bluuebunny/crossref_metadata_2025 huggingface dataset:
Incidence and Predictors of Surgical-Site Infections in Vietnam
Authors: Nguyen Dao , MacLeod William Bruce , Phung Dae Cam , Cong Quyet Thang , Nguyen Viet Hung , Nguyen Van Hoa , Hamer Davidson Howes
Published: February 2006

Objective:

To determine the incidence of, and risk factors for, surgical-site infections (SSIs).

Design:

Prospective observational study of all patients undergoing surgery during a 3-month period.

Setting:

Two urban hospitals in Hanoi, Vietnam.

Patients:

All 697 patients admitted for emergent and elective surgery.

Methods:

Data were collected on all patients undergoing surgery during a 3-month period at each hospital. We stratified the data by type of surgery, wound class, and Study on the Efficacy of Nosocomial Infection Control (SENIC) risk index. The analysis was done with the data sets from each hospital separately and with the combined data. The risk factors for SSI were identified using a logistic-regression model.

Results:

During the period of observation, 10.9% of 697 patients had SSI. The SSI rate was 8.3% for clean wounds, 8.6% for clean-contaminated, 12.2% for contaminated, and 43.9% for dirty wounds. The lowest rate of SSI (2.4%) was found in obstetric-gynecologic procedures and the highest rate (33.3%) in cardiothoracic operations. Using the SENIC risk index, the incidence of SSI in low-risk patients was 5.1%; for medium-risk patients, 13.5%, and high-risk patients, 24.2%. In a logistic-regression model, abdominal surgery (odds ratio [OR], 4.46;P<.01) and wound class IV (OR, 5.67;P<.01) were significant predictors of SSI. All patients were treated with prolonged courses of perioperative antibiotics. Overall infection control practices were poor as a result of deficient facilities, limited surgical instruments, and a lack of proper supplies for wound care and personal hygiene.

Conclusions:

There was a higher incidence of SSI in low-risk patients in Vietnam compared with developed countries. Excessive reliance on antimicrobial therapy as a means to limit SSI places patients at higher risk of adverse effects from treatment and also may contribute to worsening problems with antimicrobial resistance. Establishment of an infection control program with guidelines for antimicrobial use should improve the use of prophylactic antibiotics and attention to proper surgical and wound-care techniques. These interventions also should reduce the incidence of SSI and its associated morbidity and costs.
Incidence of, and Risk Factors for, Nosocomial Infections Among Hematopoietic Stem Cell Transplantation Recipients, With Impact on Procedure-Related Mortality
Authors: Marena Carlo , Zecca Marco , Carenini Maria Luisa , Bruschi Angela , Bassi Maria Luigia , Olivieri Pietro , Azzaretti Silvia , Locatelli Franco
Published: February 2006

Objectives:

To determine the incidence of, and risk factors for, nosocomial infections (NIs) occurring among hematopoietic stem cell transplantation (HSCT) recipients during hospitalization and to evaluate the impact of these NIs on patient outcome.

Design:

A two-year prospective observational study in two HSCT units.

Patients:

All patients admitted to the HSCT units between February 1997 and March 1999.

Setting:

A teaching hospital.

Methods:

After admission to the HSCT units, the patients were followed prospectively on a daily basis to collect all pertinent variables for the development of NIs.

Results:

49 NIs were identified in 34 of the 143 patients screened. The incidence of NIs and infected patients was 34.2% and 23.7%, respectively. The incidence density of NI was 8.96 per 1,000 patient-days. The most frequent NIs were bloodstream infections ([BSIs], 42.8%) and respiratory tract infections (28.6%). Other sites involved were as follows: eye (8.2%), urinary tract (6.1%), gastrointestinal tract (6.1%), skin (4.1%), ear (2%), and central venous catheter ([CVC], 2%). Because of the predominance and clinical relevance of BSIs, we examined both intrinsic and extrinsic risk factors associated with these infections. Independent risk factors for BSIs were allograft from matched unrelated or partially matched family donor, graft-versus-host disease (GVHD) prophylaxis without methotrexate (MTX), type of CVC, and duration of total parenteral nutrition. Four variables were independently associated with mortality occurring during hospitalization: culture-proven BSIs, advanced disease phase at transplant, type of transplant, and absence of MTX for GVHD prophylaxis.

Conclusions:

The study identified several factors associated with increased risk of BSIs among HSCT patients. Because BSIs are life-threatening complications for HSCT recipients, preventive measures aimed at reducing the incidence of these infections among patients given HSCT should be adopted.
Improved Compliance With Universal Precautions in the Operating Room Following an Educational Intervention
Authors: Kim Lynn E. , Jeffe Donna B. , Evanoff Bradley A. , Mutha Sunita , Freeman Brad , Fraser Victoria J.
Published: February 2006

Observation of surgical personnel in four specialties (cardio-thoracic, general, gynecologic, and orthopedic) in the operating room was performed prior to implementation of an educational intervention designed to improve compliance with Universal Precautions and at 1- and 2-years post-intervention. Use of protective eyewear and double gloving increased following the intervention, whereas the incidence of documented blood and body fluid exposures decreased.
Glove Reinforcement An Alternative to Double Gloving
Authors: Alrawi Sadir , Houshan Iyad , Satheesan Radhakrishnan , Raju Ramanathan , Cunningham Joseph , Acinapura Anthony
Published: February 2006

Gloves, worn by the surgical team to prevent transmission of infections from and to patients, are prone to tears and perforations. This study was done to determine the frequency and sites of unrecognized glove perforation during surgical procedures. The percentage of glove perforation was 14%. Of the punctures, 73% occurred in one of four contiguous locations on the glove. We recommend glove reinforcement at these locations to provide better protection, as well as to reduce the burden of double gloving.
Decontaminated Single-Use Devices: An Oxymoron That May Be Placing Patients at Risk for Cross-Contamination
Authors: Heeg Peter , Roth Klaus , Reichl Rudolf , Cogdill C. Philip , Bond Walter W.
Published: February 2006

Objective:

To determine whether reprocessed single-use devices would meet regulatory standards for sterility and meet the same materials standards as a new device.

