Double-blind comparison of single-dose alatrofloxacin and cefotetan as prophylaxis of infection following elective colorectal surgery. Trovafloxacin Surgical Group

Tailored Pre-Operative Antibiotic Prophylaxis to Prevent Post-Operative Surgical Site Infections in General Surgery

The average American today undergoes three inpatient and two outpatient surgical procedures during one's life, each of which carries with it a risk of post-operative infection. It has long been known that post-operative infections cause significant morbidity in the immediate peri-operative period, but recent evidence suggests that they can have long-term consequences as well, increasing a patient's risk of infectious complications in unrelated surgeries performed months or even years later. While there are several theories on the origin of this association, including bacterial colonization of a post-operative infectious wound site, antimicrobial resistance from curative courses of antibiotics, subclinical immunosuppression, or the creation of an inflammatory "pathobiome" following an infectious insult, it is ultimately still unclear why patients who experience a single post-operative infection seem to be at a significantly higher risk of experiencing subsequent ones. Regardless, this association has significant implications for the routine use of pre-operative antibiotic prophylaxis. Indeed, while the prescription of antibiotics pre-operatively has dramatically reduced the rate of post-operative infections, the chosen prophylaxis regimens are typically standardized according to national guidelines, are facing increasing antimicrobial resistance patterns, and have been unable to reduce the risk of post-operative infection to acceptably low levels for certain surgeries. As a result, some clinicians have speculated that tailoring pre-operative antibiotic prophylaxis according to a patient's prior infectious and operative history could improve efficacy and further reduce the rate of post-operative infections. The purpose of this review is to describe the evidence for the link between multiple post-operative infections and explore the efficacy of individualized pre-operative prophylaxis.

Mismatch of populations between randomised controlled trials of perioperative interventions in major abdominal surgery and current clinical practice

BACKGROUND

Demographics of patients undergoing major abdominal surgery are changing. External validity of relevant RCTs may be limited by participants not resembling patients encountered in clinical practice. We aimed to characterise differences in age, weight, BMI, and ASA grade between participants in perioperative trials in major abdominal surgery and patients in a reference real-world clinical practice sample. The secondary aim was to investigate whether time since trial publication was associated with increasing mismatch between these groups.

METHODS

MEDLINE and Embase were searched for multicentre RCTs from inception to September 2022. Studies of perioperative interventions in adults were included. Studies that limited enrolment based on age, weight, BMI, or ASA status were excluded. We compared trial cohort age, weight, BMI, and ASA distribution to those of patients undergoing major abdominal surgery at our tertiary referral hospital during September 2021 to September 2022. We used a local, single-institution reference sample to reflect the reality of clinical practice (i.e. patients treated by a clinician in their own hospital, rather than averaged nationally). Mismatch was defined using comparison of summary characteristics and ad hoc criteria based on differences relevant to predicted mortality risk after surgery.

RESULTS

One-hundred and six trials (44,499 participants) were compared to a reference cohort of 2792 clinical practice patients. Trials were published a median (IQR [range]) 13.4 (5-20 [0-35]) years ago. A total of 94.3% of trials were mismatched on at least one characteristic (age, weight, BMI, ASA). Recruitment of ASA 3 + participants in trials increased over time, and recruitment of ASA 1 participants decreased over time (Spearman's Rho 0.58 and - 0.44, respectively).

CONCLUSIONS

Patients encountered in our current local clinical practice are significantly different from those in our defined set of perioperative RCTs. Older trials recruit more low-risk than high-risk participants-trials may thus 'expire' over time. These trials may not be generalisable to current patients undergoing major abdominal surgery, and meta-analyses or guidelines incorporating these trials may therefore be similarly non-applicable. Comparison to local, rather than national cohorts, is important for meaningful on-the-ground evidence-based decision-making.

Postoperative negative-pressure incision therapy following open colorectal surgery (Poniy): study protocol for a randomized controlled trial

BACKGROUND

Postoperative surgical site infections cause substantial morbidity, prolonged hospitalization, costs and even mortality, and remain one of the most frequent surgical complications. In prospective trials with adequate follow-up, more than 20 % of patients undergoing elective colorectal surgery are affected and methods to reduce surgical site infections are urgently needed. Negative-pressure incision therapy is a novel intervention that holds promise to reduce postoperative wound infection rates, but has not yet been rigorously tested in a randomized controlled trial.

