Preoperative Botulinum toxin A enabling defect closure and laparoscopic repair of complex ventral hernia

Preoperative botolinum toxin A (BTA) and intraoperative fascial traction (IFT) in the management of complex abdominal wall hernias

INTRODUCTION

Preoperative botolinum toxin A (BTA) administration to the lateral abdominal wall has been widely used since its introduction for treating complex abdominal wall defects and loss of domain (LOD) hernias. Intraoperative fascial traction (IFT) is an established technique for complex abdominal wall hernias exceeding a width of 10 cm and has also shown auspicious results. We present our single center data including 143 consecutive cases combining both techniques from 2019 to 2023. Aim of the study was to develop an algorithm for a tailored approach for very large and complex ventral abdominal wall hernias.

METHODS

Consecutive patients treated with preoperative BTA and IFT from August 2019 to December 2023 were identified in our prospectively maintained database and reviewed retrospectively. Metrics included intraoperative findings and short-term (30 days) postoperative outcomes.

RESULTS

143 patients were included in our retrospective analysis. The mean age was 58.9 years and 99% of all patients had an ASA Score of II or III with a mean body mass index of 32.4 kg/m2. The mean intraoperative reduction of fascia-to-fascia after BTA and IFT was 9.81 cm. 14 patients either had a lateral defect or a combination of a midline and lateral hernia. An additional uni- or bilateral transverse abdominis release (TAR) was necessary in 43 cases (30.1%). The overall surgical site occurrence rate (SSO) was 30.1% of which 13.8% were surgical site infections (SSI). Re-operation and SSO rates were significantly higher if an additional TAR was performed (both p = 0.001; α = 0.05).

CONCLUSIONS

IFT in combination with BTA is a transformative and clinically proven tool in the surgeons' toolbox. It might be an easier, and less invasive alternative to other available techniques in many cases, but it should not be looked at as an ultimate stand-alone method to treat all complex W3 hernias.

[The use of botulinum toxin in hernia surgery: results of a survey in certified hernia centers]

BACKGROUND

Botulinum toxin application into the abdominal wall prior to major hernia repair can reduce the complexity of surgery and has been increasingly used in recent years, even if it is an off-label use.

OBJECTIVE

To what extent is botulinum toxin used in hernia surgery in German-speaking countries and what is the current evidence in the literature?

MATERIAL AND METHODS

In a voluntary online survey of German Society for General and Visceral Surgery (DGAV)-certified competence centers and reference centers for hernia surgery, aspects of botulinum toxin application were surveyed and the results analyzed.

RESULTS

A total of 57 centers took part in the survey, of which 27 (47%) use botulinum toxin. The main reasons for not using it were lack of experience and reimbursement. Of the centers 85% have treated less than 50 patients with botulinum toxin. The main indications were midline hernias (M2-4 according to the EHS classification) with a hernia gap > 10 cm (W3 according to EHS classification) and loss of domain situations. The application was predominantly ultrasound-guided by designated hernia surgeons with 100-200 Allergan or 500 Speywood units 4-6 weeks preoperatively and without complications related to the botulinum toxin application.

CONCLUSION

Botulinum toxin injections in hernia surgery appear to be safe and effective. Ultrasound-guided preoperative bilateral administration is supported by the available data. Specific course and information formats should be offered by the hernia surgery institutions.

The effect of preoperative botulinum toxin a injection on traction force during hernia repair: a prospective, single-blind study, intra-patient comparison using contralateral side as a control

PURPOSE

Ventral hernias are a common complication of laparotomy, posing challenges particularly when primary fascial closure is unattainable. Although chemical component separation using preoperative botulinum toxin A (BTX) injections has emerged as a promising adjunct, objective evidence of its efficacy remains limited. This study aimed to objectively assess the effect of preoperative BTX on traction force during ventral hernia repair.

METHODS

A prospective, single-blind study was conducted on patients with midline incisional hernias following liver transplantation. BTX was administered unilaterally, and the traction force required to medially advance the anterior rectus sheath was measured intraoperatively. Pre- and post-injection CT scans were analyzed for changes in hernia size and LAW muscle measurements. Statistical analyses were performed to evaluate traction force differences between BTX-injected and uninjected sides.

RESULTS

Ten patients underwent hernia repair with primary fascial closure achieved in all cases. Comparison of pre- and post-injection CT scans showed no significant changes in hernia size. LAW muscle length increased by 1.8 cm, while thickness decreased by 0.2 cm. Intraoperative traction force measurements revealed a significant reduction on the BTX-injected side compared to the uninjected side (p < 0.0001). The traction force ratio on the BTX-injected to the uninjected side averaged 57%, indicating the efficacy of BTX in reducing tension.

CONCLUSION

Preoperative BTX significantly reduces traction force during ventral hernia repair, highlighting its potential as an adjunctive therapy in complex cases. While challenges remain in patient selection and outcome assessment, BTX offers a promising avenue for enhancing abdominal wall reconstruction outcomes and reducing surgical complications.

Revisiting large complex ventral hernia repair: multimodal hybrid technique deploying preoperative Botulinum Toxin A injection, laparoscopic anterior components separation and open mesh repair

In the past, various techniques had been described to repair large complex ventral hernias. Laparoscopic technique of components separation showed low complication rates and better overall outcome. Recently, Botulinum Toxin A (BTA) has shown benefit in achieving tension-free repair. We describe here our multimodal technique combining BTA injection, laparoscopic anterior components separation (LACS) and open mesh repair. Ten consecutive cases performed over 3 years were studied. A standardised technique was used with a reasonably short learning curve. Patients who generally fit for general anaesthesia were offered surgery after detailed preoperative imaging work up and informed consent. Demographic details, preoperative risk stratification, intraoperative and postoperative outcomes were recorded and analysed. A structured step by step management strategy was adopted. Total ten (n = 10) cases with median age of 42.5 years (range 28-76 years), male to female ratio of 8:2 and median BMI of 32.6 were included. Three patients had pre-existing stomas. Median diameter of hernial defect was 10 cm, IQR 4.8 cm and range of 6-20 cm. No intraoperative or immediate complications were observed. Median hospital stay was 6 days. Two seromas (20%) and two return to theatre (20%) were observed. One recurrence (10%) was observed after median follow-up of 32 months. No 90-day mortality was recorded. Multimodal technique of BTA injection, LACS and midline mesh repair is a reproducible, safe and effective option to repair large complex ventral hernias.