Design:

The study included single-use and reusable biopsy forceps and papillotomes and a reusable stone retrieval basket. The suitability of these devices for cleaning and disinfection or sterilization was examined.

Methods:

Testing of cleanability was conducted on devices contaminated with technetium 99-radiolabeled human blood. Instruments were cleaned using hospital recommended practices for manual cleaning. Gamma counts per second were determined before and after cleaning to localize contaminants, which were additionally visualized using light and scanning electron microscopy. X-ray phc-toelectron spectroscopy was used to quantify contamination elements on the materials tested. Residual bioburden testing on instruments contaminated with microorganisms suspended in coagulable sheep blood was carried out to establish the efficacy of disinfection and sterilization.

Results:

All devices remained contaminated after cleaning, but single-use devices and the stone basket tended to be more heavily contaminated than reusable forceps and papillotomes. Cleaning procedures facilitated distribution of contaminants further into the lumens of the disposable forceps. Decreased concentrations of silicon and increased concentrations of carbon and nitrogen suggested that layers of silicon lubricant had been removed and contaminants were organic material. Reusable devices were effectively disinfected, but single-use devices were not Sterilization could not eliminate the challenge microorganisms completely.

Conclusions:

None of the reprocessed single-use instruments were effectively cleaned, disinfected, or sterilized. This condition may provide an opportunity for the viability of non-resistant or nosocomial organisms and viruses. Additionally, reprocessing procedures may result in material destruction of fragile devices. Cost-saving initiatives that have inspired reprocessing of single-use devices, despite the absence of data establishing the efficacy of decontamination and the durability of materials throughout reprocessing, should be pushed into the background.
Comparison of Pulsed-Field Gel Electrophoresis and Amplified Fragment-Length Polymorphism for Epidemiological Investigations of Common Nosocomial Pathogens
Authors: D'Agata Erika M.C. , Gerrits Monique M. , Tang Yi-Wei , Samore M. , Kusters Johannes G.
Published: February 2006

Objective:

To compare molecular typing by amplified fragment-length polymorphism (AFLP) analysis with pulsed-field gel electrophoresis (PFGE) with respect to the ability to differentiate between epidemiologically related and unrelated isolates of common nosocomial pathogens recovered during a period of endemicity.

Design:

Retrospective laboratory analysis.

Setting:

Tertiary-care institution.

Methods:

17 isolates ofAcinetobacter baumannii,22 isolates ofPseudomonas aeruginosa,and 22 vancomycin-resistantEnterococcus faecium(VRE) were typed by both methods.

Results:

AFLP generated comparable results to PFGE forA baumanniiandP aeruginosaisolates; both methods identified epidemiologically related and unrelated isolates. However, strain typing of VRE isolates produced discordant results between the two methods. PFGE identified 10 different strain types and differentiated between all epidemiologically related and unrelated isolates. In contrast, AFLP generated only five different strain types, three of which contained both epidemiologically related and unrelated isolates.

Conclusion:

Molecular typing by AFLP is comparable to PFGE forA baumanniiandP aeruginosaisolates. For VRE isolates, however, PFGE remains the method of choice.
Correlates of Antibiotic Use in Taiwan Hospitals
Authors: McDonald L. Clifford , Yu Hui Tzu , Yin Hsiao Chun , Hsiung Chao Agnes , Hung Chien-Ching , Ho Monto ,   Antibiotic Use Working Group
Published: February 2006

Objective:

To determine factors that correlate with increased antibiotic use among adult inpatients in Taiwan.

Design:

Retrospective survey of medical records.

Setting:

14 acute-care hospitals (8 regional hospitals, 6 medical centers) in Taiwan.

Participants:

A systematic probability sample from each hospital, totaling 663 adult inpatients who were discharged or had died in early 1999.

Measurements:

Infectious disease physicians at the 14 hospitals collected data from medical records regarding patient demographics, hospitalization, discharge diagnosis, and antibiotics received.

Results:

A total of 447 (67%) patients received antibiotics for an overall rate of 813 antibiotic-days (number of days patients received each antibiotic)/1,000 patient-days. Both the proportion of beds in intensive care units ([ICUs] Pearson correlation coefficient [r], 0.67; 95% confidence interval [CI95], 0.36-0.89;P<.01) and the proportion of patients admitted to surgical services (r,0.66; CI95, 0.20-0.88;P=.01) correlated with the mean patient rate of antibiotic-days/hospital-day (MPAUD). In contrast, we found no correlation between the proportion of patients who received antibiotics and the MPAUD. Using multiple linear regression, medical center status was the only independent predictor for increased MPAUD (regression coefficient [b], 0.15; CI95, 0.05-0.24;P<.01). There was no correlation between pooled rates of antibiotic-days/hospital-day and any hospital demographic factors. First-generation cephalosporin (39%) and aminoglycoside (24%) use accounted for the majority of antibiotic-days.