METHODS/DESIGN

The aim is to investigate whether the postoperative application of a negative-pressure incision therapy device for 5-7 days reduces the rate of surgical site infections following open elective colorectal surgery by 50 %. This is a randomized, controlled, observer-blinded multicentre clinical trial with two parallel study groups. The primary outcome measure will be the rate of surgical site infections within 30 days postoperatively. Surgical site infections are defined according to criteria of the US Centers for Disease Control and Prevention. Statistical analysis of the primary endpoint measure will be based on the intention-to-treat population. The global level of significance is set at 5 % (two-sided) and the sample size (n = 170 per group) is determined to assure a power of 80 %.

DISCUSSION

The Poniy trial will explore whether the rate of surgical site infections can be reduced by the application of a negative-pressure incision therapy device in patients undergoing open elective colorectal surgery. Its pragmatic design guarantees high external validity and clinical relevance.

TRIAL REGISTRATION

Deutsches Register Klinischer Studien DRKS00006199 .

Multicenter double-blinded randomized controlled trial of standard abdominal wound edge protection with surgical dressings versus coverage with a sterile circular polyethylene drape for prevention of surgical site infections: a CHIR-Net trial (BaFO; NCT01181206)

OBJECTIVE

To determine whether circular plastic wound edge protectors (CWEPs) significantly reduce the rate of surgical site infections (SSIs) in comparison to standard surgical towels in patients undergoing laparotomy.

BACKGROUND

SSIs cause substantial morbidity, prolonged hospitalization, and costs and remain one of the most frequent surgical complications. CWEPs have been proposed as a measure to reduce the incidence of SSIs.

METHODS

In this randomized controlled, multicenter, 2-arm, parallel-group design, patient- and observer-blinded trial patients undergoing open elective abdominal surgery were assigned to either intraoperative wound coverage with a CWEP or standard coverage with surgical towels. Primary endpoint was superiority of intervention over control in terms of the incidence of SSIs within a 30-day postoperative period.

RESULTS

Between September 2010 and November 2012, 608 patients undergoing laparotomy were randomized at 16 centers across Germany. Three patients in the device group and 11 patients in the control group did not undergo laparotomy. Patients' and procedural characteristics were well balanced between the 2 groups. Forty-eight patients discontinued the study prematurely, mainly because of relaparotomy (control, n=9; intervention, n=9) and death (control, n=4; intervention, n=7). A total of 79 patients experienced SSIs within 30 days of surgery, 27 of 274 (9.9%) in the device group and 52 of 272 (19.1%) in the control group (odds ratio=0.462, 95% confidence interval: 0.281-0.762; P=0.002). Subgroup analyses indicate that the effect could be more pronounced in colorectal surgery, and in clean-contaminated/contaminated surgeries.

CONCLUSIONS

Our trial shows that CWEPs are effective at reducing the incidence of SSIs in elective and clean or clean-contaminated open abdominal surgery.

Wound edge protectors in open abdominal surgery to reduce surgical site infections: a systematic review and meta-analysis

Importance

Surgical site infections remain one of the most frequent complications following abdominal surgery and cause substantial costs, morbidity and mortality.

Objective

To assess the effectiveness of wound edge protectors in open abdominal surgery in reducing surgical site infections.

Evidence Review

A systematic literature search was conducted according to a prespecified review protocol in a variety of data-bases combined with hand-searches for randomized controlled trials on wound edge protectors in patients undergoing laparotomy. A qualitative and quantitative analysis of included trials was conducted.

