Interrupted or continuous slowly absorbable sutures - design of a multi-centre randomised trial to evaluate abdominal closure techniques INSECT-trial [ISRCTN24023541]

Superiority trial for the development of an ideal method for the closure of midline abdominal wall incisions to reduce the incidence of wound complications after elective gastroenterological surgery: study protocol for a randomized controlled trial

BACKGROUND

The recent guidelines from the European and American Hernia Societies recommend a continuous small-bite suturing technique with slowly absorbable sutures for fascial closure of midline abdominal wall incisions to reduce the incidence of wound complications, especially for incisional hernia. However, this is based on low-certainty evidence. We could not find any recommendations for skin closure. The wound closure technique is an important determinant of the risk of wound complications, and a comprehensive approach to prevent wound complications should be developed.

METHODS

We propose a single-institute, prospective, randomized, blinded-endpoint trial to assess the superiority of the combination of continuous suturing of the fascia without peritoneal closure and continuous suturing of the subcuticular tissue (study group) over that of interrupted suturing of the fascia together with the peritoneum and interrupted suturing of the subcuticular tissue (control group) for reducing the incidence of midline abdominal wall incision wound complications after elective gastroenterological surgery with a clean-contaminated wound. Permuted-block randomization with an allocation ratio of 1:1 and blocking will be used. We hypothesize that the study group will show a 50% reduction in the incidence of wound complications. The target number of cases is set at 284. The primary outcome is the incidence of wound complications, including incisional surgical site infection, hemorrhage, seroma, wound dehiscence within 30 days after surgery, and incisional hernia at approximately 1 year after surgery.

DISCUSSION

This trial will provide initial evidence on the ideal combination of fascial and skin closure for midline abdominal wall incision to reduce the incidence of overall postoperative wound complications after gastroenterological surgery with a clean-contaminated wound. This trial is expected to generate high-quality evidence that supports the current guidelines for the closure of abdominal wall incisions from the European and American Hernia Societies and to contribute to their next updates.

TRIAL REGISTRATION

UMIN-CTR UMIN000048442. Registered on 1 August 2022. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055205.

Abdominal fascia closure following elective midline laparotomy: a surgical experience at a tertiary care hospital in Tanzania

Background

The optimal strategy of abdominal wall closure after midline laparotomy has remained an issue of ongoing debate. This study was undertaken to describe our own experiences with abdominal fascial closure following elective midline laparotomy and compare with what is described in literature.

Methods

This was a descriptive prospective study of patients who underwent elective midline laparotomy at Bugando Medical Centre between March 2009 and February 2014.

Results

A total of 872 patients (M:F = 2.8:1) were studied. The median age was 38 years. The fascia closure was performed with a continuous and interrupted sutures in 804 (92.2%) and 68 (7.8%) patients, respectively. Mass closure and layered closure were performed in 842 (96.6%) and 30 (3.4%) patients, respectively. Monofilament sutures were applied for fascia closure in 366 (42.0%) patients, multifilament sutures in 506 (58.0%) patients. Non-absorbable sutures were chosen in 304 (34.9%) patients, slowly absorbable sutures in 506 (58.0%), and moderately absorbable sutures in 62 (7.1%) patients. Sutures used for fascial closure were vicryl 464 (53.2%), nylon 250 (28.7%), prolene 62 (7.1%), PDSII 54 (6.2%) and silk 42 (4.8%). Sutures with the strength of 0 were used in 214 (24.4%) patients, with strength of 1 in 524 (60.1%) patients, and with strength of 2 in 134 (15.4%) patients. The mean time required for massive closure of the midline incision was 8.20 ± 6.12 min whereas in layered closure, the mean time required for closure was 12.22 ± 7.11 min and this was statistically significant (p = 0.002). Mass closure was significantly associated with low incidence of wound dehiscence and incisional hernia (p < 0.001). Continuous suture was significantly associated with low incidence of wound dehiscence and incisional hernia as compared to interrupted suture (p < 0.001). Non-absorbable sutures were significantly associated with increased incidence of persistent wound pain and stitch sinus as compared to absorbable sutures (p < 0.001). The use of monofilament sutures was insignificantly associated with low incidence of surgical site infection as compared to multifilament sutures (p = 0.051). Prolene was significantly associated with persistent wound pain as compared to vicryl (p = 0.017).

Conclusion

Continuous mass closure with vicryl is commonly used for abdominal fascial closure following elective midline laparotomy in our setting and gives satisfactory results.

