To ascertain which components of healthcare worker (HCW) influenza vaccination programs are associated with higher vaccination rates.

Survey.

University-affiliated hospitals.

Participating hospitals were surveyed with regard to their institutional HCW influenza vaccination program for the 2007-2008 influenza season. Topics assessed included vaccination adherence and availability, use of declination statements, education methods, accountability, and data reporting. Factors associated with higher vaccination rates were ascertained.

Fifty hospitals representing 368,696 HCWs participated in the project. The median vaccination rate was 55.0% (range, 25.6%-80.6%); however, the types of HCWs targeted by vaccination programs varied. Programs with the following components had significantly higher vaccination rates: weekend provision of vaccine (58.8% in those with this feature vs 43.9% in those without; P = .01), train-the-trainer programs (59.5% vs 46.5%; P = .005), report of vaccination rates to administrators (57.2% vs 48.1%; P = .04) or to the board of trustees (63.9% vs 53.4%; P = .01), a letter sent to employees emphasizing the importance of vaccination (59.3% vs 47%; P = .01), and any form of visible leadership support (57.9% vs 36.9%; P = .01). Vaccination rates were not significantly different between facilities that did and those that did not require a signed declination form for HCWs who refused vaccination (56.9% vs 55.1%; P = .68), although the precise content of such statements varied.

Vaccination programs that emphasized accountability to the highest levels of the organization, provided weekend access to vaccination, and used train-the-trainer programs had higher vaccination coverage. Of concern, the types of HCWs targeted by vaccination programs differed, and uniform definitions will be essential in the event of public reporting of vaccination rates.

States, including Illinois, have passed legislation mandating the use of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for reporting healthcare-associated infections, such as methicillin-resistant Staphylococcus aureus (MRSA).

To evaluate the sensitivity of ICD-9-CM code combinations for detection of MRSA infection and to understand implications for reporting.

We reviewed discharge and microbiology databases from July through August of 2005, 2006, and 2007 for ICD-9-CM codes or microbiology results suggesting MRSA infection at a tertiary care hospital near Chicago, Illinois. Medical records were reviewed to confirm MRSA infection. Time from admission to first positive MRSA culture result was evaluated to identify hospital-onset MRSA (HO-MRSA) infections. The sensitivity of MRSA code combinations for detecting confirmed MRSA infections was calculated using all codes present in the discharge record (up to 15); the effect of reviewing only 9 diagnosis codes, the number reported to the Centers for Medicare and Medicaid Services, was also evaluated. The sensitivity of the combination of diagnosis codes for detection of HO-MRSA infections was compared with that for community-onset MRSA (CO-MRSA) infections.

We identified 571 potential MRSA infections with the use of screening criteria; 403 (71%) were confirmed MRSA infections, of which 61 (15%) were classified as HO-MRSA. The sensitivity of MRSA code combinations was 59% for all confirmed MRSA infections when 15 diagnoses were reviewed compared with 31% if only 9 diagnoses were reviewed (P < .001). The sensitivity of code combinations was 33% for HO-MRSA infections compared with 62% for CO-MRSA infections (P < .001).

Limiting analysis to 9 diagnosis codes resulted in low sensitivity. Furthermore, code combinations were better at revealing CO-MRSA infections than HO-MRSA infections. These limitations could compromise the validity of ICD-9-CM codes for interfacility comparisons and for reporting of healthcare-associated MRSA infections.

USA300 is the most prevalent strain type of community-acquired methicillin-resistant Staphylococcus aureus (MRSA), but the proportion of patients colonized with USA300 strains and their risk for infection are largely unknown.

To determine the prevalence of USA300 strains among MRSA nasal colonizing isolates in our hospital, to identify risks for USA300 nasal colonization, and to determine risks of developing infection for nasally colonized patients.

