Oral Antibiotic Prophylaxis Reduces Surgical Site Infection and Anastomotic Leakage in Patients Undergoing Colorectal Cancer Surgery

Comparison of the Efficacy of Cephalosporins and Non-cephalosporins in Preventing Surgical Site Infections in Colorectal Surgery Patients: An Updated Systematic Review and Meta-Analysis

OBJECTIVE

This study aims to compare the efficacy of cephalosporin and non-cephalosporin antibiotics in preventing surgical site infections (SSIs) in patients undergoing colorectal surgery, providing a scientific basis for the selection of perioperative antibiotics through systematic review and meta-analysis.

METHODS

Adhering to the PRISMA guidelines, this research employed an extensive literature search strategy across multiple databases to identify relevant studies, including randomized controlled trials (RCTs) and observational studies. Inclusion criteria were studies on adults undergoing colorectal surgery who received preoperative prophylaxis with either cephalosporin or non-cephalosporin antibiotics. Exclusion criteria included preoperative diagnosis of infectious diseases and preoperative use of antimicrobial agents. Meta-analysis was conducted using RevMan 5.3 software to assess the effectiveness of both antibiotic classes in preventing SSIs, including subgroup analyses.

RESULTS

Eight studies met the inclusion criteria, comprising 872 patients. Meta-analysis revealed that the incidence of SSI in the cephalosporin group was lower than in the non-cephalosporin group (14.8% vs 25.1%), with statistical significance (OR = 1.94, 95% CI: 1.38-2.74, PP = =0.0001). However, no significant difference in SSI risk was observed between the groups within 30 days (OR = =1.92, 95% CI: 1.08-3.42). Subgroup analysis indicated that higher-quality studies were associated with larger effect sizes.

CONCLUSION

This study suggests that cephalosporin antibiotics may be superior to non-cephalosporins in preventing SSIs following colorectal surgery, especially in the short term. However, their long-term efficacy in SSI prevention may be similar. The selection of perioperative antibiotics should consider factors such as the antimicrobial spectrum, pharmacokinetic properties, and bacterial resistance.

Effects of diet and antibiotics on anastomotic healing: A mouse model study with varied dietary fiber and fat, and pre-operative antibiotics

INTRODUCTION

This study investigated the separate impacts of diet and pre-operative antibiotics on gut microbiome and colonic anastomotic healing using a mouse model.

METHODS

Male C57BL/6J mice were fed either low-fat-high-fibre (SD) or high-fat-low-fiber (WD) groups for 6 weeks, then further received either pre-operative antibiotics or a control sham before a colonic anastomotic procedure was performed. After 7 days, the anastomosis was assessed and microbiota composition and biodiversity were analyzed in anastomotic tissue and stool.

RESULTS

WD-fed mice had shorter survival (5.2 ​± ​2.3 vs. 6.9 ​± ​2.3 days, p ​= ​0.022), increased weight loss (5.55 ​± ​3.80g vs. 2.65 ​± ​2.36g, p ​= ​0.03), and reduced biodiversity compared to SD-fed mice. Pre-operative antibiotics improved anastomotic healing scores (1.33 ​± ​0.65 vs. 2.08 ​± ​0.79, p ​= ​0.02) and reduced Enterococcus faecalis growth in tissue and stool (p ​= ​0.02, p ​= ​0.02). Improved anastomotic healing correlated with lower Enterococcus abundance (p ​= ​0.04) and higher collagen III and IV levels (p ​= ​0.01, 0.04) in anastomotic tissue.

CONCLUSION

SD promotes enhanced post-operative recovery and increased microbiome biodiversity, while pre-operative antibiotics enhance anastomotic healing by suppressing Enterococcus faecalis growth, mitigating collagen III/IV degradation.

