Thirteen-year experience with universal Staphylococcus aureus nasal decolonization prior to cardiac surgery: a quasi-experimental study.

INTRODUCTION: Sternal wound infection (SWI) after cardiac surgery is a severe complication. Among preventive measures, pre-operative decolonization of nasal carriage of Staphylococcus aureus has recently been shown to be beneficial. This quasi-experimental study assessed the effect of decolonization on the incidence of S. aureus-associated SWI based on 19 years of prospective surveillance. METHODS: Segmented negative binomial regression was used to analyse the change over time in the incidence of S. aureus mediastinitis requiring re-operation after cardiac surgery in a French university hospital between 1996 and 2014. Universal nasal decolonization with mupirocin was introduced in December 2001. The association between pre-operative nasal carriage and SWI due to S. aureus was analysed between 2006 and 2012. RESULTS: Among 17,261 patients who underwent a cardiac surgical procedure, 565 developed SWI (3.3%), which was caused by S. aureus in 181 cases (1%). The incidence of mediastinitis caused by S. aureus decreased significantly over the study period (1.43% in 1996-2001 vs 0.61% and 0.64% in 2002-2005 and 2006-2014, respectively; P<0.001). In segmented analysis, there was a significant break in 2002, corresponding to the introduction of decolonization. Despite this intervention, pre-operative nasal carriage remained a significant risk factor for S. aureus mediastinitis (adjusted odds ratio 2.2; 95% confidence interval 1.2-4.2), as were obesity, critical pre-operative status, coronary artery bypass grafting (CABG), and combined surgery with valve replacement and CABG. CONCLUSION: Universal nasal decolonization before cardiac surgery was effective in decreasing the incidence of mediastinitis caused by S. aureus. Nasal carriage of S. aureus remained a risk factor for S. aureus-associated SWI.

Surgical site infection with extended-spectrum ß-lactamase-producing Enterobacteriaceae after cardiac surgery: incidence and risk factors.

OBJECTIVE: To determine the incidence, microbiology and risk factors for sternal wound infection (SWI) with extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) following cardiac surgery. METHODS: We performed a retrospective analysis between January 2006 and December 2015 of prospective surveillance of a cohort of patients with cardiac surgery at a single centre (Paris, France). SWI was defined as the need for reoperation due to sternal infection. All patients with an initial surgery under extracorporeal circulation and diagnosed with an SWI caused by Enterobacteriaceae isolates were included. We compared patients infected with at least one ESBL-PE with those with SWI due to other Enterobacteriaceae by logistic regression analysis. RESULTS: Of the 11 167 patients who underwent cardiac surgery, 412 (3.7%) developed SWI, among which Enterobacteriaceae were isolated in 150 patients (36.5%), including 29 ESBL-PE. The main Enterobacteriaceae (n = 171) were Escherichia coli in 49 patients (29%) and Enterobacter cloacae in 26 (15%). Risk factors for SWI with ESBL-PE in the multivariate logistic regression were previous intensive care unit admission during the preceding 6 months (adjusted odds ratio (aOR) 12.2; 95% CI 3.3-44.8), postoperative intensive care unit stay before surgery for SWI longer than 5 days (aOR 4.6; 95% CI 1.7-11.9) and being born outside France (aOR 3.2; 95% CI 1.2-8.3). CONCLUSIONS: Our results suggest that SWI due to ESBL-PE was associated with preoperative and postoperative unstable state, requiring an intensive care unit stay longer than the usual 24 or 48 postoperative hours, whereas being born outside France may indicate ESBL-PE carriage before hospital admission.

Eclipsed mitral regurgitation: an unusual cause of acute heart failure.

AIMS: So far, a total of five patients with eclipsed mitral regurgitation (MR) have been reported in the literature by three different teams. The aim of this article was to detail clinical and echocardiographic characteristics, and outcome of patients presenting eclipsed MR. METHODS AND RESULTS: We defined eclipsed MR as spontaneous appearance, at rest, from 1 min to the next of an acute restriction in the motion of mitral leaflets preventing coaptation and leading to massive MR in patients with normal left ventricular end-diastolic diameter, left ventricular ejection fraction >45%, and baseline MR ≤2. Spontaneous regression occurred within 30 min, and no obvious trigger such as acute hypertension, new-onset arrhythmia, or myocardial ischaemia is present. Clinical data, ECG, echocardiographic data, surgery report, and follow-up status of six patients with eclipsed MR are reported: all were post-menopausal women with median age of 74 [57-80] years presenting hypertension (4/6), chronic kidney disease (5/6), or chronic anaemia (4/6). Five out of six patients experienced acute pulmonary oedema requiring hospitalization and underwent mitral valve replacement because of heart failure recurrence. Two patients died in the first days after surgery while the three others are free of symptoms at, respectively, 56, 18, and 10 months follow-up. CONCLUSION: Eclipsed MR is a clinical and echocardiographic syndrome responsible for heart failure with preserved EF. It is presently underdiagnosed and should be evoked in cases of recurrent acute pulmonary oedema without obvious trigger, in particular in patients presenting discordant evaluation of MR severity over time.

Efficacy of intraoperative dexmedetomidine compared with placebo for surgery in adults: a meta-analysis of published studies.

