BACKGROUND

 Incisional hernia (IH) is an important surgical complication that has several ways of prevention, including modifications in the surgical technique of the initial procedure. Its incidence can reach 69% in high-risk patients and long-term follow-up. Of the risky procedures, open abdominal aortic aneurysmectomy is the one with the highest risk. Ways to reduce this morbid complication were suggested, and prophylactic mesh rises as an important tool to prevent recurrence.

METHODS

 A retrospective cohort study review of medical records of patients undergoing vascular surgery for abdominal aortoiliac aneurysm (AAA) or vascular bypass surgery due to aortoiliac occlusive disease. We identified 193 patients treated between 2010 and 2020. We further performed a one-to-nine matching analysis between the use of prophylactic mesh and control groups, based on estimated propensity scores for each patient.

RESULTS

 Prophylactic mesh group had a 18% lower risk of IH, compared with the control group (relative risk: 0.82; 95% confidence interval [CI] = 0.74-0.93). The difference in IH rates between the groups compared was 2.6% (95% CI: -19.8 to 25.5). From the perspective of the number needed to treat, it would be necessary to use prophylactic mesh in 39 (95% CI: 35-44) patients to avoid one IH in this population.

CONCLUSION

 Use of prophylactic mesh in the repair of AAA significantly reduces the incidence of IH in nearly one in five cases. Our data suggest that there is benefit in the use of prophylactic mesh in open aneurysmectomy surgery regarding postoperative IH development.

Assessment of Quality of Life after Endovascular and Open Abdominal Aortic Aneurysm Repair: A Retrospective Single-Center Study

Postoperative quality of life is an important outcome parameter after treatment of abdominal aortic aneurysms. The aim of this retrospective single-center study was to assess and compare the health-related quality of life (HRQoL) of patients after open repair (OR) or endovascular treatment (EVAR), and furthermore to investigate the effect of incisional hernia (IH) formation on HRQoL. Patients who underwent OR or EVAR for treatment of an abdominal aortic aneurysm between 2008 and 2016 at a University Medical Center were included. HRQoL was assessed using the SF-36 questionnaire. The incidence of IH was recorded from patient files and by telephone contact. SF-36 scores of 83 patients (OR: n = 36; EVAR: n = 47) were obtained. The mean follow-up period was 7.1 years. When comparing HRQoL between OR and EVAR, patients in both groups scored higher in one of the eight categories of the SF36 questionnaires. The incidence of IH after OR was 30.6%. In patients with postoperative IH, HRQoL was significantly reduced in the dimensions “physical functioning”, “role physical” and “role emotional” of the SF-36. Based on this data, it can be concluded that neither OR nor EVAR supply a significant advantage regarding HRQoL. In contrast, the occurrence of IH has a relevant impact on the HRQoL of patients after OR.

Early and late results of open surgical and endovascular treatment of infrarenal abdominal aortic aneurysms, selected according to surgical risk

Background

Open surgical repair (OSR) and endovascular aneurysm repair (EVAR) surgery are alternative treatments for infrarenal abdominal aortic aneurysm (IRAAA).

Objectives

To compare OSR and EVAR for the treatment of IRAAA.

Methods

119 patients with IRAAA were electively operated by the same surgeon between January 1, 2006 and December 31, 2015, following selection for OSR or EVAR according to surgical risk. Complications, reinterventions, failures, and early and late mortality were analyzed.

Results

63 OSR and 56 EVAR patients were analyzed. They were similar in terms of age (70 years), gender (92% men), and average diameter of IRAAA (6.5 cm), but with different comorbidities, surgical risk, and anatomy. EVAR was better than OSR regarding time in the operating theatre (177.5 vs. 233.3 minutes), need for transfusion (25 vs. 73%), and length of stay in ICU (1.3 vs. 3.3 days) and hospital (8.1 vs. 11.1 days). OSR allowed more associated procedures to be conducted simultaneously (19.0 vs. 1.8%). There were no significant differences between the groups with respect to complications (25.4 vs. 25.1%), reinterventions (3.2 vs. 5.2%), or early mortality (1.6 vs. 0%). During follow-up, OSR was associated with fewer revisions (3.13 vs. 4.21), angio-CTs (0.22 vs. 3.23), complications (6.4 vs. 37.5%), reinterventions (3.2 vs. 23.2%), and failures (1.6 vs. 10.7%), and had better survival (78.2 vs. 63.2%).

Conclusions

Correct selection of patients achieves excellent results because it avoids OSR in patients at high risk and avoids EVAR in patients with high anatomical complexity, achieving similar results in the perioperative period, but better results for OSR over the course of follow-up.

Abdominal incision defect following AAA-surgery (AIDA): 2-year results of prophylactic onlay-mesh augmentation in a multicentre, double-blind, randomised controlled trial

The reported incidence of incisional hernia following repair of abdominal aortic aneurysm (AAA) via midline laparotomy is up to 69%. This prospective, multicenter, double-blind, randomised controlled trial was conducted at eleven hospitals in Germany. Patients aged 18 years or older undergoing elective AAA-repair via midline incision were randomly assigned using a computer-generated randomisation sequence to one of three groups for fascial closure: with long-term absorbable suture (MonoPlus^®, group I), long-term absorbable suture and onlay mesh reinforcement (group II) or extra long-term absorbable suture (MonoMax^®, group III). The primary endpoint was the incidence of incisional hernia within 24 months of follow-up, analysed by intention to treat. Physicians conducting the postoperative visits and the patients were blinded. Between February 2011 and July 2013, 104 patients (69.8 ± 7.7 years) were randomised, 99 of them received a study intervention. The rate of incisional hernia within 24 months was not significantly reduced with onlay mesh augmentation compared to primary suture (p = 0.290). Furthermore, the rate of incisional hernia did not differ significantly between fascial closure with slow and extra long-term absorbable suture (p = 0.111). Serious adverse events related to study intervention occurred in five patients (5.1%) from treatment groups II and III. Wound healing disorders were more frequently seen after onlay mesh implantation on the day of discharge (p = 0.010) and three (p = 0.009) and six (p = 0.023) months postoperatively. The existing evidence on prophylactic mesh augmentation in patients undergoing AAA-repair via midline laparotomy probably needs critical review. As the implementation of new RCTs is considered difficult due to the increasing number of endovascular AAA treated, registry studies could help to collect and evaluate data in cases of open AAA-repair. Comparisons between prophylactic mesh implantation and the small bite technique are also required. Trial registration: ClinicalTrials.gov Identifier: NCT01353443. Funding Sources: Aesculap AG, Tuttlingen, Germany.

