Different duration strategies of perioperative antibiotic prophylaxis in adult patients undergoing cardiac surgery: an observational study

Prevention of infection in aortic or aortoiliac peripheral arterial reconstruction

BACKGROUND

Peripheral arterial disease (PAD) results from the narrowing of arteries. Aortic aneurysms - abnormal dilatations in artery walls - are a related concern. For severe cases, arterial reconstruction surgery is the treatment option. Surgical site infections (SSIs) are a feared and common complication of vascular surgery. These infections have a significant global healthcare impact. Evaluating the effectiveness of preventive measures is essential.

OBJECTIVES

To assess the effects of pharmacological and non-pharmacological interventions, including antimicrobial therapy, antisepsis, and wound management, for the prevention of infection in people undergoing any open or hybrid aortic or aortoiliac peripheral arterial reconstruction.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases, and the World Health Organization International Clinical Trials Registry Platform, LILACS, and ClinicalTrials.gov up to 11 November 2024.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) with a parallel (e.g. cluster or individual) or split-body design, and quasi-RCTs, which assessed any intervention to reduce or prevent infection following aortic or aortoiliac procedures for the treatment of aneurysm or PAD. There were no limitations regarding age and sex.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently extracted the data and assessed the risk of bias of the trials. A third review author resolved disagreements when necessary. We assessed the evidence certainty for key outcomes using GRADE.

MAIN RESULTS

We included 21 RCTs with 4952 participants. Fifteen studies were assessed as having a high risk of bias in at least one domain, and 19 studies had an unclear risk of bias in at least one domain. We analysed 10 different comparisons for eight different outcomes. The comparisons were antibiotic versus placebo or no treatment; short-duration antibiotics (≤ 24 hours) versus long-duration antibiotics (> 24 hours); different types of systemic antibiotics (one versus another); antibiotic-bonded implant versus standard implant; Dacron graft versus stretch polytetrafluoroethylene graft; prophylactic closed suction drainage versus undrained wound; individualised goal-directed therapy (IGDT) versus fluid therapy based on losses, standard haemodynamic parameters and arterial blood gas values (standard care); comprehensive geriatric assessment versus standard preoperative care; percutaneous versus open-access technique; and negative pressure wound therapy (NPWT) versus standard dressing. The primary outcomes were graft infection rate and SSI rate. The secondary outcomes included all-cause mortality, arterial reconstruction failure rate, re-intervention rate, amputation rate, pain resulting from the intervention, and adverse events resulting from the interventions to prevent infection. We did not assess all the outcomes across the different comparisons. The main findings are presented below. Antibiotic versus placebo or no treatment (five studies) Very low-certainty evidence from five included studies suggests that antibiotic prophylaxis reduces SSI (risk ratio (RR) 0.33, 95% confidence interval (CI) 0.15 to 0.71; 5 studies, 583 participants; number needed to treat for an additional beneficial outcome (NNT) 9). With very low- to low-certainty evidence, there was little or no difference between the groups in the other assessed outcomes (graft infection rate, all-cause mortality, re-intervention rate, and amputation rate). We did not quantitatively assess other outcomes in this comparison. Short duration antibiotics (≤ 24 hours) versus long duration antibiotics (> 24 hours) (three studies) Very low-certainty evidence from three included studies suggests that there is little or no difference in graft infection rate (RR 2.74, 95% CI 0.11 to 65.59; 1 study, 88 participants) or SSI rate (RR 3.65, 95% CI 0.59 to 7.71; 1 study, 88 participants) between short- and long-duration antibiotic prophylaxis. We did not quantitatively assess other outcomes in this comparison. Different types of systemic antibiotics (one versus another) (seven studies) We grouped seven studies comparing one antibiotic to another into three subgroups that compared different classes of antibiotics amongst themselves. We found little or no difference between the groups analysed. Graft infection rate: beta-lactams versus cephalosporins (RR 0.36, 95% CI 0.02 to 8.71; 1 study, 88 participants; very low-certainty evidence); glycopeptides versus cephalosporins (RR 5.00, 95% CI 0.24 to 103.05; 1 study, 238 participants; low-certainty evidence); one cephalosporin versus another (RR not estimable, CI not estimable; 1 study; 69 participants; very low-certainty evidence); SSI rate: beta-lactams and cephalosporins (RR 0.27, 95% CI 0.03 to 2.53; 2 studies, 229 participants; very low-certainty evidence); glycopeptides versus cephalosporins (RR 2.17, 95% CI 0.65 to 7.23; 2 studies, 312 participants; very low-certainty evidence); and one cephalosporin versus another (RR 1.26, 95% CI 0.21 to 7.45; 3 studies, 625 participants; very low-certainty evidence). We could extract all-cause mortality data for the glycopeptide versus cephalosporin comparison; there was little or no difference between groups (RR 1.33, 95% CI 0.30 to 5.83; 1 study, 238 participants; low-certainty evidence). We did not quantitatively assess other outcomes in this comparison.