Clinical Benefits of Reducing Dead Space Using a Closed Suction Drain and Subcutaneous Large-bite Buried Suture Technique to Prevent Superficial Surgical-site Infections Following Primary Closure of a Diverting Stoma

Objectives

Surgical-site infections (SSIs) are the most common complication after stoma closure. We propose a new method for wound closure using the subcutaneous large-bite buried suture (SLBS) technique and a closed suction drain (CSD). In this study, we aimed to investigate the efficacy of a combination of the SLBS technique and a CSD to prevent superficial SSIs following stoma closure.

Methods

We retrospectively analyzed patients who underwent stoma closure between January 2019 and July 2022. Primary closure of the stomal site was performed using the SLBS technique and a CSD for wound closure. The CSD was placed until postoperative day 7. The occurrence of superficial postoperative SSIs was also evaluated.

Results

In total, 67 patients were included in the study. Within 30 days postoperatively, nine patients (13%) developed superficial SSIs. Considering the type of stoma, only 1 (2%) of 45 patients with ileostomy showed superficial SSIs, whereas 8 (36%) of 22 patients with colostomy showed superficial SSIs. Univariate analysis of the risk factors associated with the occurrence of superficial SSIs revealed that colostomy (p < 0.001) and hand-sewn anastomosis were significant risk factors (p = 0.019). Multivariate analysis of the risk factors associated with the occurrence of superficial SSIs revealed that colostomy was significant risk factor (p = 0.003).

Conclusions

This new method of stoma closure is feasible for preventing superficial SSIs, especially in ileostomy closure.

Cost-effectiveness of selective decontamination of the digestive tract to decrease infectious complications in colorectal cancer surgery: An analysis of the SELECT trial

INTRODUCTION

Selective decontamination of the digestive tract (SDD) is effective in reducing infectious complications in elective colorectal cancer (CRC) surgery. However, it is unclear whether SDD is cost-effective compared to standard antibiotic prophylaxis.

MATERIAL & METHODS

Economic evaluation alongside multicenter randomized controlled trial, the SELECT-trial, from a healthcare perspective. Patients included underwent elective surgery for non-metastatic CRC. The intervention group received oral non-absorbable colistin, tobramycin and amphotericin B (SDD) next to standard antibiotic prophylaxis. Both groups received a single shot intravenous cefazolin and metronidazole preoperatively as standard prophylaxis. Occurrence of postoperative infectious complication in the first 30 postoperative days was extracted from medical records, Quality-Adjusted Life-Years (QALYs) based on the ED-5D-3L, and healthcare costs collected from the hospital's financial administration.

RESULTS

Of the 455 patients, 228 were randomly assigned to intervention group and 227 patients to the control group. SDD significantly reduced the number of infectious complications compared to control (difference = -0.13, 95 % CI -0.05 to -0.20). No difference was found for QALYs (difference = 0.002, 95 % CI -0.002 to 0.005). Healthcare costs were statistically significantly lower in the intervention group (difference = -€1258, 95 % CI -2751 to -166). The ICER was -9872 €/infectious complication prevented and -820,380 €/QALY gained. For all willingness-to-pay thresholds, the probability that prophylactic SDD was cost-effective compared to standard prophylactic practice alone was 1.0.

CONCLUSION

The addition of SDD to the standard preoperative intravenous antibiotic prophylaxis is cost-effective compared to standard prophylactic practice from a healthcare perspective and should be considered as the standard of care.

Anastomotic leak in colorectal cancer surgery: Contribution of gut microbiota and prediction approaches

AIM

To monitor prospectively the occurrence of colorectal anastomotic leakage (CAL) in patients with colon cancer undergoing resectional surgery, characterizing the microbiota in both faeces and mucosal biopsies of anastomosis. In a second stage, we investigated the ability to predict CAL using machine learning models based on clinical data and microbiota composition.

METHOD

A total of 111 patients were included, from whom a faecal sample was obtained, as well as biopsy samples from proximal and distal sites in the healthy margins of the tumour piece. The microorganisms present in the samples were investigated using microbial culture and 16S rDNA massive sequencing. Collagenase and protease production was determined, as well as the presence of genes responsible for expressing enzymes with these activities. Machine learning analyses were developed using clinical and microbiological data.