Do Hernias Contribute to Increased Severity of Aneurysmal Disease among Abdominal Aortic Aneurysm Patients?

Background  Connective tissue disorders could contribute to the pathogenesis of both abdominal aortic aneurysms (AAA) and hernias. We tested the hypothesis that hernias in AAA patients contribute to increased severity of the aneurysmal disease.

Methods  A questionnaire was used to collect information from 195 AAA patients divided into four groups: (1) survivors ( n  = 22) of ruptured AAA, (2) patients ( n  = 90) after elective open repair, (3) patients ( n  = 43) after elective endovascular repair (EVAR), and (4) patients ( n  = 40) under surveillance of AAA. The control group consisted of 100 patients without AAA whose abdominal computed tomography (CT) scans were examined for the presence of hernias. Mann–Whitney U -test, Chi-squared ( χ² ) test, or Fisher's exact test (as appropriate) were used for statistical analyses. Multivariate logistic regression was used to control for potential confounding variables such as sex and age.

Results  The prevalence of inguinal hernias was significantly higher in the AAA than the control group (25 vs. 9%, p  = 0.001) and did not differ between the AAA subgroups (9, 24, 35, and 23% in subgroups 1 through 4, respectively, p  = 0.15) based on univariate analysis. The prevalence of inguinal hernias did not differ ( p  = 0.15) between the two open surgery groups (groups 1 and 2), or when comparing all three operative procedures as a combined group to group 4 ( p  = 0.73). The prevalences of incisional hernias were 18 and 24% for groups 1 and 2, respectively, with no significant difference ( p  = 0.39). Inguinal hernia demonstrated a significant association with AAA on multivariate analysis ( p  = 0.006; odds ratio [OR] = 4.00; 95% confidence interval [CI] = 1.49–10.66).

Conclusions  Our study confirms previous observations that patients with AAA have a high prevalence of hernias. Our results suggest that hernias do not contribute to increased severity of the aneurysmal disease.

Association of Abdominal Aortic Aneurysm and Simple Renal Cysts: A Systematic Review and Meta-Analysis

BACKGROUND-OBJECTIVE

Prior studies have suggested a higher prevalence of simple renal cysts (SRC) among patients with aortic disease, including abdominal aortic aneurysms (AAA). Thus, the aim of this study was to systematically review all currently available literature and investigate whether patients with AAA are more likely to have SRC.

METHODS

This study was performed according to the PRISMA guidelines. A meta-analysis was conducted with the use of random effects modeling and the I-square was used to assess heterogeneity. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were synthesized to compare the prevalence of several patients' characteristics between AAA vs. no-AAA cases.

RESULTS

Eleven retrospective studies, 9 comparative (AAA vs. no-AAA groups) and 3 single-arm (AAA group), were included in this meta-analysis, enrolling patients (AAA: N = 2,297 vs. no-AAA: N = 35,873) who underwent computed tomography angiography as part of screening or preoperative evaluation for reasons other than AAA. The cumulative incidence of SRC among patients with AAA and no-AAA was 55% (95% CI: 49%-61%) and 32% (95% CI: 22%-42%) respectively, with a statistically higher odds of SRC among patients with AAA (OR: 3.02; 95% CI: 2.01-4.56; P< 0.001). The difference in SRC prevalence remained statistically significant in a sensitivity analysis, after excluding the study with the largest sample size (OR: 2.71; 95% CI: 1.91-3.84; P< 0.001).

CONCLUSIONS

Our meta-analysis demonstrated a 3-fold increased prevalence of SRC in patients with AAA compared to no-AAA cases, indicating that the pathogenic processes underlying SRC and AAA could share a common pathophysiologic mechanism. Thus, patients with SRC could be considered at high risk for AAA formation, potentially warranting an earlier AAA screening.

[Robotic-assisted operations for pathology of the aortoiliac segment: own experience]

AIM

The present study was aimed at assessing the results of a total of 40 vascular operations carried out using the robotic-assisted da Vinci surgical system.

PATIENTS AND METHODS

Between January 2013 and September 2019, a total of 40 robotic-assisted vascular operations were performed at the Department of Vascular Pathology and Hybrid Technologies of the Centre of Vascular and Hybrid Surgery. Of these, 31 interventions were carried out for occlusion of the aortoiliac segment and 9 for removal of an aneurysm of the infrarenal portion of the abdominal aorta. The patients were arbitrarily divided into 2 groups: the first group included those subjected to aortofemoral bypass grafting procedures for atherosclerotic steno-occlusive lesions of the aorta and iliac arteries, whereas the second group comprised the patients who underwent aneurysmoectomies with linear prosthetic repair of the abdominal aorta.

RESULTS

Altogether, elective robotic-assisted operations were successfully performed in 38 (95%) cases. Conversion to a laparotomic approach was required in 2 (5%) patients. The mean time of creating an anastomosis with the abdominal aorta amounted to 51 minutes (range 30-90), being 42±4.75 min for aortofemoral bypass grafting and 83±5.00 min for aneurysmoectomies with linear prosthetic repair of the abdominal artery. The average blood loss was 316 (range 50-1000) ml, amounting to 280±209 ml and 438±322 ml for group I and group II, respectively. With the exception of one case, all patients spent 24 hours in the intensive care unit to be then transferred to the specialized ward. The average length of hospital stay amounted to 9.8 days. One patient experienced haemorrhage from the central anastomosis in the early postoperative period and was emergently operated on from a laparotomic approach. Four (10%) patients developed nonlethal complications which were treated conservatively. During the 30-day follow-up period, no lethal outcomes, thromboses, nor infections of the prostheses were observed.

CONCLUSION

From a practical point of view, the major advantages of using the robotic-assisted complex include minimal surgical trauma, reduced blood loss, a wide range of high-precision movements of the manipulators, 3-D visualization with a 5-fold magnification, thus making it possible to create a vascular anastomosis sufficiently fast in very tight spaces in the body. Our experience with laparoscopic robotic-assisted surgery demonstrated feasibility of using this technique for treatment of pathology of the aortoiliac segment.