Achieving fascial closure with preoperative botulinum toxin injections in abdominal wall reconstruction: outcomes from a high-volume center

Preoperative injection of Botulinum Toxin A (Botox) has been described as an adjunctive therapy to facilitate fascial closure of large hernia defects in abdominal wall reconstruction (AWR). The purpose of this study was to evaluate the impact of Botox injections on fascial closure and overall outcomes to further validate its role in AWR. A prospectively maintained database was retrospectively reviewed to identify all patients undergoing AWR at our institution between January 2014 and March 2022. Patients who did and did not receive preoperative Botox injections were analyzed and compared. A total of 426 patients were included (Botox 76, NBotox 350). The Botox group had significantly larger hernia defects (90 cm2 vs 9 cm2, p < 0.01) and a higher rate of component separations performed (60.5% vs 14.4%, p < 0.01). Despite this large difference in hernia defect size, primary fascial closure rates were similar between the groups (p = 0.49). Notably, the Botox group had higher rates of surgical-site infections (SSIs)/surgical-site occurrences (SSOs) (p < 0.01). Following propensity score matching to control for multiple patient factors including age, sex, diabetes, chronic obstructive pulmonary disease (COPD), and hernia size, the Botox group still had a higher rate of component separations (50% vs 26.3%, p = 0.03) and higher incidence of SSIs/SSOs (39.5% vs 13.5%, p = 0.01). Multimodal therapy with Botox injections and component separations can help achieve fascial closure of large defects during AWR. However, adding these combined therapies may increase the occurrence of postoperative SSIs/SSOs.

Area of Focus in 3D Volumetry and Botulinum Toxin A Injection for Giant Diaphragmatic Hernia with Loss of Domain: A Case Report with Video Illustration

Background

Chronic giant diaphragmatic hernia is a severe disease with challenging diagnosis and treatment. Given the risk of loss of domain, the use of botulinum toxin A is an option but has been minimally studied in diaphragmatic hernia surgery.

Case Report

We present a case of a giant diaphragmatic hernia in a 66-years-old patient who showed a 12-year history of progressive chronic respiratory insufficiency. There were not notion of traumatic injuries. The CT-scan showed a giant diaphragmatic hernia with herniation of small bowel, right liver, omentum and transverse colon.

Method

We assessed the risk of loss of domain using a 3D volumetry based on the Sabbagh score and decided to use Botox injection before laparoscopic reduction of the hernia due to the high risk of complications related to the loss of domain. A computed tomography was performed 24 months after surgery and showed no evidence of recurrence. The patient presented an excellent functional result with a normal physical activity.

Conclusion

This report is among the first to highlight the utility of 3D reconstruction in assessing the risk associated with loss of domain and in preparing the abdominal wall with botulinum toxin A for diaphragmatic hernia repair.

A New Ultrasound-Guided, One-Point, Single Interfascial Plane Botulinum Toxin A Injection Technique for the Repair of Ventral Abdominal Wall Hernias Before Surgery: A Case Report

Patients presenting with large ventral abdominal wall hernias require pretreatment with injection botulinum toxin A before surgery. Currently, multipoint and multilayered botulinum injection techniques are practiced. We are describing a new ultrasound-guided, 1-point, single interfascial plane botulinum toxin A injection technique for the closure of big hernial defects.

Use of botulinum toxin type A in the prehabilitation of abdominal wall musculature for hernia repair: a consensus proposal

The prehabilitation of the abdominal wall through the infiltration of botulinum toxin type A, which induces temporary chemical denervation ("chemical component separation") in the lateral abdominal musculature, is a common practice in units specialized in abdominal wall surgery. However, its use for this indication is currently off-label. The main objective of this article is to describe a consensus proposal regarding indications, contraindications, dosages employed, potential side effects, administration method, and measurement of possible outcomes. Additionally, a proposal for an informed consent document endorsed by the Abdominal Wall Section of the Spanish Association of Surgeons is attached.

A Ventral Hernia Management Pathway; A "Getting It Right First Time" approach to Complex Abdominal Wall Reconstruction

INTRODUCTION

Abdominal wall reconstruction (AWR) is an emerging specialty, involving complex multi-stage operations in patients with high medical and surgical risk. At our hospital, we have developed a growing interest in AWR, with a commitment to improving outcomes through a regular complex hernia MDT. An MDT approach to these patients is increasingly recognized as the path forward in management to optimize patients and improve outcomes.

METHODS

We conducted a literature review and combined this with our experiential knowledge of managing these cases to create a pathway for the management of our abdominal wall patients. This was done under the auspices of GIRFT (Getting It Right First Time) as a quality improvement project at our hospital.

RESULTS

We describe, in detail, our current AWR pathway, including the checklists and information documents we use with a stepwise evidence and experience-based approach to identifying the multiple factors associated with good outcomes. We explore the current literature and discuss our best practice pathway.

CONCLUSION

In this emerging specialty, there is limited guidance on the management of these patients. Our pathway, the "Complex Hernia Bundle," currently provides guidance for our abdominal wall team and may well be one that could be adopted/adapted by other centers where challenging hernia cases are undertaken.

Botulinum toxin A in complex incisional hernia repair: a systematic review

PURPOSE

To evaluate the safety, efficacy, and short and long-term postoperative results of using BTA.

METHODS

We conducted a systematic review following the recommendations of the PRISMA method. We systematically reviewed the MEDLINE/PubMed and SCOPUS electronic databases for studies published between January 2010 and September 2021. This systematic review was registered in PROSPERO, with registration number CRD42021252445.

RESULTS

After applying the selection criteria, 11 relevant articles were selected. The total sample size was 1058 patients. Most studies aimed to assess the rate of fascial closure, followed by the rate of recurrence and reporting of postoperative complications, as well as the need for the components separation technique (CST). None of the studies reported serious complications from using BTA. Regarding fascial closure, all articles had rates above 75%, except for one. Surgical site events ranged between 19% and 29.4%. No recurrence in the group that used BTA was recorded in five studies. The other articles reported recurrence rates ranging from 6.4 to 11.4% in the groups that received BTA. The studies had varying follow-up times ranging from 1 to 49 months, with a mean of 18.6 months (± 11.2).

CONCLUSION

This review described most of the key points about the preoperative use of BTA in hernia repair. It can be concluded that the use of BTA is a safe and effective practice that promotes good short and long-term results. However, the limitations of the current literature prevent more accurate conclusions on the subject.