Findings

We identified 16 randomized controlled trials including 3695 patients investigating wound edge protectors published between 1972 and 2014. Critical appraisal uncovered a number of methodological flaws, predominantly in the older trials. Wound edge protectors significantly reduced the rate of surgical site infections (risk ratio 0.65; 95%CI, 0.51–0.83; p = 0.0007; I² = 52%). The results were robust in a number of sensitivity analyses. A similar effect size was found in the subgroup of patients undergoing colorectal surgery (risk ratio 0.65; 95%CI, 0.44–0.97; p = 0.04; I² = 56%). Of the two common types of wound protectors double ring devices were found to exhibit a greater protective effect (risk ratio 0.29; 95%CI, 0.15–0.55) than single-ring devices (risk ratio 0.71; 95%CI, 0.54–0.92), but this might largely be due to the lower quality of available data for double-ring devices. Exploratory subgroup analyses for the degree of contamination showed a larger protective effect in contaminated cases (0.44; 95%CI, 0.28–0.67; p = 0.0002, I² = 23%) than in clean-contaminated surgeries (0.72, 95%CI, 0.57–0.91; p = 0.005; I² = 46%) and a strong effect on the reduction of superficial surgical site infections (risk ratio 0.45; 95%CI, 0.24–0.82; p = 0.001; I² = 72%).

Conclusions and Relevance

Wound edge protectors significantly reduce the rate of surgical site infections in open abdominal surgery. Further trials are needed to explore their effectiveness in different risk constellations.

Prevention of infectious complications after elective colorectal surgery in children: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee comprehensive review

OBJECTIVE

This goal of this review was to examine the clinical evidence in support of commonly utilized measures intended to reduce complications following elective colorectal surgery.

DATA SOURCE

Literature searches were performed to identify relevant studies from Medline, PubMed, and Cochrane databases.

STUDY SELECTION

The American Pediatric Surgery Association Outcomes and Clinical Trials Committee selected eight questions to address this topic systematically in the context of three management areas: 1) appropriate utilization of systemic antibiotics for colorectal procedures, 2) reduction of stool burden through mechanical bowel preparation, and 3) intraluminal gut decontamination through use of enteral nonabsorbable antibiotics. Primary outcomes of interest included the occurrence of infectious and mechanical complications related to stool burden and intraluminal bacterial concentration (incisional surgical site infection, anastomotic leakage, and intraabdominal abscess).

RESULTS

The evidence in support of each management category was systematically reviewed, graded, and summarized in the context of the review's primary outcomes. Practice recommendations were made as deemed appropriate by the committee.

CONCLUSIONS

Clinical evidence in support of interventions to reduce infectious complications following colorectal surgery is derived almost exclusively from the adult literature. High-quality evidence to guide clinical practice in children is sorely needed, as the available data may have only limited relevance to pediatric colorectal diseases.

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.

The prevention of surgical site infection in elective colon surgery

Infections at the surgical site continue to occur in as many as 20% of elective colon resection cases. Methods to reduce these infections are inconsistently applied. Surgical site infection (SSI) is the result of multiple interactive variables including the inoculum of bacteria that contaminate the site, the virulence of the contaminating microbes, and the local environment at the surgical site. These variables that promote infection are potentially offset by the effectiveness of the host defense. Reduction in the inoculum of bacteria is achieved by appropriate surgical site preparation, systemic preventive antibiotics, and use of mechanical bowel preparation in conjunction with the oral antibiotic bowel preparation. Intraoperative reduction of hematoma, necrotic tissue, foreign bodies, and tissue dead space will reduce infections. Enhancement of the host may be achieved by perioperative supplemental oxygenation, maintenance of normothermia, and glycemic control. These methods require additional research to identify optimum application. Uniform application of currently understood methods and continued research into new methods to reduce microbial contamination and enhancement of host responsiveness can lead to better outcomes.

Surgical site infections following colorectal cancer surgery: a randomized prospective trial comparing common and advanced antimicrobial dressing containing ionic silver

BACKGROUND

An antimicrobial dressing containing ionic silver was found effective in reducing surgical-site infection in a preliminary study of colorectal cancer elective surgery. We decided to test this finding in a randomized, double-blind trial.

METHODS

Adults undergoing elective colorectal cancer surgery at two university-affiliated hospitals were randomly assigned to have the surgical incision dressed with Aquacel Ag Hydrofiber dressing or a common dressing. To blind the patient and the nursing and medical staff to the nature of the dressing used, scrub nurses covered Aquacel Ag Hydrofiber with a common wound dressing in the experimental arm, whereas a double common dressing was applied to patients of control group. The primary end-point of the study was the occurrence of any surgical-site infection within 30 days of surgery.

