Epidemiological Surveillance of Surgical Site Infection and its Risk Factors in Cardiac Surgery: A Prospective Cohort Study

Risk Factors for Postoperative Infections in Cardiac Surgery Patients: A Retrospective Study

Background and objective Cardiac surgery is one of the most common surgical procedures globally; its incidence has been on the rise due to the faster pace of population aging thanks to technological and epidemiological advances. Patients who undergo cardiac surgeries may face various postoperative complications that might affect their survival, and one of these major complications is infection. Nosocomial pneumonia, surgical site infection (SSI), mediastinitis, bacteremia, and sepsis are common infections encountered after surgeries. In this study, we aimed to determine the common risk factors related to postoperative infections at the King Faisal Cardiac Center from January 2014 to September 2020. Materials and methods  Records from 364 patients who underwent cardiac surgery and were aged above 18 years were assessed for postoperative infections in this retrospective cohort study. Patients who were immunosuppressed or had active systemic infections were excluded. Consent was waived by the Institutional Review Board. All procedures were performed at the King Faisal Cardiac Center, National Guard Hospital, Jeddah. Results Of the total 364 patients, 105 were women and 259 were men. The mean age of the cohort was 59 years (SD = 13) and the mean BMI was 29.1 kg/m2 (SD = 5.3). The study population showed a high prevalence of cardiac risk factors and diseases: diabetes (n = 244, 67%), hypertension (n = 230, 63%), dyslipidemia (n = 144, 40%), smoking (n = 80, 22%), heart failure (n = 41, 11%), and chronic obstructive pulmonary disease (n = 6, 1.6%). The overall rate of postoperative infection was 32.7% (n = 120), and 17 (14%) of these infected patients underwent reoperations for infection. Conclusion Based on a thorough analysis of 364 patients undergoing various cardiac surgical procedures, including a multivariate analysis accounting for preoperative factors, there was a significant association between postoperative infections and hypertension, diabetes, increased preoperative activated partial thromboplastin time, and elevated HbA1c.

Intranasal Mupirocin to Reduce Surgical Site Infection Post Cardiac Surgery: A Review of the Literature

Sternal wound infections after cardiac surgery are associated with high rates of morbidity and mortality. One of the known risk factors of sternal wound infection is Staphylococcus aureus colonisation. Intranasal mupirocin decolonisation therapy implemented pre-operatively appears to be an effective preventative measure in reducing sternal wound infections post-cardiac surgery. Therefore, the main aim of this review is to evaluate the current literature regarding the use of intranasal mupirocin before cardiac surgery and its impact on sternal wound infection rates.

Evaluation of Postoperative Development of Saphenous Vein Graft Incision Site Infections in Patients Undergoing Isolated Coronary Artery Bypass Graft Surgery: A Single Center Experience

Objective: This study aimed to evaluate surgical site infection patients developing saphenous vein graft incision site infection after isolated coronary artery bypass graft surgery performed in the cardiovascular surgery clinic of our hospital in the last 12 years to reveal the causative microorganisms, risk factors, and clinical characteristics. Material and Methods: A total of 34 surgical site infection patients (23 females, 11 males; mean age 68.0±9.0 years; range 51-86 years) who underwent isolated coronary artery bypass graft surgery in the cardiovascular surgery clinic of our hospital between March 2009 and November 2020 and who postoperatively developed saphenous vein graft incision site infection were included in the study. The patients' demographic data, underlying diseases, and preoperative, intraoperative, and postoperative risk factors were analyzed retrospectively. Results: In all isolated coronary artery bypass graft surgeries performed over a period of about 12 years, the rate of saphenous vein graft incision site surgical site infection was found to be 0.8%. Of these, 23 (67.6%) were evaluated as superficial incisional surgical site infection and 11 (32.4%) as deep incisional surgical site infection. In the patients who developed surgical site infection, the parameters of age, female sex, obesity, diabetes mellitus, smoking, emergency surgery, use of more than 1 saphenous vein graft, prolonged operation, cardiopulmonary bypass, and aortic clamp durations, intraoperative blood transfusion, length of stay in the intensive care unit, use of inotropes, and total length of hospital stay were all found to be significant. The microorganisms in purulent discharge cultures consisted of Gram-negative bacteria in 18 (53%), Gram-positive bacteria in 12 (35.3%), and fungi in 1 (2.9%). No pathogenic microorganism growth was observed in 5 (14.7%) patients. In the patients with surgical site infection, coagulase-negative staphylococci (17.6%) and Escherichia coli (17.6%) were the most frequently isolated agents. Conclusion: Particular attention should be paid to surgical site infection in patients undergoing a cardiovascular surgery intervention. It should be noted that post coronary artery bypass graft surgery surgical site infection can be reduced by determining its risk factors, modifying surgical techniques, and postoperative close monitoring of patients. Follow-up and personal care are crucial after discharge and an empirical treatment approach should be determined when an infection occurs, taking into account that coagulase-negative staphylococci and E. coli were the two leading infectious agents in our hospital.