Botulinum Toxin and Progressive Pneumoperitoneum in Loss of Domain Ventral Hernias: A Systematic Review

Introduction: Preoperative progressive pneumoperitoneum (PPP) and botulinum toxin A (BTX) have been used together in the preoperative preparation of patients with loss of domain hernias. This study aims to evaluate the efficacy and safety of the combined use of PPP and BTX. Methods: A systematic electronic search was performed according to the PRISMA criteria. A literature search of scientific articles was conducted up to December 2023. Articles were chosen based on the reference to BTX and PPP in loss of domain ventral hernias with a defect width greater than 10 cm before surgery. The GRADE methodology and the modified Newcastle-Ottawa scale were used to assess the quality of the studies. Results: The research yielded seven articles, with 217 patients analysed in total. BTX was performed 29.5 ± 1.7 days before surgery and PPP was inflated 14.8 ± 5.8 days before surgery. PPP complications were reported in 25.6% of patients, The average reduction of the volume of hernia (VH)/volume of the abdominal cavity (VAC) ratio was 7.6% (range 0.9%-15%). Only 40 patients (18.4%) required a PCS or TAR to repair the loss of domain hernias. The SSI and SSO rates were 17.5% and 26.2%, respectively. No differences in SSI and SSO rates were found between the different repair techniques. The recurrence rate was 5.9% (13/217). Recurrence was significantly higher in patients who underwent IPOM repair than other techniques (p < 0.001). Conclusion: BTX and PPP may be useful tools for the management of loss of domain hernias presenting lower SSI and SSO. The combination of BTX and PPP reduces the use of more invasive repair techniques.

Volumetry after botulinum toxin A: the impact on abdominal wall compliance and endotracheal pressure

PURPOSE

Botulinum toxin type A (BTA) is an adjuvant tool used in the preoperative optimization of complex hernias before abdominal wall reconstruction (AWR). This study aims to investigate changes in the abdominal cavity and hernia sac dimensions after BTA application.

METHOD

A prospective study with 27 patients with a hernia defect of ≥ 10 cm and loss of domain (LOD) ≥ 20% underwent AWR. Computed tomography (CT) measurements and volumetry before and after the application of BTA were performed. Intraoperative and postoperative outcomes were evaluated.

RESULTS

Imaging post-BTA revealed hernia width reduction of 1.9 cm (p = 0.002), lateral abdominal wall muscle elongation of 3.1 cm (p < 0.001), hernia volume reduction (HV) from 2.9 ± 0.9L to 2.4 ± 0.8L (p < 0.001), increase in abdominal cavity volume (ACV) from 9.7 ± 2.5L to 10.3L ± 2.4L (p = 0.003), and a reduction in the HV/ACV ratio from 30.2 ± 5% to 23.4 ± 6% (p < 0.001). Fascial closure was achieved in 92.6% of cases and component separation was required in 78%. The average variation in pulmonary plateau pressure was 3.53 cmH2O, and there were no postoperative respiratory failure recorded. At the 90-day follow-up, the wound morbidity rate was 25%, unplanned readmissions were 11%, and hernia recurrence 7.4%.

CONCLUSION

BTA produces measurable volumetric changes in abdominal wall and appears to facilitate fascial closure. Further studies are required to determine the role of BTA in the surgical armamentarium for complex hernia repair.

The use of botulinum toxin type a to prepare patients with large ventral hernias for laparoscopic hernioplasty: Our experience

OBJECTIVE

Aim: To study the effectiveness of BTA in a total dose of 100 IU as the preparation for patients with primary and incisional ventral hernias (VH).

PATIENTS AND METHODS

Materials and Methods: The prospective study included 59 patients with large VH (defect ³10 cm). All patients received 100 IU of BTA in abdominal wall muscles 4-5 weeks before surgery from June 2017 to December 2022. An average age of the patients was 59.13 ± 9.07 years, body mass index - 32.20 ± 4.95 kg/m2.

RESULTS

Results: An average width of the hernia defect after BTA decreased by 4.5 ± 1.11 cm (p<0.001). An average length of the hernia defect after BTA also decreased, without clinical significance. A significant increase in the length of the abdominal wall and a decrease in its thickness were observed. The abdominal cavity volume after BTA increased by 4.04 ± 4.55% (p=0.008) and the hernial sac volume decreased by 21.43 ± 16.57% (p=0.005). All patients underwent surgery with hernia defect suturing and without component separation: laparoscopic IPOM hernioplasty - 50 (84.7%) patients, open IPOM hernia repair - 7 (11.9%) patients, open sublay hernioplasty - 2 (3.4%) patients. There was no recurrence of hernia during 12 months after surgery.

CONCLUSION

Conclusions: The administration of 100 IU BTA allows to increase the length of the abdominal wall muscles and to perform laparoscopic IPOM hernioplasty for patients with large VH.

Preoperative Abdominal Muscle Elongation Facilitated Laparoscopic Intraperitoneal Onlay Mesh Repair of Complex Ventral Hernia

Background: Complex ventral hernia remains a challenging situation for any surgeon. In this study, our aim was to analyze the effect of laparoscopic intraperitoneal onlay mesh (IPOM) repair in the treatment of complex abdominal wall hernia, with the assistance of preoperative progressive pneumoperitoneum (PPP) and botulinum toxin A (BTA). Methods: In this retrospective study, we included 13 patients with complex ventral hernia between May 2021 and December 2022. All patients undergoing PPP and BTA protocol before hernia repair. The length of abdominal wall muscles and abdominal circumference were measured from CT scan. All hernias were repaired with laparoscopic or laparoscopic-assisted IPOM. Results: Thirteen patients received PPP and BTA injections. PPP and BTA administration time was over 8.8 ± 2.5 days. Before and after PPP and BTA, imaging showed that the length of lateral muscle on each side increased from 14.3 to 17.4 cm (P < .05). The abdominal circumference increased from 81.8 to 87.9 cm (P < .05). Complete fascial closure was obtained in 13 patients (100%), and no patient experienced postoperative abdominal hypertension and ventilatory support. No patient suffered from recurrent hernia to date. Conclusions: Preoperative PPP combined with BTA injection plays a role similar to component separation technique, avoids the abdominal hypertension after laparoscopic IPOM repair of complex ventral hernia.

Systematic review and meta-analysis of the pre-operative application of botulinum toxin for ventral hernia repair

PURPOSE

Surgical repair of large hernia defects requires detailed pre-operative planning, particularly in cases with loss of domain. This situation often hampers mid-line reconstruction, even after component separation, when the size of the hernia is disproportional to the volume of the abdominal area. In this case, other strategies may be needed to place the viscera back into the abdominal cavity after reducing the hernia sac. The administration of botulinum toxin prior to the surgical procedure has been indicated as an adjunct for more complex cases. This results in stretching of the lateral musculature of the abdomen, allowing midline approximation. In addition, the application of botulinum toxin alone has been investigated as a means of downstaging in the management of ventral hernias, thereby precluding component separation and enabling primary closure of the midline by placement of mesh within the retromuscular space using the Rives Stoppa technique.

