Mechanical bowel preparation and antimicrobial prophylaxis in elective colorectal surgery in Switzerland—a survey

Standardization of rectal cancer surgery and bowel preparation in Austria : A multicenter nationwide survey by the Austrian Society of Surgical Oncology

BACKGROUND

Standardized management of colorectal cancer is crucial for achieving an optimal clinical and oncological outcome. The present nationwide survey was designed to provide data about the surgical management of rectal cancer patients. In addition, we evaluated the standard approach for bowel preparation in all centers in Austria performing elective colorectal surgery.

METHODS

The Austrian Society of Surgical Oncology (ACO["Arbeitsgemeinschaft für chirurgische Onkonlogie"]-ASSO) conducted a multicenter questionnaire-based study comprising 64 hospitals between October 2020 and March 2021.

RESULTS

The median number of low anterior resections performed annually per department was 20 (range 0-73). The highest number was found in Vienna, with a median of 27 operations, whereas Vorarlberg was the state with the lowest median number of 13 resections per year. The laparoscopic approach was the standard technique in 46 (72%) departments, followed by the open approach in 30 (47%), transanal total mesorectal excision (TaTME) in 10 (16%) and robotic surgery in 6 hospitals (9%). Out of 64 hospitals 51 (80%) named a standard for bowel preparation before colorectal resections. No preparation was commonly used for the right colon (33%).

CONCLUSION

Considering the low number of low anterior resections performed in each hospital per year in Austria, defined centers for rectal cancer surgery are still scarce. Many hospitals did not transfer recommended bowel preparation guidelines into clinical practice.

A European survey of bowel preparation in colorectal surgery

AIM

Meta-analysis has shown that mechanical bowel preparation (MBP) does not improve outcomes in colonic surgery; however, there is uncertainty regarding MBP use in laparoscopic and rectal surgery and the addition of oral antibiotic regimens. The aim of this study was to assess current use of bowel preparation among European surgeons.

METHOD

An online survey was circulated to members of the European Society of Coloproctology. Chi-squared analysis was used to compare subgroups.

RESULTS

A total of 426 surgeons responded to the survey. MBP is routinely prescribed by 29.6% of respondents prior to colonic surgery and in 77.0% prior to rectal surgery. In the cohort performing > 30% of colorectal operations laparoscopically (n = 294), routine use of MBP in colonic surgery was significantly lower (19.7% vs 51.5%, P < 0.01). Less than 10% prescribe oral antibiotic bowel preparation whereas 96% prescribe perioperative intravenous antibiotics.

CONCLUSION

Among the majority of respondents to this survey, MBP is used routinely for rectal operations. For colonic surgery, laparoscopic surgeons have a significantly lower use of MBP. Use of oral antibiotic bowel preparation remains uncommon.

Surgical site infection and its risk factors in colon surgeries

Abstract OBJECTIVE To identify the occurrence of surgical site infection (SSI) and its risk factors in patients undergoing colon surgery in a tertiary hospital located in the countryside of the state of São Paulo. METHOD Retrospective cohort study, with collection of information contained in the medical records of patients undergoing colon surgery in the period between January 2010 and December 2013. The studied variables were the possible risk factors related to the patient, to demographic characteristics and the surgical procedure. RESULTS In total, were evaluated 155 patients with an overall SSI incidence of 16.7%. A statistically significant association was found both in the univariate as in the multivariate analysis between the SSI and the following variables: male gender, Charlson index and mechanical bowel preparation. CONCLUSION The understanding of health professionals about the factors that influence the incidence of SSI in colon surgery may contribute to the quality of care provided to surgical patients, from effective actions to minimize the risk of infections.

Antimicrobial prophylaxis for colorectal surgery

BACKGROUND

Research shows that administration of prophylactic antibiotics before colorectal surgery prevents postoperative surgical wound infection. The best antibiotic choice, timing of administration and route of administration remain undetermined.