Transabdominal approach associated with increased long-term laparotomy complications after open abdominal aortic aneurysm repair

OBJECTIVE

Although the transabdominal approach (TAA) and lateral approach (LA) to open abdominal aortic aneurysm repair (OAR) are both acceptable and widely used, a paucity of data evaluating subsequent postoperative laparotomy-associated complications (LCs) is available. The aim of the present study was to establish the incidence of LCs after OAR and determine which approach was associated with an increase in long-term LCs.

METHODS

An institutional database for OAR (2010-2019) was queried, excluding urgent and emergent cases. The primary endpoint was long-term LCs, defined as any complication related to entry into the abdomen. The LA included retroperitoneal and thoracoabdominal approaches and the TAA included all patients with midline incisions. A Kaplan-Meier analysis was used to estimate the freedom from LCs, and the Fine-Gray method was used to determine the predictors of LCs, with death as a competing risk.

RESULTS

A total of 241 patients (mean age, 70.0 ± 9.1 years; 71.7% men) had undergone OAR, 91 via a TAA and 150 via a LA. The patients in the TAA group were significantly younger (age, 66.7 ± 8.9 vs 72.1 ± 8.7 years; P < .001), more likely to be male (83.5% vs 64.7%; P = .002), and more likely to have a history of small bowel obstruction (SBO; 3.3% vs 0%; P = .025). Patients in the LA group were more likely to have required a supraceliac clamp (20.7% vs 1.1%; P < .001). No difference was found in the incidence of perioperative complications or long-term mortality. The most common LCs were hernia (TAA, 26.4%; LA, 11.3%; P = .003), SBO (TAA, 8.8%, LA, 1.3%; P = .005), and other (TAA, 13.2%; LA, 2.0%; P = .001), which included evisceration, bowel ischemia, splenic injuries requiring reintervention, enterocutaneous fistula, internal hernia, and retrograde ejaculation. Operative LCs were more common in the TAA group (17.6% vs 2.7%; P < .001). The unadjusted 1-, 3-, and 5-year freedom from LCs was 77.7% (95% confidence interval [CI], 66.0%-85.8%), 60.5% (95% CI, 46.5%-71.9%), and 54.0% (95% CI, 38.8%-67.0%) for TAA and 94.8% (95% CI, 88.8%-97.7%), 82.2% (95% CI, 72.2%-88.9%), and 79.1% (95% CI, 68.4%-86.5%) for LA, respectively (log-rank P < .001). The predictors for LCs were a history of SBO (P = .001), increasing body mass index (P = .005), and the use of the TAA (P < .001).

CONCLUSIONS

Use of the TAA was an independent predictor of long-term LCs after OAR, along with an increasing body mass index and a history of SBO. In patients with amenable anatomy, the LA is favorable for preventing long-term LCs, especially in high-risk patients.

Selected conditions associated with an increased incidence of incisional hernia: A review of molecular biology

BACKGROUND

Incisional hernias (IH) following a laparotomy, on average, occur in 10-20% of patients, however, little is known about its molecular basis. Thus, a better understanding of the molecular mechanisms could lead to the identification of key target(s) to intervene pre-and post-operatively.

METHODS

We examined the current literature describing the molecular mechanisms of IH and overlap these factors with smoking, abdominal aortic aneurysm, obesity, diabetes mellitus, and diverticulitis.

RESULTS

The expression levels of collagen I and III, matrix metalloproteinases, and tissue inhibitors of metalloproteases are abnormal in the extracellular matrix (ECM) of IH patients and ECM disorganization has an overlap with these comorbid conditions.

CONCLUSION

Understanding the pathophysiology of IH development and associated risk factors will allow physicians to identify patients that may be at increased risk for IH and to possibly act preemptively to decrease the incidence of IH.

Long-term Efficacy of EVAR in Patients Aged Less Than 65 Years with an Infrarenal Abdominal Aortic Aneurysm and Favorable Anatomy

BACKGROUND

The aim of this study was to compare early and long-term outcomes of endovascular aneurysm repair (EVAR) versus open surgical repair (OSR) in patients aged ≤ 65 years.

METHODS

Data of patients aged ≤65 years undergoing infrarenal abdominal aortic aneurysm repair, between 2005 and 2013, were retrospectively reviewed. All EVAR procedures were performed according to the instruction for use, and only OSR procedures with an infrarenal aortic cross-clamping were included in the study.

RESULTS

In this group of 115 patients (EVAR: 58 patients, 51% and OSR: 57 patients, 49%), EVAR and OSR patients had similar comorbidities, except for obesity (EVAR: 38% vs. OSR: 19%; P = 0.03). A stay in the intensive care unit (ICU) was necessary in 19% of patients with EVAR versus 79% with OSR (P = 0.001), and the amount of blood transfusion was 236 ± 31 mL for EVAR versus 744 ± 98 mL for OSR (P = 0.001). The hospital stay was 4 ± 2 days for EVAR versus 9 ± 6 days for OSR (P = 0.03). The overall 30-day mortality was 1% (EVAR: 0% vs. OSR: 2%; P = 0.30). Five patients (4%) required reinterventions within 30 days (EVAR: 0% vs. OSR: 8%, P = 0.001). The mean follow-up was 86 ± 38 months. Freedom from reintervention at 10 years after EVAR was 81% versus OSR 74%; (P = 0.77). Late reinterventions were reported in 13 patients (23%) with OSR and in 10 patients (17%) with EVAR. Postoperative retrograde ejaculation occurred more often in patients with OSR (31%) versus EVAR (2%) (P = 0.001). During the follow-up, cancer was found in 19 (17%) patients with no difference between EVAR and OSR (P = 0.83). The global survival at 10 years was 72% (EVAR: 79% vs. OSR: 70%; P = 0.94).

CONCLUSIONS

In this study, EVAR was associated with a shorter hospital stay, less need for the ICU, and less early reinterventions than OSR. Survival and reinterventions during the follow-up were not significantly different between EVAR and OSR. According to these results, EVAR may be considered for patients aged ≤65 years with a favorable anatomy.

Incisional Hernia Following Open Abdominal Aortic Aneurysm Repair: A Contemporary Review of Risk Factors and Prevention

While the endovascular approach has been the treatment of choice for abdominal aortic aneurysm (AAA) repair in the modern era, open AAA repair remains a treatment option and may have a resurgence after the recent release of draft guidelines from the National Institute for Health and Care Excellence (NICE). Incisional hernia is a common long-term complication of open AAA repair and causes significant patient morbidity. As the number of patients undergoing open AAA repair increases, it is imperative that vascular surgeons are aware of and aim to reduce the complications associated with open surgery. This article summarises current evidence, highlighting the risk factors for incisional hernia and the modern surgical techniques that can prevent complications.