Estimated Costs Associated with Surgical Site Infections in Patients Undergoing Cholecystectomy

Among healthcare-associated infections, surgical site infections (SSIs) are the most frequent in Spain. The aim of this work was to estimate the costs of SSIs in patients who underwent a cholecystectomy at the Hospital General Universitario de Alicante (Spain) between 2012-2017. This was a prospective observational cohort study. The Active Epidemiological Surveillance Program at our hospital recorded all the cholecystectomies performed. Risk factors associated with the development of SSIs were determined by multivariate analysis and two homogeneous comparison groups were obtained by using the propensity score. The number of extra days of hospital stay were recorded for patients with an SSI and with the cost per hospitalised day data, the additional cost attributed to SSIs was calculated. A total of 2200 cholecystectomies were considered; 110 patients (5.0%) developed an SSI. The average length of hospital stay was 5.6 days longer among patients with an SSI. The cost per SSI was EUR 1890.60 per patient, with the total cost for this period being EUR 207,961.60. SSIs after cholecystectomy lead to a prolongation of hospital stay and an increase in economic costs. It is essential to implement infection surveillance and control programs to reduce SSIs, improve patient safety, and reduce economic burden.

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.

Impact of Pre-operative Hemoglobin A1C Level and Microbiological Pattern on Surgical Site Infection After Cardiac Surgery

Background Surgical site infection (SSI) after cardiac surgery is a major concern. A limited number of studies have addressed the relationship of preoperative glycemic control on the risk of developing SSI after cardiac surgery. We aim to determine the incidence, microbiological pattern, and impact of preoperative hemoglobin A1C (Hgb A1C) on the development of SSI after cardiac surgery. Methods This is a single-center retrospective chart review that was performed on adult patients undergoing cardiac surgery from January 2017 to December 2018. Results Two hundred and twenty-nine patients underwent 233 procedures. The median age was 60 years; 71% males, 64% were diabetic, and 67% had a Hb A1C above 7% preoperatively. Around 7% of patients developed deep SSI. For patients that developed SSI, 63% had gram-negative bacteria. Hb A1C >7% was not found to be associated with an increased incidence of SSI. Conclusion Our results show that there is no apparent relationship between pre-operative Hgb A1C levels and SSI after cardiac surgery. Although we follow a comprehensive SSI perioperative bundle based on international guidelines that advocates using antibiotics to cover gram-positive organisms, it is interesting that the rate of gram-negative organisms in our patients' cohort is unexpectedly high. We believe that adjusting the perioperative antibiotic regimen based on local microbiological patterns seems to be a reasonable and easily achievable target to decrease the incidence of SSI.

Risk factors of nosocomial infection after cardiac surgery in children with congenital heart disease

Background

The aim of our study was to analyze the risk factors of nosocomial infection after cardiac surgery in children with congenital heart disease (CHD).

Methods

We performed a retrospective cohort study, and children with CHD who underwent open-heart surgeries at Shanghai Children’s Medical Center from January 1, 2012 to December 31, 2018 were included. The baseline characteristics of these patients of different ages, including neonates (0–1 months old), infants (1–12 months old) and children (1–10 years old), were analyzed, and the association of risk factors with postoperative nosocomial infection were assessed.

Results

A total of 11,651 subjects were included in the study. The overall nosocomial infection rate was 10.8%. Nosocomial infection rates in neonates, infants, and children with congenital heart disease were 32.9, 15.4, and 5.2%, respectively. Multivariate logistic regression analysis found age (OR 0798, 95%CI: 0.769–0.829; P < 0.001), STS risk grade (OR 1.267, 95%CI: 1.159–1.385; P < 0.001), body mass index (BMI) <5th percentile (OR 1.295, 95%CI: 1.023–1.639; P = 0.032), BMI >95th percentile (OR 0.792, 95%CI: 0.647–0.969; P = 0.023), cardiopulmonary bypass (CPB) time (OR 1.008, 95%CI: 1.003–1.012; P < 0.001) and aortic clamping time (OR 1.009, 1.002–1.015; P = 0.008) were significantly associated with nosocomial infection in CHD infants. After adjusted for confounding factors, we found STS risk grade (OR 1.38, 95%CI: 1.167–1.633; P < 0.001), BMI < 5th percentile (OR 1.934, 95%CI: 1.377–2.715; P < 0.001), CPB time (OR 1.018, 95%CI: 1.015–1.022; P < 0.001), lymphocyte/WBC ratio<cut off value (OR 3.818, 95%CI: 1.529–9.533; P = 0.004) and AST>cut off value (OR 1.546, 95%CI: 1.119–2.136; P = 0.008) were significantly associated with nosocomial infection in CHD children.

Conclusion

Our study suggested STS risk grade, BMI, CPB duration, low lymphocyte/WBC or high neutrophil/WBC ratio were independently associated with nosocomial infection in CHD infant and children after cardiac surgery.