METHODS

Systematic review of the literature for observational studies involving patients undergoing pre-operative application of botulinum toxin for ventral hernia repair was conducted according to the PRISMA guidelines.

RESULTS

Advance of the lateral musculature of the abdomen by an average of 4.11 cm with low heterogeneity, as well as low rates of surgical site infection (SSI), surgical site occurrences (SSO) and recurrence, was shown.

CONCLUSION

Pre-operative application of botulinum toxin for ventral hernia repair promoted an increase in the length of the lateral musculature of the abdomen which can help improve the outcomes of morbidity and recurrence.

Is there a role for botulinum toxin A in the emergency setting for delayed abdominal wall closure in the management of the open abdomen? A systematic review

INTRODUCTION

Emergency laparotomy for either trauma or non-trauma indications is common and management is varied. Use of the open abdomen technique allowing for planned re-look is an option; however, performing delayed definitive fascial closure (DFC) following this can be a challenge. The use of botulinum toxin-A (BTX) infiltration into the lateral abdominal wall has been well documented within the elective setting; its use within the emergency setting is undecided. This systematic review assesses the efficacy and safety of BTX injection into the lateral abdominal wall muscles in the emergency setting. The primary outcome is DFC rate.

METHODS

Systematic review was performed according to the PROSPERO registered protocol (CRD42020205130). Papers were dual screened for eligibility, and included if they met pre-stated criteria where the primary outcome was DFC. Articles reporting fewer than five cases were excluded. Bias was assessed using the Cochrane Risk of Bias and Joanna Brigg's appraisal tools.

FINDINGS

Fourteen studies were screened for eligibility, twelve full texts were reviewed and two studies were included. Both studies showed evidence of bias due to confounding factors and lack of reporting. Both studies suggested significantly higher rates of DFC than reported in the literature against standard technique (90.7% vs 66%); however, these data are difficult to interpret due to strict study inclusion criteria or lack of a control population.

CONCLUSION

The use of BTX is deemed safe and its effects in the emergency situation may have great potential. Unfortunately, to date, there is insufficient evidence to facilitate opinion.

Building a Center for Abdominal Core Health: The Importance of a Holistic Multidisciplinary Approach

BACKGROUND

This article seeks to be a collection of evidence and experience-based information for health care providers around the country and world looking to build or improve an abdominal core health center. Abdominal core health has proven to be a chronic condition despite advancements in surgical technique, technology, and equipment. The need for a holistic approach has been discussed and thought to be necessary to improve the care of this complex patient population.

METHODS

Literature relevant to the key aspects of building an abdominal core health center was thoroughly reviewed by multiple members of our abdominal core health center. This information was combined with our authors' experiences to gather relevant information for those looking to build or improve a holistic abdominal core health center.

RESULTS

An abundance of publications have been combined with multiple members of our abdominal core health centers members experience's culminating in a wide breadth of information relevant to those looking to build or improve a holistic abdominal core health center.

CONCLUSIONS

Evidence- and experience-based information has been collected to assist those looking to build or grow an abdominal core health center.

Preoperative botulinum A toxin as an adjunct for abdominal wall reconstruction: a single-center early experience at an Academic Center in New York

INTRODUCTION

the botulinum toxin A (BTA) has been used to achieve a chemical component separation, and it has been used with favorable outcomes for the repair of complex ventral hernia (CVH) with and without loss of domain (LD). The aim of this study is to describe our early experience with the chemical component separation in the United Sates.

METHODS

a retrospective observational study of all patients who underwent ventral hernia repair for CVH with or without LD between July 2018 and June 2020. Preoperative BTA was injected in all patients via sonographic guidance bilaterally, between the lateral muscles to achieve chemical denervation before the operation. Patient demographics, anatomical location of the hernia, perioperative data and postoperative data are described.

RESULTS

36 patients underwent this technique before their hernia repair between July 2018 to June 2020. Median age was 62 years (range 30-87). Median preoperative defect size was 12cm (range 6-25) and median intraoperative defect size was 13cm (range 5-27). Median preoperative hernia sac volume (HSV) was 1338cc (128-14040), median preoperative abdominal cavity volume (ACV) was 8784cc (5197-18289) and median volume ration (HSV/ACV) was 14%. The median OR time for BTA administration was 45 minutes (range 28-495). Seroma was the most common postoperative complication in 8 of the patients (22%). Median follow up was 43 days (range 0-580).

CONCLUSION

preoperative chemical component separation with BTA is a safe and effective adjunct to hernia repair in CVH repairs where a challenging midline fascial approximation is anticipated.

Imaging Insights Into Abdominal Wall Function

Purpose

The successful repair of any complex ventral hernia requires a thorough understanding of the underlying anatomical defect and its functional context. We describe an improved “functional” approach to CT imaging of the abdominal wall that can facilitate this understanding and assist surgical planning.

Methods

This invited article reports the observational experience gained from the functional abdominal wall CT examinations of 88 patients who underwent complex ventral hernia repair using pre-operative Botulinum toxin A (BTA) infiltration of the lateral oblique abdominal muscles as well as a further eight patients with diastasis rectus abdominis who were examined to exclude ventral hernia.

Results

The use of a functional CT protocol which supplements resting images with additional “crunching” images (acquired with the abdominal wall muscles all strongly contracted) can significantly improve the demonstration of ventral hernia defects. Crunching acquisitions can also help differentiate true hernias from dysfunctional bulges, identify muscle denervation or atrophic changes, reveal otherwise occult hernias that may be missed on resting or Valsalva images alone, and assist the pre-operative assessment of BTA effect.

Conclusion

A more functional approach to pre-operative CT imaging of the abdominal wall can significantly improve the understanding of complex ventral hernia defects and help formulate effective surgical plans that achieve low recurrence rates and good functional outcomes.

Botulinum Toxin A Facilitated Laparoscopic Repair of Complex Ventral Hernia

Background: Complex ventral hernia repair can be challenging despite the recent advances in surgical techniques. Here, we aimed to examine the effectiveness of preoperative combined use of botulinum toxin A (BTA) and preoperative progressive pneumoperitoneum (PPP) for surgical preparation of patients with complex ventral hernia.