AUTHORS' CONCLUSIONS

Very low-certainty evidence suggests that the use of prophylactic antibiotics may prevent SSIs in aortic or aortoiliac peripheral arterial reconstruction. We found no superiority amongst specific antibiotics or differences in extended antibiotic use (over 24 hours) compared with shorter use (up to 24 hours), with low-certainty evidence. For other interventions, very low- to moderate-certainty evidence showed little or no difference across various outcomes. We advise interpreting these conclusions with caution due to the limited number of events in all groups and comparisons.

Effect of an E-Prescription Intervention on the Adherence to Surgical Chemoprophylaxis Duration in Cardiac Surgery: A Single Centre Experience

In our hospital, adherence to the guidelines for peri-operative antimicrobial prophylaxis (PAP) is suboptimal, with overly long courses being common. This practice does not offer any incremental benefit, and it only adds to the burden of antimicrobial consumption, promotes the emergence of antimicrobial resistance, and it is associated with adverse events. Our objective was to study the effect of an electronic reminder on the adherence to each element of PAP after cardiac surgery. We conducted a single center, before and after intervention, prospective cohort study from 1 June 2014 to 30 September 2017. The intervention consisted of a reminder of the hospital guidelines when ordering PAP through the hospital information system. The primary outcome was adherence to the suggested duration of PAP, while secondary outcomes included adherence to the other elements of PAP and incidence of surgical site infections (SSI). We have studied 1080 operations (400 pre-intervention and 680 post-intervention). Adherence to the appropriate duration of PAP increased significantly after the intervention [PRE 4.0% (16/399) vs. POST 15.4% (105/680), chi-square p < 0.001]; however, it remained inappropriately low. Factors associated with inappropriate duration of PAP were pre-operative hospitalization for <3 days, and duration of operation >4 h, while there were significant differences between the chief surgeons. Unexpectedly, the rate of SSIs increased significantly during the study (PRE 2.8% (11/400) vs. POST 5.9% (40/680), chi-square p < 0.019). The implemented intervention achieved a relative increase in adherence to the guideline-recommended PAP duration; however, adherence was still unacceptably low and further efforts to improve adherence are needed.

Assessment of the impact of intravenous antibiotics treatment on gut microbiota in patients: Clinical data from pre-and post-cardiac surgery

Background and aims

Surgical site infection is a common complication after surgery. Periprocedural antibiotics are necessary to prescribe for preventing or treating infections. The present study aimed to explore the effect of intravenous antibiotics on gut microbiota and menaquinone biosynthesis in patients, especially in elderly patients undergoing cardiac surgery.

Methods

A total of 388 fecal samples were collected from 154 cardiac surgery patients. The V3-V4 hypervariable region of the bacterial 16S rRNA gene was amplified and sequenced on a MiSeq PE300. The gut microbiota diversity of samples was analyzed in terms of α- and β-diversity at the OTU level. The different groups were classified according to antibiotics in combinations and single antibiotics. PICRUSt2 was used for preliminary prediction of the gut microbiota function for menaquinone biosynthesis.

