National Healthcare Safety Network (NHSN) report: data summary for 2006 through 2008, issued December 2009

Impact of a multidimensional infection control strategy on central line-associated bloodstream infection rates in pediatric intensive care units of five developing countries: findings of the International Nosocomial Infection Control Consortium (INICC)

PURPOSE

To analyze the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional infection control strategy including a practice bundle to reduce the rates of central line-associated bloodstream infection (CLAB) in patients hospitalized in pediatric intensive care units (PICUs) of hospitals, which are members of the INICC, from nine cities of five developing countries: Colombia, India, Mexico, Philippines, and Turkey.

METHODS

CLAB rates were determined by means of a prospective surveillance study conducted on 1,986 patients hospitalized in nine PICUs, over a period of 12,774 bed-days. The study was divided into two phases. During Phase 1 (baseline period), active surveillance was performed without the implementation of the multi-faceted approach. CLAB rates obtained in Phase 1 were compared with CLAB rates obtained in Phase 2 (intervention period), after implementation of the INICC multidimensional infection control program.

RESULTS

During Phase 1, 1,029 central line (CL) days were recorded, and during Phase 2, after implementing the CL care bundle and interventions, we recorded 3,861 CL days. The CLAB rate was 10.7 per 1,000 CL days in Phase 1, and in Phase 2, the CLAB rate decreased to 5.2 per 1,000 CL days (relative risk [RR] 0.48, 95% confidence interval [CI] 0.29-0.94, P = 0.02), showing a reduction of 52% in the CLAB rate.

CONCLUSIONS

This study shows that the implementation of a multidimensional infection control strategy was associated with a significant reduction in the CLAB rates in the PICUs of developing countries.

The metal ion-dependent adhesion site motif of the Enterococcus faecalis EbpA pilin mediates pilus function in catheter-associated urinary tract infection

Though the bacterial opportunist Enterococcus faecalis causes a myriad of hospital-acquired infections (HAIs), including catheter-associated urinary tract infections (CAUTIs), little is known about the virulence mechanisms that it employs. However, the endocarditis- and biofilm-associated pilus (Ebp), a member of the sortase-assembled pilus family, was shown to play a role in a mouse model of E. faecalis ascending UTI. The Ebp pilus comprises the major EbpC shaft subunit and the EbpA and EbpB minor subunits. We investigated the biogenesis and function of Ebp pili in an experimental model of CAUTI using a panel of chromosomal pilin deletion mutants. A nonpiliated pilus knockout mutant (EbpABC(-) strain) was severely attenuated compared to its isogenic parent OG1RF in experimental CAUTI. In contrast, a nonpiliated ebpC deletion mutant (EbpC(-) strain) behaved similarly to OG1RF in vivo because it expressed EbpA and EbpB. Deletion of the minor pilin gene ebpA or ebpB perturbed pilus biogenesis and led to defects in experimental CAUTI. We discovered that the function of Ebp pili in vivo depended on a predicted metal ion-dependent adhesion site (MIDAS) motif in EbpA's von Willebrand factor A domain, a common protein domain among the tip subunits of sortase-assembled pili. Thus, this study identified the Ebp pilus as a virulence factor in E. faecalis CAUTI and also defined the molecular basis of this function, critical knowledge for the rational development of targeted therapeutics.

IMPORTANCE

Catheter-associated urinary tract infections (CAUTIs), one of the most common hospital-acquired infections (HAIs), present considerable treatment challenges for physicians. Inherently resistant to several classes of antibiotics and with a propensity to acquire vancomycin resistance, enterococci are particularly worrisome etiologic agents of CAUTI. A detailed understanding of the molecular basis of Enterococcus faecalis pathogenesis in CAUTI is necessary for the development of preventative and therapeutic strategies. Our results elucidated the importance of the E. faecalis Ebp pilus and its subunits for enterococcal virulence in a mouse model of CAUTI. We further showed that the metal ion-dependent adhesion site (MIDAS) motif in EbpA is necessary for Ebp function in vivo. As this motif occurs in other sortase-assembled pili, our results have implications for the molecular basis of virulence not only in E. faecalis CAUTI but also in additional infections caused by enterococci and other Gram-positive pathogens.

Preventing hospital-acquired infections: a national survey of practices reported by U.S. hospitals in 2005 and 2009

BACKGROUND

Hospital-acquired infection (HAI) is common, costly, and potentially lethal. Whether initiatives to reduce HAI--such as the Centers for Medicare and Medicaid Services (CMS) no payment rule--have increased the use of preventive practices is not known.

OBJECTIVE

To examine the use of infection prevention practices by U.S. hospitals and trends in use between 2005 and 2009.

DESIGN, SETTING, AND PARTICIPANTS

Surveys of infection preventionists at non-federal general medical/surgical hospitals and Department of Veterans Affairs (VA) hospitals, which are not subject to the CMS no payment rule, in 2005 and 2009.

MAIN MEASURES

Percent of hospitals using practices to prevent central line-associated bloodstream infection (CLABSI), ventilator-associated pneumonia (VAP), and catheter-associated urinary tract infection (CAUTI).

KEY RESULTS

Survey response was approximately 70%. More than 1/2 of non-federal hospitals reported a moderate or large increase in CLABSI, VAP and CAUTI prevention as a facility priority due to the non-payment rule; over 60% of VA hospitals reported no change in priority. However, both non-federal and VA hospitals reported significant increases in use of most practices to prevent CLABSI, VAP and CAUTI from 2005 to 2009, with 90% or more using certain practices to prevent CLABSI and VAP in 2009. In contrast, only one CAUTI prevention practice was used by at least 50% of hospitals.

CONCLUSIONS

Since 2005, use of key practices to prevent CLABSI, VAP and CAUTI has increased in non-federal and VA hospitals, suggesting that despite its perceived importance, the non-payment rule may not be the primary driver. Moreover, while 65% of non-federal hospitals reported a moderate or large increase in preventing CAUTI as a facility priority, prevention practice use remains low.

Socioeconomic impact on device-associated infections in pediatric intensive care units of 16 limited-resource countries: international Nosocomial Infection Control Consortium findings

OBJECTIVES

We report the results of the International Nosocomial Infection Control Consortium prospective surveillance study from January 2004 to December 2009 in 33 pediatric intensive care units of 16 countries and the impact of being in a private vs. public hospital and the income country level on device-associated health care-associated infection rates. Additionally, we aim to compare these findings with the results of the Centers for Disease Control and Prevention National Healthcare Safety Network annual report to show the differences between developed and developing countries regarding device-associated health care-associated infection rates.

