Addition of rectus sheath relaxation incisions to emergency midline laparotomy for peritonitis to prevent fascial dehiscence

The clinical consequences of burst abdomen after emergency midline laparotomy: a prospective, observational cohort study

PURPOSE

The emergency midline laparotomy is a commonly performed procedure with a burst abdomen being a critical surgical complication requiring further emergency surgery. This study aimed to investigate the clinical outcomes of patients with burst abdomen after emergency midline laparotomy.

METHODS

A single-center, prospective, observational cohort study of patients undergoing emergency midline laparotomy during a two-year period was done. Abdominal wall closure followed a standardized technique using monofilament, slowly absorbable suture in a continuous suturing technique with a suture-to-wound ratio of at least 4:1. Treatment of burst abdomen was surgical. Data, including intra-hospital postoperative complications, were collected and registered chronologically based on journal entries. The primary outcome was to describe postoperative complications, length of stay, and the overall morbidity based on the Comprehensive Complication Index (CCI), stratified between patients who did and did not suffer from a burst abdomen during admission.

RESULTS

A total of 543 patients were included in the final cohort, including 24 patients with burst abdomen during admission. The incidence of burst abdomen after emergency midline laparotomy was 4.4%. Patients with a burst abdomen had a higher total amount of complications per patient (median of 3, IQR 1.3-5.8 vs. median of 1, IQR 0.0-3.0; p = 0.001) and a significantly higher CCI (median of 53.0, IQR 40.3-94.8 vs. median of 21.0, IQR 0.0-42.0; p =  < 0.001).

CONCLUSION

Patients with burst abdomen had an increased risk of postoperative complications during admission as well as a longer and more complicated admission with multiple non-surgical complications.

Abdominal wound dehiscence and incisional hernia prevention in midline laparotomy: a systematic review and network meta-analysis

BACKGROUND

Incisional hernia (IH) is the main complication after laparotomy. In an attempt to reduce this complication, mesh techniques and studies in which the closure technique is modified have been proposed. Both types are characterized by comparison with the closure described as standard or conventional: 1 × 1, mass, and continuous closure. For this study, modified closure techniques (MCTs) were considered as those techniques in which an extra suture is placed (reinforced tension line (RTL), retention), the closure point is modified in distance (small bites) or shape (CLDC, Smead Jones, interrupted, Cardiff point) and which aim to reduce these complications. The objective of this network meta-analysis (NMA) was to evaluate the effectiveness of MCTs for reducing the incidence of IH and abdominal wound dehiscence (AWD) to provide objective support for their recommendation.

METHODS

An NMA was performed according to the PRISMA-NMA guidelines. The primary objective was to determine the incidence of IH and AWD, and the secondary objective was to determine the incidence of postoperative complications. Only published clinical trials were included. The risk of bias was analyzed, and the random-effects model was used to determine statistical significance.

RESULTS

Twelve studies comparing 3540 patients were included. The incidence of HI was lower in RTL, retention suture, and small bites, these techniques showed statistical differences with pooled ORs (95% CI) of 0.28 (0.09-0.83), 0.28 (0.13-0.62), and 0.44 (0.31-0.62), respectively. Associated complications, including hematoma, seroma, and postoperative pain, could not be analyzed; however, MCTs did not increase the risk of surgical site infection.

CONCLUSION

Small bites, RTL, and retention sutures decreased the prevalence of IH. RTL and retention suture decreased the prevalence of AWD. RTL was the best technique as it reduced both complications (IH and AWD) and had the best SUCRA and P-scores, and the number needed to treat (NNT) for net effect was 3.

REGISTRATION

This study was prospectively registered in the PROSPERO database under registration number CRD42021231107.

Rectus diastasis increases risk of burst abdomen in emergency midline laparotomies: a matched case–control study

PURPOSE

Burst abdomen is a serious complication requiring immediate surgical treatment. This study aimed to investigate the association between rectus diastasis and burst abdomen in patients undergoing emergency midline laparotomy.

METHODS

A single-center, retrospective, matched case-control study of patients undergoing emergency midline laparotomy from May 2016 to August 2021 was conducted. Cases (patients who suffered from burst abdomen) were matched 1:4 with controls based on age and sex. Rectus diastasis was evaluated on CT imaging and was defined as a distance of at least three centimeters between the rectus abdominis muscles, three centimeters above the umbilicus. Midline laparotomy aponeurosis closure was standardized during the study period, using a slowly absorbable suture, sutured continuously with small bites of five millimeters and a minimum suture-to-wound ratio of 4:1. The primary outcome was the association between rectus diastasis and burst abdomen, evaluated against other suspected risk factors including obesity, liver cirrhosis, previous laparotomy, midline hernias and active smoking in a multivariate analysis.

