We longitudinally observed and assessed the impact of the operating room (OR) staff movements and door openings on surrogates of the exogenous infectious risk using a new technology system.

This multicenter observational study included 13 ORs from 10 hospitals, performing planned cardiac and orthopedic surgery (total hip or knee replacement). Door openings during the surgical procedure were obtained from data collected by inertial sensors fixed on the doors. Intraoperative staff movements were captured by a network of 8 infrared cameras. For each surgical procedure, 3 microbiological air counts, longitudinal particles counts, and 1 bacteriological sample of the wound before skin closure were performed. Statistics were performed using a linear mixed model for longitudinal data.

We included 34 orthopedic and 25 cardiac procedures. The median frequency of door openings from incision to closure was independently associated with an increased log10 0.3 µm particle (ß, 0.03; standard deviation [SD], 0.01; P = .01) and air microbial count (ß, 0.07; SD, 0.03; P = .03) but was not significantly correlated with the wound contamination before closure (r = 0.13; P = .32). The number of persons (ß, −0.08; SD, 0.03; P < .01), and the cumulated movements by the surgical team (ß, 0.0004; SD, 0.0005; P < .01) were associated with log10 0.3 µm particle counts.

This study has demonstrated a previously missing association between intraoperative staff movements and surrogates of the exogenous risk of surgical site infection. Restriction of staff movements and door openings should be considered for the control of the intraoperative exogenous infectious risk.

The best strategy for controlling extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) transmission in intensive care units (ICUs) remains elusive.

We developed a stochastic transmission model to quantify the effectiveness of interventions aimed at reducing the spread of ESBL-PE in an ICU.

We modeled the evolution of an outbreak caused by the admission of a single carrier in a 10-bed ICU free of ESBL-PE. Using data obtained from recent muticenter studies, we studied 26 strategies combining different levels of the following 3 interventions: (1) increasing healthcare worker compliance with hand hygiene before and after contact with a patient; (2) cohorting; (3) reducing antibiotic prevalence at admission with or without reducing antibiotherapy duration.

Improving hand hygiene compliance from 55% before patient contact and 60% after patient contact to 80% before and 80% after patient contact reduced the nosocomial incidence rate of ESBL-PE colonization by 91% at 90 days. Adding cohorting to hand hygiene improvement intervention decreased the proportion of ESBL-PE acquisitions by an additional 7%. Antibiotic restriction had the lowest impact on the epidemic. When combined with other interventions, it only marginally improved effectiveness, despite strong hypotheses regarding antibiotic impact on transmission.

Our results suggest that hand hygiene is the most effective intervention to control ESBL-PE transmission in an ICU.

Infect. Control Hosp. Epidemiol. 2016;37(3):272–280

Healthcare workers (HCWs), especially those caring for patients with tuberculosis (TB), are at high risk of acquiring that disease. The poor specificity of tuberculin skin testing (TST) prompted us to evaluate the effectiveness of the interferon-γ release assay (IGRA) in comparison with TST in a large prospective, multicenter, 1-year study of HCWs with occupational exposure to TB.

HCWs from high-risk units at 14 university hospitals were invited to participate and underwent both TST and IGRA (first Quantiferon TB Gold-IT®, QFT-G, then T-SPOT.TB® if QFT-G was indeterminate) at baseline and after 1 year. We collected demographic characteristics, country of birth, history of TB, immunosuppression, past exposure to TB, history of BCG vaccination, results of most recent TST, job category, and duration of current function.

Among 807 HCWs enrolled, current or past TST at baseline was positive (≥15 mm) in 282 (34.9%); the IGRA was positive in 113 (14.0%) and indeterminate in 3 (0.4%). After 1 year, 594 HCWs had both an IGRA and TST (or prior TST≥15 mm) at baseline and an IGRA and TST (if indicated). The conversion rate was 2.5% (9 of 367) with TST and 7.6% (45 of 594) with IGRA, with poor agreement between the 2 tests. Using only QFT-G, conversion (9.9%) and reversion (17.8%) rates were higher for baseline QFT-G positive quantitative values <1 IU/mL.

TST and the IGRA yielded discordant results. The value of IGRA in addition to TST remains undetermined; the two should be jointly interpreted in decision-making (clinical trial registration NCT00797836).

Infect Control Hosp Epidemiol 2015;00(0): 1–6

A systematic literature review was performed to assess the impact of surgical-staff behaviors on the risk of surgical site infections. Published data are limited, heterogeneous, and weakened by several methodological flaws, underlying the need for more studies with accurate tools.

To assess the current literature regarding the impact of surgical-staff behaviors on the risk of surgical-site infection (SSI).

Systematic literature review.

We searched the Medline, EMBASE, Ovid, Web of Science, and Cochrane databases for original articles about the impact of intraoperative behaviors on the risk of SSI published in English before September 2013.