Retrospective cohort study of patients found to be nasally colonized with MRSA through active surveillance at a tertiary care hospital from January 2005 through December 2007. MRSA isolates were identified as USA300 or non-USA300. Risks for colonization and infection were identified with logistic regression.

Among 1,306 MRSA nasal isolates, 307 (24%) were USA300 strains, and this proportion significantly increased over time (17.4% in 2005 and 26.7% in 2007; P = .003). African American race was an independent risk for USA300 nasal colonization (odds ratio [OR], 1.81 [95% confidence ratio {CI}, 1.38-2.38]). Older age (OR, 0.97 [95% CI, 0.96-0.98]) and female sex (OR, 0.74 [95% CI, 0.56-0.97]) decreased risk. Among nasally colonized patients, 238 (18.2%) developed infection. Increased length of stay (OR, 1.03 [95% CI, 1.01-1.06]) independently increased risk for infection among patients nasally colonized with USA300 MRSA, and female sex decreased risk (OR, 0.48 [95% CI, 0.24-0.95]). Increased length of stay (OR, 1.03 [95% CI, 1.02-1.04]) and treatment in an intensive care unit (OR, 1.64 [95% CI, 1.10-2.44]) independently increased risk for infection among patients nasally colonized with non-USA300 MRSA, and female sex decreased risk (OR, 0.67 [95% CI, 0.47-0.94]).

The proportion of MRSA nasally colonized patients with USA300 strains significantly increased during the study, and risks included African American race. Strain type had no significant effect on the proportion of patients who developed infection, and risk factors for infection were similar.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to almost all antimicrobial agents, and CRKP infections are associated with substantial morbidity and mortality.

To describe an outbreak of CRKP in Puerto Rico, determine risk factors for CRKP acquisition, and detail the successful measures taken to control the outbreak.

Two case-control studies.

A 328-bed tertiary care teaching hospital.

Twenty-six CRKP case patients identified during the outbreak period of February through September 2008, 26 randomly selected uninfected control patients, and 26 randomly selected control patients with carbapenem-susceptible K. pneumoniae (CSKP) hospitalized during the same period.

We performed active case finding, including retrospective review of the hospital's microbiology database and prospective perirectal surveillance culture sampling in high-risk units. Case patients were compared with each control group while controlling for time at risk. We sequenced the blaKPC gene with polymerase chain reaction for 7 outbreak isolates and subtyped these isolates with pulsed-field gel electrophoresis.

In matched, multivariable analysis, the presence of wounds (hazard ratio, 19.0 [95% confidence interval {CI}, 2.5-142.0]) was associated with CRKP compared with no K. pneumoniae. Transfer between units (adjusted odds ratio [OR], 7.5 [95% CI, 1.8-31.1]), surgery (adjusted OR, 4.0 [95% CI, 1.0-15.7]), and wounds (adjusted OR, 4.9 [95% CI, 1.1-21.8]) were independent risk factors for CRKP compared to CSKP. A novel K. pneumoniae carbapenemase variant (KPC-8) was present in 5 isolates. Implementation of active surveillance for CRKP colonization and cohorting of CRKP patients rapidly controlled the outbreak.

Enhanced surveillance for CRKP colonization and intensified infection control measures that include limiting the physical distribution of patients can reduce CRKP transmission during an outbreak.

Ertapenem exposure has been reported to select for cross-resistance to other carbapenems in Pseudomonas aeruginosa in vitro. Single-center investigations report conflicting results. We evaluated ertapenem use and antipseudomonal carbapenem susceptibility for 6 years spanning the time of ertapenem adoption at each of 25 US hospitals.

Retrospective primary and secondary data analysis.

Use density ratios for imipenem and meropenem (collectively, “other carbapenems”) and ertapenem were derived from data in a commercial database on the total number of grams used in the 3 years before and the 3 years after adoption of ertapenem at each hospital. A general linear model using repeated measures analysis of variance was used to explore associations between the 6-year change in antipseudomonal carbapenem susceptibility rates (determined from hospital antibiograms) and ertapenem use in each year, while controlling for other carbapenem use.