Abdominal Closure and the Risk of Incisional Hernia in Aneurysm Surgery - A Systematic Review and Meta-analysis

OBJECTIVES

Patients with abdominal aortic aneurysms (AAAs) have a high prevalence of incisional hernia following open repair. The choice of incision and closure technique has a significant impact on this post-operative complication. Multiple techniques exist, as well as various comparative analyses, but clinical consensus is lacking. The objective was to perform a systematic review and meta-analysis of AAA laparotomy and closure technique and the risk of incisional hernia development.

METHODS

The systematic review was performed according to the PRISMA guidelines. A literature search of all original research published until January 2019 was made. Outcome measures were surgical approach, closure technique, hernia rates, length of follow up, and method of hernia recognition. Groups were divided according to method of abdominal incision and closure technique. Differences in outcome between closure techniques were expressed as risk ratios with 95% confidence interval (CI) using a random effects model.

RESULTS

Fifteen studies were included with a cumulative cohort of between 388 and 3 399 patients compared in each group. Abdominal closure with a suture to wound length ratio of more than 4:1 compared with less than 4:1, RR 0.42 (95% CI 0.27-0.65), and abdominal closure with mesh compared with without mesh augmentation, RR 0.24 (95% CI 0.10-0.60) reduced the risk of incisional hernia. There were no significant differences in incisional hernia rate between transverse abdominal incision vs. vertical midline incision, RR 0.57 (95% CI 0.31-1.06) and between midline transperitoneal vs. all retroperitoneal incisions, RR 1.19 (95% CI 0.54-2.61).

CONCLUSION

Choice of abdominal closure technique after aneurysm surgery impacts the risk of developing incisional hernia. The use of a supportive mesh significantly reduces the risk of incisional hernia in vertical midline incisions. The same is true if a suture to wound ratio of more than 4:1 is used.

Mid-Term Outcomes of Retroperitoneal and Transperitoneal Exposures in Open Aortic Aneurysm Repair

BACKGROUND

There have been a number of studies comparing perioperative outcomes of the retroperitoneal (RP) and transperitoneal (TP) approaches to open aortic aneurysm repair (OAR), many of which have shown conflicting results. There remains a paucity of data comparing these 2 exposures beyond 30 days. The purpose of this study was to evaluate the mid-term outcomes between RP and TP exposures in OAR.

METHODS

This is a retrospective review of elective OAR from a single institution from 2010 to 2014 with at least one year of follow-up. Patients with any prior aortic repair, prior midline TP or RP exposures, prior small bowel obstruction (SBO), or prior abdominal wall hernia repair were excluded. Patients' demographics, comorbidities, intraoperative details, and postoperative variables up to 5 years were compared. Primary outcomes were all-cause mortality, aortic or arterial reinterventions, incisional reinterventions, SBO or reintervention for SBO, and composite reintervention.

RESULTS

Of the 273 OARs identified, 136 OARs (86 TP and 50 RP exposures) met criteria for the study. The average follow-up was 43.4 months. Of the preoperative and intraoperative characteristics, patients with RP exposures were significantly more likely to be female (30% vs. 12.8%; P = .014) and to have larger aneurysm (6.1 ± 1.02 cm vs. 5.4 ± 1.01 cm; P < .001), tube graft (48% vs 19.8%; P < .001), and renal bypass (30% vs. 2.3%; P < .001). Patients with TP exposures were significantly more likely to have inferior mesenteric artery reimplantation (15.1% vs. 4%; P = .046), infrarenal clamping (65.9% vs. 22%; P < .001), and iliac aneurysm (36% vs. 4%; P < .001). During mid-term follow-up, there was not a difference in all-cause survival at 3 years (95.8% vs. 95.8%; P = .52). Although there were more incisional hernias in the TP group (48% vs. 8%; P < .001), there was no difference in incisional reinterventions (14% vs. 6%; P = .36). There were no differences in aortic or arterial reinterventions (5% vs. 4%; P = .86), SBO (7% vs. 0%; P = .99), intervention for SBO (3% vs. 0%; P = .99), or composite reinterventions (16% vs. 10%; P = .6) between the TP and RP exposures.

CONCLUSIONS

In mid-term follow-up, OAR through TP exposure had more incisional hernias compared with RP exposure. However, there is no difference in mortality or composite reinterventions between approaches.

Correlation of Baseline Plasma and Inguinal Connective Tissue Metalloproteinases and Their Inhibitors With Late High-Pressure Endoleak After Endovascular Aneurysm Repair: Long-term Results

Purpose: To investigate whether plasma and connective tissue matrix metalloproteinases (MMP) and their inhibitors (TIMP) may predict late high-pressure endoleak after endovascular aneurysm repair (EVAR). Materials and Methods: Samples of inguinal fascia and blood were collected in 72 consecutive patients (mean age 73.1 years; 68 men) undergoing primary EVAR with the Endurant stent-graft. Baseline plasma levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 and baseline MMP-2 and MMP-9 activity estimated using gelatin zymography (GZ) were compared between patients who developed late endoleak in follow-up and those who did not. Subgroup analyses were performed between patients with (n=18) and without inguinal hernias and between patients with moderate-diameter (50–59 mm; n=45) or large-diameter (≥60 mm; n=27) abdominal aortic aneurysms (AAA) at primary EVAR. Results: The mean follow-up period was 63.1 months (range 7.5–91.5), during which time 13 (18.1%) patients developed type I (6 Ia and 5 Ib) or 2 type III endoleaks. Only GZ-analyzed proMMP-9 concentrations were higher in the endoleak group than in patients without endoleak (mean difference 8.44, 95% CI −19.653 to −1.087, p=0.03). The patients with primary inguinal hernia at presentation had significantly higher tissue TIMP-2 values (0.8±0.7 vs 0.5±0.4, p=0.018) but lower plasma total (pro- + active) MMP-9 values (11.9±7.8 vs 16.2±7.4, p=0.042) than patients without hernias at the time of EVAR. Patients with AAAs ≥60 mm had significantly higher mean tissue homogenate levels of total (pro- + active) MMP-9 (p=0.025) and total (pro- + active) MMP-2 (p=0.049) as well as higher proMMP-9 (p=0.018) and total (pro- + active) MMP-9 (p=0.021) levels based on GZ compared to patients with moderate-diameter AAAs. Regression analysis revealed a significant association between total (pro- + active) MMP-9 plasma samples and the presence of hernia (OR 0.899, 95% CI 0.817 to 0.989, p=0.029) and between GZ-analyzed proMMP-9 and late endoleak (OR 1.055, 95% CI 1.007 to 1.106, p=0.025). GZ-analyzed proMMP-9 and active MMP-9 were strong predictors of late endoleak in patients with hernia (p=0.012 and p=0.044, respectively) and in patients with AAAs ≥60 mm (p=0.018 and p=0.041 respectively). Conclusion: Inguinal fascial tissue proMMP-9 significantly predicted late endoleak. ProMMP-9 and active MMP-9 biomarkers are significantly associated with late endoleak in hernia patients and in patients with AAAs ≥60 mm. Considering the clinical association between hernia and AAA and the fact that the AAA wall connective tissue environment remains exposed to systemic circulation after EVAR, inguinal fascia extracellular matrix dysregulation and altered MMP activity may reflect similar changes in AAA biology, leading to complications such as endoleak.