Methods: In this prospective, observational study, we included 22 patients with complex ventral hernia between January 2018 and May 2021. All patients were treated with BTA injections into the lateral abdominal muscles and PPP before hernia repair. The lengths of abdominal wall muscles, the volumes of the incisional hernia (VIH), the volumes of the abdominal cavity (VAC), and the VIH/VAC ratio were measured before and after BTA and PPP using abdominal CT scan. All Hernias were repaired using laparoscopic intra-peritoneal onlay mesh (IPOM) or laparoscopic-open-laparoscopic (LOL) techniques.

Results: Imaging showed a significant increase in the mean lateral abdominal muscle length from 13.1 to 17.2 cm/side (p < 0.01). Before and after BTA and PPP, the mean VIH was 894 cc and 1209 cc (P < 0.01), and the mean VAC was 6,692 cc and 9,183 cc (P < 0.01). The VAC increased by 2,491 cc (P < 0.01) and was greater than the mean VIH before PPP. An average reduction of 0.9% of the VIH/VAC ratio after BTA and PPP was obtained (p > 0.05). All hernias were surgically reduced with mesh, hernia recurrence occurred in only two patients.

Conclusions: The preoperative combined use of PPP and BTA increased the abdominal volume, lengthened the laterally retracted abdominal muscles, and facilitated laparoscopic closure of large complex ventral hernia.

The Use of Botulinum Toxin in Complex Hernia Surgery: Achieving a Sense of Closure

Abdominal wall surgeons have developed a host of tools to help facilitate fascial closure. Botulinum toxin A is one of the most recently identified treatments and has grown in popularity over recent years; showing great promise in a number of case series and cohort studies. The toxin paralyses lateral abdominal wall muscles in order to increase laxity of the tissues—facilitating medialisation of the rectus muscles. Several research groups around the world are developing expertise with its use-uncovering its potential. We present a review of the relevant literature over the last two decades, summarising the key evidence behind its indications, dosing and effects.

Ultrasound-Guided Lateral Abdominal Wall Botulinum Toxin Injection Before Ventral Hernia Repair: A Review for Radiologists

Preoperative ultrasound-guided lateral abdominal wall botulinum toxin injection is a promising method for improving patient outcomes and reducing recurrence rates after ventral hernia repair. A review of the literature demonstrates variability in the procedural technique, without current standardization of protocols. As radiologists may be increasingly asked to perform ultrasound-guided botulinum toxin injections of the lateral abdominal wall, familiarity with the procedure and current literature is necessary.

Seven years of preoperative BTA abdominal wall preparation and the Macquarie system for surgical management of complex ventral hernia

PURPOSE

To assess 7-year outcomes after complex ventral hernia (CVH) repair using pre-operative Botulinum toxin A (BTA) injection and the Macquarie System of management.

METHODS

Clinical examination and functional non-contrast abdominal CT scans were used to assess complications and recurrences encountered in a prospective series of 88 consecutive CVH repairs using pre-operative BTA injection (200 or 300 units) between November 2012 and December 2019. Pre-operative progressive pneumoperitoneum (PPP) and/or component separation (CS) were also used in some cases.

RESULTS

All hernia defects (mean transverse width 12.9 ± 5.2 cm) were successfully closed using either laparoscopic or laparoscopic-assisted open techniques facilitated by pre-operative BTA injection. The mean pre-operative post-BTA lateral oblique length gain was 4.7 ± 2.2 cm/side (p < 0.001). In 43 patients with defects < 12 cm wide, closure was achieved using BTA-only in 33 (76.7%), BTA + PPP in 2 (4.7%), BTA + CS in 5 (11.6%) and BTA + PPP + CS in 3 (7.0%). In the remaining 45 patients with defects [Formula: see text] 12 cm wide, closure was achieved using BTA-only in 9 (20.0%), BTA + PPP in 11 (24.4%), BTA + CS in 5 (11.1%) and BTA + PPP + CS in 20 (44.4%). There was a significant correlation between increasing defect size and the need for 2 or more CVH closure procedures (χ² = 25.28, p < 0.0005). There were no BTA complications. Two patients developed midline hernia recurrences.

CONCLUSION

Pre-operative BTA injection of the abdominal wall is a safe procedure that facilitates hernia defect closure and reduces the need for CS, especially when defect size is less than 12 cm. BTA may also decrease the rate of hernia recurrence.

Effects of Botulinum Toxin A on an Incisional Hernia Reconstruction in a Rat Model

BACKGROUND

Although the effects of botulinum toxin A on hernia reconstruction have been consistently reported, few studies provide objective evidence. The authors aimed to compare the effects of chemical component separation with those of mechanical component separation, and with a combination of chemical and mechanical component separation, in a rat hernia model.

METHODS

Rats were divided into four groups: 1, control; 2, chemical component separation; 3, mechanical component separation; and 4, chemical and mechanical component separation. Four weeks after hernia induction, botulinum toxin A was injected into groups 2 and 4. Hernia repair was performed 2 weeks after chemical component separation when mechanical component separation was performed in groups 3 and 4. Pretreatment and posttreatment defect sizes, traction forces, intraabdominal pressure, and hernia recurrences were analyzed.

RESULTS

The defect size was significantly decreased in groups 2 and 4 after chemical component separation. The traction force was significantly smaller in groups 2 and 3 compared with the control group, and the effects of chemical and mechanical component separation were additive. The mean intraabdominal pressure was 16.83 mmHg in group 1, 10.67 mmHg in group 2, 10.17 mmHg in group 3, and 9.67 mmHg in group 4, thus showing significant reductions following chemical and mechanical component separation. Recurrence was observed in all six animals (100 percent) in groups 1 and 3, but in only one of six (17 percent) in groups 2 and 4.

CONCLUSIONS

Preoperative botulinum toxin A significantly reduces hernia size (by 30 percent) and the traction force required to medialize the rectus abdominis. After hernia repair, chemical component separation decreases the intraabdominal pressure to a similar degree as mechanical component separation, but only chemical component separation appears to reduce hernia recurrence.

Understanding the benefits of botulinum toxin A: retrospective analysis of the Abdominal Core Health Quality Collaborative

This was a retrospective analysis of a prospectively maintained database that objectively evaluated the benefit of preoperative chemical component separation with botulinum toxin A in complex hernia repairs.

Continued evaluation.

Fascial closure in giant ventral hernias after preoperative botulinum toxin a and progressive pneumoperitoneum: A systematic review and meta-analysis

BACKGROUND

The primary objective was to assess the perioperative efficacy of the preoperative use of progressive pneumoperitoneum or Botulinum Toxin A injections in ventral hernia repair.