Continuous versus interrupted skin sutures for non-obstetric surgery

BACKGROUND

Most surgical procedures involve a cut in the skin, allowing the surgeon to gain access to the surgical site. Most surgical wounds are closed fully at the end of the procedure; this review focuses on these closed wounds. There are many ways to close the surgical incision, for example, using sutures (stitches), staples, tissue adhesives or tapes. Skin sutures can be continuous or interrupted. In general, continuous sutures are usually subcuticular and can be absorbable or non-absorbable, while interrupted sutures are usually non-absorbable and involve the full thickness of the skin - although some surgeons do use absorbable interrupted sutures.

OBJECTIVES

To compare the benefits and harms of continuous compared with interrupted skin closure techniques in participants undergoing non-obstetric surgery.

SEARCH METHODS

In August 2013 we searched the following databases: Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid Embase; and EBSCO CINAHL.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) that compared skin closure using continuous sutures with skin closure using interrupted sutures, irrespective of whether there were differences in the nature of the suture materials used in the two groups. We included all relevant RCTs in the analysis, irrespective of language of publication, publication status, publication year or sample size.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified the trials and extracted data. We calculated the risk ratio (RR) with 95% confidence intervals (CI) for comparing binary outcomes between the groups, and calculated the mean difference (MD) with 95% CI for comparing continuous outcomes. We performed meta-analysis using a fixed-effect model and a random-effects model. We performed intention-to-treat analysis whenever possible.

MAIN RESULTS

We included five RCTs with a total of 827 participants. Outcomes were available for 730 participants (384 participants randomised to continuous sutures and 346 participants to interrupted sutures). All the trials were of unclear or high risk of bias. The participants underwent abdominal or groin operations. The only outcomes reported in the trials were superficial surgical site infection, superficial wound dehiscence (breakdown) and length of hospital stay. Other important outcomes such as quality of life, long-term patient outcomes and use of healthcare resources were not reported in these trials.Overall, 6.5% (39/602 participants, four trials) developed superficial surgical site infections. There was no significant difference between the groups in the proportion of participants who developed superficial surgical site infections (RR 0.73; 95% CI 0.40 to 1.33). A total of 23 participants (23/625 (3.7%), four trials) developed superficial wound dehiscence. Twenty-two of the 23 participants belonged to the interrupted suture group.The proportion of participants who developed superficial wound dehiscence was statistically significantly lower in the continuous suture group compared to the interrupted suture group (RR 0.08; 95% CI 0.02 to 0.35). Most of these wound dehiscences were reported in two recent trials in which the continuous skin suture groups received absorbable subcuticular sutures while the interrupted skin suture groups received non-absorbable transcutaneous sutures. The non-absorbable sutures were removed seven to nine days after surgery in the interrupted sutures groups whilst sutures in the comparator groups were not removed, being absorbable. The continuous suture technique with absorbable suture does not require suture removal and provides support for the wound for a longer period of time. This may have contributed to the difference between the two groups in the proportion of participants who developed superficial wound dehiscence. There was no significant difference in the length of the hospital stay between the two groups (MD -1.40 days; 95% CI -7.14 to 4.34).

AUTHORS' CONCLUSIONS

Superficial wound dehiscence may be reduced by using continuous subcuticular sutures. However, there is uncertainty about this because of the quality of the evidence. Besides, the nature of the suture material used may have led to this observation, as the continuous suturing technique used suture material that did not need to be removed, whereas the comparator used interrupted (non-absorbable) sutures that did need to be removed. Differences in the methods of skin closure have the potential to affect patient outcomes and use of healthcare resources. Further well-designed trials at low risk of bias are necessary to determine which type of suturing is better.

Evaluation of the safety and efficacy of MonoMax® suture material for abdominal wall closure after primary midline laparotomy-a controlled prospective multicentre trial: ISSAAC [NCT005725079]

Purpose

Different suture techniques and various suture materials are in use to close midline incisions after primary laparotomy. The ISSAAC study aimed to assess the safety and efficacy of the new ultra-long-term absorbable, elastic monofilament suture material MonoMax® for abdominal wall closure.

Methods

This is a single-arm, multicentre prospective study that included 150 patients undergoing a primary elective midline incision. The control group consists of 141 patients from the INSECT study who received MonoPlus® or PDS® for abdominal wall closure. The incidences of burst abdomen and wound infection until the day of discharge were defined as the primary composite endpoints. The rate of incisional hernias 1 year after surgery, the length of postoperative hospital stay and safety parameters served as secondary endpoints. The study has been registered under www.clinicaltrials.gov [NCT005725079].