RESULTS

A total of 465 patients were included in the study, with 93 cases matched to 372 controls. Eighty-four patients had rectus diastasis (35.5% cases vs. 13.7% controls; p =  < 0.001). Multivariate analysis found rectus diastasis significantly associated with burst abdomen (OR 3.06, 95% CI 1.71-5.47; p =  < 0.001). No other suspected risk factors showed a significant association with burst abdomen.

CONCLUSION

Rectus diastasis was highly associated with an increased risk of burst abdomen after emergency midline laparotomy.

Abdominal subcutaneous obesity and the risk of burst abdomen: a matched case-control study

PURPOSE

The causes of burst abdomen after midline laparotomy remain uncertain. Obesity is a suspected risk factor. The purpose of this study was to investigate the association between abdominal subcutaneous obesity (ASO) and burst abdomen in patients undergoing emergency midline laparotomy.

METHODS

We conducted a single-centre, retrospective, matched case-control study of patients undergoing emergency midline laparotomy from May 2016 to August 2021. Patients suffering from burst abdomen were matched 1:4 with controls based on age and sex. Abdominal wall closure was standardized in the study period with the small bites, small stitches technique. ASO was defined as the highest sex-specific quartile (≥ 75%) of subcutaneous fat layer evaluated on CT. The primary outcome was the association between ASO and burst abdomen, stratified between cases and controls. Secondary outcomes included 30- and 90-day mortality, length of stay, and suspected risk factors of burst abdomen, assessed by multivariate analysis across cases and controls.

RESULTS

A total of 475 patients were included in this study, with 95 cases matched to 380 controls. Liver cirrhosis, active smoking, and high alcohol consumption were more common among cases in an unadjusted analysis. Liver cirrhosis (odds ratio (OR) 3.32, p = 0.045) and active smoking (OR 1.98, p = 0.009) remained significant in a multivariate analysis and were associated with burst abdomen. One hundred twenty-four patients had ASO. ASO was not significantly associated with burst abdomen (OR 1.11, p = 0.731).

CONCLUSION

ASO was not found to be associated with an increased risk of burst abdomen after emergency midline laparotomy.

Complications and Their Association with Mortality Following Emergency Gastrointestinal Surgery-an Observational Study

PURPOSE

Emergency gastrointestinal surgery is followed by a high risk of major complications and death. This study aimed to investigate which complications showed the strongest association with death following emergency surgery for gastrointestinal obstruction or perforation.

METHODS

We retrospectively included adults who had undergone emergency gastrointestinal surgery for radiologically verified obstruction or perforation at three Danish hospitals between 2014 and 2015. The exposure variables comprised 16 predefined Clavien-Dindo-graded complications. Cox regression with delayed entry was used to analyze the association of these complications with 90-day mortality. We adjusted for hospital, age, American Society of Anesthesiologists classification, pre-operative Sepsis-2 score, cardiac comorbidity, renal comorbidity, hypertension, active cancer, bowel obstruction or perforation, and the surgical procedure. Subgroup analyses were done for patients with gastrointestinal obstruction or perforation.

RESULTS

Of the 349 included patients, 281 (80.5%) experienced at least one complication. The risk of death was 20.6% (14) for patients with no complications and varied between 21 and 57% for patients with complications. Renal impairment (hazard ratio (HR): 6.8 (95%CI: 3.7-12.4)), arterial thromboembolic events (HR 4.8 (2.3-9.9)), and atrial fibrillation (HR 4.4 (2.8-6.8)) showed the strongest association with 90-day mortality. Atrial fibrillation was the only complication significantly associated with death in patients with gastrointestinal obstruction as well as perforation.

CONCLUSION

This study of patients undergoing emergency gastrointestinal surgery revealed that renal impairment, arterial thromboembolic events, and atrial fibrillation had the strongest association with death. Atrial fibrillation may serve as an in-situ marker of patients needing escalation of care.

"Sarcopenia is associated with increased risk of burst abdomen after emergency midline laparotomy: a matched case-control study"

PURPOSE

Burst abdomen is a serious complication commonly observed after emergency midline laparotomy. Sarcopenia has been associated with increased morbidity and mortality after abdominal surgery. This single-center, retrospective, matched case-control study aimed to investigate the association between sarcopenia and burst abdomen in patients undergoing emergency midline laparotomy.