RESULTS

A total of 112 patients (58 in the experimental arm and 54 in the control group) qualified for primary end-point analysis. The characteristics of the patient population and their surgical procedures were similar. The overall rate of surgical-site infection was lower in the experimental group (11.1% center 1, 17.5% center 2; overall 15.5%) than in controls (14.3% center 1, 24.2% center 2, overall 20.4%), but the observed difference was not statistically significant (P = 0.451), even with respect to surgical-site infection grade 1 (superficial) versus grades 2 and 3, or grade 1 and 2 versus grade 3.

CONCLUSIONS

This randomized trial did not confirm a statistically significant superiority of Aquacel Ag Hydrofiber dressing in reducing surgical-site infection after elective colorectal cancer surgery.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT00981110.

Standard abdominal wound edge protection with surgical dressings vs coverage with a sterile circular polyethylene drape for prevention of surgical site infections (BaFO): study protocol for a randomized controlled trial

Background

Postoperative surgical site infections cause substantial morbidity, prolonged hospitalization, costs and even mortality and remain one of the most frequent surgical complications. Approximately 14% to 30% of all patients undergoing elective open abdominal surgery are affected and methods to reduce surgical site infection rates warrant further investigation and evaluation in randomized controlled trials.

Methods/design

To investigate whether the application of a circular plastic wound protector reduces the rate of surgical site infections in general and visceral surgical patients that undergo midline or transverse laparotomy by 50%. BaFO is a randomized, controlled, patient-blinded and observer-blinded multicenter clinical trial with two parallel surgical groups. The primary outcome measure will be the rate of surgical site infections within 45 days postoperative assessed according to the definition of the Center for Disease Control. Statistical analysis of the primary endpoint will be based on the intention-to-treat population. The global level of significance is set at 5% (2 sided) and sample size (n = 258 per group) is determined to assure a power of 80% with a planned interim analysis for the primary endpoint after the inclusion of 340 patients.

Discussion

The BaFO trial will explore if the rate of surgical site infections can be reduced by a single, simple, inexpensive intervention in patients undergoing open elective abdominal surgery. Its pragmatic design guarantees high external validity and clinical relevance.

Trial registration

http://www.clinicaltrials.gov NCT01181206. Date of registration: 11 August 2010; date of first patient randomized: 8 September 2010

Is there a role for bowel preparation and oral or parenteral antibiotics in infection control in contemporary colon surgery?

The numbers of unanswered questions are many. Can intraoperative application, such as topical antimicrobial use in pulsed lavage, reduce the microbial burden on the wound interface before closure? Can closed suction drains within the closed surgical incision reduce infection rates, especially in patients with a large body mass index? What is the role of delayed primary closure or secondary closure in the wound where obvious contamination has occurred, or in the circumstance of emergent colonic resection where considerable contamination is encountered from preexistent perforation? Should immediate negative-pressure wound dressings be applied in the open contaminated wound? These and many other questions still confront the surgeon in the challenge of the surgical wound in major colorectal surgery.

Chlorhexidine-Alcohol versus Povidone-Iodine for Surgical-Site Antisepsis

BACKGROUND

Since the patient's skin is a major source of pathogens that cause surgical-site infection, optimization of preoperative skin antisepsis may decrease postoperative infections. We hypothesized that preoperative skin cleansing with chlorhexidine-alcohol is more protective against infection than is povidone-iodine.

METHODS

We randomly assigned adults undergoing clean-contaminated surgery in six hospitals to preoperative skin preparation with either chlorhexidine-alcohol scrub or povidone-iodine scrub and paint. The primary outcome was any surgical-site infection within 30 days after surgery. Secondary outcomes included individual types of surgical-site infections.