Custom-Made Iliac Fenestrated Device

Iliac branch devices (IBDs) are undergoing rapid popularization. They allow for treatment of an iliac aneurysm while preserving blood flow to the hypogastric artery. Certain anatomic criteria are necessary for the use of an iliac side branch device to be technically feasible. Custom-made fenestrated iliac stent grafts may provide an alternative when anatomic criteria for an IBD are not met.

Saphenous vein graft aneurysm formation in a patient with idiopathic multiple aneurysms

True aneurysmal vein graft dilation is rare, and its etiology remains speculative. However, systemic dilation diathesis is regarded as a risk factor. We herein report a case of a rapidly expanding aneurysm in a great saphenous vein graft, resulting in distal malperfusion in a patient who had previously undergone open repair of multiple popliteal artery aneurysms. After an unsuccessful endovascular intervention, the dilated section was eventually replaced by a reversed segment of the contralateral great saphenous vein. Subsequent whole-exome sequencing identified no relevant mutations. This case provides further evidence that aneurysmal disease may be associated with systemic dilation diathesis.

Incidence of Ventral Hernia Repair after Open Abdominal Aortic Aneurysm and Open Aortofemoral or Aortoiliac Bypass Surgery: An Analysis of 17,594 Patients in the State of New York

The purpose of our study was to evaluate the rate of ventral hernia repair (VHR) after open abdominal aortic anneurysm in New York State compared with the rate of VHR after open abdominal aortic bypass procedures. The Statewide Planning and Research Cooperative System database was queried for all abdominal aortic aneurysm (AAA) and bypass procedures performed between 2000 and 2010. Social security death index was used to identify patients who died. The cause-specific Cox proportional hazard model was applied to compare the risk of having follow-up VHR between patients with AAA and bypass with death as a competing risk event. A multivariable model was used to explore independent relationship with the risk of having follow-up ventral hernia after adjusting for other factors. There were 9314 patients who underwent open AAA repair, 739 (7.93%) of which had subsequent VHR. Comparatively, 8280 patients underwent aortofemoral or aortoiliac bypass procedures, with 480 (5.8%) undergoing subsequent VHR. The observed one-year, five-year, and 10-year VHR rates for AAA versus bypass were 2.8 versus 1.8 per cent, 10.0 versus 8.0 per cent, 10.7 versus 9.38 per cent, respectively. After controlling for all other factors, patients undergoing AAA repair were more likely and elderly patients were less likely to undergo VHR (P < 0.0001). Patients with serious comorbid conditions such as valvular disease, diabetes mellitus, and neurologic disorders were less likely to undergo subsequent VHR controlling for other factors. VHR after AAA procedures is more common compared with bypass procedures for occlusive disease. Because this patient population has significant comorbidity, prophylactic mesh placement may play a role in preventing necessity for future procedures.

The Society for Vascular Surgery practice guidelines on follow-up after vascular surgery arterial procedures

Although follow-up after open surgical and endovascular procedures is generally regarded as an important part of the care provided by vascular surgeons, there are no detailed or comprehensive guidelines that specify the optimal approaches with regard to testing methods, indications for reintervention, and follow-up intervals. To provide guidance to the vascular surgeon, the Clinical Practice Council of the Society for Vascular Surgery appointed an expert panel and a methodologist to review the current clinical evidence and to develop recommendations for follow-up after vascular surgery procedures. For those procedures for which high-quality evidence was not available, recommendations were based on observational studies, committee consensus, and indirect evidence. Recognizing that there are numerous published reports on the role of duplex ultrasound for surveillance of infrainguinal vein bypass grafts, the Society commissioned a systematic review and meta-analysis on this topic. The panel classified the strength of each recommendation and the corresponding quality of evidence on the basis of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system: recommendations were graded either strong or weak, and the quality of evidence was graded high, moderate, or low. The resulting recommendations represent a wide variety of open surgical and endovascular procedures involving the extracranial carotid artery, thoracic and abdominal aorta, mesenteric and renal arteries, and lower extremity arterial revascularization. The panel also identified many areas in which there was a lack of high-quality evidence to support their recommendations. This suggests that there are opportunities for further clinical research on testing methods, threshold criteria, and the role of surveillance as well as on the modes of failure and indications for reintervention after vascular surgery procedures.

Prophylactic Mesh Reinforcement versus Sutured Closure to Prevent Incisional Hernias after Open Abdominal Aortic Aneurysm Repair via Midline Laparotomy: A Systematic Review and Meta-Analysis

OBJECTIVE/BACKGROUND

Incisional hernia is a frequent late complication after open abdominal aortic aneurysm (AAA) repair. We aimed to determine whether prophylactic mesh reinforcement of the abdominal wall at open AAA repair via midline laparotomy reduces the rate of incisional hernia compared to standard sutured closure.

METHODS

A systematic review and meta-analysis was carried out in accordance with the PRISMA statement (PROSPERO registration CRD42017072508). Randomised controlled trials (RCTs) comparing prophylactic mesh reinforcement with standard sutured closure were eligible for inclusion. MEDLINE, Embase, and the Cochrane Library were searched. A meta-analysis with a random effects model was carried out to estimate pooled risk ratios (RR) with 95% confidence intervals (CIs) for the incidence of, and re-operation rate for, incisional hernias. Assessments of methodological quality, quality of evidence, and strength of recommendations were done with the Cochrane Collaboration's tool for assessing risk of bias and the GRADE approach.

