An international assessment of surgeon practices in abdominal wound closure and surgical site infection prevention by the European Society for Coloproctology

The burden of abdominal wound failure can be profound. Recent clinical guidelines have highlighted the heterogeneity of laparotomy closure techniques. The aim of this study was to investigate current midline closure techniques and practices for prevention of surgical site infection (SSI).


INTRODUC TI ON
Wound complications are common causes of both early and late morbidity following abdominal surgery [1]. Despite increased focus, surgical site infection (SSI) remains the second most common type of healthcare-related infection and among the most preventable hospital-acquired complications [2]. In a setting of limited resources, SSI is the leading cause of infection in the general patient population. It also affects over 65% of surgical patients and frequency rates are up to nine times higher than in developed countries [3]. The additional costs to a healthcare system are profound, especially if both direct costs (hospital costs) and indirect costs (sick leave) are calculated [4].
Failure of surgical wound healing can be largely attributed to mechanical failure or to patient-related issues, and can result in SSI, dehiscence and/or incisional hernia. SSI is especially concerning after colorectal surgery, with rates around 24%; and up to 31.8% of colorectal patients develop incisional hernia 2 years after standard mass closure [5,6]. SSI and incisional hernia have multiple causes; well-known risk factors include obesity, contamination grade, diabetes, operating time, American Society of Anesthesiologists score >3 and massive perioperative blood transfusion [7,8].
Prevention of SSI and wound dehiscence is paramount to minimizing morbidity. Various strategies have been postulated to mitigate risk, including alternative antiseptic skin preparations [9,10] prophylactic use of antimicrobials, varying closure techniques [11,12] and other adjuncts (negative-pressure wound dressings, hyperbaric oxygen therapy, high-dose multivitamins etc.) [13]. Despite numerous studies, there remains no clear international consensus on 'best' practice.
Currently, The European Hernia Society recommends a continuous suture with a slowly absorbable monofilament and small bite technique with a suture-to-wound length ratio of at least 4:1 [14].
However, in clinical practice, implementation of this recommendation has not been widespread [15]. Additionally, others advocate a combination of mechanical bowel preparation (MBP) and oral antibiotics to reduce SSI and incisional hernia rates [11], but less than 10% of European surgeons routinely use preoperative oral antibiotics and MBP [16].
Despite these recommendations, the incidence of both SSI and incisional hernia remain unacceptably high and complete prevention seems an unattainable goal. Heterogeneity in clinical practice means that any large-scale study would present difficulty in control of confounders without better understanding of current variations in practice. Therefore, the aim of this study was to investigate current practice and variability in abdominal wound closure strategies at a surgeon level.

ME THOD Design
A cross-sectional survey was designed to capture individual surgeons' opinions and practices of abdominal wound closure and SSI prevention strategies.

Informed consent process
All participants voluntarily participated in this closed online survey in English. No incentives were offered, and institutional review board permission was not required.

Development, pretesting and design
Study data were collected and managed using REDCap (Research Electronic Data Capture) tools hosted at the University of Birmingham, United Kingdom [17,18]. Study-specific databases were created using data dictionaries provided by the research team.
Once consensus was reached by the research team on the entire data collection case report form package, the application was moved to production status for study initiation [17,18]. The survey was constructed around three different patient scenarios that were expected to highlight differences in stratification of clinical decision making by surgeons. Scenarios were developed and ratified by the study design team during several online meetings. In addition, surgeons' daily clinical practice of SSI prevention strategies was investigated using a list of 18 specific interventions. Usability and technical functionality of the electronic questionnaire were tested by members of the European Society of Coloproctology (ESCP) Research Committee before dissemination. Survey items were not randomized or alternated. Adaptive questioning was used for a limited number of questions to reduce complexity (e.g. type of suture or needle size). In the final online format, all 44 questions were distributed on one page without a review step before submission. All questions were marked as mandatory, and the survey could only be submitted once all questions were answered. Once submitted, there was no opportunity to change answers.