RESULTS

A total of 849 subjects (409 in the chlorhexidine-alcohol group and 440 in the povidone-iodine group) qualified for the intention-to-treat analysis. The overall rate of surgical-site infection was significantly lower in the chlorhexidine-alcohol group than in the povidone-iodine group (9.5% vs. 16.1%; P=0.004; relative risk, 0.59; 95% confidence interval, 0.41 to 0.85). Chlorhexidine-alcohol was significantly more protective than povidone-iodine against both superficial incisional infections (4.2% vs. 8.6%, P=0.008) and deep incisional infections (1% vs. 3%, P=0.05) but not against organ-space infections (4.4% vs. 4.5%). Similar results were observed in the per-protocol analysis of the 813 patients who remained in the study during the 30-day follow-up period. Adverse events were similar in the two study groups.

CONCLUSIONS

Preoperative cleansing of the patient's skin with chlorhexidine-alcohol is superior to cleansing with povidone-iodine for preventing surgical-site infection after clean-contaminated surgery. (ClinicalTrials.gov number, NCT00290290.)

Increased incidence of postoperative infections during prophylaxis with cephalothin compared to doxycycline in intestinal surgery

Background

The antibiotics used for prophylaxis during surgery may influence the rate of surgical site infections. Tetracyclines are attractive having a long half-life and few side effects when used in a single dose regimen. We studied the rate of surgical site infections during changing regimens of antibiotic prophylaxis in medium and major size surgery.

Methods

Prospective registration of surgical site infection following intestinal resections and hysterectomies was performed. Possible confounding procedure and patient related factors were registered. The study included 1541 procedures and 1489 controls. The registration included time periods when the regimen was changed from doxycycline to cephalothin and back again.

Results

The SSI in the colorectal department increased from 19% to 30% (p = 0.002) when doxycycline was substituted with cephalothin and decreased to 17% when we changed back to doxycycline (p = 0.005). In the gynaecology department the surgical site infection rate did not increase significantly. Subgroup analysis showed major changes in infections in rectal resections from 20% to 35% (p = 0.02) and back to 12% (p = 0.003).

Conclusion

Doxycycline combined with metronidazole, is an attractive candidate for antibiotic prophylaxis in medium and major size intestinal surgery.

Antimicrobial prophylaxis in colorectal surgery: focus on ertapenem

Despite improvement in infection control measures and surgical practice, surgical site infections (SSIs) remain a major cause of morbidity and mortality. In colorectal surgery, perioperative administration of a suitable antimicrobial regimen that covers both anaerobic and aerobic bacteria is universally accepted. In a prospective, double-blind, randomized study ertapenem was recently found to be more effective than cefotetan, a parenteral cephalosporin so broadly used as to be considered as gold standard in the prevention of SSIs following colorectal surgery. In this adequate and well controlled study, the superiority of ertapenem over cefotetan was clearly demonstrated from the clinical and bacteriological points of view. However, data that directly compares ertapenem with other antimicrobial regimen effective in preventing SSIs following colorectal surgery are lacking; furthermore, the possible risk of promotion of carbapenem resistance associated with widespread use of ertapenem prophylaxis as well as the ertapenem effects on the intestinal gut flora are of concern. Further comparative studies of ertapenem versus other widely used prophylactic regimens for colorectal surgery in patients submitted to mechanical bowel preparation versus no preparation as well as further research on adverse events of antibiotic prophylaxis, including emergence of resistance and Clostridium difficile infection, seem warranted.

Deep and organ/space infections in patients undergoing elective colorectal surgery: incidence and impact on hospital length of stay and costs

BACKGROUND

The reported incidence of infection complicating elective colorectal surgery (ECS) is 11% to 26%. We evaluated length of stay (LOS) and expense associated with such infections, which heretofore remain unexplored.

METHODS

We reviewed 1127 ECS procedures from October 2005 to may 2007 to identify infected case subjects (n = 46). Data were obtained by way of chart abstraction and administrative database review. A case-control study evaluated LOS and actual accounting costs for case subjects versus uninfected control subjects (n = 46). Logistic regression determined risk factors for infection.