PATIENTS

A prospective cohort, active device-associated health care-associated infection surveillance study was conducted on 23,700 patients in International Nosocomial Infection Control Consortium pediatric intensive care units.

METHODS

The protocol and methodology implemented were developed by International Nosocomial Infection Control Consortium. Data collection was performed in the participating intensive care units. Data uploading and analyses were conducted at International Nosocomial Infection Control Consortium headquarters on proprietary software. Device-associated health care-associated infection rates were recorded by applying Centers for Disease Control and Prevention National Healthcare Safety Network device-associated infection definitions, and the impact of being in a private vs. public hospital and the income country level on device-associated infection risk was evaluated.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Central line-associated bloodstream infection rates were similar in private, public, or academic hospitals (7.3 vs. 8.4 central line-associated bloodstream infection per 1,000 catheter-days [p < .35 vs. 8.2; p < .42]). Central line-associated bloodstream infection rates in lower middle-income countries were higher than low-income countries or upper middle-income countries (12.2 vs. 5.5 central line-associated bloodstream infections per 1,000 catheter-days [p < .02 vs. 7.0; p < .001]). Catheter-associated urinary tract infection rates were similar in academic, public and private hospitals: (4.2 vs. 5.2 catheter-associated urinary tract infection per 1,000 catheter-days [p = .41 vs. 3.0; p = .195]). Catheter-associated urinary tract infection rates were higher in lower middle-income countries than low-income countries or upper middle-income countries (5.9 vs. 0.6 catheter-associated urinary tract infection per 1,000 catheter-days [p < .004 vs. 3.7; p < .01]). Ventilator-associated pneumonia rates in academic hospitals were higher than private or public hospitals: (8.3 vs. 3.5 ventilator-associated pneumonias per 1,000 ventilator-days [p < .001 vs. 4.7; p < .001]). Lower middle-income countries had higher ventilator-associated pneumonia rates than low-income countries or upper middle-income countries: (9.0 vs. 0.5 per 1,000 ventilator-days [p < .001 vs. 5.4; p < .001]). Hand hygiene compliance rates were higher in public than academic or private hospitals (65.2% vs. 54.8% [p < .001 vs. 13.3%; p < .01]).

CONCLUSIONS

Country socioeconomic level influence device-associated infection rates in developing countries and need to be considered when comparing device-associated infections from one country to another.

Surgical site infection after breast surgery: impact of 2010 CDC reporting guidelines

BACKGROUND

Reported surgical site infection (SSI) rates after breast operations ranges 0.8-26 % in the literature. The aims of the present study were to characterize SSI after breast/axillary operations and determine the impact on the SSI rate of the 2010 Centers for Disease Control and Prevention (CDC) reporting guidelines that now specifically exclude cellulitis.

METHODS

Retrospective chart review identified 368 patients with 449 operated sides between July 2004 and June 2006. SSI was defined by CDC criteria: purulent drainage (category 1), positive aseptically collected culture (category 2), signs of inflammation with opening of incision and absence of negative culture (category 3), and physician diagnosis of infection (category 4). The impact of excluding cellulitis was assessed.

RESULTS

Prior CDC reporting guidelines revealed that among 368 patients, 32 (8.7 %) experienced SSI in 33 (7.3 %) of 449 operated sides. Of these, 11 (33 %) met CDC criteria 1-3, while 22 (67 %) met CDC criterion 4. Excluding cellulitis cases per 2010 CDC SSI reporting guidelines eliminates 21 of the 22 infections previously meeting CDC criterion 4. Under the new reporting guidelines, the SSI rate is 12 (2.7 %) of 449 operated sides. SSI rates varied by procedure, but these differences were not statistically significant.

CONCLUSIONS

Cellulitis after breast and axillary surgery is much more common than other criteria for SSI, and SSI rates are reduced almost threefold if cellulitis cases are excluded. Recently revised CDC reporting guidelines may result in underestimates of the clinical burden of SSI after breast/axillary surgery.

Preventing ventilator-associated pneumonia: does the evidence support the practice?

Ventilator-associated pneumonia (VAP) is among the most common infections in patients requiring endotracheal tubes with mechanical ventilation. Ventilator-associated pneumonia is associated with increased hospital costs, a greater number of days in the intensive care unit, longer duration of mechanical ventilation, and higher mortality. Despite widely accepted recommendations for interventions designed to reduce rates of VAP, few studies have assessed the ability of these interventions to improve patient outcomes. As the understanding of VAP advances and new technologies to reduce VAP become available, studies should directly assess patient outcomes before the health care community implements specific prevention approaches in clinical practice.

Preventive strategies for central line-associated bloodstream infections in pediatric hematopoietic stem cell transplant recipients

BACKGROUND

Few studies have described preventive strategies for central line-associated bloodstream infections (CLABSIs) in pediatric hematopoietic stem cell transplantation (HSCT) recipients.

METHODS

We performed a pilot intervention study in our pediatric HSCT population in 2006-2008 and compared CLABSI rates before and after implementation of preventive strategies (ie, training staff and caregivers in procedures for dressing changes and drawing blood) in the inpatient, outpatient, and non-health care (ie, home) settings. We also studied the pathogens associated with hospital-onset versus community-onset CLABSIs.

RESULTS

During the study period, 90 children (median age, 10 years) underwent HSCT. Fifty-nine children (66%) developed a CLABSI; 18 in the hospital, 27 in the community, and 14 in both settings. After implementation of central line (CL) maintenance care strategies, the overall CLABSI rate declined from 10.03 to 3.00 CLABSIs per 1,000 CL-days (rate ratio, 0.3; 95% confidence interval, 0.2-0.5, P < .0001) and rates declined for both hospital- and community-onset CLABSIs. Gram negative pathogens caused more community-onset (45/65, 69%) than hospital-onset (22/46, 48%) CLABSIs (odds ratio, 2.5; 95% confidence interval, 1.1-5.4; P = .02).

CONCLUSIONS

Standardization of care practices for CL maintenance was associated with a reduction of CLABSIs in our pediatric HSCT population. A multicenter study is needed to confirm these observations.

A novel method of surgical site infection surveillance after cardiac surgery by active participation of stake holders

We describe a comprehensive surveillance system involving infection control practitioners, surgeons, administrative staff, and patients aimed at improving the postdischarge surveillance of surgical site infections. The system was able to detect 22 infections out of 538 procedures, 95% of which were detected during the postdischarge period.

Implementation of the World Health Organization surgical safety checklist at a university hospital in Thailand

BACKGROUND

Compliance with the World Health Organization (WHO) surgical safety checklist may reduce preventable adverse events. However, compliance may be difficult to implement in Thailand. This study was conducted to examine compliance with the WHO checklist at a Thai university hospital.