Conclusions:

Antibiotic use is greater in medical centers than in regional hospitals and appears to be independent of surgical case mix or the proportion of ICU beds. Determination of multiple, independent measures of antibiotic use may be necessary to understand the relation between antibiotic use and resistance in hospitals.
Topical Mupirocin for Eradication of MRSA Colonization With Mupirocin-Resistant Strains
Authors: Semret Makeda , Miller Mark A.
Published: February 2006

Topical mupirocin was able to interrupt colonization of 52% and 68% of methicillin-resistantStaphylococcus aureus(MRSA)-colonized patients carrying mupirocin-resistant and -sensitive strains, respectively, including 44.4% and 85.7% of those colonized only in the nares. Although a trend to decreased effectiveness was seen for clearing mupirocin-resistant MRSA this agent can decolonize many patients with resistant strains.
Experience in the Field: Assessing Quality of Health Care Reform in Canada
Authors: Birnbaum David , Millar John
Published: February 2006

The Canadian Institute for Health Information (CIHI) maintains databases to report independently on the health of Canadians and the performance of their healthcare system. CIHI recently received funding to improve indicator development for tracking quality, because in Canada we really have very few data that allow us to make comparable observations down to a regional or institution-specific interest level. We have a long way to go, and we recognize that collaboration and partnership is the only way that this development will move ahead.
Controlling Methicillin-Resistant Staphylococcus aureus: A Feedback Approach Using Annotated Statistical Process Control Charts
Authors: Curran Evonne T. , Benneyan James C. , Hood John
Published: February 2006

Objectives:

To investigate the benefit of a hospitalwide feedback program regarding methicillin-resistant Staphylococcus aureus (MRSA), using annotated statistical process control charts.

Design:

Retrospective and prospective analysis of MRSA rates using statistical process control charts.

Participants:

Twenty-four medical, medical specialty, surgical, intensive care, and cardiothoracic care wards and units at four Glasgow Royal Infirmary hospitals.

Methods:

Annotated control charts were applied to prospective and historical monthly data on MRSA cases from each ward and unit during a 46-month period from January 1997 through September 2000. Results were fed back from December 1999 and then on a regular monthly basis to medical staff, ward managers, senior managers, and hotel services.

Results:

Monthly reductions in the MRSA acquisition rate started 2 months after the introduction of the feedback program and have continued to the present time. The overall MRSA rate currently is approximately 50% lower than when the program began and has become more consistent and less variable within departments throughout Glasgow Royal Infirmary. The control charts have helped to detect rate changes and manage resources more effectively. Medical and nursing staff and managers also report that they find this the most positive form of MRSA feedback they have received.

Conclusions:

Feedback programs that provide current information to front-line staff and incorporate annotated control charts can be effective in reducing the rate of MRSA.
Stool Colonization With Vancomycin-Resistant Enterococci in Healthcare Workers and Their Households
Authors: Baran Joseph , Ramanathan Jambunathan , Riederer Kathleen M. , Khatib Riad
Published: February 2006

Objective:

To determine the prevalence of stool colonization with vancomycin-resistant enterococci (VRE) among healthcare workers (HCWs) and their families.

Design:

Prospective assessment of fecal colonization with VRE.

Setting:

A 603-bed, tertiary-care teaching hospital.

Participants:

Healthy volunteers recruited from hospital employees and their households were screened to exclude pregnancy, diabetes mellitus, immunosuppressive disorders, and recent use of antimicrobials.

Intervention:

Self-obtained stool swabs were used to obtain cultures. Isolated enterococci were screened for vancomycin resistance and species were identified. Intra-household isolates were genotyped using pulsed-field gel electrophoresis (PFGE).

Results:

The participants (n = 228; age range, 28 days to 80 years) were from 137 households with and 91 without employees who had contact with patients.Enterococcusspecies were isolated from 127 stool specimens (55.7%). VRE were detected in 12 individuals, representing 6E. casseliflavus, 5E. faecium, and 1E. gallinarum. VRE were more commonly isolated in employees who had contact with patients (5 of 52 vs 0 of 40; relative risk [RR], 1.9; 95% confidence interval [CI95], 1.5 to 2.2;P= .07) and their household members (10 of 137 vs 2 of 91; RR, 3.3; CI95, 0.7 to 14.8;P= .13). In 2 households (2 adults in a physician's household and an adult plus a child in a nurse's household) PFGE analysis demonstrated identical intra-household strains of vancomycin-resistantE. faecium.

Conclusions:

VRE colonization was found in 5.3% of screened stools and was more prevalent in HCWs who had contact with patients and their households. Identical PFGE patterns between 2 employees who had contact with patients and their household members demonstrated probable intra-household spread. Although the mode of acquisition was uncertain, the association with employees who had contact with patients suggests possible occupational sources. These findings demonstrate the spread of VRE within the household and implicate occupational risk for its acquisition.
Sensor-Operated Faucets: A Possible Source of Nosocomial Infection?
Authors: Assadian Ojan , El-Madani Nadja , Seper Edith , Mustafa Stefan , Aspöck Christoph , Koller Walter , Rotter Manfred L.
Published: February 2006

Recently, contamination of sensor-operated faucets (SOFs) withPseudomonas aeruginosawas observed. To evaluate odds ratios, we conducted a case–control study in which handle-operated faucets served as controls. No statistically significant difference inP. aeruginosacounts was observed between SOFs and regular faucets in our study (odds ratio, 0.0; 95% confidence interval, 0.0 to 39.0; two-sidedPexact = .99).
Intradermal Recombinant Hepatitis B Vaccine for Healthcare Workers Who Fail to Respond to Intramuscular Vaccine
Authors: Playford E. Geoffrey , Hogan Patrick G. , Bansal Amolak S. , Harrison Kareena , Drummond David , Looke David F. M. , Whitby Michael
Published: February 2006

Objective:

To study the humoral immune responses, safety, and tolerability of intradermal recombinant hepatitis B vaccination in healthcare workers (HCWs) nonresponsive to previous repeated intramuscular vaccination.