RESULTS

Four RCTs with a total of 388 patients were included in the meta-analysis. Pooled analysis showed that mesh reinforcement significantly reduced the risk of incisional hernia after AAA repair compared with standard sutured closure (RR 0.27, 95% CI 0.11-0.66). The pooled rate of re-operations was not different between groups (RR 0.23, 95% CI 0.11-1.05). Mesh reinforcement did not cause more intra-operative or post-operative complications than sutured closure. The risk of bias in studies was low and the quality of evidence was rated as moderate.

CONCLUSION

Prophylactic mesh reinforcement of the abdominal wall after open AAA repair via midline laparotomy significantly reduces the risk of incisional hernia. However, no significant difference in re-operation for incisional hernia was found.

Stomal Closure: Strategies to Prevent Incisional Hernia

Incisional hernias following ostomy reversal occur frequently. Incisional hernias at the site of a previous stoma closure can cause significant morbidity, impaired quality of life, lead to life-threatening hernia incarceration or strangulation and result in a significant financial burden on health care systems Despite this, the evidence base on the subject is limited. Many recognised risk factors for the development of incisional hernia following ostomy reversal are related to patient factors such as age, malignancy, diabetes, COPD, hypertension and obesity, and are not easily correctable. There is a limited amount of evidence to suggest that prophylactic mesh reinforcement may be of benefit to reduce the post stoma closure incisional hernia rate but a further large scale randomised controlled trial is due to report in the near future. There appears to be weak evidence to suggest that surgeons should favour circular, or "purse-string" closure of the skin following stoma closure in order to reduce the risk of SSI, which in turn may reduce incisional hernia formation. There remains the need for further evidence in relation to suture technique, skin closure techniques, mechanical bowel preparation and oral antibiotic prescription focusing on incisional hernia development as an outcome measure. Within this review, we discuss in detail the evidence base for the risk factors for the development of, and the strategies to prevent ostomy reversal site incisional hernias.

Collagenopathies-Implications for Abdominal Wall Reconstruction: A Systematic Review

Background:

The etiology of hernia formation is strongly debated and includes mechanical strain, prior surgical intervention, abnormal embryologic development, and increased intraabdominal pressure. Although the most common inciting cause in ventral hernias is previous abdominal surgery, many other factors contribute. We explore this etiology through an examination of the current literature and existing evidence on patients with collagen vascular diseases, such as Ehlers–Danlos syndrome.

Methods:

A systematic review of the published literature was performed of all available Spanish and English language PubMed and Cochrane articles containing the key words “collagenopathies,” “collagenopathy,” “Ehlers-Danlos,” “ventral hernia,” and “hernia.”

Results:

Three hundred fifty-two articles were identified in the preliminary search. After review, 61 articles were included in the final review.

Conclusions:

Multiple authors suggest a qualitative or quantitative defect in collagen formation as a common factor in hernia formation. High-level clinical data clearly linking collagenopathies and hernia formation are lacking. However, a trend in pathologic studies suggests a link between abnormal collagen production and/or processing that is likely associated with hernia development.

Prevention of Incisional Hernias by Prophylactic Mesh-augmented Reinforcement of Midline Laparotomies for Abdominal Aortic Aneurysm Treatment: A Randomized Controlled Trial

BACKGROUND

The incidence of incisional hernias after abdominal aortic aneurysm repair is high. Prophylactic mesh-augmented reinforcement during laparotomy closure has been proposed in patients at high risk of incisional hernia.

METHODS

A multicenter randomized trial was conducted on patients undergoing elective abdominal aortic aneurysm repair through a midline laparotomy (Clinical.Trials.gov: NCT00757133). In the study group, retromuscular mesh-augmented reinforcement was performed with a large-pore polypropylene mesh (Ultrapro, width 7.5 cm). The primary endpoint was the incidence of incisional hernias at 2-year follow-up.

RESULTS

Between February 2009 and January 2013, 120 patients were recruited at 8 Belgian centers. Patients' characteristics at baseline were similar between groups. Operative and postoperative characteristics showed no difference in morbidity or mortality. The cumulative incidence of incisional hernias at 2-year follow-up after conventional closure was 28% (95% confidence interval [CI], 17%-41%) versus 0% (95% CI, 0%-6%) after mesh-augmented reinforcement (P < 0.0001; Fisher exact test). The estimated "freedom of incisional hernia" curves (Kaplan-Meier estimate) were significantly different across study arms (χ = 19.5, P < 0.0001; Mantel-Cox test). No adverse effect related to mesh-augmented reinforcement was observed, apart from an increased mean time to close the abdominal wall for mesh-augmented reinforcement compared with the control group: 46 minutes (SD, 18.6) versus 30 minutes (SD, 18.5), respectively (P < 0.001; Mann-Whitney U test).

CONCLUSIONS

Prophylactic retromuscular mesh-augmented reinforcement of a midline laparotomy in patients with abdominal aortic aneurysm is safe and effectively prevents the development of incisional hernia during 2 years, with an additional mean operative time of 16 minutes.

Off-Label Iliac Side Branch Application for Salvage of an Accessory Renal Artery

Purpose: To present the off-label use of an iliac side branch device to connect an accessory right renal artery to a bifurcated endograft in infrarenal aortic aneurysm repair. Case Report: An 83-year-old woman with a 54-mm infrarenal abdominal aortic aneurysm underwent endovascular repair using an iliac side branch device for accessory renal artery salvage. The procedure was technically successful, and no immediate perioperative adverse events were encountered. The creatinine level increased slightly. Six-month follow-up imaging revealed no endoleaks or occlusion. Conclusion: Considering the higher perioperative risk associated with open or hybrid procedures for similar cases, this off-label application of a well-recognized endovascular device deserves consideration as an alternative treatment option.

Systematic Review and Meta-Regression of Factors Affecting Midline Incisional Hernia Rates: Analysis of 14,618 Patients

BACKGROUND

The incidence of incisional hernias (IHs) following midline abdominal incisions is difficult to estimate. Furthermore recent analyses have reported inconsistent findings on the superiority of absorbable versus non-absorbable sutures.

OBJECTIVE

To estimate the mean IH rate following midline laparotomy from the published literature, to identify variables that predict IH rates and to analyse whether the type of suture (absorbable versus non-absorbable) affects IH rates.

METHODS

We undertook a systematic review according to PRISMA guidelines. We sought randomised trials and observational studies including patients undergoing midline incisions with standard suture closure. Papers describing two or more arms suitable for inclusion had data abstracted independently for each arm.