METHODS

A descriptive study was conducted among 4,340 patients undergoing surgery in nine departments from March to August 2009. The compliance rates were computed.

RESULTS

The highest compliance rate (91.4%) during the sign-in period was with patients' confirmation of their identity, operative site, procedure, and consent. However, only 19.4% of the surgical sites were marked. In the time-out period, surgical teams had introduced themselves by name and role in 79% of the operations; and in 95.7% of the cases, the patient's name, the incision site, and the procedure had been confirmed. Antibiotic prophylaxis had been given within 60 min before the incision in 71% of the cases. For 83% of the operations, the surgeons reviewed crucial events whereas only 78.4% were reviewed by the anesthetists. Sterility had been confirmed by the operating room nurses for every patient, but the essential imaging was displayed at a rate of only 64.4%. In the sign-out period, nurses correctly confirmed the name of the procedure orally in 99.5% of the cases. Instrument, sponge, and needle counts were completed and the specimen was labeled in most cases, 96.8% and 97.6%, respectively. Equipment-related problems were identified in 4.4% of the cases, and 100% of them were addressed. The surgeon, anesthetist, and nurse reviewed the key concerns for recovery and management of the patient at the rate of 85.1%.

CONCLUSIONS

The WHO checklist can be implemented in a developing country. However, compliance with some items was extremely low, reflecting different work patterns and cultural norms. Additional education and enforcement of checklist use is needed to improve compliance.

Urethral catheter-related urinary infection in critical patients admitted to the ICU. Descriptive data of the ENVIN-UCI study

OBJECTIVE

To describe trends in national catheter-related urinary tract infection (CRUTI) rates, as well as etiologies and multiresistance markers.

DESIGN

An observational, prospective, multicenter voluntary participation study was conducted from 1 April to 30 June in the period between 2005 and 2010.

SETTING

Intensive Care Units (ICUs) that participated in the ENVIN-ICU registry during the study period.

PATIENTS

We included all patients admitted to the participating ICUs and patients with urinary catheter placement for more than 24 hours (78,863 patients).

INTERVENTION

Patient monitoring was continued until discharge from the ICU or up to 60 days.

VARIABLES OF INTEREST

CRUTIs were defined according to the CDC system, and frequency is expressed as incidence density (ID) in relation to the number of urinary catheter-patients days.

RESULTS

A total of 2329 patients (2.95%) developed one or more CRUTI. The ID decreased from 6.69 to 4.18 episodes per 1000 days of urinary catheter between 2005 and 2010 (p<0.001). In relation to the underlying etiology, gramnegative bacilli predominated (55.6 to 61.6%), followed by fungi (18.7 to 25.2%) and grampositive cocci (17.1 to 25.9%). In 2010, ciprofloxacin-resistant E. coli strains (37.1%) increased, as well as imipenem-resistant (36.4%) and ciprofloxacin-resistant (37.1%) strains of P. aeruginosa.

CONCLUSIONS

A decrease was observed in CRUTI rates, maintaining the same etiological distribution and showing increased resistances in gramnegative pathogens, especially E. coli and P. aeruginosa.

Prospective evaluation of sedation-related adverse events in pediatric patients ventilated for acute respiratory failure

OBJECTIVES

Sedation-related adverse events in critically ill pediatric patients lack reproducible operational definitions and reference standards. Understanding these adverse events is essential to improving the quality of patient care and for developing prevention strategies in critically ill children. The purpose of this study was to test operational definitions and estimate the rate and site-to-site heterogeneity of sedation-related adverse events.

DESIGN

Prospective cohort study.

SETTING

Twenty-two pediatric intensive care units in the United States enrolling baseline patients into a prerandomization phase of a multicenter trial on sedation management.

PATIENTS

Pediatric patients intubated and mechanically ventilated for acute respiratory failure.

DATA EXTRACTION

Analysis of adverse event data using consistent operational definitions from a Web-based data management system.

MEASUREMENTS AND MAIN RESULTS

There were 594 sedation-related adverse events reported in 308 subjects, for a rate of 1.9 adverse events per subject and 16.6 adverse events per 100 pediatric intensive care unit days. Fifty-four percent of subjects had at least one adverse event. Seven (1%) adverse events were classified as severe, 347 (58%) as moderate, and 240 (40%) as mild. Agitation (30% of subjects, 41% of events) and pain (27% of subjects, 29% of events) were the most frequently reported events. Eight percent of subjects (n = 24) experienced 54 episodes of clinically significant iatrogenic withdrawal. Unplanned endotracheal tube extubation occurred at a rate of 0.82 per 100 ventilator days, and 32 subjects experienced postextubation stridor. Adverse events with moderate intraclass correlation coefficients included: Inadequate sedation management (intraclass correlation coefficient = 0.130), clinically significant iatrogenic withdrawal (intraclass correlation coefficient = 0.088), inadequate pain management (intraclass correlation coefficient = 0.080), and postextubation stridor (intraclass correlation coefficient = 0.078).

CONCLUSIONS

Operational definitions for sedation-related adverse events were consistently applied across multiple pediatric intensive care units. Adverse event rates were different from what has been previously reported in single-center studies. Many adverse events have moderate intraclass correlation coefficients, signaling site-to-site heterogeneity.

Surveillance length and validity of benchmarks for central line-associated bloodstream infection incidence rates in intensive care units

Introduction

Several national and regional central line-associated bloodstream infections (CLABSI) surveillance programs do not require continuous hospital participation. We evaluated the effect of different hospital participation requirements on the validity of annual CLABSI incidence rate benchmarks for intensive care units (ICUs).

Methods

We estimated the annual pooled CLABSI incidence rates for both a real regional (<100 ICUs) and a simulated national (600 ICUs) surveillance program, which were used as a reference for the simulations. We simulated scenarios where the annual surveillance participation was randomly or non-randomly reduced. Each scenario's annual pooled CLABSI incidence rate was estimated and compared to the reference rates in terms of validity, bias, and proportion of simulation iterations that presented valid estimates (ideal if≥90%).

Results

All random scenarios generated valid CLABSI incidence rates estimates (bias −0.37 to 0.07 CLABSI/1000 CVC-days), while non-random scenarios presented a wide range of valid estimates (0 to 100%) and higher bias (−2.18 to 1.27 CLABSI/1000 CVC-days). In random scenarios, the higher the number of participating ICUs, the shorter the participation required to generate ≥90% valid replicates. While participation requirements in a countrywide program ranged from 3 to 13 surveillance blocks (1 block = 28 days), requirements for a regional program ranged from 9 to 13 blocks.