RESULTS

The incidence of CAL was 9.0%, and CAL was associated with collagenase/protease-producing Enterococcus. Significant differences were found in the microbiota composition of proximal and distal biopsy samples, but not in faecal samples, among patients who developed CAL. Clinical predictors of CAL were 5-day C-reactive protein and heart disease, whereas 3-day C-reactive protein and diabetes were negative predictors.

CONCLUSION

Biopsy samples from surgical margins, rather than faecal samples, are the most appropriate samples for exploring the contribution of the intestinal microbiota to CAL. Enterococci are only enriched in the anastomosis after surgery, and their collagenases and proteases are involved in the degradation of the anastomotic scar.

How to prevent postoperative ileus in colorectal surgery? a systematic review

Postoperative ileus (PI) after colorectal surgery is a common surgical problem. This systematic review aimed to investigate the available data in the literature to reduce the PI in the area of colorectal surgery out of the enhanced recovery after surgery principles, referring to published randomized controlled trials (RCTs) and meta-analyses, and to provide recommendations according to the Oxford Centre for Evidence-Based Medicine. The authors conducted bibliographic research on 1 December 2022. The authors retained meta-analyses and RCTs. The authors concluded that when we combined colonic mechanical preparation with oral antibiotic decontamination, the authors found a significant reduction in PI. The open approach was associated with a higher PI rate. The robotic and laparoscopic approaches had similar PI rates. Low ligation of the inferior mesenteric artery presented a PI similar to that of high ligation of the inferior mesenteric artery. There was no difference between the isoperistaltic and antiperistaltic anastomoses or between the intracorporeal and extracorporeal anastomoses. This study summarized the available data in the literature, including meta-analyses and RCTs. For a higher level of evidence, additional multicenter RCTs and meta-analyses of RCTs remain necessary.

Oral antibiotics and mechanical bowel preparation for colorectal surgery: A prospective observational study of surgical site infection and microbial analysis

PURPOSE

Surgical site infections (SSIs) are common in colorectal surgery. Mechanical bowel preparation (MBP) in conjunction with oral antibiotics (OABs) have been shown to reduce SSI rates. It however is still unclear which OABs to use, and how this can be implemented in practice.

METHODS

This is a prospective observational study carried out in Swansea Bay University Health Board during 2019-2021, evaluating the introduction of OABs in a stepwise manner on the incidence of SSI in major colorectal surgery. A control group having MBP only was compared to two OAB groups: one group had MBP plus metronidazole only and the second MBP plus metronidazole and neomycin. A 30-day follow-up after surgery was ascertained via chart review and telephone contact. Logistic regression was performed to estimate the relation between OAB use and SSI, with adjustment for confounding. In a subset of patients, faecal samples were analysed through 16S rRNA amplicon sequencing before and after OAB treatment, depicting the impact of the gut microbiome.

RESULTS

In total 160 patients were analysed: 46 patients had MBP only, whilst 76 patients had MBP plus metronidazole only and 38 patients had MBP with metronidazole/neomycin. The SSI rate in the entire cohort was 33.8%, whilst the adjusted ORs for the single- and dual-OAB groups were 0.76 (95% CI: 0.17-1.81) and 0.50 (95% CI: 0.17-1.52). The microbial analysis demonstrated that the relative abundance for many bacterial genera was changed before and after OAB treatment, but no link with SSI development could be shown.

CONCLUSIONS

Introduction of OABs in conjunction with MBP in colorectal surgery is feasible, and may potentially lead to lower rates of SSI, as well as altering the community structure of the faecal microbiome. More research is needed, especially considering different OABs and mechanistic studies of the gut microbiome in the context of colorectal surgery.

Selective Decontamination with Oral Antibiotics in Colorectal Surgery: 90-day Reintervention Rates and Long-term Oncological Follow-up

BACKGROUND

Oral antibiotics (OAB) in colorectal surgery have been shown to reduce surgical site infections (SSIs) and possibly anastomotic leakage. However, evidence on long-term follow-up, reintervention rates and 5-year oncological follow-up is lacking. The current study aims at elucidating this knowledge gap.