RESULTS

Infection incidence was 4.1%. Mean +/- SD LOS and costs were greater for case than control subjects: 21 +/- 15 days compared with 6 +/- 4 days (P < .001) and $42,516 +/- 39,972 compared with $10,999 +/- $7,122 (P < .001). Procedure type, infection, chronic obstructive pulmonary disease, increased age, and nonsmoking status predicted greater LOS and costs. Infection risk factors included duration of procedure > or =3 hours, male sex, higher American Society of Anesthesiologists (ASA) score, low baseline hematocrit, and indication for surgery of regional enteritis/ulcerative colitis.

COMMENTS

Infection development after ECS is infrequent in our population, but it results in significantly poorer outcomes. Vigilant adherence to preventive guidelines, including those for antibiotic prophylaxis, is warranted.

Antimicrobial prophylaxis for colorectal surgery

BACKGROUND

Research shows that administration of prophylactic antibiotics before colorectal surgery prevents postoperative surgical wound infection (SWI). 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 SWI in patients undergoing colorectal surgery: specifically to determine, 1 Whether it reduces risk of SWI. 2 The target spectrum/a of bacteria (aerobic and/or anaerobic). 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.

SEARCH STRATEGY

CENTRAL, MEDLINE, and EMBASE, were searched from January, 1980 to December, 2007.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

Data were abstracted and reviewed by three authors for only the single, dichotomous outcome of SWI.

MAIN RESULTS

The review included 182 trials (30,880 participants), and 50 different antibiotics, including 17 cephalosporins. Many studies had multiple variables that separated the two study groups and could not be compared to other studies that tested one antibiotic and had a single variable separating the two groups. Meta-analyses demonstrated a statistically significant difference in postoperative SWI when prophylactic antibiotics were compared to placebo/no treatment (relative risk (RR) 0.30, 95% confidence intervals (CI) 0.22 to 0.41). No statistically significant differences were shown when comparing short- and long-term duration of prophylaxis (RR 1.06, 95% CI 0.89 to 1.27); or single dose versus multiple dose antibiotics (RR 1.17, 95% CI 0.67 to 2.05). Additional aerobic coverage and additional anaerobic coverage both showed statistically significant improvements in SWI rates (RR 0.41, 95% CI 0.23 to 0.71 and RR 0.55, 95% CI 0.35 to 0.85, respectively); as did combined oral and intravenous antibiotic prophylaxis when compared to intravenous alone (RR 0.55, 95% CI 0.41 to 0.74), or oral alone (RR 0.34, 95% CI 0.13 to 0.87). Established gold standard regimens were no less effective than any other antibiotic choice.

AUTHORS' CONCLUSIONS

Antibiotics covering aerobic and aerobic bacteria should be delivered orally and intravenously prior to colorectal surgery. Antibiotics delivered within this framework will reduce the risk of postoperative SWI by at least 75%. Further research is required to establish the optimal timing and duration of dosing, and frequency of longer-term adverse effects such as Clostridium difficile pseudomembranous colitis.

Polyethylene glycol versus sodium phosphate mechanical bowel preparation in elective colorectal surgery

BACKGROUND

The type of mechanical bowel preparation (MBP) used before elective colorectal surgery remains controversial.

METHODS

This post hoc analysis of a prospective randomized controlled antibiotic prophylaxis trial (ertapenem vs. cefotetan) evaluated the effect of polyethylene glycol (PEG) and sodium phosphate (SP) MBPs on the rates of postoperative surgical site infections (SSI).

RESULTS

Good to excellent MBPs were observed in 281 of 303 (93%) evaluable patients for the PEG and 336 of 367 (92%) for the SP types. A higher rate of SSI was observed in the PEG (34%) than SP (24%) group (difference, 10%; 95% confidence interval, 3.4-17.2). The MBP type was a significant risk factor for SSI, with SP favored over PEG (odds ratio, .6; 95% confidence interval, .43-.85) in univariate analysis; multivariate analysis favored SP, but was not significant (odds ratio, .69; 95% confidence interval, .46-1.02). SSI was lowest with SP and ertapenem (19%) and highest with PEG and cefotetan (44%).

CONCLUSIONS

SP, coupled with ertapenem antibiotic prophylaxis, may improve outcomes and reduce SSIs in patients undergoing elective colorectal surgery when compared with PEG coupled with cefotetan antibiotic prophylaxis.