Conclusions

Based on the results of our model of national CLABSI reporting, the shortening of participation requirements may be suitable for nationwide ICU CLABSI surveillance programs if participation months are randomly chosen. However, our regional models showed that regional programs should opt for continuous participation to avoid biased benchmarks.

Guide to the elimination of orthopedic surgery surgical site infections: an executive summary of the Association for Professionals in Infection Control and Epidemiology elimination guide

This article is an executive summary of the APIC Guide to the Elimination of Orthopedic Surgical Site Infections. Infection preventionists, care providers, and perioperative personnel are encouraged to obtain the original, full length APIC Elimination Guide for more thorough coverage on strategies to prevent surgical site infections in orthopedic surgery.

Medical device SALs and surgical site infections: a mathematical model

It is commonly accepted that terminally sterilized healthcare products are rarely the source of a hospital-acquired infection (HAI). The vast majority of HAIs arise from human-borne contamination from the workforce, the clinical environment, less-than-aseptic handling techniques, and the patients themselves. Nonetheless, the requirement for a maximal sterility assurance level (SAL) of a terminally sterilized product has remained at 10(-6), which is the probability of one in one million that a single viable microorganism will be on a product after sterilization. This paper presents a probabilistic model that predicts choosing an SAL greater than 10(-6) (e.g. 10(-5) or 10(-4), and in some examples even 10(-3) or 10(-2)) does not have a statistically significant impact on the incidence of surgical site infections (SSIs). The use of a greater SAL might allow new, potentially life-saving products that cannot withstand sterilization to achieve a 10(-6) SAL to be terminally sterilized instead of being aseptically manufactured.

Guidelines to prevent catheter-associated urinary tract infection: 1980 to 2010

OBJECTIVES

We set out to review and compare guidelines to prevent catheter-associated urinary tract infection (CAUTI), examine the association between recent federal initiatives and CAUTI guidelines, and recommend practices for preventing CAUTI that are associated with strong evidence and are consistent across guidelines.

BACKGROUND

Catheter-associated urinary tract infections are the most common healthcare-associated infection, and a cause of significant morbidity and mortality in critically ill patients.

METHODS

A search of the English-language literature for guidelines in the prevention of adult CAUTI, published between 1980 and 2010, was conducted in Medline and the National Guideline Clearinghouse.

RESULTS

Many recommendations were consistent across 8 guidelines, including limited use of urinary catheters, the insertion of catheters aseptically, and the maintenance of a closed drainage system. The weight of evidence for some endorsed practices was limited, and different grading systems made comparisons across recommendations difficult. Federal initiatives are closely aligned with the 4 most recent guidelines.

CONCLUSION

Additional research into the prevention of CAUTI is needed, as is a harmonization of guideline grading systems for recommendations.

Introducing a population-based outcome measure to evaluate the effect of interventions to reduce catheter-associated urinary tract infection

BACKGROUND

The catheter-associated urinary tract infection (CAUTI) measure recommended by the National Healthcare Safety Network (NHSN) accounts for the risk of infection in patients with an indwelling urinary catheter, but might not adequately reflect all efforts aimed to enhance patient safety by reducing urinary catheter use.

METHODS

We used computer-based Monte Carlo simulation to compare the NHSN-recommended CAUTI rate (CAUTIs per 1,000 catheter-days) with the proposed "population CAUTI rate" (CAUTIs per 10,000 patient-days). We simulated 100 interventions with a wide range of effects on catheter utilization and CAUTI risk in patients with catheters, and then compared the 2 measures before and after intervention across the simulated interventions.

RESULTS

Out of our 100 simulated interventions, 93 yielded reductions in CAUTI; however, in 25 (27%) of these 93 simulations, the NHSN CAUTI rate increased after the intervention. In addition, among the 68 simulations in which both the NHSN and the population CAUTI rates decreased, the percent decreases in the population CAUTI rate were consistently greater than those in the NHSN rate.

CONCLUSION

The population CAUTI rate-CAUTIs per 10,000 patient-days-should be calculated along with the NHSN rate, particularly in settings where interventions lead to substantial reductions in catheter placement. We suspect that this population CAUTI rate may eventually emerge as a primary outcome for hospital-based quality improvement interventions for reducing urinary catheter utilization, especially those focusing on avoiding urinary catheter placement.

One evidence based protocol doesn't fit all: brushing away ventilator associated pneumonia in trauma patients

OBJECTIVES

Evaluate change in ventilator associated pneumonia (VAP) and nurse's attitudes, beliefs post implementation of an evidence based practice (EBP) oral hygiene protocol. METHODOLOGY/DESIGN/SETTING: Descriptive pre and post test design in two critical care units in a Level One Trauma Community Hospital. Oral hygiene protocol data was reanalysed to examine effects in medical surgical and trauma subgroups.

OUTCOME MEASURES

Oral care practices, attitudes and beliefs among nurses, and VAP rates according to Centers for Disease Control and Prevention guidelines.

RESULTS

Trauma rates increased from 6.4% to 10.0% (p=0.346), and medical/surgical rates decreased from 3.3% to 1.0% (p=0.042). Results revealed changes in nurses' beliefs regarding pre-admission colonisation (p=0.027) and having adequate training. Nurses' perception of facility support improved, by having suitable equipment and readily available supplies. Foam swabs with moisture agents at 4hours or less was 88.6% and toothbrush use at 12hours or less was 71%, with significant changes in frequency of oral care post intervention.

CONCLUSIONS

Trauma patients present with unique characteristics which compromise oral care. Understanding risk and prognostic factors, mechanisms of transmission and systemic inflammatory response are important when implementing EBP protocols. Nurses' attitudes, beliefs are important, and staff adherence considered when initiating EBP changes.

Prospective nationwide surveillance of surgical site infections after gastric surgery and risk factor analysis in the Korean Nosocomial Infections Surveillance System (KONIS)

OBJECTIVE

To evaluate the risk factors for surgical site infection (SSI) after gastric surgery in patients in Korea.

DESIGN

A nationwide prospective multicenter study.

SETTING

Twenty university-affiliated hospitals in Korea.

METHODS

The Korean Nosocomial Infections Surveillance System (KONIS), a Web-based system, was developed. Patients in 20 Korean hospitals from 2007 to 2009 were prospectively monitored for SSI for up to 30 days after gastric surgery. Demographic data, hospital characteristics, and potential perioperative risk factors were collected and analyzed, using multivariate logistic regression models.