Ertapenem use increased once adopted. With regard to the postadoption period, the median use density ratio for year 4 was 4.1 (interquartile range [IQR], 1.7-5.2), for year 5 was 6.0 (IQR, 2.7-8.5), and for year 6 was 6.5 (IQR, 4.0-11.6). The median use density ratio for other carbapenem use for year 1 was 8.7 (IQR, 5.7-13.5), and by year 6 it had increased to 19.3 (IQR, 9.6-26.2). Change in mean antipseudomonal carbapenem susceptibility across time (85% in year 1 to 82% in year 6) was not significant (P = .22). Change in 6-year antipseudomonal carbapenem susceptibility was not associated with ertapenem use in any year while controlling for other carbapenem use (P > .20 for all years of ertapenem use).

Although significant change in P. aeruginosa susceptibility to antipseudomonal carbapenems was not detected during this multicenter study, which to our knowledge is the most extensive assessment to date of this important drug use-susceptibility relationship, continued evaluation of the relationship is prudent.

To compare the efficacy of universal gloving with emollient-impregnated gloves with standard contact precautions for the control of multidrug-resistant organisms (MDROs) and to measure the effect on healthcare workers' (HCWs') hand skin health.

Prospective before-after trial.

An 18-bed surgical intensive care unit.

During phase 1 (September 2007 through March 2008) standard contact precautions were used. During phase 2 (March 2008 through September 2008) universal gloving with emollient-impregnated gloves was used, and no contact precautions. Patients were screened for vancomycin-resistant Enterococcus (VRE) and methicillin-resistant Staphylococcus aureus (MRSA). HCW hand hygiene compliance and hand skin health and microbial contamination were assessed. The incidences of device-associated infection and Clostridium difficile infection (CDI) were determined.

The rate of compliance with contact precautions (phase 1) was 67%, and the rate of compliance with universal gloving (phase 2) was 78% (P = .01). Hand hygiene compliance was higher during phase 2 than during phase 1 (before patient care, 40% vs 35% of encounters; P = .001; after patient care, 63% vs 51% of encounters; P < .001). No difference was observed in MDRO acquisition. During phases 1 and 2, incidences of device-related infections, in number of infections per 1,000 device-days, were, respectively, 3.7 and 2.6 for bloodstream infection (P = .10), 8.9 and 7.8 for urinary tract infection (P = .10), and 1.0 and 1.1 for ventilator-associated pneumonia (P = .09). The CDI incidence in phase 1 and in phase 2 was, respectively, 2.0 and 1.4 cases per 1,000 patient-days (P = .53). During phase 1, 29% of HCW hand cultures were MRSA positive, compared with 13% during phase 2 (P = .17); during phase 1, 2% of hand cultures were VRE positive, compared with 0 during phase 2 (P = .16). Hand skin health improved during phase 2.

Compared with contact precautions, universal gloving with emollient-impregnated gloves was associated with improved hand hygiene compliance and skin health. No statistically significant change in the rates of device-associated infection, CDI, or patient MDRO acquisition was observed. Universal gloving may be an alternative to contact precautions.

Needlestick injuries are always associated with a risk of infection, because these types of punctures may expose healthcare workers to a patient's blood and/or body fluids.

To compare the efficacy of 4 different types of surgical gloves for preventing exposure to blood as a result of needlestick injury.

For simulation of needlestick injury, a circular sample of pork skin was tightened onto a bracket, and a single finger from a medical glove was stretched over the sample. First, a powder-free surgical glove with a gel coating was used to test blood contact. Second, a glove with a patented puncture indication system was used to test blood contact with a double-gloved hand. Third, 2 powder-free latex medical gloves of the same size and hand were combined for double gloving, again to test blood contact. Finally, we tested a glove with an integrated disinfectant on the inside. The punctures were carried out using diverse sharp surgical devices that were contaminated with 99Tc-marked blood. The amount of blood contact was determined from the transmitted radioactivity.