Design:

An open, prospective, before–after trial.

Setting:

A tertiary referral hospital and surrounding district health service in Queensland, Australia.

Participants:

Hospital and community HCWs nonresponsive to previous intramuscular hepatitis B vaccination.

Methods:

Intradermal recombinant hepatitis B vaccine was administered every second week for a maximum of 4 doses. Hepatitis B surface antibody (anti-HBs) responses were assessed 2 weeks after each dose.

Results:

Protective anti-HBs levels developed in 17 (94%) of 18 study subjects. Three doses resulted in seroconversion of all responding subjects and the highest geometric mean antibody concentration. The vaccine was well tolerated.

Conclusion:

More than 90% of previously nonresponsive HCWs responded to intradermal recombinant hepatitis B vaccine with protective anti-HBs levels.
Central Venous Catheter-Associated Bloodstream Infections in Pediatric Oncology Home Care
Authors: Shah Samir S. , Manning Mary Lou , Leahy Elizabeth , Magnusson Mark , Rheingold Susan R. , Bell Louis M.
Published: February 2006

Fifty-two pediatric oncology patients with central venous catheters (CVCs) who received home care services were studied. Gram-negative organisms were responsible for a greater proportion of CVC-associated bloodstream infections in pediatric oncology patients receiving home care than in hospitalized pediatric oncology patients.
The Cost of Antibiotic Resistance: Effect of Resistance Among Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa on Length of Hospital Stay
Authors:   The Brooklyn Antibiotic Resistance Task Force
Published: February 2006

To assess the effect of antimicrobial resistance on length of hospital stay, a case–control study compared infections due to four nosocomial pathogens. Significantly increased lengths of stay were associated with infections due to methicillin-resistant Staphylococcus aureus, extended-spectrum β-lactamase–producing Klebsiella pneumoniae, and carbapenem-resistant Acinetobacter baumannii or Pseudomonas aeruginosa. Infections with resistant pathogens are associated with prolonged hospitalization.
A Nursery Outbreak of Staphylococcus aureus Pyoderma Originating From a Nurse With Paronychia
Authors: Lo Wen-Tsung , Wang Chih-Chien , Chu Mongling
Published: February 2006

An outbreak of methicillin-susceptible Staphylococcus aureus pyoderma occurred in the nursery of a tertiary-care referral center. All strains retrieved from the outbreak, including one from a nurse's infected finger, were typed by arbitrarily primed polymerase chain reaction and automated ribotyping. The results indicated that the spread of the outbreak was probably facilitated by contamination of the nurse with paronychia.
Surveillance for Nosocomial Infections and Fever of Unknown Origin Among Adult Hematology–Oncology Patients
Authors: Engelhart Steffen , Glasmacher Axel , Exner Martin , Kramer Michael H.
Published: February 2006

Objective:

To determine the incidence of nosocomial infections (NIs) and fever of unknown origin among adult hematology–oncology patients.

Design:

Prospective surveillance study.

Setting:

The 18-bed hematology–oncology unit at the University Hospital Bonn, Bonn, Germany.

Patients:

All hematology–oncology patients admitted during a total of 8 months in 1998 and 1999.

Methods:

Standardized surveillance system based on the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance system. Rates of NI and fever of unknown origin were calculated for patient-days and patient-days at risk (ie, days with neutropenia of < 500/mm3 or leukopenia of < 1,000/mm3).

Results:

Of 116 patients hospitalized for a total of 4,002 days (172 admissions; mean length of stay, 25.2 days), 32 (27.6%) had a total of 44 documented NIs (19 bloodstream infections, 15 pneumonias, 7 urinary tract infections, and 3 others). In addition, 33 fevers of unknown origin were documented in 28 patients. No patient had thrush while receiving antifungal prophylaxis. The overall rates for NI and fever of unknown origin were 11.0 and 8.2 per 1,000 patient-days (25.3 and 15.4 per 1,000 patient-days at risk), respectively. The risks for NI and fever of unknown origin were significantly higher during neutropenic days, with 34 (77.3%) of the 44 NIs and 22 (66.7%) of the 33 fevers of unknown origin occurring during 1,345 patient-days at risk.

Conclusions:

Prospective surveillance for NIs on hematology–oncology units should include fever of unknown origin as the single most common and clinically important entity. For a meaningful comparison of surveillance data for hematology–oncology patients, the reported infection rates should include rates based on days with neutropenia, for which days with leukopenia could serve as a surrogate marker under routine conditions.
Peripheral Teflon Catheters: Factors Determining Incidence of Phlebitis and Duration of Cannulation
Authors: Cornely Oliver A. , Bethe U. , Pauls Regina , Waldschmidt D.
Published: February 2006

Background:

Catheter-related phlebitis is a frequent problem in the clinical setting. Risk factors for catheter-related phlebitis were assessed at a single tertiary-care institution where no routine change policy for peripheral intravenous catheters is in place.

Methods:

In a nonrandomized, observational trial, peripheral intravenous Teflon catheters were inserted in patients with a diagnosis of leukemia, lymphoma, solid tumor, acquired immunodeficiency syndrome, other serious infection, or autoimmune disorder. Underlying disease, age, white blood cell count at the time of insertion, physician placing the catheter, catheter bore, duration of cannulation, reason for removal of the catheter, and visual inspection of the insertion site were recorded.