METHODS

Patients who had burst abdomen after emergency midline laparotomy were matched 1:4 with controls based on age and sex. Abdominal wall closure was standardized in the study period with the small bites, small stitches technique. CT assessed psoas cross-sectional area was used as a surrogate measure of sarcopenia. Sarcopenia was defined as the sex-specific lowest quartile of psoas cross-sectional area adjusted for body surface area. The primary outcome was the incidence rate of sarcopenia amongst cases and controls. Secondary outcomes were risk factors for burst abdomen and death that were identified using multivariate logistic regression analysis.

RESULTS

67 cases were matched to 268 controls during May 2016-December 2019. BMI > 30 kg/m², liver cirrhosis, smoking, high ASA score and peritonitis were more frequently observed among cases. Multivariate analysis revealed that sarcopenia (odds ratio (OR) 2.3, p = 0.01), active smoking (OR 2.3, p = 0.006) and liver cirrhosis (OR 3.7, p = 0.042) were significantly associated with burst abdomen. ASA score ≥ 3 (OR 5.5, p = 0.001) and ongoing malignant disease (OR 3.2, p = 0.001) were significantly associated with increased 90-day mortality.

CONCLUSION

Sarcopenia is associated with increased risk of burst abdomen after midline laparotomy. Prospective trials are needed.

High rate of incisional hernia observed after mass closure of burst abdomen

PURPOSE

This study investigated the long-term development of incisional hernia after implementation of a standardized surgical treatment strategy for burst abdomen in abdominal midline incisions with a continuous mass closure technique.

METHODS

The study was a single-center, observational study evaluating all patients treated for burst abdomen between June 2014 and April 2019 with a long-term follow-up in October 2020. In June 2014, a standardized surgical treatment for burst abdomen involving a monofilament, slowly absorbable suture in a continuous mass-closure stitch with large bites of 3 cm and small steps of 5 mm was introduced. The occurrence of incisional hernia was investigated and defined as a radiological-, clinical-, or intraoperative finding of a hernia in the abdominal midline incision at follow-up.

RESULTS

Ninety-four patients suffered from burst abdomen during the study period. Eighty patients were eligible for follow-up. The index surgery prior to burst abdomen was an emergency laparotomy in 78% (62/80) of the patients. Nineteen patients died within the first 30 postoperative days and 61 patients were available for further analysis. The long-term incisional hernia rate was 33% (20/61) with a median follow-up of 17 months (min 4, max 67 months).

CONCLUSION

Standardized surgery for burst abdomen with a mass-closure technique using slow absorbable running suture results in high rates of long-term incisional hernias, comparable to the hernia rates reported in the literature among this group of patients.

Standardized Surgical Primary Repair for Burst Abdomen Reduces the Risk of Fascial Redehiscence

OBJECTIVE

To determine whether a standardized surgical primary repair for burst abdomen could lower the rate of fascial redehiscence.

SUMMARY BACKGROUND DATA

Burst abdomen after midline laparotomy is associated with increased morbidity and mortality. The surgical treatment is poorly investigated but known for a poor outcome with high rates of re-evisceration (redehiscence).

METHODS

This study was a single-center, interventional study comparing rates of fascial redehiscence after surgery for burst abdomen in a study cohort (July 2014-April 2019) to a historical cohort (January 2009-December 2013). A standardized surgical strategy was introduced for burst abdomen: The abdominal wall was closed using a slowly absorbable running suture in a mass closure technique with "large bites" of 3 cm in "small steps" of 5 mm, in an approximate wound-suture ratio of 1:10. Demographics, comorbidities, preceding type of surgery, and surgical technique were registered. The primary outcome was fascial redehiscence. The secondary outcome was 30- and 90-day mortality.

RESULTS

The study included 186 patients with burst abdomen (92 patients in the historical cohort vs 94 patients in the study cohort). No difference in sex, performance status, comorbidity, or body mass index was found. In 77% of the historical cohort and 80% of the study cohort, burst abdomen occurred after emergency laparotomy (P = 0.664). The rate of redehiscence was reduced from 13% (12/92 patients) in the historical cohort to 4% (4/94 patients) in the study cohort (P = 0.033). There was no difference in 30- or 90-day mortality.