METHODS

Embase, Medline Ovid, Web of Science, Cochrane Central, and Google Scholar were systematically searched. Studies in English reporting on fascial closure, indications, complications or postoperative outcomes in adult patients that had undergone progressive pneumoperitoneum, Botulinum Toxin A injections, or both before ventral hernia repair were included. Study quality was assessed with the Oxford Levels of Evidence guidelines and the Methodological Index for Non-Randomized Studies criteria. A pooled fascial closure rate and recurrence rate were calculated with random effects models.

RESULTS

Twenty studies were included from the 905 identified, comprising the use progressive pneumoperitoneum (n = 11), Botulinum Toxin A (n = 6), and both techniques (n = 3). The overall fascial closure rate was 0.94 (95% confidence interval 0.89-0.98). Indications for the use of progressive pneumoperitoneum or Botulinum Toxin A were based on objective (eg, computed tomography measurements) or subjective measures (eg, foreseen surgical problems). In contrast to the use of Botulinum Toxin A, reported complications with the use of progressive pneumoperitoneum were ample and sometimes severe. The cumulative reported recurrence rate was 0.03 (95% confidence interval 0.01-0.06).

CONCLUSION

Preoperative progressive pneumoperitoneum and Botulinum Toxin A can facilitate fascial closure without causing significant numbers of adverse events. Botulinum Toxin A qualifies for low-threshold use, yet progressive pneumoperitoneum should be used cautiously owing to a larger number of complications. Definitive recommendations cannot be made as the quality of included studies is low, bias is present, and comparative information is scarce. Registration number Information about the design and conduct of this systematic review has been registered on PROSPERO, registration number CRD42020181679.

Complex ventral hernia repair in a child: An association of botulinum toxin, progressive pneumoperitoneum and negative pressure therapy. A case report on an arising surgical technique

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Giant omphalocele establish a therapeutic challenge to the surgeon - mainly because of the increased visceroabdominal disproportion and underlying malformations - and the best approach is still debatable worldwide.

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This is the second report on the literature and states the management of a child born with giant omphalocele that developed a very complex ventral hernia secondary to an unsuccessful attempt of closing the primary defect.

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It seems that the use of botulinum toxin agents in the abdominal wall is safe and effective in children with giant omphaloceles and it eliminates the use of a mesh even in more difficult cases.

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This technique seems safe and effective and it should be encouraged and best evaluated.

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It is time to start defining better criteria to categorize giant omphalocele in order to choose the best management for each patient.

Introduction

The purpose of this manuscript is to report the management of a child born with giant omphalocele (GO) that developed a complex ventral hernia secondary to an unsuccessful attempt of closing the primary defect.

Presentation of case

The patient underwent a one-step surgery to correct a ventral hernia associated with a largely prolapsed enteroatmospheric fistula (EAF) along with an ileostomy. It was managed by a pre-operative association of botulinum toxin agent (BTA) application with preoperative progressive pneumoperitoneum (PPP) and trans-operative negative pressure wound therapy (NPWT) dressing with staged abdominal closure. The patient needed 4 reoperations due to enteric fistulas. Nine days after the first surgery, it was possible to completely close the abdominal wall without mesh substitution. No signs of hernia in 9 months of follow-up.

Discussion

This is the second report in the literature and it reinforces the safety and effectiveness of the BTA injection associated with PPP in children.

Conclusion

The use of BTA in association with PPP should be encouraged and best investigated in patients with GO. The fistulas were not attributed to the negative pressure. Maybe it is time to start defining better criteria to categorize GO in order to choose the best management for each patient.

Adjunct botox to preoperative progressive pneumoperitoneum for incisional hernia with loss of domain: no additional effect but may improve outcomes

INTRODUCTION

Incisional hernia with loss of domain (IHLD) remains a surgical challenge. Its management requires complex approaches including specific preoperative and intra-operative techniques. This study focuses on the interest of adding preoperative botulinum toxin A (BTA) injection to preoperative progressive pneumoperitoneum (PPP), compared to PPP alone.

MATERIAL

Patients between January 2015 and March 2020 with IHLD who underwent pre-operative preparation were included. Their baseline characteristics were retrospectively analyzed, along with the characteristics of their incisional hernia before and after preparation including CT-scan volumetry. Intra-operative data, early post-operative outcomes, surgical site occurrences (SSOs) including surgical site infection (SSI) were recorded.

RESULTS

Four hundred and fifty (450) patients with incisional hernia were operated, including 41 patients (9.1%) with IHLD, 13 of which had both BTA and PPP, while 28 had PPP only. Both groups were comparable in term of patients and IHLD characteristics. Median increase in the volume of the abdominal cavity (VAbC) was + 55% for the entire population (+ 58.3% for the BTA-PPP group, p < 0.0001 and + 52.8% for the PPP-alone group, p < 0.0001) although the increase in volume was not different between the two groups (p = 0.99). Complete fascial closure was achieved in all patients. SSOs were more frequent in the PPP-alone group than in the BTA-PPP group (17 (60.7%) versus 3 (23.1%) patients, respectively, p = 0.043).

CONCLUSION

BTA and PPP are both useful in pre-operative preparation for IHLD. Combining both significantly increases the volume of abdominal cavity but associating BTA to PPP does not add any volumetric benefit but may decrease the post-operative SSO rate.

Image-guided botulinum toxin injection in the lateral abdominal wall prior to abdominal wall reconstruction surgery: review of techniques and results

Ventral hernias represent the most common complication after abdominal surgery. Loss of domain and/or large ventral hernias in patients are especially challenging for surgeons to manage, but preoperative image-guided botulinum toxin injection has emerged as an effective adjunct to abdominal wall surgery. Loss of domain is caused by chronic muscle retraction of the lateral abdominal wall and leads to an irreducible protrusion of abdominal viscera into the hernia sac. Botulinum toxin can be used in the oblique muscles as a chemical component relaxation technique to aid abdominal wall reconstruction. Intramuscular botulinum toxin injection causes functional denervation by blocking neurotransmitter acetylcholine release resulting in flaccid paralysis and elongation of lateral abdominal wall muscles, increasing the rate of fascial closure during abdominal wall reconstruction, and decreasing recurrence rates. In total, 200-300 units of onabotulinumtoxinA (Botox®) or 500 units of abobotulinumtoxinA (Dypsort®) in a 2:1 dilution with normal saline is most commonly used. Botulinum toxin can be injected with ultrasonographic, EMG, or CT guidance. Injection should be performed at least 2 weeks prior to abdominal wall reconstruction, for maximal effect during surgery. At minimum, botulinum toxin should be injected into the external and internal oblique muscles at three separate sites bilaterally for a total of six injections. Although botulinum toxin use for abdominal wall reconstruction is currently not indicated by the Food and Drug Administration, it is safe with only minor complications reported in literature.