RESULTS

Fifty-six papers, describing 83 separate groups comprising 14,618 patients, met the inclusion criteria. The prevalence of IHs after midline incision was 12.8% (range: 0 to 35.6%) at a weighted mean of 23.7 months. The estimated risk of undergoing IH repair after midline laparotomy was 5.2%. Two meta-regression analyses (A and B) each identified seven characteristics associated with increased IH rate: one patient variable (higher age), two surgical variables (surgery for AAA and either surgery for obesity surgery (model A) or using an upper midline incision (model B)), two inclusion criteria (including patients with previous laparotomies and those with previous IHs), and two circumstantial variables (later year of publication and specifying an exact significance level). There was no significant difference in IH rate between absorbable and non-absorbable sutures either alone or in conjunction with either regression analysis.

CONCLUSIONS

The IH rate estimated by pooling the published literature is 12.8% after about two years. Seven factors account for the large variation in IH rates across groups. However there is no evidence that suture type has an intrinsic effect on IH rates.

Visceral obesity, not elevated BMI, is strongly associated with incisional hernia after colorectal surgery

BACKGROUND

High BMI is often used as a proxy for obesity and has been considered a risk factor for the development of an incisional hernia after abdominal surgery. However, BMI does not accurately reflect fat distribution.

OBJECTIVE

The purpose of this work was to investigate the relationship among different obesity measurements and the risk of incisional hernia.

DESIGN

This was a retrospective cohort study.

SETTINGS

The study included a single academic institution in New York from 2003 to 2010.

PATIENTS

The study consists of 193 patients who underwent colorectal cancer resection.

MAIN OUTCOME MEASURES

Preoperative CT scans were used to measure visceral fat volume, subcutaneous fat volume, total fat volume, and waist circumference. A diagnosis of incisional hernia was made either through physical examination in medical chart documentation or CT scan.

RESULTS

Forty-one patients (21.2%) developed an incisional hernia. The median time to hernia was 12.4 months. After adjusting for patient and surgical characteristics using Cox regression analysis, visceral obesity (HR 2.04, 95% CI 1.07-3.91) and history of an inguinal hernia (HR 2.40, 95% CI 1.09-5.25) were significant risk factors for incisional hernia. Laparoscopic resection using a transverse extraction site led to a >75% reduction in the risk of incisional hernia (HR 0.23, 95% CI 0.07-0.76). BMI > 30 kg/m was not significantly associated with incisional hernia development.

LIMITATIONS

Limitations include the retrospective design without standardized follow-up to detect hernias and the small sample size attributed to inadequate or unavailable CT scans.

CONCLUSIONS

Visceral obesity, history of inguinal hernia, and location of specimen extraction site are significantly associated with the development of an incisional hernia, whereas BMI is poorly associated with hernia development. These findings suggest that a lateral transverse location is the incision site of choice and that new strategies, such as prophylactic mesh placement, should be considered in viscerally obese patients.

Prevention of incisional hernias: how to close a midline incision

The development of wound complications is closely related to the surgical technique at wound closure. The risk of the suture technique affecting the development of wound dehiscence and incisional hernia can be monitored through the suture length to wound length ratio. Midline incisions should be closed in one layer by a continuous-suture technique using a monofilament suture material tied with self-locking knots. Excessive tension should not be placed on the suture. Closure must always be with a suture length to wound length ratio higher than 4.

Elective treatment of abdominal aortic aneurysm is reasonable in patients >85 years of age

BACKGROUND

The numbers of patients >85 years of age referred for abdominal aortic aneurysm (AAA) repair have increased in recent decades. With the population aging, increased screening of AAA, and introduction of less invasive surgical techniques, vascular surgeons will be treating more elderly patients. Few data are available for estimating the risks and benefits of prophylactic repair among those with such an advanced age. The aim of this single-center study was to evaluate the short-term to midterm results after AAA repair in patients >85 years of age.

METHODS

Between 2004 and 2012, data of patients >85 years old who required an elective AAA repair at our institution were collected prospectively. According to the current guidelines, patients underwent endovascular aneurysm repair (EVAR) each time the aortic anatomy was suitable. Open repair (OR) was performed in those patients with hostile proximal neck anatomy and/or severe iliac tortuosity. Type of repair (EVAR or OR) and perioperative and midterm outcomes were analyzed. Primary end points were 30-day mortality and midterm survival.

RESULTS

Among 1016 patients undergoing elective AAA repair during the study period, 59 (5.8%) were ≥85 years of age (54 men, mean age 87 ± 2 years), with a mean aneurysm diameter of 61.5 ± 20.3 mm. Thirty-three patients (56%) underwent EVAR and 26 (44%) had an OR. Thirty-day mortality was 6.7% (6% with EVAR and 7.6% with OR, P <0.05). Mean follow-up was 24.7 ± 18 months. Kaplan‒Meier analyses for survival were 85.5%, 64.5%, and 50% at 1, 3, and 5 years, respectively. No aneurysm-related death was observed during follow-up.

CONCLUSION

Elective repair may be proposed in patients >85 years of age in cases of threatening AAA, showing acceptable perioperative mortality and reasonable midterm survival results. Even if EVAR did not seem to offer significant benefits in perioperative mortality in our study, it appears reasonable to suggest this less invasive technique as first-line treatment in cases of suitable anatomy in such an advanced-age population.

Lack of association between inguinal hernia and abdominal aortic aneurysm in a population-based male cohort

Background

Previous studies have reported a higher prevalence of inguinal hernia in patients with abdominal aortic aneurysm (AAA). The aim of this study was to explore the association between inguinal hernia and AAA in a large population-based cohort of men who had screening for AAA.

Methods

A total of 18 331 men aged 65–76 years had ultrasound screening for AAA in the Central Region of Denmark from 2008 to 2010. The Danish National Patient Registry was interrogated, and screened men registered with an inguinal hernia from 1977 to 2011 were identified. The association between inguinal hernia and AAA was assessed by multiple logistic regression analysis.

Results

The prevalence of AAA was 3.3 per cent (601 of 18 331). A total of 2936 (16.0 per cent) of the 18 331 patients were registered with a diagnosis of inguinal hernia or hernia repair. Inguinal hernia was not associated with AAA: crude odds ratio (OR) 0.86 (95 per cent confidence interval 0.68 to 1.09) and adjusted OR 0.94 (0.75 to 1.20).