METHODS

This study evaluated the long-term effectiveness of perioperative 'Selective decontamination of the digestive tract' (SDD) in colorectal cancer surgery. The primary outcome was anastomotic leakage within 90 days, secondary outcomes included infectious complications, reinterventions, readmission, hospital stay, and 5-year overall and disease-free-survival. Statistical analysis including univariate and multivariate analysis was performed to identify predictors of 90-day outcomes, and Kaplan-Meier survival analysis was used for the 5-year survival outcomes.

RESULTS

In total 455 patients were analyzed, 228 participants in the SDD group and 227 in the control group. Anastomotic leakage rate was not statistically different between the SDD and control group (6.6% versus 9.7%). One or more infectious complications occurred in 15.4% of patients in the SDD group and in 28.2% in the control group (OR 0.46, 95% C.I. 0.29 - 0.73). In the SDD group 8,8% of patients required a reintervention compared to 16,3% of patients in the control group (OR 0.47, 95% C.I. 0.26 - 0.84). After multivariable analysis SDD remained significant in reducing both infectious complications and reinterventions after 90-days follow-up. There was no difference between SDD and control group in 5-year overall survival and disease-free-survival.

CONCLUSION

SDD as OAB is effective in reducing 90-days postoperative infectious complications and reinterventions. As such, SDD as standard OAB in elective colorectal surgery is highly recommended.

Predictive Factors for Anastomotic Leakage Following Colorectal Cancer Surgery: Where Are We and Where Are We Going?

Anastomotic leakage (AL) remains one of the most severe complications following colorectal cancer (CRC) surgery. Indeed, leaks that may occur after any type of intestinal anastomosis are commonly associated with a higher reoperation rate and an increased risk of postoperative morbidity and mortality. At first, our review aims to identify specific preoperative, intraoperative and perioperative factors that eventually lead to the development of anastomotic dehiscence based on the current literature. We will also investigate the role of several biomarkers in predicting the presence of ALs following colorectal surgery. Despite significant improvements in perioperative care, advances in surgical techniques, and a high index of suspicion of this complication, the incidence of AL remained stable during the last decades. Thus, gaining a better knowledge of the risk factors that influence the AL rates may help identify high-risk surgical patients requiring more intensive perioperative surveillance. Furthermore, prompt diagnosis of this severe complication may help improve patient survival. To date, several studies have identified predictive biomarkers of ALs, which are most commonly associated with the inflammatory response to colorectal surgery. Interestingly, early diagnosis and evaluation of the severity of this complication may offer a significant opportunity to guide clinical judgement and decision-making.

Is There a Role for Mechanical and Oral Antibiotic Bowel Preparation for Patients Undergoing Minimally Invasive Colorectal Surgery? A Systematic Review and Meta-analysis

INTRODUCTION

To date, all meta-analyses on oral antibiotic prophylaxis (OA) and mechanical bowel preparation (MBP) in colorectal surgery have included results of both open and minimally invasive approaches. Mixing both procedures may lead to false conclusions. The aim of the study was to assess the available evidence of mechanical and oral antibiotic bowel preparation in reducing the incidence of surgical site infection (SSI) and other complications following minimally invasive elective colorectal surgery.

METHODS

We searched PubMed, Science Direct, Google Scholar and Cochrane Library from 2000 to May 1, 2022. Comparative randomized and non-randomized studies were included. We reviewed the use of oral OA, MBP and combinations of these treatments. The methodological quality of the included studies was assessed using the Rob v2 and Robins-I tools.

RESULTS

We included 18 studies (7 randomized controlled trials and 11 cohort studies). Meta-analysis of the included studies showed that the combination of MBP + OA was associated with a significant reduction in SSI, AL and overall morbidity compared with the other options no preparation, MBP only and OA only.  CONCLUSION: Adding OA with MBP has a positive impact in reducing the incidence of SSI, AL and overall morbidity after minimally invasive colorectal surgery. Therefore, the combination of OA and MBP should be encouraged in this selected group of patients undergoing minimally invasive surgery.