CONCLUSION

Standardized surgical primary repair for burst abdomen reduced the rate of fascial redehiscence.

Relaxation incisions and tensile strength in the abdominal wall of pigs

Purpose

To analyze the resistance to medial traction of abdominal wall muscles, before and after performing relaxing incisions.

Methods

Seventeen live pigs were used. After a median laparotomy, the handles were made in the rectus abdominis muscles (RAM) to fit the dynamometer. Step 1 (control phase): tensile strength measured without performing relaxant incisions. Step 2: A curvilinear relaxant incision was made on the anterior blade of the right RAM sheath and then the tensile strength was measured by the edge of the wound. The same procedure was adopted after incision of the left posterior blade. Step 3: Relaxing incisions were made in the right posterior and left anterior blade, so that both sides were left with a relaxing incision on both blades. Measurements of resistance were performed.

Results

There was no statistically significant difference between the sides. On the right and left side, all treatments reduced the tensile strength when compared to each other and to the control. There was a reduction of 12% and 9.8% after incision of the anterior and posterior blade, respectively.

Conclusion

Relaxing incisions reduced tensile strength in the ventral abdominal wall.

Closure methods for laparotomy incisions for preventing incisional hernias and other wound complications

BACKGROUND

Surgeons who perform laparotomy have a number of decisions to make regarding abdominal closure. Material and size of potential suture types varies widely. In addition, surgeons can choose to close the incision in anatomic layers or mass ('en masse'), as well as using either a continuous or interrupted suturing technique, of which there are different styles of each. There is ongoing debate as to which suturing techniques and suture materials are best for achieving definitive wound closure while minimising the risk of short- and long-term complications.

OBJECTIVES

The objectives of this review were to identify the best available suture techniques and suture materials for closure of the fascia following laparotomy incisions, by assessing the following comparisons: absorbable versus non-absorbable sutures; mass versus layered closure; continuous versus interrupted closure techniques; monofilament versus multifilament sutures; and slow absorbable versus fast absorbable sutures. Our objective was not to determine the single best combination of suture material and techniques, but to compare the individual components of abdominal closure.

SEARCH METHODS

On 8 February 2017 we searched CENTRAL, MEDLINE, Embase, two trials registries, and Science Citation Index. There were no limitations based on language or date of publication. We searched the reference lists of all included studies to identify trials that our searches may have missed.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared suture materials or closure techniques, or both, for fascial closure of laparotomy incisions. We excluded trials that compared only types of skin closures, peritoneal closures or use of retention sutures.

DATA COLLECTION AND ANALYSIS

We abstracted data and assessed the risk of bias for each trial. We calculated a summary risk ratio (RR) for the outcomes assessed in the review, all of which were dichotomous. We used random-effects modelling, based on the heterogeneity seen throughout the studies and analyses. We completed subgroup analysis planned a priori for each outcome, excluding studies where interventions being compared differed by more than one component, making it impossible to determine which variable impacted on the outcome, or the possibility of a synergistic effect. We completed sensitivity analysis, excluding trials with at least one trait with high risk of bias. We assessed the quality of evidence using the GRADEpro guidelines.

