A novel method of assessing for lung sliding using Doppler imaging.

Ultrasound is an ideal modality in the emergency department (ED) to assess for pneumothorax given its rapid availability, portability, and repeatability to assess clinical status changes. Certain patient populations and clinical circumstances may present challenges to the performance of this examination. In this article, we review patterns of the presence or absence of lung sliding in the commonly utilized sonographic modes in the ED setting. We also describe a novel technique to evaluate lung sliding using tissue Doppler.

Risk factors for bloodstream infection caused by extended-spectrum ß-lactamase-producing Escherichia coli and Klebsiella pneumoniae: A focus on antimicrobials including cefepime.

BACKGROUND: Extended-spectrum ß-lactamase (ESBL)-producing pathogens represent increasing challenges to physicians because of rising prevalence, high mortality, and challenging treatment. Identifying high risks and early appropriate therapy is critical to favorable outcomes. METHODS: This is a 5-year retrospective case-case-control study performed at the Detroit Medical Center on adult patients with bloodstream infection (BSI) caused by ESBL-producing and non-ESBL-producing Escherichia coli or Klebsiella pneumoniae, each compared with uninfected controls. Data were collected from December 2004-August 2009. Multivariate analysis was performed using logistic regression. RESULTS: Participants included 103 patients with BSI caused by ESBL-producing pathogens and 79 patients with BSI caused by pathogens that did not produce ESBLs. The mean age of patients in the ESBL group was 67 years; of the patients, 51% were men, 77% were black, and 38% (n = 39) died in hospital. The mean age of patients in the non-ESBL group was 58 years; of the patients, 51% were men, 92% were black, and 22% (n = 17) died in hospital. On multivariate analysis, predictors of BSI caused by ESBL-producing pathogens included central venous catheter (odds ratio [OR], 29.4; 95% confidence interval [CI], 3.0-288.3), prior ß-lactam-/ß-lactamase-inhibitor therapy (OR, 28.1; 95% CI, 1.99-396.5), and prior cefepime therapy (OR, 22.7; 95% CI, 2.7-192.4). The only risk factor for BSI caused by non-ESBL-producing pathogens was urinary catheter insertion (OR, 18.2; 95% CI, 3.3-100.3). CONCLUSION: Prior antimicrobial therapy, particularly with ß-lactam, was the strongest unique risk factor for BSI caused by ESBL-producing E coli or K pneumoniae.

Emergency department ultrasound probe infection control: challenges and solutions.

Point-of-care ultrasound (US) has become a cornerstone in the diagnosis and treatment of patients in the emergency department (ED). Despite the beneficial impact on patient care, concern exists over repeat use of probes and the role as a vector for pathogen transmission. US probes are used for various applications, with the level of infection risk, based on the Spaulding Classification, ranging from noncritical with common practice to semicritical with endocavitary probes. To date, the most closely studied organisms are Staphylococcus aureus and human papilloma virus. Current evidence does confirm probe colonization but has not established a causative role in human infection. Based on current literature, US use during invasive procedures remains an infection control concern, but routine use on intact skin does not appear to cause significant risk to patients. Various barrier methods are available, each with indications based on extent of procedure and likelihood of contact with mucosal surfaces. Additionally, chemical cleansing methods have been shown to be effective in limiting probe contamination after use. New technologies utilizing ultraviolet light are available and effective but not widely used in the ED setting. As our understanding of the critical factors in US probe cleaning and disinfection improves, it is important to assess the challenges found in our current practice and to identify potential solutions to improve practices and procedures in infection control across the spectrum of US probe use in various applications in the ED. This article serves as a summary of the current literature available on infection control topics with the utilization of point-of-care US, and discusses challenges and potential solutions to improve the current practice of probe-related infection control.

Effectiveness and cost of implementing an active surveillance screening policy for Acinetobacter baumannii: a Monte Carlo simulation model.

BACKGROUND: Acinetobacter baumannii infections are common and associated with high mortality and costs. Early identification of asymptomatic carriers can reduce patient-to-patient transmission, but the sensitivity of A baumannii surveillance tools is poor, and thus active surveillance is not routine practice. This study examined whether an active surveillance screening policy can reduce the transmission, mortality, and costs associated with A baumannii. METHODS: A simulation model was developed to determine the impact of active screening on patient outcomes. Model parameters included A baumannii prevalence, screening sensitivity and specificity, probability of transmission, progression from colonization to infection, mortality, and cost of screening, contact precautions, and infection. A scenario analysis was performed to evaluate the robustness of the results when varying the sensitivity of the screening test and the prevalence rate of A baumannii. RESULTS: Assuming a screening sensitivity of 55%, active screening reduced A baumannii transmissions, infections, and deaths by 48%. As the screening sensitivity approached 90%, the reduction in transmissions, infections, and deaths reached 78%. For all scenarios tested, active surveillance was cost saving (19%-53% reduction in mean hospital cost per patient) except at a carrier prevalence of ≤2% and screening test sensitivity of ≤55%. CONCLUSIONS: In institutions where A baumannii is endemic or during epidemics, implementing a surveillance program is cost-saving and can greatly reduce transmissions and deaths. Methodologies to improve the sensitivity of surveillance testing will help optimize the clinical impact of active screening programs on preventing the spread of A baumannii in health care facilities.