Dexmedetomidine (Dex) demonstrates sedative and analgesic effects. We investigated the intraoperative and postoperative effects of intraoperative Dex administration during surgery in adult patients. A search for randomized placebo-controlled trials was conducted in Pubmed and Embase databases to identify randomized controlled clinical trials using intraoperative Dex for surgery in adult population. Outcome assessed were: intraoperative and postoperative opioid consumption, time of recovery from anesthesia, postoperative pain, and postoperative nausea or vomiting (PONV) in the first 24 hours. Data from each trial were combined to calculate pooled odds ratios (OR), mean difference (MD) or standardized mean difference (SMD) and 95% confidence interval (95 % CI). Heterogeneity was measured using I² statistics. Eighteen randomized controlled trials were analyzed. Dex was administered to 815 patients and 410 received placebo. Overall, Dex significantly decreased intraoperative opioid consumption (SMD=-1.58 [-2.98, -0.19], I²=95 %, P<0.00001), but did not decrease time of recovery from anesthesia (SMD=-0.13 [-1.60, 1.34] minutes, I²=95 %, P<0.00001). Dex significantly reduced postoperative opioid consumption (SMD=-1.58 [-2.98, -0.19], I²=95 %, P<0.00001), postoperative pain intensity (SMD=-0.73 [-1.19, -0.27], I²=62 %, P=0.03), and the prevalence of PONV (OR=0.43 [0.27, 0.69], I²=0 %, P=0.46). This meta-analysis shows that intraoperative Dex administration in adult patients reduces intra and postoperative opioid consumption, postoperative pain and PONV. Time of recovery is not affected.

Sternal wound infection after cardiac surgery: incidence and risk factors according to clinical presentation.

The incidence of surgical site infection (SSI) after cardiac surgery depends on the definition used. A distinction is generally made between mediastinitis, as defined by the US Centers for Disease Control and Prevention (CDC), and superficial SSI. Our objective was to decipher these entities in terms of presentation and risk factors. We performed a 7-year single centre analysis of prospective surveillance of patients with cardiac surgery via median sternotomy. SSI was defined as the need for reoperation due to infection. Among 7170 patients, 292 (4.1%) developed SSI, including 145 CDC-defined mediastinitis (CDC-positive SSI, 2.0%) and 147 superficial SSI without associated bloodstream infection (CDC-negative SSI, 2.1%). Median time to reoperation for CDC-negative SSI was 18 days (interquartile range, 14-26) and 16 (interquartile range, 11-24) for CDC-positive SSI (p 0.02). Microorganisms associated with CDC-negative SSI were mainly skin commensals (62/147, 41%) or originated in the digestive tract (62/147, 42%); only six were due to Staphylococcus aureus (4%), while CDC-positive SSI were mostly due to S. aureus (52/145, 36%) and germs from the digestive tract (52/145, 36%). Risk factors for SSI were older age, obesity, chronic obstructive bronchopneumonia, diabetes mellitus, critical preoperative state, postoperative vasopressive support, transfusion or prolonged ventilation and coronary artery bypass grafting, especially if using both internal thoracic arteries in female patients. The number of internal thoracic arteries used and factors affecting wound healing were primarily associated with CDC-negative SSI, whereas comorbidities and perioperative complications were mainly associated with CDC-positive SSI. These 2 entities differed in time to revision surgery, bacteriology and risk factors, suggesting a differing pathophysiology.

Performance and impact of a rapid method combining mass spectrometry and direct antimicrobial susceptibility testing on treatment adequacy of patients with ventilator-associated pneumonia.

Inappropriate antibiotic therapy in ventilator-associated pneumonia (VAP) is associated with increased mortality. Using broad-spectrum antibiotics for 48 h until the results of conventional cultures and antimicrobial susceptibility testing (AST) are available, may promote the emergence of drug-resistant bacteria. Performing AST directly on clinical respiratory samples would hasten the process by at least 24 h. Here, we analysed the diagnostic performance of a rapid method combining mass spectrometry and direct AST (DAST), and compared it with the conventional method (mass spectrometry with conventional AST (CAST)). Additionally, we assessed its potential impact on antimicrobial use in patients. Over a period of 18 months, the two methods were performed on 85 bronchoalveolar lavages obtained from intensive care unit patients with suspected VAP, and in which Gram-negative bacilli were observed on direct examination. Only the CAST results were reported to the clinicians. DAST produced useable results in 85.9% of the patients. The sensitivity and negative predictive values of DAST were 100% for all antibiotics tested, except gentamicin (97.1%, (95% CI 93.3-101) and 97.4% (93.7-101), respectively) and amikacin (88.9% (81.7-96.1) and 96.4% (92.1-100.7), respectively), compared with CAST. Specificity and positive predictive values ranged from 82.9 (74.2-91.5) to 100%, and from 86.4 (78.5-94.2) to 100%, respectively. If the DAST results had been reported to the clinicians, treatment could have been optimized 24 h earlier in 35/85 (41.2%) patients, with 17 carbapenem patient-days saved. Overall, routine use of the DAST method could help optimize earlier antibiotic treatment in patients with suspected VAP.

Utility of cardiac troponin measurement after cardiac surgery.

Postoperative cardiac failure due to myocardial necrosis remains a major complication in cardiac surgical procedures and its diagnosis is still difficult. In fact, cardiac enzymes, electrocardiogram and echographic signs are often misleading. The prognostic valve of troponin I after coronary artery bypass or conventional value surgery has been evaluated in 500 adult patients. Postoperative troponin I concentrations after cardiac surgery represent an independent variable associated with mortality (in-hospital death) and morbidity (low cardiac output and acute renal failure).