Results:

Four hundred twelve catheters were inserted in 175 patients. The number of catheterizations per episode varied between 1 and 7. Three hundred sixty-four (88.3%) catheter placements were evaluable. The mean duration of cannulation was 4.2 days. The overall incidence of phlebitis was 12.9%. Catheters in leukopenic patients showed a longer duration of cannulation compared with catheters in nonleukopenic patients, but no difference regarding the phlebitis rate.

Conclusion:

Findings in this study partly contrast with data reported in the literature. In particular, leukopenia, female gender, prolonged duration of cannulation, antibiotics, and choice of insertion site could not be shown to be risk factors.
Extended-Spectrum β-Lactamase–ProducingEscherichia coliandKlebsiellaSpecies: Risk Factors for Colonization and Impact of Antimicrobial Formulary Interventions on Colonization Prevalence
Authors: Bisson Gregory , Fishman Neil O. , Patel Jean Baldus , Edelstein Paul H. , Lautenbach Ebbing
Published: February 2006

Objective:

The incidence of extended-spectrum β-lactamase (ESβL)–mediated resistance has increased markedly during the past decade. Risk factors for colonization with ESβL-producingEscherichia coliand Klebsiella species(ESβL-EK) remain unclear, as do methods to control their further emergence.

Design:

Case–control study.

Setting:

Two hospitals within a large academic health system: a 725-bed academic tertiary-care medical center and a 344-bed urban community hospital.

Patients:

Thirteen patients with ESβL-EK fecal colonization were compared with 46 randomly selected noncolonized controls.

Results:

Duration of hospitalization was the only independent risk factor for ESβL-EK colonization (odds ratio, 1.11; 95% confidence interval, 1.02 to 1.21). Of note, 8 (62%) of the patients had been admitted from another healthcare facility. In addition, there was evidence for dissemination of a singleK. oxytocaclone. Finally, the prevalence of ESβL-EK colonization decreased from 7.9% to 5.7% following restriction of third-generation cephalosporins (P= .51).

Conclusions:

ESβL-EK colonization was associated only with duration of hospitalization and there was no significant reduction following antimicrobial formulary interventions. The evidence for nosocomial spread and the high percentage of patients with ESβL-EK admitted from other sites suggest that greater emphasis must be placed on controlling the spread of such organisms within and between institutions.
Trauma Severity Scoring Systems as Predictors of Nosocomial Infection
Authors: Jamulitrat Silom , Narong Montha Na , Thongpiyapoom Somchit
Published: February 2006

Objectives:

To describe the patterns of nosocomial infections in patients with traumatic injuries and to compare the associations between injury severity, derived from various severity scoring systems, and subsequent nosocomial infections.

Design:

Prospective observational study.

Setting:

A 750-bed university hospital serving as a medical school and referral center for the southern part of Thailand.

Participants:

All trauma patients admitted to the hospital for more than 3 days during 1996 to 1999 were eligible for this study.

Methods:

The severity of injuries was measured in terms of injury severity score (ISS), revised trauma score (RTS), new injury severity score (NISS), and trauma injury severity score (TRISS). Infections acquired during hospitalization were categorized using Centers for Disease Control and Prevention criteria. The association between severity of injury and nosocomial infection was examined with Poisson regression models.

Results:

There were 222 nosocomial infections identified among 146 patients, yielding an infection rate of 0.8 infections per 100 patient-days. Surgical-site infection was the most common site-specific infection, accounting for 31.1% of all infections. The incidence of intravenous catheter–related bloodstream infection was 1.6 infections per 100 catheter-days. The bladder catheter–related urinary tract infection rate was 2.8 infections per 100 catheter-days. The rate of ventilator-associated pneumonia was 3.2 infections per 100 ventilator-days. The incidence of infection correlated well with injury severity. The infection incidence rate ratios for one severity category increment of ISS, NISS, RTS, and TRISS were 1.65 (95% confidence interval [CI95, 1.42 to 1.92), 1.79 (CI95, 1.55 to 2.05), 1.64 (CI95, 1.43 to 1.88), and 1.32 (CI95, 1.14 to 1.52), respectively.

Conclusions:

Surgical-site infection was the most common site-specific nosocomial infection. The NISS might be the most appropriate severity scoring system for adjustment of infection rates in trauma patients.
Healthcare Epidemiology is the Paradigm for Patient Safety
Authors: Scheckler William E.
Published: February 2006

I was honored to receive the 2001 Lectureship Award from the Society for Healthcare Epidemiology of America (SHEA). It was my intent during the talk to review our field and implications that some of the new initiatives called “patient safety” have for our expertise. This article is based on the SHEA Lectureship that was given April 1, 2001, at the SHEA Annual Meeting in Toronto, Ontario, Canada.