Low-Dose Pre-Operative Botulinum Toxin A Effectively Facilitates Complex Ventral Hernia Repair: A Case Report and Review of the Literature

Background: Complex ventral hernias following laparotomy present a unique challenge in that repair is hindered by the lateral tension of the abdominal wall. A novel approach to overcome this is the “chemical component separation” technique. Here, botulinum toxin A (BTA) is instilled into the muscles of the abdominal wall. This induces flaccid paralysis and effectively reduces tension in the wall, allowing the muscles to be successfully joined in the midline during surgery. We describe a method where a large incisional hernia was repaired using this technique and review the variations in methodology. Case report: A woman in her mid-40s developed a ventral hernia in the setting of a previous laparotomy for a small bowel perforation. Computed tomography (CT) of the abdomen demonstrated an 85 (Width) × 95 mm (Length) ventral hernia containing loops of the bowel. Pre-operative botulinum toxin A administration was arranged at the local interventional radiology department. A total of 100 units of BTA were instilled at four sites into the muscular layers of the abdominal wall under CT-fluoroscopic guidance. She underwent an open incisional hernia repair 4 weeks later, where the contents were reduced and the abdominal wall layers were successfully joined in the midline. There was no clinical evidence of hernia recurrence at 3-months follow-up. Conclusion: Low-dose BTA effectively facilitates the surgical management of large ventral incisional hernias. There is, however, significant variation in the dosage, concentration and anatomical landmarks in which BTA is administered as described in the literature. Further studies are needed to assess and optimise these variables.

Ultrasound-Guided Chemical Component Separation with Botulinum Toxin A prior to Surgical Hernia Repair

US-guided chemical component separation (CCS) of the abdominal musculature using botulinum toxin A can facilitate the surgical repair of large or complex hernias. Eight patients (2 women and 6 men with median age of 54 years [range, 34-78 years]) underwent preoperative US-guided CCS with hydrodissection before planned surgical repair of large or complex ventral (n = 4), inguinal (n = 2), and flank (n = 2) hernias by 2 interventional radiologists. Technical success rate of US-guided CCS procedures was 100%, and all patients achieved surgical closure a mean 34.1 days (range, 14-48 days) after US-guided CCS.

Botulinum toxin abdominal wall injection and post-omphalocele ventral hernia repair: database and proposal of a protocol

Background

Post-omphalocele ventral hernias (POVH) are common after giant omphaloceles. Abdominal wall botulinum toxin injections (BTI) are useful to treat complex incisional hernias (CIH) in adults, which may also apply to POVH. We review BTI data in the treatment of CIH and POVH and propose an algorithm applicable to POVH.

Results

Sixteen papers which described the treatment of CIH on the treatment of POVH in adults (n = 15) and children (n = 1) were reviewed. BTI elongates the lateral abdominal wall and reduces the hernia defect, with a lower incidence of compartment syndrome and respiratory complications. Doses and injection volumes vary. Effects start after 3 days, peak after 10–15 days, stabilize for 2–3 months, and decline after 4–6 months, disappearing after 6–9 months. Patients should be operated on 3–4 weeks after injection. Post-operative complications are uncommon. BTI may be associated with pre-operative pneumoperitoneum (PPP). Children presenting POVH differ from adults presenting CIH. Associated congenital cardiac malformations, genetically determined syndromes, pulmonary hypoplasia, abdominal wall hypoplasia, and thoracic dysmorphism, are common; children need sedation for any procedures; non-absorbable reinforcing meshes are not indicated; and POVH limits are frequently near to the costal margin.

Conclusion

BTI to induce preoperative muscular relaxation in preparation of CIH repair in adults is effective and safe. Experience with the method in children with POVH is limited, but the proposal is logical and probably safe. POVH differs from CIH in some aspects, especially abdominal wall hypoplasia, proximity to the rib cage, and diaphragmatic biomechanics.

Intraoperative Botulinum Toxin Chemodenervation and Analgesia in Abdominal Wall Reconstruction

Purpose. To analyze the impact of botulinum toxin chemodenervation on postoperative opiate consumption through a novel intraoperative injection protocol. Methods. A retrospective review of the implementation of a novel intraoperative botulinum toxin injection into both rectus and oblique musculature. Patients undergoing open retrorectus release, with and without intraoperative chemodenervation with Botox, were retrospectively collected between 2015 and 2019. Demographics, comorbidities, and opioid use in morphine milligram equivalents (MMEs) were retrospectively captured. Basic descriptive statistics and linear regression analysis were performed. Results. 19 patients in the Botox and 22 in the no Botox group were analyzed. Basic demographics were similar with female preponderance in the Botox group, 58% vs 27%, P = .05. Median hernia length was 15 cm for both groups (P = .57), median hernia width was 8 vs 9 cm (P = .39), epidural catheter used in 0 vs 4 (P = .11), transverse abdominal plane blocks in 3 vs 4 (P = 1), median MME usage was 191 vs 230 (P = .37) in the inpatient setting, 225 vs 300 (P = .17) in the outpatient setting, and 405 vs 568 (P = .07) in total for Botox vs no Botox groups. Stepwise linear regression analysis identified Botox as the only predictor for MME usage, P = .048. Conclusions. Chemodenervation was the only factor associated with reduced opioid usage compared to a standard group using multimodality analgesia. The role of muscular pain in laparotomy is likely underappreciated and understudied. Intraoperative selective muscular chemodenervation may play a significant role in recovery from abdominal surgery and requires further study.

[Minimally invasive correction of anatomical features of anterior abdominal wall and ventral hernias]

Conventional «open» procedures for ventral hernias and diastasis recti are widely known, used everywhere and have a great number of author's improvements related to surgeon's experience, availability of modern information, equipment and materials. K. LeBlanc and W. Booth (1993) reported IPOM-method with non-adhesive coating that is considered a milestone in surgery of anterior abdominal wall and ventral hernia. This technique has gained recognition among surgeons around the world due to its technical simplicity, minimal invasiveness and high reproducibility. However, certain disadvantages of this technique have been shown over the past time that justified advisability of searching for another methods of anterior abdominal wall reinforcement. Thus, E-Milos, LIRA, TESAR, eTEP, REPA, TARM, TARUP techniques are currently available. This review is devoted to technical features of these techniques, their potential advantages and disadvantages.

Implementing preoperative Botulinum toxin A and progressive pneumoperitoneum through the use of an algorithm in giant ventral hernia repair

BACKGROUND

Repair of large ventral hernias with loss of domain can be facilitated by preoperative Botulinum toxin A (BTA) injections and preoperative progressive pneumoperitoneum (PPP). The aim of this study is to evaluate the outcomes of ventral hernioplasty using a standardized algorithm, including component separation techniques, preoperative BTA and PPP.