RESULTS

Of the 4,238 case patients monitored, 64.9% (2,752) were male, and mean age (± SD) was 58.8 (± 12.3) years. The SSI rates were 2.92, 6.45, and 10.87 per 100 operations for the National Nosocomial Infections Surveillance system risk index categories of 0, 1, and 2 or 3, respectively. The majority (69.4%) of the SSIs observed were organ or space SSIs. The most frequently isolated microorganisms were Staphylococcus aureus and Klebsiella pneumoniae. Male sex (odds ratio [OR], 1.67 [95% confidence interval (CI), 1.09-2.58]), increased operation time (1.20 [1.07-1.34] per 1-hour increase), reoperation (7.27 [3.68-14.38]), combined multiple procedures (1.79 [1.13-2.83]), prophylactic administration of the first antibiotic dose after skin incision (3.00 [1.09-8.23]), and prolonged duration (≥7 days) of surgical antibiotic prophylaxis (SAP; 2.70 [1.26-5.64]) were independently associated with increased risk of SSI.

CONCLUSIONS

Male sex, inappropriate SAP, and operation-related variables are independent risk factors for SSI after gastric surgery.

Agreement among health care professionals in diagnosing case Vignette-based surgical site infections

OBJECTIVE

To assess agreement in diagnosing surgical site infection (SSI) among healthcare professionals involved in SSI surveillance.

METHODS

Case-vignette study done in 2009 in 140 healthcare professionals from seven specialties (20 in each specialty, Anesthesiologists, Surgeons, Public health specialists, Infection control physicians, Infection control nurses, Infectious diseases specialists, Microbiologists) in 29 University and 36 non-University hospitals in France. We developed 40 case-vignettes based on cardiac and gastrointestinal surgery patients with suspected SSI. Each participant scored six randomly assigned case-vignettes before and after reading the SSI definition on an online secure relational database. The intraclass correlation coefficient (ICC) was used to assess agreement regarding SSI diagnosis on a seven-point Likert scale and the kappa coefficient to assess agreement for superficial or deep SSI on a three-point scale.

RESULTS

Based on a consensus, SSI was present in 21 of 40 vignettes (52.5%). Intraspecialty agreement for SSI diagnosis ranged across specialties from 0.15 (95% confidence interval, 0.00-0.59) (anesthesiologists and infection control nurses) to 0.73 (0.32-0.90) (infectious diseases specialists). Reading the SSI definition improved agreement in the specialties with poor initial agreement. Intraspecialty agreement for superficial or deep SSI ranged from 0.10 (-0.19-0.38) to 0.54 (0.25-0.83) (surgeons) and increased after reading the SSI definition only among the infection control nurses from 0.10 (-0.19-0.38) to 0.41 (-0.09-0.72). Interspecialty agreement for SSI diagnosis was 0.36 (0.22-0.54) and increased to 0.47 (0.31-0.64) after reading the SSI definition.

CONCLUSION

Among healthcare professionals evaluating case-vignettes for possible surgical site infection, there was large disagreement in diagnosis that varied both between and within specialties.

Differences in management and mortality with a bronchoalveolar lavage-based diagnostic protocol for ventilator-associated pneumonia

BACKGROUND

Directed antibiotic therapy based on accurate bacteriology is critical to ventilator-associated pneumonia (VAP) treatment. Bronchoalveolar lavage (BAL) has been reported to be more accurate than endotracheal sputum aspirate (ESA) in VAP diagnosis. Our objective was to determine the frequency with which BAL results differ from ESA cultures and the outcomes of VAP with a BAL-based VAP protocol.

METHODS

Prospectively collected microbiologic data on all trauma patients with VAP from 2007 through 2009 were reviewed. Per protocol, a positive ESA prompts a BAL and initiation of broad empiric antibiotics with de-escalation based on BAL results. Patients diagnosed with VAP by the protocol were compared with those diagnosed outside of the protocol using univariate and multivariate linear regression analysis. Concordance of ESA and BAL results was evaluated, and cause of death was determined.

RESULTS

Of 137 patients with VAP, 96 were diagnosed by the protocol (protocol group) and had 102 pairs of cultures. Twenty-six patients (27%) with 28 pairs of cultures (27.4%) had discordant results. Of discordant pairs, 17 (61%) showed bacteria of a different Gram's stain. Methicillin-sensitive Staphylococcus aureus was the most common causative organism. Mortality was lower in the protocol group (6.3%) than the nonprotocol group (22%, p = 0.014) and mechanically ventilated patients without VAP (24%, p = 0.35) but with comparable Injury Severity Score (ISS). VAP-attributable mortality in the protocol group was 1%.

CONCLUSIONS

Use of a BAL-based diagnostic protocol affects management of trauma patients with VAP by improving identification of causative microorganisms and is associated with low overall mortality and VAP-attributable mortality.

Utilizing a line maintenance team to reduce central-line-associated bloodstream infections in a neonatal intensive care unit

OBJECTIVE

To determine the association of a central-line maintenance team on the incidence of central-line-associated bloodstream infections (CLABSIs) in the neonatal intensive care unit (NICU).

STUDY DESIGN

Central line maintenance in the NICU was limited to a line team starting in March 2008. CLABSI rates were determined before (December 2006 to February 2008) and after implementation of the line team ( March 2008 to August 2010) utilizing consistent National Healthcare Safety Network definitions. Rates were calculated by birth weight categories and overall. Data analysis was performed by two-proportion t test using Minitab.

RESULT

Overall CLABSI decreased by 65% after implementation of the line team. Pre intervention, mean overall CLABSI rate was 11.6 /1000, as compared with 4.0/1000 after intervention (P<0.001). Birth-weight-specific CLABSI rates also decreased significantly. Decreased infection rates were sustained over time.

CONCLUSION

A line team provided for standardized, consistent central-line maintenance care leading to a significant, sustained decrease in CLABSI in a NICU.

Epidemiology of central line-associated bloodstream infections in Quebec intensive care units: a 6-year review

BACKGROUND

The burden of central line-associated bloodstream infections (CLABSI) in Canadian intensive care units (ICUs) is not well established. The present study aimed to describe CLABSI epidemiology in Quebec ICUs during 2003-2009.

METHODS

The study population was a retrospective dynamic cohort of 58 ICUs that participated in the Surveillance Provinciale des Infections Nosocomiales program during 2003-2009. We calculated annual CLABSI incidence rates (IRs), central venous catheter (CVC) utilization ratios, and case-fatality proportions, and described the pathogens involved. We analyzed data using descriptive statistics and standardized incidence ratios.