Results

Eleven patients in the ISSAAC study [7.3%; 95% CI = (3.9; 13.1%)] experienced wound infection or burst abdomen until the day of discharge as compared to 16 [11.3%; 95% CI = (6.6; 17.8%)] patients in the INSECT control group (p = 0.31). The length of postoperative hospital stay was comparable in both study groups. One year after surgery, incisional hernias were observed in 21 ISSAAC patients (14.0%) in contrast to 30 hernias (21.3%) in the INSECT control group.

Conclusions

The ultra-long-term absorbable, elastic monofilament suture material MonoMax® is safe and efficient for abdominal wall closure.

A prospective, randomised, controlled, double-blind phase I-II clinical trial on the safety of A-Part Gel as adhesion prophylaxis after major abdominal surgery versus non-treated group

Background

Postoperative adhesions occur when fibrous strands of internal scar tissue bind anatomical structures to one another. The most common cause of intra-abdominal adhesions is previous intra-abdominal surgical intervention. Up to 74% of intestinal obstructions are caused by post surgical adhesions. Although a variety of methods and agents have been investigated to prevent post surgical adhesions, the problem of peritoneal adhesions remains largely unsolved. Materials serving as an adhesion barrier are much needed.

Methods/Design

This is a prospective, randomised, controlled, patient blinded and observer blinded, single centre phase I-II trial, which evaluates the safety of A-Part^® Gel as an adhesion prophylaxis after major abdominal wall surgery, in comparison to an untreated control group. 60 patients undergoing an elective median laparotomy without prior abdominal surgery are randomly allocated into two groups of a 1:1- ratio. Safety parameter and primary endpoint of the study is the occurrence of wound healing impairment or peritonitis within 28 (+10) days after surgery. The frequency of anastomotic leakage within 28 days after operation, occurrence of adverse and serious adverse events during hospital stay up to 3 months and the rate of adhesions along the scar within 3 months are defined as secondary endpoints. After hospital discharge the investigator will examine the enrolled patients at 28 (+10) days and 3 months (±14 days) after surgery.

Discussion

This trial aims to assess, whether the intra-peritoneal application of A-Part^® Gel is safe and efficacious in the prevention of post-surgical adhesions after median laparotomy, in comparison to untreated controls.

Trial registration

NCT00646412

Current practice of abdominal wall closure in elective surgery - Is there any consensus?

BACKGROUND

Development of incisional hernia after open abdominal surgery remains a major cause of post-operative morbidity. The aim of this study was to determine the current practice of surgeons in terms of access to and closure of the abdominal cavity in elective open surgery.

METHODS

Twelve surgical departments of the INSECT-Trial group documented the following variables for 50 consecutive patients undergoing abdominal surgery: fascial closure techniques, applied suture materials, application of subcutaneous sutures, subcutaneous drains, methods for skin closure. Descriptive analysis was performed and consensus of treatment variables was categorized into four levels: Strong consensus >95%, consensus 75-95%, overall agreement 50-75%, no consensus <50%.

RESULTS

157 out of 599 patients were eligible for analysis (85 (54%) midline, 54 (35%) transverse incisions). After midline incisions the fascia was closed continuously in 55 patients (65%), using slowly absorbable (n = 47, 55%), braided (n = 32, 38%) sutures with a strength of 1 (n = 48, 57%). In the transverse setting the fascia was closed continuously in 39 patients (72%) with slowly absorbable (n = 22, 41%) braided sutures (n = 27, 50%) with a strength of 1 (n = 30, 56%).

CONCLUSION

In the present evaluation midline incision was the most frequently applied access in elective open abdominal surgery. None of the treatments for abdominal wall closure (except skin closure in the midline group) is performed on a consensus level.

Primary mesh augmentation with fibrin glue for abdominal wall closure--investigations on a biomechanical model

BACKGROUND

The occurrence of incisional hernias after various types of abdominal procedures and incisions continues to be a problem. A number of studies conducted for diverse risk groups have identified a beneficial role for the prophylactic use of mesh augmentation. To what extent this affects the stability of a suture was tested in our biomechanical model.

MATERIALS AND METHODS

To that effect, we compared three groups, carrying out six measurements in each case: (1) single suture in a muscle specimen, (2) suture and additional reinforcement with fibrin glue, and (3) suture and additional reinforcement with a mesh fixed with fibrin glue (Tissucol, Tisseel; with an overlap of 2 cm to all sides).

RESULTS

The single suture conferred a tensile strength, which in our model, was just above the prescribed maximum abdominal pressure of 32 N (37.3 N). The additional use of fibrin glue did not have any significant impact on this result (41.8 N). Only through mesh augmentation with fibrin glue was it possible to achieve a significantly greater tensile strength (64.5 N, p = 0.003).