Comparison of olanexidine versus povidone-iodine for preventing surgical site infection in gastrointestinal surgery: study protocol for a multicentre, single-blind, randomised controlled clinical trial

INTRODUCTION

The prevalence of surgical site infection (SSI) remains higher in gastrointestinal surgery than in other surgeries. Although several guidelines have indicated the efficacy of chlorhexidine and povidone-iodine in reducing the SSI rate, the optimal recommendation has still not been established. Therefore, it is necessary to determine the more effective antiseptic for surgical site preparation. Olanexidine (1.5% olanedine, Otsuka Pharmaceutical Factory, Tokushima, Japan), which is a new antiseptic in Japan, has antimicrobial activity against a wide range of bacteria, including Gram-positive and Gram-negative bacteria. Our study will contribute to determining a new antiseptic for use in gastrointestinal and other surgeries.

METHODS AND ANALYSIS

We propose a multicentre, randomised controlled clinical trial for comparing two treatments, that is, 1.5% olanexidine or 10% povidone-iodine, for surgical skin preparation to prevent SSI in clean-contaminated gastrointestinal surgeries with surgical wounds. Patients aged ≥20 years at the time of consent will be included. The primary outcome measure is the 30-day postoperative SSI rate. For the primary analysis, which is aimed at comparing the treatment effects, the adjusted risk ratio and its 95% CI will be estimated using the Mantel-Haenszel method.

ETHICS AND DISSEMINATION

The protocol was first approved by the Institutional Review Board of Keio University School of Medicine, followed by the institutional review board of each participating site. Participant recruitment began in June 2018. The final results will be published in international peer-reviewed medical journals.

TRIAL REGISTRATION NUMBER

UMIN 000031560; Pre-results.

A New Surgical Site Infection Risk Score: Infection Risk Index in Cardiac Surgery

Various scoring systems attempt to predict the risk of surgical site infection (SSI) after cardiac surgery, but their discrimination is limited. Our aim was to analyze all SSI risk factors in both coronary artery bypass graft (CABG) and valve replacement patients in order to create a new SSI risk score for such individuals. A priori prospective collected data on patients that underwent cardiac surgery (n = 2020) were analyzed following recommendations from the Reporting of studies Conducted using Observational Routinely collected health Data (RECORD) group. Study participants were divided into two periods: the training sample for defining the new tool (2010–2014, n = 1298), and the test sample for its validation (2015–2017, n = 722). In logistic regression, two preoperative variables were significantly associated with SSI (odds ratio (OR) and 95% confidence interval (CI)): diabetes, 3.3/2–5.7; and obesity, 4.5/2.2–9.3. The new score was constructed using a summation system for punctuation using integer numbers, that is, by assigning one point to the presence of either diabetes or obesity. The tool performed better in terms of assessing SSI risk in the test sample (area under the Receiver-Operating Characteristic curve (aROC) and 95% CI, 0.67/055–0.76) compared to the National Nosocomial Infections Surveillance (NNIS) risk index (0.61/0.50–0.71) and the Australian Clinical Risk Index (ACRI) (0.61/0.50–0.72). A new two-variable score to preoperative SSI risk stratification of cardiac surgery patients, named Infection Risk Index in Cardiac surgery (IRIC), which outperforms other classical scores, is now available to surgeons. Personalization of treatment for cardiac surgery patients is needed.

Ability to predict the development of surgical site infection in cardiac surgery using the Australian Clinical Risk Index versus the National Nosocomial Infections Surveillance-derived Risk Index

Surgical site infection (SSI) is a major infectious complication that increases mortality, morbidity, and healthcare costs. There are scores attempting to classify patients for calculating SSI risk. Our objectives were to validate the Australian Clinical Risk Index (ACRI) in a European population after cardiac surgery, comparing it against the National Nosocomial Infections Surveillance-derived risk index (NNIS) and analyzing the predictive power of ACRI for SSI in valvular patients. All the patients that who underwent cardiac surgery in a tertiary university hospital between 2011 and 2015 were analyzed. The patients were divided into valvular and coronary groups, excluding mixed patients. The ACRI score was validated in both groups and its ability to predict SSI was compared to the NNIS risk index. We analyzed 1,657 procedures. In the valvular patient group (n: 1119), a correlation between the ACRI score and SSI development (p < 0.05) was found; there was no such correlation with the NNIS index. The area under the receiver-operating characteristic curve (AUC) was 0.64 (confidence interval [CI] 95%, 0.5-0.7) for ACRI and 0.62 (95% CI, 0.5-0.7) for NNIS. In the coronary group (n: 281), there was a correlation between ACRI and SSI but no between NNIS and SSI. The ACRI AUC was 0.70 (95% CI, 0.5-0.8) and the NNIS AUC was 0.60 (95% CI, 0.4-0.7). The ACRI score has insufficient predictive power, although it predicts SSI development better than the NNIS index, fundamentally in coronary artery bypass grafting (CABG). Further studies analyzing determining factors are needed.