Mechanical plus oral bowel preparation with paromomycin and metronidazole reduces infectious complications in elective colorectal surgery: a matched case-control study

Is triggering receptor expressed on myeloid cell 1 (TREM-1) protein a new marker of serious infectious complications in colorectal surgery?: case-matched pilot study

PURPOSE

The purpose of the study was to evaluate the usefulness of the triggering receptor expressed on myeloid cell 1 (TREM-1) protein as a marker for serious infectious complications during laparoscopic colorectal surgery.

METHODS

Sixty-four patients with colon or rectal cancer, who underwent an elective laparoscopic colorectal cancer surgery from November 2018 to February 2020, were included in the analysis. Blood samples of the TREM-1 protein testing were collected four times from each patient: before and on three following postoperative days (PODs). Patients were divided into two groups according to the presence of infectious complications. Subsequently, patients with infectious complications (group 1) were matched 1:1 with patients without complications (group 2). The case-matched analysis was done by selecting patients from the control group by age, ASA scale, cancer stage, and type of surgery.

RESULTS

There was no significant difference in demographic and operative characteristics between the two groups. The median length of hospital stay was longer in group 1 than in group 2 (11 days vs. 5 days, p < 0.001). Preoperative measurements of TREM-1 protein did not differ between the two groups. There were no significant differences in the measurements on the first and third postoperative days. However, the median TREM-1 measurement was higher in group 1 on the second postoperative day (542 pg/ml vs. 399 pg/ml; p = 0.040). The difference was more apparent when only severe postoperative complications were considered. When compared to the group without any complications, the median TREM-1 level was significantly higher in the group with severe infection complications in POD 1, POD 2, and POD 3 (p < 0.05). The receiver operating characteristic (ROC) curve demonstrated that TREM-1 readings in POD 2 had a sensitivity of 83% and a specificity of 84% for the presence of severe infection complications at a value of 579.3 pg/ml (AUC 0.8, 95%CI 0.65-0.96).

CONCLUSION

TREM-1 measurements might become a helpful predictive marker in the early diagnosis of serious infectious complications in patients following laparoscopic colorectal surgery.

Rectal colonization is predictive for surgical site infections with multidrug-resistant bacteria in abdominal surgery

PURPOSE

Superficial surgical site infections (SSI) are a common complication after abdominal surgery. Additionally, multidrug-resistant organisms (MDRO) have shown an increasing spread in recent years with a growing importance for health care. As there is varying evidence on the importance of MDRO in different surgical fields and countries as causative agents of SSI, we report our findings of MDRO-caused SSI.

METHODS

We assembled an institutional wound register spanning the years 2015-2018 including all patients with abdominal surgery and SSI only, including demographics, procedure-related data, microbiological data from screenings, and body fluid samples. The cohort was examined for the frequency of different MDRO in screenings, body fluids, and wound swabs and assessed for risk factors for MDRO-positive SSI.

RESULTS

A total of 138 out of 494 patients in the register were positive for MDRO, and of those, 61 had an MDRO isolated from their wound, mainly multidrug-resistant Enterobacterales (58.1%) followed by vancomycin-resistant Enterococcus spp. (19.7%). As 73.2% of all MDRO-carrying patients had positive rectal swabs, rectal colonization could be identified as the main risk factor for an SSI caused by a MDRO with an odds ratio (OR) of 4.407 (95% CI 1.782-10.896, p = 0.001). Secondly, a postoperative ICU stay was also associated with an MDRO-positive SSI (OR 3.73; 95% CI 1.397-9.982; p = 0.009).

CONCLUSION

The rectal colonization status with MDRO should be taken into account in abdominal surgery regarding SSI prevention strategies. Trial registration Retrospectively registered in the German register for clinical trials (DRKS) 19th December 2019, registration number DRKS00019058.

Preoperative combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery

BACKGROUND

The success of elective colorectal surgery is mainly influenced by the surgical procedure and postoperative complications. The most serious complications include anastomotic leakages and surgical site infections (SSI)s, which can lead to prolonged recovery with impaired long-term health.  Compared with other abdominal procedures, colorectal resections have an increased risk of adverse events due to the physiological bacterial colonisation of the large bowel. Preoperative bowel preparation is used to remove faeces from the bowel lumen and reduce bacterial colonisation. This bowel preparation can be performed mechanically and/or with oral antibiotics. While mechanical bowel preparation alone is not beneficial, the benefits and harms of combined mechanical and oral antibiotic bowel preparation is still unclear.

OBJECTIVES

To assess the evidence for the use of combined mechanical and oral antibiotic bowel preparation for preventing complications in elective colorectal surgery.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL and trial registries on 15 December 2021. In addition, we searched reference lists and contacted colorectal surgery organisations.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adult participants undergoing elective colorectal surgery comparing combined mechanical and oral antibiotic bowel preparation (MBP+oAB) with either MBP alone, oAB alone, or no bowel preparation (nBP). We excluded studies in which no perioperative intravenous antibiotic prophylaxis was given.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as recommended by Cochrane. Pooled results were reported as mean difference (MD) or risk ratio (RR) and 95 % confidence intervals (CIs) using the Mantel-Haenszel method. The certainty of the evidence was assessed with GRADE.