Ertapenem versus cefotetan prophylaxis in elective colorectal surgery

BACKGROUND

Ertapenem, a long-acting carbapenem, may be an alternative to the recommended prophylactic antibiotic cefotetan.

METHODS

In this randomized, double-blind trial, we assessed the efficacy and safety of antibiotic prophylaxis with ertapenem, as compared with cefotetan, in patients undergoing elective colorectal surgery. A successful outcome was defined as the absence of surgical-site infection, anastomotic leakage, or antibiotic use 4 weeks postoperatively. All adverse events were collected until 14 days after the administration of antibiotic prophylaxis.

RESULTS

Of the 1002 patients randomly assigned to study groups, 901 (451 in the ertapenem group and 450 in the cefotetan group) qualified for the modified intention-to-treat analysis, and 672 (338 in the ertapenem group and 334 in the cefotetan group) were included in the per-protocol analysis. After adjustment for strata, in the modified intention-to-treat analysis, the rate of overall prophylactic failure was 40.2% in the ertapenem group and 50.9% in the cefotetan group (absolute difference, -10.7%; 95% confidence interval [CI], -17.1 to -4.2); in the per-protocol analysis, the failure rate was 28.0% in the ertapenem group and 42.8% in the cefotetan group (absolute difference, -14.8%; 95% CI, -21.9 to -7.5). Both analyses fulfilled statistical criteria for the superiority of ertapenem. In the modified intention-to-treat analysis, the most common reason for failure of prophylaxis in both groups was surgical-site infection: 17.1% in the ertapenem group and 26.2% in the cefotetan group (absolute difference, -9.1; 95% CI, -14.4 to -3.7). In the treated population, the overall incidence of Clostridium difficile infection was 1.7% in the ertapenem group and 0.6% in the cefotetan group (P=0.22).

CONCLUSIONS

Ertapenem is more effective than cefotetan in the prevention of surgical-site infection in patients undergoing elective colorectal surgery but may be associated with an increase in C. difficile infection. (ClinicalTrials.gov number, NCT00090272 [ClinicalTrials.gov].).

The prevention of wound infection in patients undergoing colorectal surgery

Colorectal operations are, at best, clean-contaminated procedures, and at times there is gross contamination of both the peritoneal cavity and the surfaces of the surgical wound. In addition, the diseases of the large bowel that require surgery tend to afflict elderly patients. Collectively, the combination of an unclean environment, major surgery and debilitated patients creates a situation that is associated with a very high incidence of wound infection. This review documents the considerable support from clinical trials and meta-analyses that exists for the prophylactic use of a single dose of a suitable parenteral antimicrobial agent. In addition, although the evidence is less clear cut, it does not appear that the use of mechanical bowel preparations reduces the incidence of wound infections after colorectal surgery.

The quality of measurement of surgical wound infection as the basis for monitoring: a systematic review

Comparison of postoperative surgical wound infection rates between institutions and over time is only valid if standard, valid and reliable definitions are used. The aim of this review was to assess evidence of validity and reliability of the definition and measurement of surgical wound infection. A systematic review was undertaken of prospective studies of surgical wound infection published over a seven-year period; 1993-1999. The information extracted from individual studies included: definition of surgical wound infection; details of wound assessment scale, scoring or grading scale systems; and evidence of assessment of validity, reliability and feasibility of identified definitions and grading systems. Two independent reviewers appraised 112 prospective studies, 90 of which were eligible for inclusion; eight studies assessed validity and/or reliability. Forty-one different definitions of surgical wound infection were identified, five of which were 'standard' definitions proposed by multi-disciplinary groups. Presence of pus was the most frequently used single component of any definition; the CDC definitions of 1988 and 1992 were the most widely implemented standard definitions; and the ASEPSIS wound assessment scale was the most frequently used quantitative grading tool. Only two formal validations of a definition were found, and six studies of reliability. This review highlights the extent of variation in definition of surgical wound infection used in clinical practice, and the need for validation of both content and organization of a surveillance system. However, realistically, there will have to be a balance between the quality of the measurement and the practicality of surveillance.