CONCLUSIONS

The prophylactic use of meshes for stabilization of laparotomy closures appears to be effective. Adequate mesh fixation can be achieved with fibrin glue alone. Further experimental studies and in particular randomized clinical trials are needed to demonstrate proof of the long-term advantages of mesh augmentation in risk groups.

A historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety and efficacy of MonoMax suture material for abdominal wall closure after primary midline laparotomy. ISSAAC-Trial [NCT005725079]

BACKGROUND

Several randomized controlled trials have compared different suture materials and techniques for abdominal wall closure with respect to the incidence of incisional hernias after midline laparotomy and shown that it remains, irrespective of the methods used, considerably high, ranging from 9% to 20%. The development of improved suture materials which would reduce postoperative complications may help to lower its frequency.

DESIGN

This is a historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety of MonoMax suture material for abdominal wall closure in 150 patients with primary elective midline incisions. INSECT patients who underwent abdominal closure using Monoplus and PDS will serve as historical control group. The incidences of wound infections and of burst abdomen are defined as composite primary endpoints. Secondary endpoints are the frequency of incisional hernias within one year after operation and safety. To ensure adequate comparability in surgical performance and recruitment, the 4 largest centres of the INSECT-Trial will participate. After hospital discharge, the investigators will examine the enrolled patients again at 30 days and at 12 +/- 1 months after surgery.

CONCLUSION

This historically controlled, single-arm, multi-centre, prospective ISSAAC trial aims to assess whether the use of an ultra-long-lasting absorbable monofilament suture material is safe and efficient.

TRIAL REGISTRATION

NCT005725079.

A concept for trial institutions focussing on randomised controlled trials in surgery

Background

Although considered the reference standard for generating valid scientific evidence of a treatment's benefits and harms, the number of Randomised Controlled Trials (RCT) comparing surgical techniques remains low. Much effort has been made in order to overcome methodological issues and improve quality of RCTs in surgery. To the present there has been, however, only little emphasis on development and maintenance of institutions for implementation of adequately designed and conducted surgical RCTs.

Mehods/Design

Description of the developments in surgical RCT infrastructure in Germany between 2001 and 2006. Cross sectional evaluation of completed and ongoing surgical RCTs within the German Surgical Society and the Clinical Study Centre, Department of Surgery, University of Heidelberg.

Results

Foundation of a national Clinical Trial Centre (CTC) for the organisation of multi-centre RCTs in the surgical setting (Study Center of the German Surgical Society, SDGC). Establishment of a network of CTCs with affiliated Clinical Sites (CSs) to enhance patient recruitment and shorten the duration of RCTs. Since its foundation four surgical RCTs with a total sample size of 1650 patients (1006 of these randomised) have been supervised by the SDGC with 35 CSs involved in patient recruitment. Five further CTCs were set up in 2006. Together with their affiliated CSs a network has been organised providing improved conditions for the conduction of surgical RCTs.

Conclusion

Improvement of infrastructure substantially facilitates integration of RCTs into routine surgical practice. A network of collaborating CTCs and CSs can provide an adequate infrastructure for the conduction of multi-centre RCTs.

Assessment of the ethical review process for non-pharmacological multicentre studies in Germany on the basis of a randomised surgical trial

OBJECTIVE

To examine the current ethical review process (ERP) of ethics committees in a non-pharmacological trial from the perspective of a clinical investigator.

DESIGN

Prospective collection of data at the Study Centre of the German Surgical Society on the duration, costs and administrative effort of the ERP of a randomised controlled multicentre surgical INSECT Trial (INterrupted or continuous Slowly absorbable sutures-Evaluation of abdominal Closure Techniques Trial, ISRCTN 24023541) between November 2003 and May 2005.

SETTING

Germany.

PARTICIPANTS

18 ethics committees, including the ethics committee handling the primary approval, responsible overall for 32 clinical sites throughout Germany. 8 ethics committees were located at university medical schools (MSU) and 10 at medical chambers. Duration was measured as days between submission and receipt of final approval, costs in euros and administrative effort by calculation of the product of the total number of different types of documents and the mean number of copies required (primary approval acting as the reference standard).

RESULTS

The duration of the ERP ranged from 1 to 176 (median 31) days. The median duration was 26 days at MSUs compared with 34 days at medical chambers. The total cost was euro2947. 1 of 8 ethics committees at universities (euro250) and 8 of 10 at medical chambers charged a median fee of euro162 (mean euro269.70). The administrative effort for primary approval was 30. Four ethics committees required a higher administrative effort for secondary approval (37, 39, 42 and 104).