Contact precautions: more is not necessarily better.

OBJECTIVE: To determine whether increases in contact isolation precautions are associated with decreased adherence to isolation practices among healthcare workers (HCWs). DESIGN: Prospective cohort study from February 2009 to October 2009. SETTING: Eleven teaching hospitals. PARTICIPANTS: HCWs. METHODS: One thousand thirteen observations conducted on HCWs. Additional data included the number of persons in isolation, types of HCWs, and hospital-specific contact precaution practices. Main outcome measures included compliance with individual components of contact isolation precautions (hand hygiene before and after patient encounter, donning of gown and glove upon entering a patient room, and doffing upon exiting) and overall compliance (all 5 measures together) during varying burdens of isolation. RESULTS: Compliance with hand hygiene was as follows: prior to donning gowns/gloves, 37.2%; gowning, 74.3%; gloving, 80.1%; doffing of gowns/gloves, 80.1%; after gown/glove removal, 61%. Compliance with all components was 28.9%. As the burden of isolation increased (20% or less to greater than 60%), a decrease in compliance with hand hygiene (43.6%-4.9%) and with all 5 components (31.5%-6.5%) was observed. In multivariable analysis, there was an increase in noncompliance with all 5 components of the contact isolation precautions bundle (odds ratio [OR], 6.6 [95% confidence interval (CI), 1.15-37.44]; P = .03) and in noncompliance with hand hygiene prior to donning gowns and gloves (OR, 10.1 [95% CI, 1.84-55.54]; P = .008) associated with increasing burden of isolation. CONCLUSIONS: As the proportion of patients in contact isolation increases, compliance with contact isolation precautions decreases. Placing 40% of patients under contact precautions represents a tipping point for noncompliance with contact isolation precautions measures.

Surgical site infections in genital reconstruction surgery for gender reassignment, Detroit: 1984-2008.

BACKGROUND: Gender reassignment surgery (i.e., male-to-female or female-to-male) entails a series of complex surgical procedures. We conducted a study to explore epidemiologic characteristics of patients who underwent genital reconstruction operations as components of gender reassignment and to analyze risk factors for surgical-site infections (SSIs) following these operations. METHODS: The study was a retrospective cohort study conducted from 1984-2008 at Harper University Hospital, a tertiary hospital with 625 beds in Detroit, Michigan. Surgical site infection was defined according to established criteria. RESULTS: Records were available for 82 patients who underwent a total of 1,383 operations as part of genital-reconstruction processes. Thirty-nine (47.6%) of the patients underwent female-to-male reassignment (FTM) and 43 (52.4%) underwent male-to-female reassignment (MTF). The average age of the study cohort was 39.5±9.8 y. Of the patients in the cohort, 56 (68.3%) were Caucasian and 67 (81.7%) were single. The average number of operative encounters per patient was 11.8±4.6 for FTM and 4.9±2.4 for MTF. Forty-three (52.4%) patients developed an SSI at least once during their genital reconstruction process, of whom 34 (87%) were in the FTM group and nine (21%) in the MTF group (p<0.001). Staphylococci were the most common pathogens (61%) isolated in these infections, followed by Enterobacteriaceae (50%), Enterococcus (39%), and Pseudomonas aeruginosa (33.3%). Surgical site infection was associated independently with an increased frequency of operative procedures and operating room encounters. CONCLUSIONS: More than 50% of patients who underwent genital reconstruction operations developed an SSI at some point during the genital reconstruction process. Surgical site infections are more common in FTM than in MTF reconstruction operations, and for both FTM and MTF, SSIs are associated independently with an increased frequency of total operative procedures and encounters.

Epidemiology of bloodstream infections caused by Acinetobacter baumannii and impact of drug resistance to both carbapenems and ampicillin-sulbactam on clinical outcomes.