Conclusion

In contrast to smaller patient-based studies, this large population-based study found no association between inguinal hernia and AAA.

Circulating levels of matrix metalloproteinases and tissue inhibitors of metalloproteinases in patients with incisional hernia

Incisional hernia formation is a common complication to laparotomy and possibly associated with alterations in connective tissue metabolism. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are closely involved in the metabolism of the extracellular matrix. Our aim was to study serum levels of multiple MMPs and TIMPs in patients with and without incisional hernia. Out of 305 patients who underwent laparotomy, 79 (25.9%) developed incisional hernia over a median follow-up period of 3.7 years. Pooled sera from a subset (n = 72) of these patients were screened for MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-12, MMP-13, TIMP-1, TIMP-2, and TIMP-4 using a multiplex sandwich fluorescent immunoassay supplemented with gelatin zymography. The screening indicated differences in serum MMP-9 and TIMP-1 levels. Consequently, MMP-9 and TIMP-1 levels were measured in serum in the whole patient cohort with enzyme-linked immunosorbent assay. There were no significant differences in either MMP-9 (p = 0.411) or TIMP-1 (p = 0.679) levels between hernia and hernia-free patients. MMP-9 was significantly increased in smokers compared with nonsmokers (p = 0.016). In conclusion, a possible involvement of MMPs and TIMPs in the pathogenesis of incisional hernia formation was not reflected systemically.

Risk of late-onset adhesions and incisional hernia repairs after surgery

BACKGROUND

Long-term adhesion-related complications and incisional hernias after abdominal surgery are common and costly. There are few data on the risk of these complications after different abdominal operations.

STUDY DESIGN

We identified Medicare beneficiaries who underwent endovascular repair of an abdominal aortic aneurysm from 2001-2008 who presumably are not at risk for laparotomy-related complications. We identified all laparoscopic and open operations involving the abdomen, pelvis, or retroperitoneum and categorized them into 5 groups according to invasiveness. We then identified laparotomy-related complications for up to 5 years after the index operation and compared these with the baseline rate of complications in a control group of patients who did not undergo an abdominal operation.

RESULTS

We studied 85,663 patients, 7,513 (8.8%) of which underwent a laparotomy, including 2,783 major abdominal operations, 709 minor abdominal operations, 963 ventral hernia repairs, 493 retroperitoneal/pelvic operations, and 2,565 laparoscopic operations. Mean age was 76.7 years and 82.0% were male. Major abdominal operations carried the highest risk for adhesion-related complications (14.3% and 25.0% at 2 and 5 years compared with 4.0% and 7.8% for the control group; p < 0.001) and incisional hernias (7.8% and 12.0% compared with 0.6% and 1.2% for the control group; p < 0.001). Laparoscopic operations (4.6% and 10.7% for adhesions, 1.9% and 3.2% for incisional hernias) carried the lowest risk.

CONCLUSIONS

Late-onset laparotomy-related complications are frequent and their risk extends through 5 years beyond the perioperative period. With the advancement and expansion of laparoscopic techniques and its attendant lower risk for long-term complications, these results can alter the risk-to-benefit profile of various types of abdominal operations and can also strengthen the rationale for additional development of laparoscopic approaches to abdominal operations.

Incisional hernia postrepair of abdominal aortic occlusive and aneurysmal disease: five-year incidence

The aim of this study was to report the five-year incidence of incisional hernia after vascular repair of abdominal aortic occlusive (AOD) and aneurysmal disease (AAA), and to determine the factors associated with the development of this complication. Consecutive patients who underwent AAA and AOD at the University of Manitoba, Canada, between January 1999 and December 2002, were recruited and evaluated by clinical examination one week, one month and six months after the surgery, and through medical records review thereafter. The development of postoperative incisional hernia was recorded and analyzed. Two-hundred four patients, with a mean age of 70.1 years, provided consent for the study. The overall five-year incidence of incisional hernia was 69.1% and the overall median failure time was 48 months. The median failure time was 48 months for AOD and 36 months for AAA (P < 0.01). The urgent and ruptured AAA repair had a higher five-year incidence of incisional hernia as compared with AOD or elective AAA repair (P < 0.01). A history of bilateral inguinal hernia was significantly associated with incisional hernia (P < 0.05). Men and patients who were 65 years and older had a higher five-year incidence of incisional hernia (P < 0.01). Age ≥65 years, male gender, hypertension and past bilateral inguinal hernia repair double the risk for the development of incisional hernia (hazard ratio = 2.1. 2.2, 1.7 and 2.8, respectively). In conclusion, the five-year incidence of incisional hernia after vascular repair of AOD or AAA is 69.1%, and tends to occur late after vascular repair.

Hérnias incisionais no pós-operatório de correção de aneurisma de aorta abdominal

CONTEXTO: A incidência de hérnia incisional no pós-operatório da correção aberta de aneurisma de aorta abdominal é alta, variando de 10 a 37% e mais de três vezes mais comum do que em pacientes submetidos à correção para doença obstrutiva aorto-ilíaca. OBJETIVO: Apresentar a incidência de hérnia incisional em um grupo de pacientes acompanhados no pós-operatório da correção aberta de aneurisma de aorta abdominal. MÉTODOS: Série de casos em uma população de 144 pacientes operados por aneurisma de aorta abdominal, entre junho de 1989 e junho de 2010, e que estão em acompanhamento regular no Ambulatório de Moléstias Vasculares. RESULTADOS: O seguimento médio dos pacientes foi de 63 meses (1 a 238). A idade média foi de 67 anos (45 a 91) e o tamanho médio dos aneurismas foi de 6,54 cm. Foram realizadas 130 laparotomias medianas xifo-púbicas e 13 acessos extraperitoniais pelo flanco esquerdo. Nestes pacientes, a incidência de hérnia incisional foi de 18,5 e 7,7%, respectivamente, para incisões na linha média ou no flanco (p=0,315). Um paciente apresentou abaulamento da musculatura oblíqua por denervação. Foi realizada uma laparotomia transversa, que não apresentou hérnia no pós-operatório tardio. CONCLUSÕES: A incidência de hérnia incisional na cirurgia aberta para correção de aneurisma de aorta abdominal é alta, ocorre com maior frequência em incisões da linha média e tem relação direta com a técnica empregada para o fechamento da aponeurose, exigindo do cirurgião atenção especial para este tempo cirúrgico para evitar a causa mais comum de reoperação em tal grupo de pacientes.