Results

The intravenously administered antibiotics which are excreted via bile represents the main antibiotics that could disturb the gut microbiota's composition in cardiac surgery patients, especially for elderly patients. The effect of antibiotics on gut microbiota is produced after antibiotics treatments over one week. The recovery of gut microbiota to the state of pre-antibiotics may require over two weeks of antibiotics withdrawal. Sex factor doesn't represent as an influencer in gut microbiota composition. Long-term use of cefoperazone-sulbactam may affect coagulation function.

Conclusions

The composition of the gut microbiota had a significant change post-intravenous antibiotics treatment in cardiac surgery patients. The richness and diversity of gut microbiota are increased in elderly patients.

Surgical Site Infection in Cardiac Surgery

Surgical site infections (SSIs) are one of the most significant complications in surgical patients and are strongly associated with poorer prognosis. Due to their aggressive character, cardiac surgical procedures carry a particular high risk of postoperative infection, with infection incidence rates ranging from a reported 3.5% and 26.8% in cardiac surgery patients. Given the specific nature of cardiac surgical procedures, sternal wound and graft harvesting site infections are the most common SSIs. Undoubtedly, DSWIs, including mediastinitis, in cardiac surgery patients remain a significant clinical problem as they are associated with increased hospital stay, substantial medical costs and high mortality, ranging from 3% to 20%. In SSI prevention, it is important to implement procedures reducing preoperative risk factors, such as: obesity, hypoalbuminemia, abnormal glucose levels, smoking and S. aureus carriage. For decolonisation of S. aureus carriers prior to cardiac surgery, it is recommended to administer nasal mupirocin, together with baths using chlorhexidine-based agents. Perioperative management also involves antibiotic prophylaxis, surgical site preparation, topical antibiotic administration and the maintenance of normal glucose levels. SSI treatment involves surgical intervention, NPWT application and antibiotic therapy.

The value of prophylactic antibiotics in coronary artery bypass graft surgery: A review of literature

Infections have a significant impact on increasing both the morbidity and mortality rate of patients who have undergone coronary artery bypass graft (CABG) surgery. Infection after CABG imposes a clinical and economic burden on patients and health care organizations; therefore, prevention should be on the agenda. This review will focus on the value of using prophylactic antibiotics in coronary artery bypass graft surgery (CABG). Prophylactic antibiotics like cephalosporin and vancomycin are more commonly used antibiotics and are strongly associated with reduced infection risk in patients. The results showed that using antibiotics during the perioperative period and after CABG is an effective strategy for reducing post-infection problems without compromising the patients' clinical outcomes. Diabetic patients are prone to postoperative infection after CABG, however, prophylactic antibiotics should not be the only strategy used to reduce the risk of postoperative infection in diabetic patients. Perioperative glycaemic control is essential for diabetic patients undergoing CABG. Appropriate antibiotic prophylaxis has a great impact on preventing infection after CABG but duration and selecting appropriate antibiotic is important. Standardizing the use of antibiotic prophylaxis reduces the rate of infection and unwanted bacterial resistance, which could subsequently reduce economic costs to patients and public health.

Gut Microbiota as Early Predictor of Infectious Complications before Cardiac Surgery: A Prospective Pilot Study

Cardiac surgery remains a field of medicine with a high percentage of postoperative complications, including infectious ones. Modern data indicate a close relationship of infectious disorders with pathological changes in the composition of the gut microbiome; however, the extent of such changes in cardiac surgery patients is not fully clarified. In this prospective, observational, single center, pilot study, 72 patients were included, 12 among them with the infectious complications. We analyzed the features of the fecal microbiota before and in the early postoperative period, as one of the markers for predicting the occurrence of bacterial infection. We also discovered the significant change in microbial composition in the group of patients with infectious complications compared to the non-infectious group before and after cardiac surgery, despite the intra-individual variation in composition of gut microbiome. Our study demonstrated that the group of patients that had a bacterial infection in the early postoperative period already had an altered microbial composition even before the surgery. Further studies will evaluate the clinical significance of the identified proportions of individual taxa of the intestinal microbiota and consider the microbiota as a novel target for reducing the risk of infectious complications.