Data analysis and reporting
Only respondents who completed the survey were considered eligible for the analysis. Study reporting was planned according to The Checklist for Reporting Results of Internet E-Surveys (CHERRIES) checklist [19]. Considering the study design and risk of selection bias, only descriptive analyses were planned for and differences between European and non-European countries and between consultants and trainee surgeons were explored with chi-square and Fisher's exact tests using SPSS 25.0 (IBM SPSS Statistics for Windows, version 25.0, Armonk, NY: IBM Corp.). p-values below 0.05 were considered statistically significant.

RE SULTS
A total of 561 participants completed the survey, 417/561 respondents left email addresses. Of these, two-thirds were from Europe (n = 375, 66.8%) with the remaining being located across the globe ( Figure 1).
The most frequently used skin preparation solution was 2% alcohol CHG (47.9% often/always). All other solutions were rated as Never/Rarely used more than 50% of the time (range 55.5%-76.6%) (see Figure 3).

F I G U R E 1 Overview of global study participation.
Out of the 11 other SSI prevention interventions, six were commonly used with more than 50% Often/Always ratings (range 54.9%-78.6%) and five interventions were not commonly used with Rarely/Never ratings greater than 50% (range 62.5%-78.4%) (see Figures 4 and 5, respectively).   Table S4 for details).
A continuous 2/0 polydioxanone suture with a small needle aligns with fascial healing time [24]. In the present study, most responders selected the small bites technique in all three scenarios (59.5% vs. 74.5% vs 58.6%). Considering that over 50% of these respondents declared a mass closure technique, many not reporting the use of 2/0 polydioxanone, the surgeons adopting small bites closure are more likely to range between 25% and 34.9% depending on the scenario, this being more consistent with the literature. 14.6%) and the lowest rates with off midline extraction, i.e. in the right or left lower abdominal quadrant (n = 13, 3.3%). Interestingly, the latter increased the risk of incisional hernia by a factor of 3.6 compared with Pfannenstiel incision [27].
In our survey many of the commonly used interventions aligned with recent recommendations by the World Health Organization (WHO) and/or National Institute for Health and Care Excellence 2019 SSI prevention guidelines (social cleaning, use of clippers for hair removal, use of wound protectors, wound irrigation, alcoholic CHG skin preps) [28,29]. Others have not been so recommended due to a lack of evidence (changing gloves and instruments before closure). More specifically, the WHO recommends the use of 2% alcoholic CHG skin preparation and triclosan-coated sutures.
Several multicomponent bundles including these interventions have been reported to reduce SSI rates after colorectal surgery [28,[30][31][32][33]. In a study by Dixon et [37]. However, the study population was not limited to colorectal surgery, and included a relatively high proportion of emergency and dirty operations. Further research in colorectal patients -especially in emergency and contaminated-dirty settings, is therefore indicated to guide clinical practice.
Concerning MBP, the addition of oral antibiotics remains equivocal. Moreover, we found that more non-Europeans reported using MPB only than Europeans. Several RCTs observe that oral antibiotics are effective in reducing SSI after colonic surgery [38,39], but adding MBP might not add benefits in this population [40][41][42]. The current study confirmed the variability and uncertainty of colorectal surgeons concerning preoperative bowel preparation observed in a survey of ESCP members [16].
Our study has limitations. As the survey was widely dissem-

E TH I C S S TATEM ENT
All participants gave informed consent before engaging in the questionnaire. Data were handled according to the Declaration of Helsinki.

FU N D I N G I N FO R M ATI O N
The study was supported by Ethicon.

CO N FLI C T O F I NTER E S T S TATEM ENT
None.

DATA AVA I L A B I L I T Y S TAT E M E N T
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions. Thank you for completing the questionnaire.

James Keatley on behalf of the ESCP Cohort Studies and Audit
Committee.

ESCP Project Manager.
University of Birmingham (United Kingdom).

ESCP Survey on Abdominal Wound Closure and SSI Prevention
Strategies.
ESCP is investigating the variety in wound closure techniques and surgical site infection preventive strategies. We hope to gather as many individual responses as possible and would be grateful if you could complete the survey which should take no longer than 5-10 minutes.
Please feel free to share the link to the survey with your colleagues also.
For information on how the University will use any personal data we collect please click here.