METHODS

All patients between June 2014 and August 2018 with giant hernias (either primary or incisional) of more than 12 cm width were treated according to a previously developed standardized algorithm. Retrospective data analysis from a prospectively collected dataset was performed. The primary outcome was closure of the anterior fascia. Secondary outcomes included complications related to the preoperative treatment, postoperative complications, and recurrences.

RESULTS

Twenty-three patients were included. Median age was 65 years (range 28-77) and median BMI was 31.4 (range 22.7-38.0 kg/m²). The median loss of domain was 29% (range 12-226%). For the primary and secondary endpoints, 22 patients were analyzed. Primary closure of the anterior fascia was possible in 82% of all patients. After a median follow-up of 19.5 months (range 10-60 months), 3 patients (14%) developed a hernia recurrence and 16 patients (73%) developed 23 surgical site occurrences, most of which were surgical site infections (54.5%).

CONCLUSION

Our algorithm using both anterior or posterior component separation, together with preoperative BTA injections and PPP, achieved an acceptable fascial closure rate. Further studies are needed to explore the individual potential of BTA injections and PPP, and to research whether these methods can prevent the need for component separation, as postoperative wound morbidity remains high in our study.

Preoperative Ultrasound-Guided Botulinum Toxin A Injection Facilitates Closure of a Complex Abdominal Wall Hernia: A Case Report

Complex abdominal wall hernia repairs can have high failure rates. Many surgical techniques have been proposed with variable success. We report our experience with a new collaborative protocol between general surgery and regional anesthesiology and acute pain medicine services to provide preoperative botulinum toxin A injections to a patient with a large complex ventral hernia to facilitate primary closure. Toxin was administered into the 3 abdominal wall muscle layers under ultrasound guidance at multiple sites 2 weeks before surgery. The resulting flaccid paralysis of the abdominal musculature facilitated a successful primary surgical closure with no postoperative complications.

Ventral hernia secondary to giant omphalocele in a child: combined approach of botulinum toxin and preoperative progressive pneumoperitoneum

Omphalocele is a congenital abdominal wall defect that occurs approximately 1 in 4000-6000 live births. The abdominal-visceral disproportion, large diameter of the defect, volume of liver in the sac along with high incidence of associated anomalies make the surgical management a real challenge. Currently, there are two strategies for managing giant omphaloceles, staged surgical closure and nonoperative delayed closure. The combined treatment with PPP and BoNT/A injection has recently been described in adults. There is strong evidence on safety and efficacy of the use of BoNT/As in other areas of pediatrics and no recent reports of PPP use in children. Also, there are no data available about the combination of both techniques in pediatric population. The purpose of this manuscript is to report a case of a 7-year-old female child that was referred to our institution with a large ventral hernia secondary to omphalocele. We opted for a combined approach with BoNT/A injection and PPP before the definitive surgery. The surgical result was great with midline closure with no tension and no need for prosthetic substitution or component separation needed. To our knowledge, this is the first case report of BoNT/A injection and PPP for large ventral hernias in children. BoNT/A application was safe and the PPP technique was also proved to be applicable on children. We believe that the combination of BoNT/A and PPP presented to be a safe approach with an excellent result, particularly for not needing abdominal wall prosthetic substitution.

Short-term safety of preoperative administration of botulinum toxin A for the treatment of large ventral hernia with loss of domain

PURPOSE

Preoperative intramuscular-administered botulinum toxin A (BTA) in the lateral abdominal muscles prior to abdominal wall reconstruction has been reported to produce a flaccid paralysis and improve the primary closure rate of large ventral hernias with loss of domain. Complications to this treatment remain sparsely described. The aim of the current study was to report safety and short-term outcome of abdominal wall reconstruction aided by BTA administration.

METHODS

This was a retrospective two-center study including all patients undergoing abdominal wall reconstruction for ventral hernia aided by preoperative BTA administration to the lateral abdominal muscles. Data were retrieved from patient charts and included preoperative demographic and perioperative information as well as postoperative 30-day complications and readmissions.

RESULTS

A total of 37 patients underwent BTA administration prior to hernia repair. The mean age and body mass index were 59.5 (SD 10.1) years and 31.1 (SD 5.2) kg/m². The BTA injections were administered mean 31.6 days (SD 10.0) prior to the hernia repair. One (2.7%) patient reported pain as a complication immediately after the BTA administration. Subsequent to the hernia repair, six (16.2%) patients were readmitted within 30 days. Nine patients (24.3%) had wound complications and medical complications occurred in seven (18.9%) patients.

CONCLUSIONS

We found early preoperative administration of BTA a safe adjunct to large ventral hernia repair, without adverse events related to the administration preoperative. Future studies should further highlight the efficacy of preoperative BTA for reconstruction of otherwise untreatable hernias.

Limitations of Electromyography in the Assessment of Abdominal Wall Muscle Contractility Following Botulinum Toxin A Injection

Purpose: Pre-operative botulinum toxin A (BTA) injection of the lateral obliques aims to facilitate the closure of large ventral hernia defects and decrease the risk of repair breakdown during the critical healing phase. The exact duration of post-operative BTA effect and top-up timing in cases at high risk of recurrence remains uncertain. This study was designed to assess the value of electromyography (EMG) in determining the appropriate time for BTA top-up. Methods: 56 patients underwent ventral hernia repair with pre-operative BTA infiltration of the lateral obliques. Eleven patients at high risk of recurrence considered suitable for BTA top-up were assessed post-operatively with both functional computed tomography (CT) and EMG. CT assessed segmental contractility of each muscle layer. Single-point EMG assessed the activity of individual muscle layers bilaterally in the anterior axillary line. Results: CT showed (i) variable contractility of anterior and posterior muscle segments prior to BTA injection; (ii) absent or incomplete muscle paralysis in over half of all segments; (iii) increased BTA effect on progress scans; and (iv) non-uniform pattern of change in BTA effect between the anterior and posterior muscle. EMG demonstrated modest voluntary activity in most muscle layers. Compared to standard of reference (CT), EMG showed moderate sensitivity (0.62), poor specificity (0.48), poor accuracy (0.57), and incorrect grading in 71% of true positive results. Conclusions: As BTA effect wanes, single-point EMG cannot reliably determine functional muscle status. A novel finding is that BTA-induced paralysis of the abdominal muscles may be remarkably non-uniform in degree, distribution and duration.