Pharmacodynamic Evaluation of a Single Dose versus a 24-Hour Course of Multiple Doses of Cefazolin for Surgical Prophylaxis

The optimal perioperative duration for the administration of cefazolin and other prophylactic antibiotics remains unclear. This study aimed to describe the pharmacodynamics of cefazolin for a single 2 g dose versus a 24 h course of a 2 g single dose plus a 1 g eight-hourly regimen against methicillin-susceptible Staphylococcus aureus. Static concentration time-kill assay and a dynamic in vitro hollow-fibre infection model simulating humanised plasma and interstitial fluid exposures of cefazolin were used to characterise the pharmacodynamics of prophylactic cefazolin regimens against methicillin-sensitive Staphylococcus aureus clinical isolates. The initial inoculum was 1 × 105 CFU/mL to mimic a high skin flora inoculum. The static time-kill study showed that increasing the cefazolin concentration above 1 mg/L (the MIC) did not increase the rate or the extent of bacterial killing. In the dynamic hollow-fibre model, both dosing regimens achieved similar bacterial killing (~3-log CFU/mL within 24 h). A single 2 g dose may be adequate when low bacterial burdens (~104 CFU/mL) are anticipated in an immunocompetent patient with normal pharmacokinetics.

Antimicrobial prophylaxis in adult cardiac surgery in the United Kingdom and Republic of Ireland

BACKGROUND

Deep sternal wound infections are a financially costly complication of cardiac surgery with serious implications for patient morbidity and mortality. Prophylactic antimicrobials have been shown to reduce the incidence of infection significantly. In 2018, the European Association for CardioThoracic Surgery (EACTS) provided clear guidance advising that third-generation cephalosporins are the first-line prophylactic antimicrobial of choice for cardiac surgery via median sternotomy as a result of their broad spectrum of activity and association with reduced postoperative mortality. Despite this guidance, it was believed that UK practice differed from this as a consequence of national concerns surrounding cephalosporins use and Clostridioides difficile infection.

METHODS

A survey was developed and distributed to all UK and Republic of Ireland (ROI) cardiac surgery centres in January 2019 to quantify this variation.

RESULTS

Of the 38 centres, 34 responded. Variation existed between the antimicrobial agent used, as well as the dosage, frequency and duration of suggested regimens even among centres using the same antimicrobial agent. The most common antimicrobial prophylaxis prescribed was a combination of flucloxacillin and gentamicin (16, 47%). Followed by cefuroxime (6, 17.6%) and cefuroxime combined with a glycopeptide (4, 11.7%). In patients colonised with methicillin-resistant Staphylococcus aureus or those with penicillin allergy gentamicin combined with teicoplanin was most common (42% and 50%, respectively).

DISCUSSION

This variation in antimicrobial agents and regimens may well contribute to the varying incidence of surgical site infection seen across the UK and ROI.

Surgical site infections: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of post-operative surgical site infections (SSIs) in solid organ transplantation. SSIs are a significant cause of morbidity and mortality in SOT recipients. Depending on the organ transplanted, SSIs occur in 3%-53% of patients, with the highest rates observed in small bowel/multivisceral, liver, and pancreas transplant recipients. These infections are classified by increasing invasiveness as superficial incisional, deep incisional, or organ/space SSIs. The spectrum of organisms implicated in SSIs in SOT recipients is more diverse than the general population due to other important factors such as the underlying end-stage organ failure, immunosuppression, prolonged hospitalizations, organ transportation/preservation, and previous exposures to antibiotics in donors and recipients that could predispose to infections with multidrug-resistant organisms. In this guideline, we describe the epidemiology, clinical presentation, differential diagnosis, potential pathogens, and management. We also provide recommendations for the selection, dosing, and duration of peri-operative antibiotic prophylaxis to minimize post-operative SSIs.