This article consists of four sections. First, I review lessons learned from colleagues during the 33 years that I have been associated with the field of hospital epidemiology and infection control, since my first days at the Centers for Disease Control and Prevention (CDC). Second, I explore issues raised by the Institute of Medicine (IOM) report on patient safety, adverse events, and medical errors, evaluating research that went into the extrapolation of the numbers of preventable deaths that this report highlighted. Those deaths gained everyone's attention. Third, I review the field of healthcare epidemiology, highlighting the three decades of success in our field in enhancing the safety of patients, improving their outcomes, and making a difference in the quality of medical care received in the United States. Finally, I discuss the challenges that hospital epidemiology currently faces and the opportunities that come with the expertise we have developed during more than 30 years.
On the reflexivity of multivariable isometries
Authors: Eschmeier Jörg
Published: February 2006

Let

A
⊂
C
(
K
)

A \subset C(K)

be a unital closed subalgebra of the algebra of all continuous functions on a compact set

K
K

in

C

n

\mathbb {C}^n

. We define the notion of an

A
A

–isometry and show that, under a suitable regularity condition needed to apply Aleksandrov’s work on the inner function problem, every

A
A

–isometry

T
∈
L
(

H

)
n

T \in L(\mathcal H)^n

is reflexive. This result applies to commuting isometries, spherical isometries, and more generally, to all subnormal tuples with normal spectrum contained in the Bergman-Shilov boundary of a strictly pseudoconvex or bounded symmetric domain.
Geometric applications of Chernoff-type estimates and a ZigZag approximation for balls
Authors: Artstein-Avidan S. , Friedland O. , Milman V.
Published: February 2006

In this paper we show that the euclidean ball of radius

1
1

in

R

n

\mathbb {R}^n

can be approximated up to

ε
>
0

\varepsilon >0

, in the Hausdorff distance, by a set defined by

N
=
C
(
ε
)
n

N = C(\varepsilon )n

linear inequalities. We call this set a ZigZag set, and it is defined to be all points in space satisfying

50
50%

or more of the inequalities. The constant we get is

C
(
ε
)
=
C
ln
⁡
(
1

/

ε
)

/

ε
2

C(\varepsilon ) = C \ln (1/\varepsilon )/\varepsilon ^2

, where

C
C

is some universal constant. This should be compared with the result of Barron and Cheang (2000), who obtained

N
=
C

n
2

/

ε
2

N = Cn^2/\varepsilon ^2

. The main ingredient in our proof is the use of Chernoff’s inequality in a geometric context. After proving the theorem, we describe several other results which can be obtained using similar methods.
ℬ(ℋ) is a free semigroup algebra
Authors: Davidson Kenneth
Published: February 2006

We provide a simplified version of a construction of Charles Read. For any

n
≥
2

n \ge 2

, there are

n
n

isometries with orthogonal ranges with the property that the nonselfadjoint weak-

∗
*

-closed algebra that they generate is all of

B

(

H

)

\mathcal {B}(\mathcal {H})

.
Fiber products, Poincaré duality and 𝐴_{∞}-ring spectra
Authors: Klein John
Published: February 2006

For a Poincaré duality space

X
d

X^d

and a map

X
→
B

X \to B

, consider the homotopy fiber product

X

×
B

X

X \times ^B X

. If

X
X

is orientable with respect to a multiplicative cohomology theory

E
E

, then, after suitably regrading, it is shown that the

E
E

-homology of

X

×
B

X

X \times ^B X

has the structure of a graded associative algebra. When

X
→
B

X \to B

is the diagonal map of a manifold

X
X

, one recovers a result of Chas and Sullivan about the homology of the unbased loop space

L
X

LX

.
On stable equivalences induced by exact functors
Authors: Liu Yuming
Published: February 2006

Let

A
A

and

B
B

be two Artin algebras with no semisimple summands. Suppose that there is a stable equivalence

α
\alpha

between

A
A

and

B
B

such that

α
\alpha

is induced by exact functors. We present a nice correspondence between indecomposable modules over

A
A

and

B
B

. As a consequence, we have the following: (1) If

A
A

is a self-injective algebra, then so is

B
B

; (2) If

A
A

and

B
B

are finite dimensional algebras over an algebraically closed field

k
k

, and if

A
A

is of finite representation type such that the Auslander-Reiten quiver of

A
A

has no oriented cycles, then

A
A

and

B
B

are Morita equivalent.
A local lifting theorem for subnormal operators
Authors: Majdak Witold , Sebestyén Zoltán , Stochel Jan , Thomson James
Published: February 2006

Criteria for the existence of lifts of operators intertwining subnormal operators are established. The main result of the paper reduces lifting questions for general subnormal operators to questions about lifts of cyclic subnormal operators. It is shown that in general the existence of local lifts (i.e. those coming from cyclic parts) for a pair of subnormal operators does not imply the existence of a global lift. However this is the case when minimal normal extensions of subnormal operators in question are star-cyclic.
An ultrafilter with property 𝜎
Authors: Shioya Masahiro
Published: February 2006

Let

κ
\kappa

be a

λ
\lambda

-supercompact cardinal. We show that

P

κ

λ

\mathcal {P}_\kappa \lambda

carries a normal ultrafilter with a property introduced by Menas. With it we give a transparent proof of Kamo’s theorem that

P

κ

λ

\mathcal {P}_\kappa \lambda

carries a normal ultrafilter with the partition property.
Spaces that admit hypercyclic operators with hypercyclic adjoints
Authors: Petersson Henrik
Published: February 2006

A continuous linear operator

T
:
X
→
X

T:X\to X

is hypercyclic if there is an

x
∈
X

x\in X

such that the orbit

{

T
n

x

}

n
≥
0

\{ T^n x\}_{n\geq 0}

is dense. A result of H. Salas shows that any infinite-dimensional separable Hilbert space admits a hypercyclic operator whose adjoint is also hypercyclic. It is a natural question to ask for what other spaces

X
X

does

L

(
X
)

\mathcal {L}(X)

contain such an operator. We prove that for any infinite-dimensional Banach space

X
X

with a shrinking symmetric basis, such as

c
0

c_0

and any

ℓ
p

\ell _p

(
1
>
p
>
∞
)