MAIN RESULTS

Fifty-five RCTs with a total of 19,174 participants met the inclusion criteria and were included in the meta-analysis. Included studies were heterogeneous in the type of sutures used, methods of closure and patient population. Many of the included studies reported multiple comparisons.For our primary outcome, the proportion of participants who developed incisional hernia at one year or more of follow-up, we did not find evidence that suture absorption (absorbable versus non-absorbable sutures, RR 1.07, 95% CI 0.86 to 1.32, moderate-quality evidence; or slow versus fast absorbable sutures, RR 0.81, 95% CI 0.63 to 1.06, moderate-quality evidence), closure method (mass versus layered, RR 1.92, 95% CI 0.58 to 6.35, very low-quality evidence) or closure technique (continuous versus interrupted, RR 1.01, 95% CI 0.76 to 1.35, moderate-quality evidence) resulted in a difference in the risk of incisional hernia. We did, however, find evidence to suggest that monofilament sutures reduced the risk of incisional hernia when compared with multifilament sutures (RR 0.76, 95% CI 0.59 to 0.98, I2 = 30%, moderate-quality evidence).For our secondary outcomes, we found that none of the interventions reduced the risk of wound infection, whether based on suture absorption (absorbable versus non-absorbable sutures, RR 0.99, 95% CI 0.84 to 1.17, moderate-quality evidence; or slow versus fast absorbable sutures, RR 1.16, 95% CI 0.85 to 1.57, moderate-quality evidence), closure method (mass versus layered, RR 0.93, 95% CI 0.67 to 1.30, low-quality evidence) or closure technique (continuous versus interrupted, RR 1.13, 95% CI 0.96 to 1.34, moderate-quality evidence).Similarily, none of the interventions reduced the risk of wound dehiscence whether based on suture absorption (absorbable versus non-absorbable sutures, RR 0.78, 95% CI 0.55 to 1.10, moderate-quality evidence; or slow versus fast absorbable sutures, RR 1.55, 95% CI 0.92 to 2.61, moderate-quality evidence), closure method (mass versus layered, RR 0.69, 95% CI 0.31 to 1.52, moderate-quality evidence) or closure technique (continuous versus interrupted, RR 1.21, 95% CI 0.90 to 1.64, moderate-quality evidence).Absorbable sutures, compared with non-absorbable sutures (RR 0.49, 95% CI 0.26 to 0.94, low-quality evidence) reduced the risk of sinus or fistula tract formation. None of the other comparisons showed a difference (slow versus fast absorbable sutures, RR 0.88, 95% CI 0.05 to 16.05, very low-quality evidence; mass versus layered, RR 0.49, 95% CI 0.15 to 1.62, low-quality evidence; continuous versus interrupted, RR 1.51, 95% CI 0.64 to 3.61, very low-quality evidence).

AUTHORS' CONCLUSIONS

Based on this moderate-quality body of evidence, monofilament sutures may reduce the risk of incisional hernia. Absorbable sutures may also reduce the risk of sinus or fistula tract formation, but this finding is based on low-quality evidence.We had serious concerns about the design or reporting of several of the 55 included trials. The comparator arms in many trials differed by more than one component, making it impossible to attribute differences between groups to any one component. In addition, the patient population included in many of the studies was very heterogeneous. Trials included both emergency and elective cases, different types of disease pathology (e.g. colon surgery, hepatobiliary surgery, etc.) or different types of incisions (e.g. midline, paramedian, subcostal).Consequently, larger, high-quality trials to further address this clinical challenge are warranted. Future studies should ensure that proper randomisation and allocation techniques are performed, wound assessors are blinded, and that the duration of follow-up is adequate. It is important that only one type of intervention is compared between groups. In addition, a homogeneous patient population would allow for a more accurate assessment of the interventions.

Wound Disruption Following Colorectal Operations

OBJECTIVES

Postoperative wound disruption is associated with high morbidity and mortality. We sought to identify the risk factors and outcomes of wound disruption following colorectal resection.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was used to examine the clinical data of patients who underwent colorectal resection from 2005 to 2013. Multivariate regression analysis was performed to identify risk factors of wound disruption.

RESULTS

We sampled a total of 164,297 patients who underwent colorectal resection. Of these, 2073 (1.3 %) had wound disruption. Patients with wound disruption had significantly higher mortality (5.1 vs. 1.9 %, AOR: 1.46, P = 0.01). The highest risk of wound disruption was seen in patients with wound infection (4.8 vs. 0.9 %, AOR: 4.11, P < 0.01). A number of factors are associated with wound disruption such as chronic steroid use (AOR: 1.71, P < 0.01), smoking (AOR: 1.60, P < 0.01), obesity (AOR: 1.57, P < 0.01), operation length more than 3 h (AOR: 1.56, P < 0.01), severe Chronic Obstructive Pulmonary Disease (COPD) (AOR: 1.36, P < 0.01), urgent/emergent admission (AOR: 1.31, P = 0.01), and serum Albumin Level <3 g/dL (AOR: 1.27, P < 0.01). Laparoscopic surgery had significantly lower risk of wound disruption compared to open surgery (AOR: 0.61, P < 0.01).

CONCLUSION

Wound disruption occurs in 1.3 % of colorectal resections, and it correlates with mortality of patients. Wound infection is the strongest predictor of wound disruption. Chronic steroid use, obesity, severe COPD, prolonged operation, non-elective admission, and serum albumin level are strongly associated with wound disruption. Utilization of the laparoscopic approach may decrease the risk of wound disruption when possible.

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.

Incisional hernia rate after open abdomen treatment with negative pressure and delayed primary fascia closure

PURPOSE

Various techniques for delayed primary fascia closure have been published in patients treated with open abdomen (OA) and application of negative pressure, but to date, no data are available on incisional hernia (IH) rate. The aim of this retrospective analysis was to investigate the long-term outcome of this patient population with special interest in IH development.