We retrieved 27 original articles reporting data on number of people in the operating room (n=14), door openings (n=14; number [n=6], frequency [n=7], reasons [n=4], or duration [n=3]), surgical-team discipline (evidence of distraction; n=4), compliance with traffic measures (n=6), or simulated behaviors (n=3). Most (59%) articles were published in 2009–2013. End points were the 30-day SSI rate (n=8), air-particle count (n=2), or microbiological air counts (n=6); 11 studies were only descriptive. Number of people in the operating room and SSI rate or airborne contaminants (particle/bacteria) were correlated in 2 studies. Door openings and airborne bacteria counts were correlated in 2 observational studies and 1 experimental study. Two cohort studies showed a significant association between surgeon interruptions/distraction or noise and SSI rate. The level of evidence was low in all studies.

Published data about the impact of operating-room behaviors on the risk of infection are limited and heterogeneous. All studies exhibit major methodological flaws. More studies with accurate tools should be performed to address the influence of operating room behaviors on the infectious risk.

Infect Control Hosp Epidemiol 2015;36(1): 93–106

Antibiotic prescription is frequently inappropriate in hospitals. Our objective was to evaluate whether the quality of antibiotic prescription could be measured using case vignettes to assess physicians' knowledge.

The study was conducted in 2 public teaching hospitals, where 33/41 units and 206/412 physicians regularly prescribing antibiotics to inpatients agreed to participate. A cross-sectional survey of knowledge was performed using 4 randomly assigned case vignette sets. Curative antibiotic prescriptions were then evaluated using standard criteria for appropriateness at initiation (day 0), after 2–3 days of treatment (days 2–3), and at treatment completion. We compared knowledge of the physicians with their observed prescriptions in the subset of 106 physicians who completed the case vignettes and prescribed antibiotics at least once.

The median global case vignette score was 11.4/20 (interquartile range, 8.92-314.3). Of the 483 antibiotic prescriptions, 314 (65%) were deemed appropriate at day 0, 324 (72%) on days 2–3, and 227 (69%) at treatment completion. Prescriptions were appropriate at all 3 time points in only 43% of patients. Appropriate prescription was positively and independently associated with emergency prescription on day 0, documented infection on days 2–3, and 1 of the 2 hospitals at treatment completion. In addition, appropriateness at the 3 evaluation times was positively associated with prescription in anesthesiology or the intensive care unit. Case vignette scores above the median were significantly and independently associated with appropriate antibiotic prescription on days 2–3 and at treatment completion.

Case vignettes are effective for identifying physicians or hospitals whose knowledge and practice regarding antibiotic prescription require improvement.

To determine rates of colonization with multidrug-resistant (MDR) bacteria (ie, methicillin-resistant Staphylococcus aureus [MRSA], vancomycin-resistant Enterococcus [VRE], extended-spectrum β-lactamase [ESBL]-producing Enterobacteriaceae, and Acinetobacter baumannii) after prolonged hospitalization and to assess the yield of surveillance cultures and variables associated with colonization with MDR bacteria.

Prospective observational cohort study conducted from February 6 to May 26, 2006.

All patients who spent more than 30 days in our university hospital (Paris, France) were included. Rectal and nasal swab samples obtained during day 30 screening were examined for MRSA, VRE, ESBL-producing Enterobacteriaceae, and A. baumannii.

Of 470 eligible patients, 439 had surveillance culture samples available for analysis, including 51 patients (11.6%) with a history of colonization or infection due to 1 or more types of MDR bacteria (MRSA, recovered from 35 patients; ESBL-producing Enterobacteriaceae, from 16 patients; A. baumannii, from 6 patients; and VRE, from 0 patients) and 37 patients (9.5% of the 388 patients not known to have any of the 4 MDR bacteria before day 30 screening) newly identified as colonized by 1 or more MDR bacteria (MRSA, recovered from 20 patients; ESBL-producing Enterobacteriaceae, from 16 patients; A. baumannii, from 1 patient; and VRE, from 0 patients). A total of 87 (19.8%) of 439 patients were identified as colonized or infected with MDR bacteria at day 30. Factors that differed between patients with and without MRSA colonization included age, McCabe score, comorbidity score, receipt of surgery, and receipt of fluoroquinolone treatment. Patients with ESBL-producing Enterobacteriaceae colonization were younger than patients with MRSA colonization.

Differences in the variables associated with MRSA colonization and ESBL-producing Enterobacteriaceae colonization suggest differences in the epidemiology of these 2 organisms. Day 30 screening resulted in a 72.5% increase in the number of patients identified as colonized with at least 1 type of MDR bacteria.

Femoral neck fracture is the most frequent orthopedic emergency among elderly persons. Despite a high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage in this population, no multicenter study of antibiotic prophylaxis practices and the rate and microbiological characteristics of surgical site infection (SSI) has been performed in France.