Acinetobacter baumannii has become a leading cause of bloodstream infections (BSI) in health care settings. Although the incidence of infection with carbapenem- and ampicillin-sulbactam-resistant (CASR) A. baumannii has increased, there is a scarcity of studies which investigate BSI caused by CASR A. baumannii. A retrospective cohort study was conducted on adult patients with BSI caused by A. baumannii and who were admitted to the Detroit Medical Center between January 2006 and April 2009. Medical records were queried for patients' demographics, antimicrobial exposures, comorbidities, hospital stay, and clinical outcomes. Bivariate analyses and logistic regression were employed in the study. Two hundred seventy-four patients with BSI caused by A. baumannii were included in the study: 68 (25%) caused by CASR A. baumannii and 206 (75%) caused by non-CASR A. baumannii. In multivariate analysis, factors associated with BSI caused by CASR A. baumannii included admission with a rapidly fatal condition (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 1.27 to 6.32, P value = 0.01) and prior use of antimicrobials (OR = 2.83, 95% CI = 1.18 to 6.78, P value = 0.02). In-hospital mortality rates for BSI caused by CASR A. baumannii were significantly higher than those for non-CASR A. baumannii-induced BSI (43% versus 20%; OR = 3.0, 95% CI = 1.60 to 5.23, P value < 0.001). However, after adjusting for potential confounders, the association between BSI caused by CASR A. baumannii and increased risk of in-hospital mortality was not significant (OR = 1.15, 95% CI = 0.51 to 2.63, P value = 0.74). This study demonstrated that CASR A. baumannii had a distinct epidemiology compared to more susceptible A. baumannii strains; however, clinical outcomes were similar for the two groups. Admission with a rapidly fatal condition was an independent predictor for both CASR A. baumannii and in-hospital mortality.

The carbapenem-resistant Enterobacteriaceae score: a bedside score to rule out infection with carbapenem-resistant Enterobacteriaceae among hospitalized patients.

Patients infected with carbapenem-resistant Enterobacteriaceae often experience delays in initiation of appropriate antimicrobial therapy and increased mortality. A score was developed to differentiate bloodstream infections caused by carbapenem-resistant Enterobacteriaceae (16 patients) versus extended-spectrum ß-lactamase-producing Enterobacteriaceae (166 patients). A score of ≥ 32 demonstrated high area under the curve of 0.80 (95% confidence interval: 0.68-0.92) and a negative predictive value of 97%.

Impact of cefepime therapy on mortality among patients with bloodstream infections caused by extended-spectrum-ß-lactamase-producing Klebsiella pneumoniae and Escherichia coli.

Extended-spectrum-ß-lactamase (ESBL)-producing pathogens are associated with extensive morbidity and mortality and rising health care costs. Scant data exist on the impact of antimicrobial therapy on clinical outcomes in patients with ESBL bloodstream infections (BSI), and no large studies have examined the impact of cefepime therapy. A retrospective 3-year study was performed at the Detroit Medical Center on adult patients with BSI due to ESBL-producing Klebsiella pneumoniae or Escherichia coli. Data were collected from the medical records of study patients at five hospitals between January 2005 and December 2007. Multivariate analysis was performed using logistic regression. One hundred forty-five patients with BSI due to ESBL-producing pathogens, including K. pneumoniae (83%) and E. coli (16.5%), were studied. The mean age of the patients was 66 years. Fifty-one percent of the patients were female, and 79.3% were African-American. Fifty-three patients (37%) died in the hospital, and 92 survived to discharge. In bivariate analysis, the variables associated with mortality (P < 0.05) were presence of a rapidly fatal condition at the time of admission, use of gentamicin as a consolidative therapeutic agent, and presence of one or more of the following prior to culture date: mechanical ventilation, stay in the intensive care unit (ICU), and presence of a central venous catheter. In multivariate analysis, the predictors of in-hospital mortality included stay in the intensive care unit (odds ratio [OR], 2.17; 95% confidence interval [CI], 0.98 to 4.78), presence of a central-line catheter prior to positive culture (OR, 2.33; 95% CI, 0.77 to 7.03), presence of a rapidly fatal condition at the time of admission (OR, 5.13; 95% CI, 2.13 to 12.39), and recent prior hospitalization (OR, 1.92; 95% CI, 0.83 to 4.09). When carbapenems were added as empirical therapy to the predictor model, there was a trend between empirical carbapenem therapy and decreased mortality (OR, 0.61; 95% CI, 0.26 to 1.50). When added to the model, receipt of empirical cefepime alone (n = 43) was associated with increased mortality, although this association did not reach statistical significance (OR, 1.66; 95% CI, 0.71 to 3.87). The median length of hospital stay was shorter for patients receiving empirical cefepime than for those receiving empirical or consolidated carbapenem therapy. In multivariate analysis, empirical therapy with cefepime for BSI due to an ESBL-producing pathogen was associated with a trend toward an increased mortality risk and empirical carbapenem therapy was associated with a trend toward decreased mortality risk.

Observer bias in hand hygiene compliance reporting.

Differences in reported hand hygiene compliance rates were assessed on the basis of the unit affiliation of observers. In 2 hospitals, unit-based observers more often reported higher compliance rates than did non-unit-based observers (79% vs 58.6%; difference, 20.4%; P<.001). Nonstandardized data collection methods contribute to the variability in hand hygiene compliance rates.