OBJECTIVES

To establish the effectiveness of antimicrobial prophylaxis for the prevention of surgical wound infection in patients undergoing colorectal surgery. Specifically to determine:1. whether antimicrobial prophylaxis reduces the risk of surgical wound infection;2. the target spectrum of bacteria (aerobic or anaerobic bacteria, or both);3. the best timing and duration of antibiotic administration;4. the most effective route of antibiotic administration (intravenous, oral or both);5. whether any antibiotic is clearly more effective than the currently recommended gold standard specified in published guidelines;6. whether antibiotics should be given before or after surgery.

SEARCH METHODS

For the original review published in 2009 we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE (Ovid) and EMBASE (Ovid). For the update of this review we rewrote the search strategies and extended the search to cover from 1954 for MEDLINE and 1974 for EMBASE up to 7 January 2013. We searched CENTRAL on the same date (Issue 12, 2012).

SELECTION CRITERIA

Randomised controlled trials of prophylactic antibiotic use in elective and emergency colorectal surgery, with surgical wound infection as an outcome.

DATA COLLECTION AND ANALYSIS

Data were abstracted and reviewed by one review author and checked by another only for the single, dichotomous outcome of surgical wound infection. Quality of evidence was assessed using GRADE methods.

MAIN RESULTS

This updated review includes 260 trials and 68 different antibiotics, including 24 cephalosporins and 43,451 participants. Many studies had multiple variables that separated the two study groups; these could not be compared to other studies that tested one antibiotic and had a single variable separating the two groups. We did not consider the risk of bias arising from attrition and lack of blinding of outcome assessors to affect the results for surgical wound infection.Meta-analyses demonstrated a statistically significant difference in postoperative surgical wound infection when prophylactic antibiotics were compared to placebo/no treatment (risk ratio (RR) 0.34, 95% confidence interval (CI) 0.28 to 0.41, high quality evidence). This translates to a reduction in risk from 39% to 13% with prophylactic antibiotics. The slightly higher risk of wound infection with short-term compared with long-term duration antibiotic did not reach statistical significance (RR 1.10, 95% CI 0.93 to 1.30). Similarly risk of would infection was slightly higher with single-dose antibiotics when compared with multiple dose antibiotics, but the results are compatible with benefit and harm (RR 1.30, 95% CI 0.81 to 2.10). Additional aerobic coverage and additional anaerobic coverage both showed statistically significant improvements in surgical wound infection rates (RR 0.44, 95% CI 0.29 to 0.68 and RR 0.47, 95% CI 0.31 to 0.71, respectively), as did combined oral and intravenous antibiotic prophylaxis when compared to intravenous alone (RR 0.56, 95% CI 0.43 to 0.74), or oral alone (RR 0.56, 95% CI 0.40 to 0.76). Comparison of an antibiotic with anaerobic specificity to one with aerobic specificity showed no significant advantage for either one (RR 0.84, 95% CI 0.30 to 2.36). Two small studies compared giving antibiotics before or after surgery and no significant difference in this timing was found (RR 0.67, 95% CI 0.21 to 2.15). Established gold-standard regimens recommended in major guidelines were no less effective than any other antibiotic choice.

AUTHORS' CONCLUSIONS

This review has found high quality evidence that antibiotics covering aerobic and anaerobic bacteria delivered orally or intravenously (or both) prior to elective colorectal surgery reduce the risk of surgical wound infection. Our review shows that antibiotics delivered within this framework can reduce the risk of postoperative surgical wound infection by as much as 75%. It is not known whether oral antibiotics would still have these effects when the colon is not empty. This aspect of antibiotic dosing has not been tested. Further research is required to establish the optimal timing and duration of dosing, and the frequency of longer-term adverse effects such as Clostridium difficile pseudomembranous colitis.

Bowel Preparation before Elective Surgery

Mechanical bowel preps were initially thought to decrease the bacterial load of the colon and therefore decrease infection. Traditional bowel preps include osmotic, laxative, and combination regimen. Data demonstrate that mechanical bowel preps are generally equivalent; however, the addition of oral antibiotics may further reduce the risk of infection. Recent data suggest that mechanical bowel preparations may not be necessary, and that dietary restrictions before surgery may also be obsolete. In this review, the authors address the types of mechanical bowel preparations (MBPs), differences in outcomes between MBPs, the role of oral antibiosis and enemas, the benefits of no MBP, and dietary preparations for elective colon and rectal surgery.