Retrospective, multicenter cohort study.

Twenty-two university and community hospitals in France.

Each center provided data on 25 consecutive patients who underwent surgery for femoral neck fracture during the first quarter of 2005. Demographic, clinical, and follow-up characteristics were recorded, and most patients had a follow-up office visit or were involved in a telephone survey 1 year after surgery.

These 22 centers provided data on 541 patients, 396 (73%) of whom were followed up 1 year after surgery. Of 504 (93%) patients for whom antibiotic prophylaxis was recorded, 433 (86%) received a cephalosporin. Twenty-two patients had an SSI, for a rate of 5.6% (95% confidence interval, 3.7-8.0). SSI was reported for 15 (6.9%) of patients who had a prosthesis placed and for 7 (3.9%) who underwent osteosynthesis (P = .27). SSI was diagnosed a median of 30 days after surgery (interquartile range, 21-41 days); 7 (32%) of these SSIs were superficial infections, and 15 (68%) were deep or organ-space infections. MRSA caused 7 SSIs (32%), Pseudomonas aeruginosa caused 5 (23%), other staphylococci caused 4 (18%), and other bacteria caused 2 (9%); the etiologic pathogen was unknown in 4 cases (18%). Reoperation was performed for 14 patients with deep or organ-space SSI, including 6 of 7 patients with MRSA SSI. The mortality rate 1 year after surgery was 20% overall but 50% among patients with SSI. In univariate analysis, only the National Nosocomial Infections Surveillance System risk index score was significantly associated with SSI (P = .006).

SSI after surgery for femoral neck fracture is severe, and MRSA is the most frequently encountered etiologic pathogen. A large, multicenter prospective trial is necessary to determine whether the use of antibiotic prophylaxis effective against MRSA would decrease the SSI rate in this population.

Despite contact isolation precautions for patients with methicillin-resistant Staphylococcus aureus (MRSA), MRSA infections are increasing in many countries.

To evaluate the role of a potential unrecognized reservoir of MRSA carried by patients in acute care wards, we determined the prevalence of MRSA at hospital admission, with special emphasis on screening-specimen yields.

A 1,100-bed teaching hospital in Paris, France.

Nasal screening cultures were performed at admission to a tertiary-care teaching hospital for patients older than 75 years.

MRSA was isolated from 63 (7.9%) of 797 patients. On the multivariate analysis, variables significantly associated with MRSA carriage were presence of chronic skin lesions (adjusted odds ratio [AOR], 5.10; 95% confidence interval [CI95], 2.52–10.33); transfer from a nursing home, rehabilitation unit, or long-term-care unit (AOR, 4.52; CI95, 2.23–9.18); and poor chronic health status (AOR, 1.80; CI95, 1.02–3.18). Without admission screening, 84.1% of MRSA carriers would have been missed at hospital admission and 76.2% during their hospital stay. Furthermore, 81.1% of days at risk for MRSA dissemination would have been spent without contact isolation precautions had admission screening not been performed.

MRSA carriage at hospital admission is far more prevalent than MRSA-positive clinical specimens. This may contribute to failure of contact isolation programs. Screening cultures at admission help to identify the reservoir of unknown MRSA patients.

To describe an outbreak of imipenem-resistant Acinetobacter baumannii (IR-Ab) and the measures for its control, and to investigate risk factors for IR-Ab acquisition.

An observational and a case-control study.

A surgical intensive care unit (ICU) in a university tertiary care hospital.

After admission to the ICU of an IR-Ab-positive patient, patients were prospectively screened for IR-Ab carriage upon admission and then once a week. Environmental cleaning and barrier safety measures were used for IR-Ab carriers. A case-control study was performed to identify factors associated with IR-Ab acquisition. Cases were patients who acquired IR-Ab. Controls were patients who were hospitalized in the ICU at the same time as cases and were exposed to IR-Ab for a similar duration as cases. The following variables were investigated as potential risk factors: baseline characteristics, scores for severity of illness and therapeutic intervention, presence and duration of invasive procedures, and antimicrobial administration.

Beginning in May 1996, the outbreak involved 17 patients over 9 months, of whom 12 acquired IR-Ab (cases), 4 had IR-Ab isolates on admission to the ICU, and 1 could not be classified. Genotypic analysis identified two different IR-Ab isolates, responsible for three clusters. Ten of the 12 nosocomial cases developed infection. Control measures included reinforcement of barrier safety measures, limitation of the number of admissions, and thorough environmental cleaning. No new case was identified after January 1997. Eleven of the 12 cases could be compared to 19 controls. After adjustment for severity of illness, a high individual therapeutic intervention score appeared to be a risk factor for IR-Ab acquisition.

The outbreak ended after strict application of control measures. Our results suggest that high work load contributes to IR-Ab acquisition.