(1>p>\infty )

, there is an operator

T
:
X
→
X

T:X \to X

, where both

T
T

and

T
′

:

X
′

→

X
′

T’:X’\to X’

are hypercyclic.
The depth of the Jacobian ring of a homogeneous polynomial in three variables
Authors: Simis Aron
Published: February 2006

The question as to whether the Jacobian ideal of an irreducible projective plane curve always admits an irrelevant component has been going around for some years. One shows that a curve will satisfy this if it has only ordinary nodes or cusps, while an example is given of a family of sextic curves whose respective Jacobian ideals are saturated. The connection between this problem and the theory of homogeneous free divisors in three variables is also pointed out, so the example gives a family of Koszul-free divisors.
Poincaré duality algebras and rings of coinvariants
Authors: Lin Tzu-Chun
Published: February 2006

Letϱ:G↪GL(n,F)\varrho :G\hookrightarrow GL(n, \mathbb {F})be a faithful representation of a finite groupGGover the fieldF\mathbb {F}. Viaϱ\varrhothe groupGGacts onV=FnV=\mathbb {F} ^nand hence on the algebraF[V]{\mathbb {F}}[V]of homogenous polynomial functions on the vector spaceVV. R. Kane (1994) formulated the following result based on the work of R. Steinberg (1964): If the fieldF\mathbb {F}has characteristic00, thenF[V]G{\mathbb {F}}[V] _Gis a Poincaré duality algebra if and only ifGGis a pseudoreflection group. The purpose of this note is to extend this result to the case|G|∈F×|G|\in \mathbb {F} ^{\times }(i.e. the order|G||G|ofGGis relatively prime to the characteristic ofF\mathbb {F}).
Semi-finite forms of bilateral basic hypergeometric series
Authors: Chen William , Fu Amy
Published: February 2006

We show that several classical bilateral summation and transformation formulas have semi-finite forms. We obtain these semi-finite forms from unilateral summation and transformation formulas. Our method can be applied to derive Ramanujan’s

1

ψ

1

_{1}\psi _{1}

summation, Bailey’s

2

ψ

2

_{2}\psi _{2}

transformations, and Bailey’s

6

ψ

6

_{6}\psi _{6}

summation.
Isometries of the Dirichlet space among the composition operators
Authors: Martín María , Vukotić Dragan
Published: February 2006

We show that every composition operator which is an isometry of the Dirichlet space is induced by a univalent full map of the disk into itself that fixes the origin. This is an analogue of the Hardy space result for inner functions due to Nordgren. The proof relies on the Stone-Weierstrass theorem and the Riesz representation theorem.
Local bases for refinable spaces
Authors: Cabrelli Carlos , Heineken Sigrid , Molter Ursula
Published: February 2006

We provide a new representation of a refinable shift invariant space with a compactly supported generator, in terms of functions with a special property of homogeneity. In particular, these functions include all the homogeneous polynomials that are reproducible by the generator, which links this representation to the accuracy of the space. We completely characterize the class of homogeneous functions in the space and show that they can reproduce the generator. As a result we conclude that the homogeneous functions can be constructed from the vectors associated to the spectrum of the scale matrix (a finite square matrix with entries from the mask of the generator). Furthermore, we prove that the kernel of the transition operator has the same dimension as the kernel of this finite matrix. This relation provides an easy test for the linear independence of the integer translates of the generator. This could be potentially useful in applications to approximation theory, wavelet theory and sampling.
On the construction of frames for Triebel-Lizorkin and Besov spaces
Authors: Kyriazis George , Petrushev Pencho
Published: February 2006

We present a general method for construction of frames

{

ψ
I

}

I
∈

D

\{\psi _I\}_{I\in \mathcal {D}}

for Triebel-Lizorkin and Besov spaces, whose nature can be prescribed. In particular, our method allows for constructing frames consisting of rational functions or more general functions which are linear combinations of a fixed (small) number of shifts and dilates of a single smooth and rapidly decaying function

θ
\theta

such as the Gaussian

θ
(
x
)
=
exp
⁡
(
−

|

x

|

2

)

\theta (x)=\exp (-|x|^2)

. We also study the boundedness and invertibility of the frame operator

S
f
=

∑

I
∈

D

⟨

f
,

ψ
I

⟩

ψ
I

Sf=\sum _{I\in \mathcal {D}} \langle {f,\psi _I}\rangle \psi _I

on Triebel-Lizorkin and Besov spaces and give necessary and sufficient conditions for the dual system

{

S

−
1

ψ

}

I
∈

D

\{S^{-1}\psi \}_{I\in \mathcal {D}}

to be a frame as well.
Commutator automorphisms of formal power series rings
Authors: Gubeladze Joseph , Mushkudiani Zaza
Published: February 2006

For a big class of commutative rings

R
R

, every continuous

R
R

-automorphism of

R
[
[

X
1

,
…
,

X
n

]
]

R[[X_1,\ldots ,X_n]]

with the linear part the identity is in the commutator subgroup of

Aut
⁡
(
R
[
[

X
1

,
…
,

X
n

]
]
)

\operatorname {Aut}(R[[X_1,\ldots ,X_n]])

. An explicit bound for the number of commutators involved and a

K
K

-theoretic interpretation of this result are provided.
Uniqueness for multiple trigonometric and Walsh series with convergent rearranged square partial sums
Authors: Ash J. , Tetunashvili Sh.
Published: February 2006