For the powder-free surgical glove with a gel coating, a mean volume of 0.048 μL of blood (standard error of the mean [SEM], 0.077 μL.) was transferred in punctures with an automated lancet at a depth of 2.4 mm through 1 layer of latex. For the glove with an integrated disinfectant on the inside, the mean volume of blood transferred was 0.030 μL (SEM, 0.0056 μL) with a single glove and was 0.024 μL (SEM, 0.003 μL) with 2 gloves. For the glove with the patented puncture indication system, a mean volume of 0.024 μL, (SEM, 0.003 μL) of blood was transferred.

Double gloving or the use of a glove with disinfectant can result in a decrease in the volume of blood transferred. Therefore, the use of either of these gloving systems could help to minimize the risk of bloodborne infections for medical staff.

To compare the surgical site infection (SSI) rate after primary total hip arthroplasty with the SSI rate after revision total hip arthroplasty.

Retrospective cohort study.

Mayo Clinic in Rochester, Minnesota, a referral orthopedic center.

All patients undergoing primary total hip arthroplasty or revision total hip arthroplasty during the period from January 1, 2002, through December 31, 2006.

We obtained data on total hip arthroplasties from a prospectively maintained institutional surgical database. We reviewed data on SSIs collected prospectively as part of routine infection control surveillance, using the criteria of the Centers for Disease Control and Prevention for the definition of an SSI. We used logistic regression analyses to evaluate differences between the SSI rate after primary total hip arthroplasty and the SSI rate after revision total hip arthroplasty.

A total of 5,696 total hip arthroplasties (with type 1 wound classification) were analyzed, of which 1,381 (24%) were revisions. A total of 61 SSIs occurred, resulting in an overall SSI rate of 1.1% for all total hip arthroplasties. When stratified by the National Nosocomial Infection Surveillance (NNIS) risk index, SSI rates were 0.5%, 1.2%, and 1.6% in risk categories 0, 1, and 2, respectively. After controlling for the NNIS risk index, the risk of SSI after revision total hip arthroplasty was twice as high as that after primary total hip arthroplasty (odds ratio, 2.2 [95% confidence interval, 1.3-3.7]). In the analysis restricted to the development of deep incisional or organ space infections, the risk of SSI after revision total hip arthroplasty was nearly 4 times that after primary total hip arthroplasty (odds ratio, 3.9 [95% confidence interval, 2.0-7.6]).

Including revision surgeries in the calculation of SSI rates can result in higher infection rates for institutions that perform a larger number of revisions. Taking NNIS risk indices into account does not eliminate this effect. Differences between primary and revision surgeries should be considered in national standards for the reporting of SSIs.

To characterize the current economic burden of ventilator-associated pneumonia (VAP) and to determine which services increase the cost of VAP in North American hospitals.

We performed a retrospective, matched cohort analysis of mechanically ventilated patients enrolled in the North American Silver-Coated Endotracheal Tube (NASCENT) study, a prospective, randomized study conducted from 2002 to 2006 in 54 medical centers, including 45 teaching institutions (83.3%).

Case patients with microbiologically confirmed VAP (n = 30) were identified from 542 study participants with claims data and were matched by use of a primary diagnostic code, and subsequently by the Acute Physiology and Chronic Health Evaluation II score, to control patients without VAP (n = 90). Costs were estimated by applying hospital-specific cost-to-charge ratios based on all-payer inpatient costs associated with VAP diagnosis-related groups.