METHODS

Two hundred and nine consecutive patients, 90(43 %) female, were treated at our institution for various abdominal emergencies involving OA from June 2006 to June 2011. Mean age was 63(16-92) years. The indication was abdominal sepsis in 155(74 %) patients, ischemia in 24(12 %) and other reasons in 30(14 %). Hospital mortality was 21 %(n = 44); and planned ventral hernia was 7 %(n = 15); and mortality until follow-up was 16 %(n = 25), and 9 %(n = 13) patients were lost to follow-up, leaving 112 patients for evaluation of IH development.

RESULTS

The rate of IH for patients with OA and delayed primary fascia closure was overall 35 % at a median (range) follow-up time of 26(12-81) months. Mean time for development of a ventral hernia was 11 months; 21(57 %) patients underwent surgery for symptomatic hernia (2 emergency operations for incarceration). Kaplan-Meier estimate for 5 years gave a 66 % IH rate. BMI, small bowel as source of infection and rapid adsorbable interrupted suture were identified risk factors.

CONCLUSION

The rate of IH after open abdomen treatment with delayed primary fascia closure is high with a running suture with slow absorbable suture material showing the best results.

Intraperitoneal mesh implantation for fascial dehiscence and open abdomen

BACKGROUND

Postoperative fascial dehiscence and open abdomen are severe postoperative complications and are associated with surgical site infections, fistula, and hernia formation at long-term follow-up. This study was designed to investigate whether intraperitoneal implantation of a composite prosthetic mesh is feasible and safe.

METHODS

A total of 114 patients with postoperative fascial dehiscence and open abdomen who had undergone surgery between 2001 and 2009 were analyzed retrospectively. Contaminated (wound class 3) or dirty wounds (wound class 4) were present in all patients. A polypropylene-based composite mesh was implanted intraperitoneally in 51 patients, and in 63 patients the abdominal wall was closed without mesh implantation. The primary endpoint was incidence of incisional hernia, and the incidence of enterocutaneous fistula was a secondary endpoint.

RESULTS

The incidence of enterocutaneous fistulas after wound closure post-fascial dehiscence (13% vs. 6% without and with mesh, respectively) or post-open abdomen (22% vs. 28% without and with mesh, respectively) was not significantly different. The incidence of incisional hernia was significantly lower with mesh implantation compared with no-mesh implantation in both contaminated (4% vs. 28%; p = 0.025) and dirty abdominal cavities (5% vs. 34%; p = 0.01).

CONCLUSIONS

Intra-abdominal contamination is not a contraindication for intra-abdominal mesh implantation. The incidence of enterocutaneous fistula is not elevated despite the presence of contamination. The rate of incisional hernias is significantly reduced after intraperitoneal mesh implantation for postoperative fascial dehiscence or open abdomen.

Incisions do not simply sum

BACKGROUND

Critics of minimally invasive methods sometimes argue that the summed lengths of all trocar sites have a morbidity similar to that for an open incision of equal length. This argument assumes correctly that pain and scarring are proportional to the total tension normal to a linear incision. But the argument also assumes that total tension sums linearly with incision length. This report demonstrates why that premise is not valid.

METHODS

Wounds of various sizes are compared using a simple mathematical model. The closing tension perpendicular to any linear incision is a function of the incision's length, varying symmetrically together with a maximum at the midpoint of length. If tension rises linearly across an incision, integration of the tension relationship demonstrates that the total wound tension actually is proportional to the square of the length. In this report, incisions of various lengths are modeled, and plausible alternative incision scenarios for various procedures (e.g., Nissen, appendectomy) are compared.

RESULTS

Total tension rises nonlinearly with increasing wound length. Thus, total tension across multiple incisions is always less than the total tension for an incision of the same total length. For example, an open appendectomy creates 2.7-fold more wound tension than a laparoscopic appendectomy. Similarly, two 3-mm trocars create less total tension than a single 5-mm trocar.

CONCLUSION

Conventional incisions are subject to more total tension than any combination of trocar incisions of equal total length. This inequality yields three clinically relevant corollaries. First, it supports the practice of using the smallest effective trocars (or even no-trocar methods) to minimize pain and scar. Second, addition of a trocar in difficult cases adds relatively little morbidity. Finally, using two small trocars is better than using a single larger trocar.