Mechanical bowel preparation with or without oral antibiotics for rectal resection for cancer (REPCA trial): a study protocol for a multicenter randomized controlled trial

BACKGROUND

There is still a lack of randomized trials assessing the clinical value of mechanical bowel preparation (MBP) and oral antibiotics (OA) before rectal surgery. Existing studies are inconsistent regarding OA. The aim of this study is to examine the role of MBP with or without OA (using Alfa Normix^®) on postoperative complications in patients undergoing rectal resection for cancer.

METHODS

We are conducting a prospective multicenter randomized controlled trial comparing MBP (Moviprep^®) with OA (Alfa Normix^®) versus MBP alone in patients undergoing elective rectal resection for cancer. Patients with rectal or rectosigmoid cancer are randomized in a 1:1 allocation ratio. The primary endpoint is incisional surgical site infection (SSI) assessed within 30 days after surgery. Secondary endpoints are anastomotic leakage (AL), organ/space SSI, other postoperative complications, intraoperative complications, operation time, bowel preparation quality, bowel preparation adherence. Intention-to-treat and per protocol analyses will be performed.

CONCLUSIONS

The results of the REPCA trial will demonstrate whether MBP + OA is superior to MBP alone in rectal cancer surgery. This trial might influence current preoperative practice and improve postoperative outcomes.

Comparative effectiveness of oral antibiotics, probiotics, prebiotics, and synbiotics in the prevention of postoperative infections in patients undergoing colorectal surgery: A network meta-analysis

Oral antibiotics (OAB), probiotics, prebiotics, and synbiotics are reported to be effective for preventing postoperative infection following colorectal surgery, but the comparative effectiveness between them has not been studied. To compare these interventions through a network meta-analysis. Ovid Medline, Embase, and the Cochrane Controlled Register of Trials (CENTRAL) were searched from inception to January 1, 2022 without any language restriction. Two reviewers independently screened the retrieved articles, assessed risk of bias, and extracted information from the included randomised controlled trials (RCTs). The primary outcome was infection rate, and the secondary outcome was anastomotic leakage rate. 4322 records were retrieved after literature search, and 20 RCTs recruiting 3726 participants were finally included. The analysis showed that usual care (UC) + Synbiotics ranked the most effective treatment (SUCRA = 0.968), UC + OAB ranked the second (SUCRA = 0.797), and UC + IAB ranked the third (SUCRA = 0.678) for preventing postoperative infection rate, but only UC + OAB achieved statistical significance. UC + OAB was the most effective treatment (SUCRA = 0.927) for preventing anastomotic leakage rate. Our study confirmed that preoperative administration of OAB was associated with lower infection rate and anastomotic leakage rate than placebo and UC alone. However, the beneficial effect of probiotics and synbiotics should still be investigated by large-scale randomised controlled trials.

Risk Factors and Preventive Measures for Anastomotic Leak in Colorectal Cancer

Anastomotic leak (AL) represents one of the most detrimental complications after colorectal surgery. The patient-related factors and surgery-related factors leading to AL have been identified in previous studies. Through early identification and timely adjustment of risk factors, preventive measures can be taken to reduce potential AL. However, there are still many problems associated with AL. The debate about preventive measures such as preoperative mechanical bowel preparation (MBP), intraoperative drainage, and surgical scope also continues. Recently, the gut microbiota has received more attention due to its important role in various diseases. Although the underlying mechanisms of gut microbiota on AL have not been validated completely, new strategies that manipulate intrinsic mechanisms are expected to prevent and treat AL. Moreover, laboratory examinations for AL prediction and methods for blood perfusion assessment are likely to be promoted in clinical practice. This review outlines possible risk factors for AL and suggests some preventive measures in terms of patient, surgery, and gut microbiota.