Nadia A. Henriksen

Connective tissue alteration in abdominal wall hernia.

The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations in abdominal wall hernia formation.

Risk factors for incisional hernia repair after aortic reconstructive surgery in a nationwide study

OBJECTIVE Abdominal aortic aneurysm disease has been hypothesized as associated with the development of abdominal wall hernia. We evaluated the risk factors for incisional hernia repair after open elective aortic reconstructive surgery for aortoiliac occlusive disease and abdominal aortic aneurysm. METHODS A retrospective analysis of prospectively recorded data in nationwide databases was carried out, with merged data from the Danish Vascular Registry (January 2006-January 2012), the Danish Ventral Hernia Database (January 2007-January 2012), and the Danish National Patient Register (January 2007-January 2012) to obtain 100% follow-up for incisional hernia repair in patients undergoing open elective aortic reconstructive surgery. The predefined risk factors of age, sex, American Association of Anesthesiologists score, body mass index, smoking status, type of aortic surgery, and type of incision were tested in a multivariate Cox regression model for the risk of incisional hernia repair. RESULTS We identified 2597 patients, of whom 838 and 1759 underwent open elective surgery for an aortoiliac occlusive disease and abdominal aortic aneurysm, respectively. The median follow-up was 28.9 months (range, 0-71.6 months), and the cumulative risk of hernia repair after aortic reconstructive surgery was 10.4% after 6 years of follow-up. Body mass index >25.0 kg/m(2) (adjusted hazard ratio, 1.74; 95% confidence interval, 1.21-2.46) and abdominal aortic aneurysm repair (adjusted hazard ratio, 1.58; 95% confidence interval, 1.06-2.35) were significantly associated with incisional hernia repair. CONCLUSIONS High body mass index and abdominal aortic aneurysm repair were independent risk factors for a subsequent incisional hernia surgery in patients undergoing aortic reconstructive surgery.

The collagen turnover profile is altered in patients with inguinal and incisional hernia

BACKGROUND Disturbed metabolism in the extracellular matrix (ECM) contributes to formation of abdominal wall hernias. The aim of this study was to gain deeper insight into the ECM turnover in hernia patients by analyzing serum biomarkers specifically reflecting collagen synthesis and breakdown in the interstitial matrix (types I, III, and V collagens) and in the basement membrane (type IV collagen). MATERIAL AND METHODS Patients with 3 different types of hernias were included: Primary unilateral inguinal hernia (n = 17), multiple hernias defined as ≥3 hernias (n = 21), and incisional hernia (n = 25). Patients without hernias scheduled to undergo elective operation for gallstones (n = 18) served as controls. Whole venous blood was collected preoperatively. Biomarkers for synthesis of interstitial matrix (PINP, Pro-C3, P5CP) and basement membrane (P4NP) as well as corresponding degradation (C1M, C3M, C5M, and C4M) were measured in serum by validated, solid-phase competitive assays. RESULTS In inguinal hernia patients, the turnover of the interstitial matrix collagens type III (P < .042) and V (P < .001) was decreased compared with controls, whereas the turnover of the basement membrane collagen type IV was increased (P < .001). In incisional hernia patients, the turnover of type V collagen was decreased (P = .048) and the turnover of type IV collagen was increased compared with the hernia-free controls (P < .001). CONCLUSION Hernia patients demonstrated systemically altered collagen metabolism. The serologic turnover profile of type IV collagens may predict the presence of inguinal and incisional hernia. Regulation of type IV collagen turnover may be crucial for hernia development.

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

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.

Abdominal wall hernia and pregnancy: a systematic review

PurposeThere is no consensus as to the treatment strategy for abdominal wall hernias in fertile women. This study was undertaken to review the current literature on treatment of abdominal wall hernias in fertile women before or during pregnancy.MethodsA literature search was undertaken in PubMed and Embase in combination with a cross-reference search of eligible papers.ResultsWe included 31 papers of which 23 were case reports. In fertile women undergoing sutured or mesh repair, pain was described in a few patients during the last trimester of a subsequent pregnancy. Emergency surgery of incarcerated hernias in pregnant women, as well as combined hernia repair and cesarean section appears as safe procedures. No major complications were reported following hernia repair before or during pregnancy. The combined procedure of elective cesarean section and abdominal wall hernia repair was reported in 102 patients without major complications.ConclusionsThe literature on abdominal wall hernia and pregnancy is sparse. Abdominal wall hernia repair with suture or mesh may cause pain in the last trimester of a subsequent pregnancy. Hernia repair in conjunction with cesarean section appear as the optimal treatment of a pregnant patient with a symptomatic abdominal wall hernia.