MAIN RESULTS

We included 21 RCTs analysing 5264 participants who underwent elective colorectal surgery. None of the included studies had a high risk of bias, but two-thirds of the included studies raised some concerns. This was mainly due to the lack of a predefined analysis plan or missing information about the randomisation process. Most included studies investigated both colon and rectal resections due to malignant and benign surgical indications. For MBP as well as oAB, the included studies used different regimens in terms of agent(s), dosage and timing.  Data for all predefined outcomes could be extracted from the included studies. However, only four studies reported on side effects of bowel preparation, and none recorded the occurrence of adverse effects such as dehydration, electrolyte imbalances or the need to discontinue the intervention due to side effects. Seventeen trials compared MBP+oAB with sole MBP. The incidence of SSI could be reduced through MBP+oAB by 44% (RR 0.56, 95% CI 0.42 to 0.74; 3917 participants from 16 studies; moderate-certainty evidence) and the risk of anastomotic leakage could be reduced by 40% (RR 0.60, 95% CI 0.36 to 0.99; 2356 participants from 10 studies; moderate-certainty evidence). No difference between the two comparison groups was found with regard to mortality (RR 0.87, 95% CI 0.27 to 2.82; 639 participants from 3 studies; moderate-certainty evidence), the incidence of postoperative ileus (RR 0.89, 95% CI 0.59 to 1.32; 2013 participants from 6 studies, low-certainty of evidence) and length of hospital stay (MD -0.19, 95% CI -1.81 to 1.44; 621 participants from 3 studies; moderate-certainty evidence). Three trials compared MBP+oAB with sole oAB. No difference was demonstrated between the two treatment alternatives in terms of SSI (RR 0.87, 95% CI 0.34 to 2.21; 960 participants from 3 studies; very low-certainty evidence), anastomotic leakage (RR 0.84, 95% CI 0.21 to 3.45; 960 participants from 3 studies; low-certainty evidence), mortality (RR 1.02, 95% CI 0.30 to 3.50; 709 participants from 2 studies; low-certainty evidence), incidence of postoperative ileus (RR 1.25, 95% CI 0.68 to 2.33; 709 participants from 2 studies; low-certainty evidence) or length of hospital stay (MD 0.1 respectively 0.2, 95% CI -0.68 to 1.08; data from 2 studies; moderate-certainty evidence). One trial (396 participants) compared MBP+oAB versus nBP. The evidence is uncertain about the effect of MBP+oAB on the incidence of SSI as well as mortality (RR 0.63, 95% CI 0.33 to 1.23 respectively RR 0.20, 95% CI 0.01 to 4.22; low-certainty evidence), while no effect on the risk of anastomotic leakages (RR 0.89, 95% CI 0.33 to 2.42; low-certainty evidence), the incidence of postoperative ileus (RR 1.18, 95% CI 0.77 to 1.81; low-certainty evidence) or the length of hospital stay (MD 0.1, 95% CI -0.8 to 1; low-certainty evidence) could be demonstrated.

AUTHORS' CONCLUSIONS

Based on moderate-certainty evidence, our results suggest that MBP+oAB is probably more effective than MBP alone in preventing postoperative complications. In particular, with respect to our primary outcomes, SSI and anastomotic leakage, a lower incidence was demonstrated using MBP+oAB. Whether oAB alone is actually equivalent to MBP+oAB, or leads to a reduction or increase in the risk of postoperative complications, cannot be clarified in light of the low- to very low-certainty evidence. Similarly, it remains unclear whether omitting preoperative bowel preparation leads to an increase in the risk of postoperative complications due to limited evidence. Additional RCTs, particularly on the comparisons of MBP+oAB versus oAB alone or nBP, are needed to assess the impact of oAB alone or nBP compared with MBP+oAB on postoperative complications and to improve confidence in the estimated effect. In addition, RCTs focusing on subgroups (e.g. in relation to type and location of colon resections) or reporting side effects of the intervention are needed to determine the most effective approach of preoperative bowel preparation.

Mechanical bowel preparation combined with oral antibiotics reduces infectious complications and anastomotic leak in elective colorectal surgery: a pooled-analysis with trial sequential analysis

OBJECTIVE

A pooled analysis combined with trial sequential analysis (TSA) was conducted in order to explore the effect of mechanical bowel preparation (MBP) combined with oral antibiotic bowel decontamination (OAB) versus MBP alone on patients who have undergone colorectal resection.

METHODS

Comprehensive and systematic searches of PubMed, Embase, Cochrane Library, Web of Knowledge, and Clinical Trials.gov databases were conducted. The quality of literature was evaluated using Cochrane risk bias assessment tool as well as Newcastle-Ottawa Scale (NOS) score. A pooled analysis of randomized controlled trials (RCTs) and prospective studies was performed comparing patients who underwent colorectal resection and received MBP plus OAB or MBP alone. The outcome endpoints were the incidence of anastomotic leak (AL) and surgical site infection (SSI). TSA is a tool used to assess the reliability of currently available evidence to determine further clinical trial validation.

RESULTS

The analysis included a total of 22 studies involving 8852 patients, including 3016 patients in the MBP + OAB group and 4415 patients exposed to MBP alone. The pooled analysis showed that the incidence of postoperative anastomotic leak was significantly lower in the group treated with MBP plus OAB compared with MBP alone (OR = 0.43, 95% CI: 0.23-0.81, P = 0.009, I2 = 73%). The incidence of postoperative surgical site infections was significantly lower in the group exposed to the combination of MBP and OAB compared with MBP alone (OR = 0.38, 95% CI: 0.32-0.46, P < 0.0001, I2 = 24%). The TSA demonstrated significant benefits of MBP plus OAB intervention in terms of AL and SSI.

CONCLUSION

MBP combined with OAB significantly reduces the incidence of AL and SSI in patients after colorectal resection compared with MBP alone.