RESULTS

A total of 891 CLABSIs were identified during 446,137 CVC-days. In 2003-2009, CLABSI IRs were 1.67 CLABSI/1,000 CVC-days in adult ICUs, 2.20 CLABSIs/1,000 CVC-days in pediatric ICUs, and 4.40 CLABSIs/1,000 CVC-days in neonatal ICUs. Since 2007, CLABSI IRs in adult, pediatric and neonatal ICUs have decreased by 11%, 50%, and 18%, respectively. Pediatric ICUs had the highest CVC utilization ratio (median, 0.61; interquartile range, 0.57-0.66). Coagulase-negative staphylococci caused 53% of the CLABSIs. The proportion of methicillin-resistant Staphylococcus aureus declined from 70% to <40% after 2006.

CONCLUSIONS

CLABSIs result in a considerable burden of illness in Quebec ICUs. However, CLABSI IRs have decreased since 2007, and the proportion of methicillin-resistant S aureus has remained <40% since 2006. Continuous surveillance is essential to determine whether these changes are sustainable.

Epidemiology and diagnosis of health care-associated infections in the NICU

Health care-associated infections in the NICU are a major clinical problem resulting in increased morbidity and mortality, prolonged length of hospital stays, and increased medical costs. Neonates are at high risk for health care-associated infections because of impaired host defense mechanisms, limited amounts of protective endogenous flora on skin and mucosal surfaces at time of birth, reduced barrier function of neonatal skin, the use of invasive procedures and devices, and frequent exposure to broad-spectrum antibiotics. This statement will review the epidemiology and diagnosis of health care-associated infections in newborn infants.

Medical device-associated infections in the long-term care setting

Indwelling medical devices are increasingly used in long-term care facilities (LTCFs). These devices place residents at a heightened risk for infection and colonization and infection with multidrug-resistant organisms. Understanding the risk and pathogenesis of infection associated with commonly used medical devices can help facilitate appropriate therapy. Programs to minimize unnecessary use of indwelling medical devices in residents and maximize staff adherence to infection control and maintenance procedures are essential features of a LTCF infection prevention program. LTCFs that provide care for large numbers of residents with indwelling medical devices should routinely perform surveillance for device-related infections and develop systems for assessing the safety and efficacy of newly introduced device-related technology.

Management and prevention of prosthetic joint infection

Prosthetic joint infection (PJI) is a serious complication of total joint arthroplasty (TJA) that can negatively affect functional status and quality of life. This article examines the epidemiology of PJI and reviews current diagnostic, treatment, and management strategies. Diagnosis can be challenging because presenting symptoms are often nonspecific and there is no simple gold standard diagnostic test. Successful treatment of PJI requires a combination of medical and surgical strategies. Given the devastating nature of PJI and the increasing numbers of TJAs performed, prevention efforts remain critical.

Improved risk adjustment in public reporting: coronary artery bypass graft surgical site infections

OBJECTIVE

The objective was to develop a new National Healthcare Safety Network (NHSN) risk model for sternal, deep incisional, and organ/space (complex) surgical site infections (SSIs) following coronary artery bypass graft (CABG) procedures, detected on admission and readmission, consistent with public reporting requirements.

PATIENTS AND SETTING

A total of 133,503 CABG procedures with 4,008 associated complex SSIs reported by 293 NHSN hospitals in the United States.

METHODS

CABG procedures performed from January 1, 2006, through December 31, 2008, were analyzed. Potential SSI risk factors were identified by univariate analysis. Multivariate analysis with forward stepwise logistic regression modeling was used to develop the new model. The c-index was used to compare the predictive power of the new and NHSN risk index models.

RESULTS

Multivariate analysis independent risk factors included ASA score, procedure duration, female gender, age, and medical school affiliation. The new risk model has significantly improved predictive performance over the NHSN risk index (c-index, 0.62 and 0.56, respectively).

CONCLUSIONS

Traditionally, the NHSN surveillance system has used a risk index to provide procedure-specific risk-stratified SSI rates to hospitals. A new CABG sternal, complex SSI risk model developed by multivariate analysis has improved predictive performance over the traditional NHSN risk index and is being considered for endorsement as a measure for public reporting.

Economic aspects of preventing health care-associated infections in the intensive care unit

Infection prevention is critical to providing a high standard of care in the intensive care unit (ICU). Recent focus on eliminating health care–associated infections (HAIs) has met with variable results. Although evidence-based as far as their components, policy-driven bundled HAI prevention interventions have been evaluated in a limited and potentially biased fashion for their effectiveness, and analyses of their cost-effectiveness are lacking. We use ventilator-associated pneumonia as the case study to illustrate the pitfalls and challenges of arriving at the optimal HAI preventive strategies in the ICU.

Management of antimicrobial use in the intensive care unit

Critically ill patients admitted to the intensive care unit (ICU) are frequently treated with antimicrobials. The appropriate and judicious use of antimicrobial treatment in the ICU setting is a constant clinical challenge for healthcare staff due to the appearance and spread of new multiresistant pathogens and the need to update knowledge of factors involved in the selection of multiresistance and in the patient's clinical response. In order to optimize the efficacy of empirical antibacterial treatments and to reduce the selection of multiresistant pathogens, different strategies have been advocated, including de-escalation therapy and pre-emptive therapy as well as measurement of pharmacokinetic and pharmacodynamic (pK/pD) parameters for proper dosing adjustment. Although the theoretical arguments of all these strategies are very attractive, evidence of their effectiveness is scarce. The identification of the concentration-dependent and time-dependent activity pattern of antimicrobials allow the classification of drugs into three groups, each group with its own pK/pD characteristics, which are the basis for the identification of new forms of administration of antimicrobials to optimize their efficacy (single dose, loading dose, continuous infusion) and to decrease toxicity. The appearance of new multiresistant pathogens, such as imipenem-resistant Pseudomonas aeruginosa and/or Acinetobacter baumannii, carbapenem-resistant Gram-negative bacteria harbouring carbapenemases, and vancomycin-resistant Enterococcus spp., has determined the use of new antibacterials, the reintroduction of other drugs that have been removed in the past due to toxicity or the use of combinations with in vitro synergy. Finally, pharmacoeconomic aspects should be considered for the choice of appropriate antimicrobials in the care of critically ill patients.

Impact of a multidimensional approach on ventilator-associated pneumonia rates in a hospital of Shanghai: findings of the International Nosocomial Infection Control Consortium

PURPOSE

The aim of this study was to analyze the impact of a multidimensional infection control approach on the reduction of ventilator-associated pneumonia (VAP) in intensive care units (ICUs) patients of one hospital in China.