CONCLUSION

The ERP for non-pharmacological multicentre trials in Germany needs improvement. The administrative process has to be standardised: the application forms and the number and content of the documents required should be identical or at least similar. The fees charged vary considerably and are obviously too high for committees located at medical chambers. However, the duration of the ERP was, with some exceptions, excellent. A centralised ethics committee in Germany for multicentre trials such as the INSECT Trial can simplify the ERP for clinical investigators in and outside the country.

Totally laparoscopic versus conventional ileoanal pouch procedure--design of a single-centre, expertise based randomised controlled trial to compare the laparoscopic and conventional surgical approach in patients undergoing primary elective restorative proctocolectomy--LapConPouch-Trial

BACKGROUND

Restorative proctocolectomy is increasingly being performed minimal invasively but a totally laparoscopic technique has not yet been compared to the standard open technique in a randomized study.

METHODS/DESIGN

This is a two armed, single centre, expertise based, preoperatively randomized, patient blinded study. It is designed as a two-group parallel superiority study. Power calculation revealed 80 patients per group in order to recruit the 65 patients to be analysed for the primary endpoint. The primary objective is to investigate intra-operative blood loss and the need for blood transfusions. We hypothesise that intra-operative blood loss and the need for peri-operative blood transfusions are significantly higher in the conventional group. Additionally a set of surgical and non-surgical parameters related to the operation will be analysed as secondary objectives. These will include operative time, complications, postoperative pain, lung function, postoperative length of hospital stay, a cosmetic score and pre-and postoperative quality of life.

DISCUSSION

The trial will answer the question whether there is indeed an advantage in the laparoscopic group in regard to blood loss and the need for blood transfusions. Moreover, it will generate data on the safety and potential advantages and disadvantages of the minimally invasive approach.

Projektauswahl und Protokollerstellung im Studienzentrum der Deutschen Gesellschaft für Chirurgie

BACKGROUND

The Study Centre of the German Surgical Society (SDGC) designs, conducts, and analyses multicentre randomised controlled surgical trials. The aim of this paper is to present the decision-making process and responsibilities of the SDGC from submission of a study idea to full protocol development in order to achieve transparency in trial selection.

METHODS

The process is divided into four steps. Study ideas can be submitted electronically by members of the German Surgical Society using a form via the homepage of the institution. Firstly, ideas are screened by staff members within 4 weeks for methodological and clinical relevance. Feasible and novel ideas are then converted to trial outlines in cooperation with the submitting surgeon. As a third step, the Steering Committee of the SDGC decides whether to accept the project using a list of defined criteria. Finally, the SDGC draws up a full protocol together with the submitting surgeon. All ideas and decisions are accessible via the SDGC homepage.

CONCLUSIONS

The process described should help in the selection of relevant projects, acquisition of grants, and maintenance of transparency in trial selection and the protocol development process.

Chirurgische Durchtrennung und Verschluss der Bauchdecke

Access to the abdominal cavity must be performed in such a way that surgical treatment procedures can be performed safely. For skin incision, scalpel and electrocautery are equivalent. Subcutaneous tissue and fascias must be divided by electrocautery to minimize blood loss. The best way to close the abdominal cavity is by an all layer, slowly absorbable, running suture with a suture: wound length ratio of at least 4:1. Closing the peritoneal layer is not necessary. Subcutaneous sutures and drains do not reduce the risk of wound complications. Staples should be used for closing the skin.

Operative Standardisierung bei randomisiert kontrollierten Studien in der Chirurgie

BACKGROUND

INSECT is an internationally registered, three-armed, multicentre, intraoperatively randomised model trial of the Study Centre of the German Surgical Society. The interventions being compared are running suture technique with slowly absorbable monofilament suture material (PDS vs MonoPlus) and interrupted technique with a braided, rapidly absorbable suture material (Vicryl). The primary endpoint is the rate of incisional hernias 1 year postoperatively.

MATERIAL AND METHODS

A total of 25 surgeons from 24 different institutions at all levels of care evaluated the theoretical and practical sessions of the surgical investigator meeting using 25 criteria, including course organisation, content, and speaker evaluation, and a categorical grading system from 1 (very good) to 6 (insufficient).

RESULTS

Distribution of the 625 grades was: very good (1) n=367, good (2) n=207, satisfactory (3) n=39, adequate (4) n=2, and "No statement" n=10. The average score for the investigator meeting was 1.5.

CONCLUSION

The participants felt they were successfully prepared theoretically and practically for trial interventions and conduct by attending the meeting. Clear explanation of the measures for treatment equivalence before and during trials is mandatory in randomised controlled surgical trials.