Cost assessment of instruments for single-incision laparoscopic cholecystectomy.

This study concludes that a modified single-incision procedure for cholecystectomy using 2 regular ports inserted through the umbilicus can be performed at lower cost than a conventional 4-port procedure.

Multicenter data acquisition made easy

BackgroundThe process for data collection in multicenter trials may be troublesome and expensive. We report our experience with the spreadsheet function in Googledocs for this purpose.MethodsIn Googledocs the data manager creates a form similar to the paper case record form, which will function as a decentral data entry module. When the forms are submitted, they are presented in a spreadsheet in Googledocs, which can be exported to different standard spreadsheet formats.ResultsFor a multicenter randomized clinical trial with five different participating hospitals we created a decentral data entry module using the spreadsheet function in Googledocs. The study comprised 332 patients (clinicaltrials.gov identifier: NCT00815698) with five visits per patient. One person at each study site entered data from the original paper based case report forms which were kept at the study sites as originals. We did not experience any technical problems using the system.ConclusionsThe system allowed for decentral data entry, and it was easy to use, safe, and free of charge. The spreadsheet function in Googledocs may potentially replace current expensive solutions for data acquisition in multicenter trials.Trial registrationclinicaltrials.gov NCT00815698

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.

Inguinal Hernia Epidemiology

Inguinal hernia is the most common abdominal wall hernia. Although 50 % of patients with an inguinal hernia are unaware of this, repair of inguinal hernia is one of the most commonly performed surgical procedures worldwide. Inguinal hernias occur more often in men and with increasing incidence at advanced age. The lifetime risk of developing inguinal hernia is approximately 25 % for men. Development of inguinal hernia is associated with several factors of which inheritance predominates. Low body mass index, chronic constipation, Ehlers–Danlos syndrome, and prostatectomy are additional risk factors, whereas it is still debatable if certain occupations influence on inguinal hernia formation. The recurrence rate after inguinal hernia repair is 3–8 %. Experienced surgeons and those with more than five procedures yearly have fewer recurrences. A number of intraoperative aspects are related to hernia recurrence. Finally, obesity and smoking are patient-related factors that increase the risk of inguinal hernia recurrence.

Type V Collagen is Persistently Altered after Inguinal Hernia Repair

Background and Aims: Hernia formation is associated with alterations of collagen metabolism. Collagen synthesis and degradation cause a systemic release of products, which are measurable in serum. Recently, we reported changes in type V and IV collagen metabolisms in patients with inguinal and incisional hernia. The aim of this study was to determine if the altered collagen metabolism was persistent after hernia repair. Material and Methods: Patients who had undergone repairs for inguinal hernia (n = 11) or for incisional hernia (n = 17) were included in this study. Patients who had undergone elective cholecystectomy served as controls (n = 10). Whole venous blood was collected 35–55 months after operation. Biomarkers for type V collagen synthesis (Pro-C5) and degradation (C5M) and those for type IV collagen synthesis (P4NP) and degradation (C4M2) were measured by a solid-phase competitive assay. Results: The turnover of type V collagen (Pro-C5/C5M) was slightly higher postoperatively when compared to preoperatively in the inguinal hernia group (P = 0.034). In addition, the results revealed a postoperatively lower type V collagen turnover level in the inguinal hernia group compared to controls (P = 0.012). In the incisional hernia group, the type V collagen turnover was higher after hernia repair (P = 0.004) and the postoperative turnover level was not different from the control group (P = 0.973). Conclusion: Patients with an inguinal hernia demonstrated a systemic and persistent type V collagen turnover alteration. This imbalance of the collagen metabolism may be involved in the development of inguinal hernias.