MATERIALS AND METHODS

We conducted a before-after study from January 2005 to July 2009, which was divided into baseline (phase 1) and intervention (phase 2) periods. During phase 1, active prospective outcome surveillance of VAP was performed by applying the definitions of the Centers for Disease Control and Prevention/National Health Safety Network, and the methodology of the International Nosocomial Infection Control Consortium. During phase 2, the multidimensional approach was implemented. Ventilator-associated pneumonia rates obtained in phases 1 and 2 were compared in yearly periods.

RESULTS

We recorded data from 16,429 patients hospitalized in 3 ICUs, for a total of 74,116 ICU bed days. The VAP baseline rate was 24.1 per 1000 ventilator-days. During phase 2, the VAP rate significantly decreased to 5.7 per 1000 ventilator-days in 2009 (2009 vs 2005: relative risk, 0.31; 95% confidence interval, 0.16-0.36; P = .0001), amounting to a 79% cumulative VAP rate reduction.

CONCLUSIONS

Implementing a multidimensional infection control intervention for VAP was associated with a significant cumulative reduction in the VAP rate in our ICUs.

Variation in surgical site infection monitoring and reporting by state

OBJECTIVE

Surgical site infections (SSIs) are common, costly, and often preventable. There are no national requirements for measuring or reporting hospital SSI rates and state-level monitoring occurs with little coordination between states. We designed a study to describe the current status of SSI reporting in the United States.

METHODS

We reviewed SSI monitoring and reporting legislation in all 50 states in September 2010. Data collected included whether SSI monitoring and reporting legislation exists, if public reporting is required, how the data are accessible, and for which procedures SSI data are reported.

RESULTS

Twenty-one (42%) states have legislation for SSI monitoring and reporting. All 21 of these states require public release of findings. Of the states with legislation, eight (38%) currently have SSI data available publicly. A range of two to seven procedures were reported for SSI measurement by individual states. Eighteen (86%) states use state agency websites to make their data publicly available.

CONCLUSION

There is wide variation in state monitoring and reporting of SSI rates. Standardized reporting may be needed so that consumers can make informed health choices based on quality metrics.

A Comprehensive Intervention Associated With Reduced Surgical Site Infections Among Pediatric Cardiovascular Surgery Patients, Including Those With Delayed Closure

BACKGROUND

Surgical site infections (SSIs) cause significant morbidity and mortality in patients undergoing cardiovascular (CV) surgery. Following an increase in SSIs in this population, driven by a high rate in those with delayed closure, we implemented an intervention to reduce these infections and assessed the intervention using both population- and patient-level analyses.

METHODS

An intervention drawing from existing guidelines and targeting preoperative preparation of the patient, prophylactic antibiotics, and postoperative incision care was implemented. Special attention was paid to standardizing the care of the incision of patients with delayed closure. National Healthcare Safety Network criteria were used to prospectively identify SSIs. Population-level intervention effect was assessed using interrupted time series. To assess intervention adherence and effect in our patient population, retrospective chart review was performed on a cohort of patients undergoing cardiac procedures pre- and postintervention. Multivariate analysis was used to assess risk of SSI at the patient level.

RESULTS

Timely preoperative prophylactic antibiotic dosing increased from 60% preintervention to 92% postintervention, and redosing during prolonged surgeries increased from 5% to 79% (both, P < .001). At the population-level, a decrease of 6.7 infections per 100 surgeries per 6 months was observed directly following the intervention (P = .002). The SSI rate decreased from 40% to 0.8% (P < .001) in patients with delayed closure and from 4.3% to 1.8% (P = .02) in patients with immediate closure. In multivariate analyses, surgery prior to the intervention was the strongest predictor for SSI (incidence rate ratio, 3.98; 95% confidence interval, 1.59 to 9.97).

CONCLUSIONS

Our intervention decreased SSIs in pediatric CV surgery patients, particularly those with delayed closures.

Peripherally inserted central catheter bloodstream infection surveillance rates in an acute care setting in Saudi Arabia

BACKGROUND AND OBJECTIVE

Peripherally inserted central venous catheters (PICCs) are alternatives to short-term central venous catheters and provide intravenous access in the acute hospital setting. In this study, we describe the rate of PICC-associated bloodstream infections (BSI).

DESIGN AND SETTING

Prospective cohort study using data on PICC lines reviewed from January to December 2009.

METHODS

The infection control team was responsible for prospective BSI case findings. The infection rate was calculated per 1000 device-days.

RESULTS

During the study period, 92 PICC lines were inserted with a total of 3336 device-days of prospective surveillance. The most frequent reasons for the insertion of the PICC lines were chemotherapy (n=19, 20.7%), intravenous antimicrobial therapy (n=34, 37%), and for patients in the medical intensive care unit (ICU) (n=16, 17.4%). The overall BSI rate was 4.5/1000 PICC days. The PICC line-associated BSI rates for a specific indication were as follows: chemotherapy 6.6/1000 device-days, intravenous antimicrobial therapy 1.2/1000 device-days, medical ICU 7.3/1000 device-days, surgical ICU 4.6/1000 device-days, and total parental nutrition patients 2.4/1000 device-days (P<.001). The rates were not adjusted for patient severity of illness.

CONCLUSIONS

Our data suggest that underlying conditions and indications for the PICC line use may play an important role in the development of BSI.

An electronic catheter-associated urinary tract infection surveillance tool

OBJECTIVE

To develop and validate an electronic surveillance tool for catheter-associated urinary tract infections (CAUTIs).

DESIGN

Retrospective cohort study.

SETTING

413-bed university-affiliated urban teaching hospital.

METHODS

An electronic surveillance tool was developed for CAUTI and urinary catheter utilization based on the objective components of the National Healthcare Safety Network (NHSN) definitions including fever, urinalysis, and urine culture. Results were compared to manual chart review by an infection preventionist (IP).

RESULTS

During January and February 2010, 204 positive urine cultures (≥10(3) colony-forming units/mL) were identified in 136 patients with indwelling urinary catheters during their hospitalization. The electronic surveillance tool detected 60 CAUTI cases and 7,098 catheter-days, yielding a CAUTI incidence rate of 8.5 per 1,000 catheter-days. Urinary catheter utilization ratios (Foley-days/patient-days) were: acute care units, 0.27 (3,637 of 13,229); intensive care units, 0.77 (3,461 of 4,469); and overall, 0.40 (7,098 of 17,698). In comparison, the IP identified 59 cases by manual review with a sensitivity of 51 of 59 (86.4%), specificity 136 of 145 (93.8%), and negative predictive value of 136 of 144 (94.4%). Fever was present in 54 of 59 (91.5%) of CAUTI cases identified manually, while subjective criteria were documented in only 6 of 59 (10.2%) infections. Agreement between the electronic surveillance and manual IP review was assessed as very good (κ, 0.80; 95% confidence interval, 0.71-0.89).