Median total charges per patient were $198,200 for case patients and $96,540 for matched control patients (P <.001); corresponding median hospital costs were $76,730 for case patients and $41,250 for control patients (P = .001). After adjusting for diagnosis-related group payments, median losses to hospitals were $32,140 for case patients and $19,360 for control patients (P = .151). The median duration of intubation was longer for case patients than for control patients (10.1 days vs 4.7 days; P < .001), as were the median duration of intensive care unit stay (18.5 days vs 8.0 days; P < .001) and the median duration of hospitalization (26.5 days vs 14.0 days; P < .001). Examples of services likely to be directly related to VAP and having higher median costs for case patients were hospital care (P < .05) and respiratory therapy (P < .05).

VAP was associated with increased hospital costs, longer duration of hospital stay, and a higher number of hospital services being affected, which underscores the need for bundled measures to prevent VAP.

NASCENT study ClinicalTrials.gov Identifier: NCT00148642.

To investigate an outbreak of healthcare-associated Burkholderia cepacia complex (BCC) primary bloodstream infections (BCC-BSI).

Case-crossover study in a public hospital, a university hospital and a private hospital in Rio de Janeiro, Brazil, from March 2006 to May 2006.

Twenty-five patients with BCC-BSI.

After determining the date BCC-BSI symptoms started for each patient, 3 time intervals of data collection were defined, each one with a duration of 3 days: the case period, starting just before BCC-BSI symptoms onset; the control period, starting 6 days before BCC-BSI symptoms onset; and the washout period, comprising the 3 days between the case period and the control period. Exposures evaluated were intravascular solutions and invasive devices and procedures. Potential risk factors were identified by using the McNemar χ2 adjusted test. Cultures of samples of potentially contaminated solutions were performed. BCC strain typing was performed by pulsed-field gel electrophoresis using Spel.

The statistical analysis revealed that the use of bromopride and dipyrone was associated with BCC-BSI. A total of 21 clinical isolates from 17 (68%) of the 25 patients and an isolate obtained from the bromopride vial were available for strain typing. Six pulsotypes were detected. A predominant pulsotype (A) accounted for 11 isolates obtained from 11 patients (65%) in the 3 study hospitals.

Our investigation, using a case-crossover design, of an outbreak of BCC-BSI infections concluded it was polyclonal but likely caused by infusion of contaminated bromopride. The epidemiological finding was validated by microbiological analysis. After recall of contaminated bromopride vials by the manufacturer, the outbreak was controlled.

To identify risk factors for polymicrobial bloodstream infections (BSIs) in pediatric bone marrow transplant (BMT) outpatients attending a newly constructed clinic affiliated with a children's hospital.

All 30 outpatients treated at a new BMT clinic during September 10-21, 2007, were enrolled in a cohort study. The investigation included interviews, medical records review, observations, and bacterial culture and molecular typing of patient and environmental isolates. Data were analyzed using exact conditional logistic regression.

Thirteen patients experienced BSIs caused by 16 different, predominantly gram-negative organisms. Presence of a tunneled catheter (odds ratio [OR], 19.9 [95% confidence interval {CI}, 2.4-∞), catheter access (OR, 13.7 [95% CI, 1.8-∞]), and flushing of a catheter with predrawn saline (OR, 12.9 [95% CI, 1.0-766.0]) were independently associated with BSI. The odds of experiencing a BSI increased by a factor of 16.8 with each additional injection of predrawn saline (95% CI, 1.8-827.0). Although no environmental source of pathogens was identified, interviews revealed breaches in recommended infection prevention practice and medication handling. Saline flush solutions were predrawn, and multiple doses were obtained from single-dose preservative-free vials to avoid delays in patient care.

We speculate that infection prevention challenges in the new clinic, combined with successive needle punctures of vials, facilitated extrinsic contamination and transmission of healthcare-associated pathogens. We recommend that preservative-free single-use vials not be punctured more than once. Use of single-use prefilled saline syringes might prevent multiuse of single-use saline vials. Storage of saline outside a medication supply system might be advisable. Before opening new clinic facilities, hospitals should consider conducting a mock patient flow exercise to identify infection control challenges.