Septic complications of elective laparoscopic colorectal resection

BACKGROUND

We set out to determine the rate and pattern of septic complications of the surgical wound, abdominal cavity, and urinary and respiratory tracts following laparoscopic colorectal resection.

METHODS

A longitudinal database of 500 consecutive cases of colorectal resections was reviewed.

RESULTS

The total wound infection rate was 7.2% (36/500) and included infections of the abdominal wall wounds (32/500, 6.4%) and the perineal wounds (4/50, 8%). The anastomotic leak rate in 418 patients who underwent resection with primary anastomosis was 3.3% (14/418). Intraabdominal abscesses were diagnosed in 1% (5/500) of patients. Urinary tract infections were rare (3/500, 0.6%), as was postoperative pneumonia (6/500, 1%).

CONCLUSIONS

This study confirms the low rate of postoperative pneumonia observed with all other minimally invasive procedures. Intraabdominal abscesses, urinary tract infections, and postoperative pneumonia occur considerably less frequently than in reported historical controls for open surgery. The rates of abdominal wound infection and anastomotic leak in laparoscopic colorectal resection appear to be equivalent to traditional surgery, whereas the rate of perineal wound sepsis is lower. Comparative studies are needed to determine the differential costs of the septic episodes associated with the two approaches.

New Fluoroquinolones: Real and Potential Roles

The second-generation fluoroquinolones have enjoyed successful clinical use for more than 10 years in many countries, and they have a valued and proven record of safety and efficacy. However, deficiencies with respect to gram-positive and anaerobic organisms limit the use of these agents in respiratory, intra-abdominal, and pelvic infections. New, third-generation agents with dramatically increased activity against gram-positive and anaerobic bacteria--notably, Streptococcus pneumoniae and Bacteroides fragilis--have shown high rates of efficacy in pneumonia, bronchitis, and surgical and gynecologic infections. Although most of these new drugs produce similar clinical results, adverse reaction profiles differ and may influence therapeutic choices.

Safety and tolerability of intravenous-to-oral treatment and single-dose intravenous or oral prophylaxis with trovafloxacin

BACKGROUND

The new fourth-generation fluoroquinolone, trovafloxacin, is active in vitro against gram-positive and gram-negative organisms, atypical pathogens, and anaerobes, and has pharmacokinetics permitting once-daily intravenous or oral dosing. Safety/tolerability data from phase II/III clinical trials of sequential intravenous alatrofloxacin to oral trovafloxacin and single-dose intravenous or oral prophylaxis are summarized.

METHODS

All trials were double-blind, randomized, and multicenter. In multidose trials with alatrofloxacin, 1,257 patients requiring initial intravenous therapy received once-daily alatrofloxacin (trovafloxacin prodrug, 200 or 300 mg/day) followed by oral 200 mg/day trovafloxacin. An additional 444 patients received a single alatrofloxacin or trovafloxacin dose prophylactically for surgical procedures.

RESULTS

Therapy with alatrofloxacin was well tolerated. The most common treatment-related adverse events in studies of intravenous alatrofloxacin followed by oral trovafloxacin were nausea, headache, insertion site reaction, and dizziness. In single-dose intravenous or oral prophylaxis studies, insertion-site reaction, pruritus, and insertion-site pain were the most common treatment-related adverse events. No serious quinolone toxicity or drug interactions were reported. The incidence of serious treatment-related adverse events was < 1% in both the alatrofloxacin and comparator groups. In comparative trials, mortality due to all causes after trovafloxacin was similar to that after comparative agents; there was no mortality related to trovafloxacin administration.

CONCLUSION

In this large patient sample, intravenous alatrofloxacin followed by oral trovafloxacin was safe and well tolerated. Serious adverse events, such as phototoxicity, cardiovascular toxicity, and hemolytic anemia associated with older fluoroquinolones, were not noted with trovafloxacin. No interactions of trovafloxacin with other drugs were reported. The safety and tolerability of trovafloxacin, along with in vitro activity against key pathogens and pharmacokinetics permitting once-daily administration, support its oral and intravenous use in patients with obstetric, gynecologic, and intra-abdominal infections as well as for prophylaxis of surgical infection.