Steroids in cardiac surgery trial: a substudy of surgical site infections

PURPOSE

Postoperative infection, particularly in cardiac surgery, results in significant morbidity, mortality, and healthcare cost. Identification of novel predictors of postoperative infection can target high-risk populations for prophylactic intervention.

METHODS

Steroids in cardiac surgery (SIRS) was a multi-centre randomized-controlled trial assessing intraoperative administration of methylprednisone during cardiac surgery, which enrolled 7,507 patients across 80 centres in 18 countries. It demonstrated that administration of steroids had no effect on mortality or major morbidity after cardiac surgery. Our primary objective was to identify risk factors for postoperative surgical site infections using SIRS participants as a cohort. We excluded patients who did not undergo surgery, died intraoperatively, or died within 48 hr of the operation. Patients were assessed for development of "surgical site infection" over the first 30 days postoperatively. Using theoretical and previously identified risk factors, we used forward stepwise entry to create a binary logistic regression model.

RESULTS

Follow-up at 30 days was complete for all patients; 7,406 were included in the cohort. Surgical site infection occurred in 180 (4.8%) and 184 (5.0%) of patients in the placebo and steroid arms respectively. Significant risk factors (P < 0.05 level) included: diabetes managed with insulin (adjusted odds ratio [aOR]: 1.55; 95% confidence interval [CI] 1.13 to 2.12), oral hypoglycemics (aOR 1.60; 95% CI 1.18 to 2.16), or diet (aOR 1.81; 95% CI 1.16 to 2.83), female sex (aOR 1.34; 95% CI 1.05 to 1.71), renal failure with (aOR 2.03; 95% CI 1.06 to 3.91), and without (aOR 1.50; 95% CI 1.04 to 2.14) dialysis, > 96 min cardiopulmonary bypass (CPB) time (aOR 1.84; 95% CI 1.44 to 2.35), body mass index (BMI) < 22.3 (aOR 0.44; 95% CI 0.28 to 0.71) or > 30 (aOR 1.49; 95% CI 1.17 to 1.89), peak intensive care unit blood glucose (aOR 1.02 per mmol·L^-1; 95% CI 1.00 to 1.04), and coronary artery bypass grafting (CABG) operation type (aOR 2.59; 95% CI 1.87 to 3.59).

CONCLUSIONS

Patients undergoing CABG, requiring longer CPB, with higher BMI, or with diabetes, are at elevated risk of surgical site infection. Strategies to mitigate this risk warrant further investigation.

Prevention of deep sternal wound infection in cardiac surgery: a literature review

BACKGROUND

Deep sternal wound infection (DSWI) is a dreaded complication of cardiac surgery with considerable consequences in terms of mortality, morbidity and treatment costs. In addition to standard surgical site infection prevention guidelines, multiple specific measures in the prevention of DSWI have been developed and evaluated in the past decades. This review focuses on these specific measures to prevent DSWI.

METHODS

An extensive literature search was performed to assess interventions in the prevention of DSWI. Articles describing results of a randomized controlled trial were categorized by type of intervention. Results were yielded and, if possible, pooled.

RESULTS

From a total of 743 articles found, 48 randomized controlled trials were selected. Studies were divided into 12 categories, containing pre-, peri- and postoperative preventive measures. Specific measures shown to be effective were: antibiotic prophylaxis with a first-generation cephalosporin for at least 24 h, application of local gentamicin before chest closure, sternal closure with figure-of-eight steel wires, and postoperative chest support using a corset or vest.

CONCLUSION

This study identified several measures that prevent DSWI after cardiac surgery that are not frequently applied in current practice. It is recommended that the guidelines on prevention of surgical site infection in cardiac surgery should be updated.