If at each point of a set of positive Lebesgue measure every rearrangement of a multiple trigonometric series square converges to a finite value, then that series is the Fourier series of a function to which it converges uniformly. If there is at least one point at which every rearrangement of a multiple Walsh series square converges to a finite value, then that series is the Walsh-Fourier series of a function to which it converges uniformly.
A perturbed elementary operator and range-kernel orthogonality
Authors: Duggal B.
Published: February 2006

LetB(H)B(\mathcal {H})denote the algebra of operators on a HilbertH\mathcal {H}. IfAjA_jandBj∈B(H)B_j\in B(\mathcal {H})are commuting normal operators, andCjC_jandDj∈B(H)D_j\in B(\mathcal {H})are commuting quasi-nilpotents such that<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper A Subscript j Baseline upper C Subscript j Baseline minus upper C Subscript j Baseline upper A Subscript j Baseline equals upper B Subscript j Baseline upper D Subscript j Baseline minus upper D Subscript j Baseline upper B Subscript j Baseline equals 0">AjCj−CjAj=BjDj−DjBj=0A_jC_j-C_jA_j=B_jD_j-D_jB_j=0, then defineMj,Nj∈B(H)M_j, N_j\in B(\mathcal {H})andE,E∈B(B(H)){\mathcal E}, E\in B(B(\mathcal {H}))byMj=Aj+CjM_j=A_j+C_j,Nj=Bj+DjN_j=B_j+D_j,E(X)=A1XA2+B1XB2{\mathcal E}(X)=A_1XA_2+B_1XB_2andE(X)=M1XM2+N1XN2E(X)=M_1XM_2+N_1XN_2. It is proved that<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper E Superscript negative 1 Baseline left-parenthesis 0 right-parenthesis subset-of-or-equal-to upper H 0 left-parenthesis script upper E right-parenthesis equals script upper E Superscript negative 1 Baseline left-parenthesis 0 right-parenthesis">E−1(0)⊆H0(E)=E−1(0)E^{-1}(0)\subseteq H_0({\mathcal E})={\mathcal E}^{-1}(0)and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper X element-of upper E Superscript negative 1 Baseline left-parenthesis 0 right-parenthesis long right double arrow StartAbsoluteValue EndAbsoluteValue upper X StartAbsoluteValue EndAbsoluteValue less-than-or-equal-to k dist left-parenthesis upper X comma script upper E left-parenthesis upper B left-parenthesis script upper H right-parenthesis right-parenthesis right-parenthesis">X∈E−1(0)⟹||X||≤kdist(X,E(B(H)))X\in E^{-1}(0)\Longrightarrow ||X||\leq k \textrm {dist}(X, {\mathcal E}(B(\mathcal {H}))), wherek≥1k\geq 1is some scalar andH0(E)H_0({\mathcal E})is the quasi-nilpotent part of the operatorE{\mathcal E}.
Symmetry of solutions to some systems of integral equations
Authors: Jin Chao , Li Congming
Published: February 2006

In this paper, we study some systems of integral equations, including those related to Hardy-Littlewood-Sobolev (HLS) inequalities. We prove that, under some integrability conditions, the positive regular solutions to the systems are radially symmetric and monotone about some point. In particular, we established the radial symmetry of the solutions to the Euler-Lagrange equations associated with the classical and weighted Hardy-Littlewood-Sobolev inequality.
On Rourke’s extension of group presentations and a cyclic version of the Andrews–Curtis conjecture
Authors: Ivanov S.
Published: February 2006

In 1979, Rourke proposed to extend the set of cyclically reduced defining words of a group presentation

P

\mathcal P

by using operations of cyclic permutation, inversion and taking double products. He proved that iterations of these operations yield all cyclically reduced words of the normal closure of defining words of

P

\mathcal P

if the group, defined by the presentation

P

\mathcal P

, is trivial. We generalize this result by proving it for every group presentation

P

\mathcal P

with an obvious exception. We also introduce a new, “cyclic", version of the Andrews–Curtis conjecture and show that the original Andrews–Curtis conjecture with stabilizations is equivalent to its cyclic version.
Compensatory growth of fast‐growing willow (Salix) coppice in response to simulated large herbivore browsing
Authors: Guillet Christel , Bergström Roger
Published: February 2006

We tested the effect of timing and intensity of deer browsing on compensatory response by willow grown for bioenergy. Browsing was simulated several times during summer and once during winter. The clipping was done at different intensities during the first year after establishment in a new willow plantation, and during the first year after harvest in an older willow coppice. Total aboveground biomass and biomass available for deer browsing were recorded both at the end of the first and the second growing periods after clipping. Both in the new plantation and in the older coppice, the willows fully compensated for biomass losses after winter clipping, irrespective of clipping intensity. On the other hand, total biomass production usually decreased after high‐intensity summer clipping. Such a seasonal difference may be explained by the nutrition of remaining buds after clipping. In the new willow plantation, total produced biomass after summer clipping still bottomed at about 50% of the level of control stools at the end of the experiment. In the older coppice, usual browsing levels by deer in summer, roughly corresponding to the moderate clipping intensities used in this experiment, did not influence total produced biomass. The newly established willow stools reacted to summer clipping by undercompensating in terms of biomass available for deer browsing, while older stools could overcompensate. Compared to stools clipped in late summer, willow stools clipped during early summer were able to compensate earlier and stronger. The higher the proportion of twig biomass removed by summer clipping, the lower the compensatory growth by willow. Depending on the circumstances, the fast‐growing willows responded within the whole continuum from under‐ to overcompensation, and some implications for the management of willow plantations and large herbivores are discussed.