CONCLUSIONS

We report an attempt at automating surveillance for CAUTI. With a high negative predictive value, the electronic tool allows for more efficient CAUTI surveillance and facilitates housewide trending of rates and catheter utilization. This approach should be validated in different patient populations.

Risk factors for coronary artery bypass graft chest surgical site infections in New York State, 2008

BACKGROUND

All hospitals in New York State (NYS) are required to report surgical site infections (SSIs) occurring after coronary artery bypass graft surgery. This report describes the risk adjustment method used by NYS for reporting hospital SSI rates, and additional methods used to explore remaining differences in infection rates.

METHODS

All patients undergoing coronary artery bypass graft surgery in NYS in 2008 were monitored for chest SSI following the National Healthcare Safety Network protocol. The NYS Cardiac Surgery Reporting System and a survey of hospital infection prevention practices provided additional risk information. Models were developed to standardize hospital-specific infection rates and to assess additional risk factors and practices.

RESULTS

The National Healthcare Safety Network risk score based on duration of surgery, American Society of Anesthesiologists score, and wound class were not highly predictive of chest SSIs. The addition of diabetes, obesity, end-stage renal disease, sex, chronic obstructive pulmonary disease, and Medicaid payer to the model improved the discrimination between procedures that resulted in SSI and those that did not by 25%. Hospital-reported infection prevention practices were not significantly related to SSI rates.

CONCLUSIONS

Additional risk factors collected using a secondary database improved the prediction of SSIs, however, there remained unexplained variation in rates between hospitals.

A prospective study of central venous catheters placed in a tertiary care Emergency Department: indications for use, infectious complications, and natural history

Despite successful efforts to improve overall central line-associated bloodstream infections (CLABSI) rates, little is known about CLABSI rates or even central venous catheter insertion practices in the Emergency Department. We sought to determine the baseline CLABSI rate for Emergency Department-inserted central venous catheters and to describe indications for placement, duration of use, and the natural history of these devices.

Frequency of outbreak investigations in US hospitals: results of a national survey of infection preventionists

BACKGROUND

A survey of infection preventionists was conducted to determine the frequency of outbreak investigations in US hospitals.

METHODS

A 2-part electronic survey was sent to Association for Professionals in Infection Control and Epidemiology, Inc, members in US hospitals in January 2010. Part 1 of the survey tool involved hospital demographics and the infection prevention/control program. Part 2 explored specific outbreak investigations allowing responses for up to 8 investigations within the previous 24 months.

RESULTS

A final sample of 822 responses was analyzed representing 386 outbreak investigations in 289 US hospitals. Nearly 60% of the outbreaks were caused by 4 organisms: norovirus (18%), Staphylococcus aureus (17%), Acinetobactor spp (14%), and Clostridium difficile (10%). Norovirus occurred most often in behavioral health and rehabilitation/long-term acute care units, whereas the other organisms occurred in medical/surgical units. Unit/department closure was reported in 22.6% of investigations and most often associated with norovirus. Outbreak investigations are triggered by unusual organisms, rate above baseline for specific site of infection, and rate above baseline for specific unit. Investigations were most frequently conducted in community/nonteaching hospitals and facilities with 201 to 300 beds. Mean number of confirmed cases was 10; mean duration was 58 days.

CONCLUSION

Norovirus is emerging as an increasingly common hospital-associated organism causing outbreaks in nonacute settings and may lead to unit/department closures.

Quality improvement interventions to prevent healthcare-associated infections in neonates and children

PURPOSE OF REVIEW

Healthcare-associated infections cause substantial harm to hospitalized neonates and children. Efforts that prevent these infections are a major focus of current patient safety initiatives. This review focuses on the reports of quality improvement interventions to prevent central line-associated bloodstream infections (CLABSIs) in neonates and children.

RECENT FINDINGS

Single-center and multicenter collaborative studies have examined the effect of quality improvement interventions to reliably implement central line insertion and maintenance bundles on CLABSI rates in neonatal and pediatric intensive care units. Quality improvement interventions were associated with reductions in CLABSI rates in neonates and children by a half or more, although many of the studies have important methodologic limitations. Studies that utilized improvement science methodologies demonstrated larger improvement effects, but required a sizable investment of institutional support and personnel time.

SUMMARY

Quality improvement interventions to reduce CLABSI are an important component of patient safety initiatives. Future studies of quality improvement interventions to reduce HAI among hospitalized neonates and children will benefit from further investigation of methods to enhance reliable implementation of evidence-based practices, factors that enable multicenter collaboratives to be more successful, and better understanding of the causes of heterogeneity in the results at different centers.

Performance, revision, and extension of the National Nosocomial Infections Surveillance system's risk index in Brazilian hospitals

OBJECTIVE

To assess the benefit of using procedure-specific alternative cutoff points for National Nosocomial Infections Surveillance (NNIS) risk index variables and of extending surgical site infection (SSI) risk prediction models with a postdischarge surveillance indicator.

DESIGN

Open, retrospective, validation cohort study.

SETTING

Five private, nonuniversity Brazilian hospitals.

PATIENTS

Consecutive inpatients operated on between January 1993 and May 2006 (other operations of the genitourinary system [n = 20,723], integumentary system [n = 12,408], or musculoskeletal system [n = 15,714] and abdominal hysterectomy [n = 11,847]).

METHODS

For each procedure category, development and validation samples were defined nonrandomly. In the development samples, alternative SSI prognostic scores were constructed using logistic regression: (i) alternative NNIS scores used NNIS risk index covariates and cutoff points but locally derived SSI risk strata and rates, (ii) revised scores used procedure-specific alternative cutoff points, and (iii) extended scores expanded revised scores with a postdischarge surveillance indicator. Performances were compared in the validation samples using calibration, discrimination, and overall performance measures.

RESULTS

The NNIS risk index showed low discrimination, inadequate calibration, and predictions with high variability. The most consistent advantage of alternative NNIS scores was regarding calibration (prevalence and dispersion components). Revised scores performed slightly better than the NNIS risk index for most procedures and measures, mainly in calibration. Extended scores clearly performed better than the NNIS risk index, irrespective of the measure or operative procedure.

CONCLUSIONS

Locally derived SSI risk strata and rates improved the NNIS risk index's calibration. Alternative cutoff points further improved the specification of the intrinsic SSI risk component. Controlling for incomplete postdischarge SSI surveillance provided consistently more accurate SSI risk adjustment.