National Nosocomial Infections Surveillance (NNIS) semiannual report, May 1995. A report from the National Nosocomial Infections Surveillance (NNIS) System

Should the CDC's recommendations for promptly removing unnecessary centrally inserted central catheters be enhanced? Ultrasound-guided peripheral venous cannulation to fully comply

PURPOSE

In an effort to reduce catheter-related bloodstream infection's incidence rates in an intensive care unit, several evidence-based procedures recommended by the Centers for Disease Control and Prevention for centrally inserted central catheters were implemented. A failure to fully comply with the recommendation for prompt removal of the centrally inserted central catheters was attributed, mainly to the difficulties and inadequacies raised from establishing peripheral venous access.

METHODS

The ultrasound-guided peripheral venous cannulation method as a supplementary intervention to the Centers for Disease Control and Prevention's recommendations was incorporated and examined during the subsequent year.

RESULTS

A significant reduction on catheter-related bloodstream infection incidence rates out of the expected range was found. Centrally inserted central catheters utilization ratios were reduced by 10.7% (p < 0.05; 58%-47%) and the catheter-related bloodstream infection incidence rate was reduced by 11.7 per thousand device-days (15.9-4.16/1000 centrally inserted central catheters days (2015-2016 group, respectively)).

CONCLUSION

The reduction of catheter-related bloodstream infection was higher than that described in the published literature. This probably shows that the combination of the five evidence-based procedures recommended by the Centers for Disease Control and Prevention together with that of ultrasound-guided peripheral venous cannulation method can increase the compliance with the Category IA recommendation for removal or avoidance of unnecessary placement of centrally inserted central catheters and decrease the catheter-related bloodstream infections in a more effective way, by affecting the patients' centrally inserted central catheter exposure.

Twenty-five Years of Advances in Vascular Access: Bridging Research to Clinical Practice

Vascular access has become a key component for a multitude of IV therapies, including parenteral nutrition. Access of the central venous system has been long recognized for its associated complications of infection, thrombosis, and occlusion. Over the past 25 years, clinical practice based on research and innovation has attempted to decrease complication rates and therefore improve the safety of vascular access. This article highlights the research and its influence on catheter care procedures, technology, and education that has led to advances in vascular access. An improved understanding of the pathophysiology associated with catheter-related complications and an ongoing evaluation of new treatment modalities has provided clinicians today with new options for improved patient care and the ability to preserve vascular access options for patients.

Risk factors for surgical site infection following colorectal resection: a multi-institutional study

INTRODUCTION

Surgical site infection (SSI) is an infection occurring in an incisional wound within 30 days of surgery and significantly affects patients undergoing colorectal surgery. This study examined a multi-institutional dataset to determine risk factors for SSI following colorectal resection.

METHODS

Data on 386 patients who underwent colorectal resection in three institutions were accrued. Patients were identified using a prospective SSI database and hospital records. Data are presented as median (interquartile range), and logistic regression analysis was used to identify risk factors.

RESULTS

Patients (21.5%) developed a postoperative SSI. The median time to the development of SSI was 7 days (5-10). Of all infections, 67.5% were superficial, 22.9% were deep and 9.6% were organ space. In univariate analysis, an ASA grade of II (RR 0.6, CI 0.3-0.9, P = 0.019), having an elective procedure (RR 0.4, CI 0.2-0.6, P < 0.001), using a laparoscopic approach (RR 0.5, CI 0.3-0.9, P = 0.019), having a daytime procedure (RR 0.3, CI 0.1-0.7, P = 0.006) and having a clean/contaminated wound (RR 0.4, CI 0.2-0.7, P = 0.001) were associated with reduced risk of SSI. In multivariate analysis, an ASA grade of IV (RR 3.9, CI 1.1-13.7, P = 0.034), a procedure duration over 3 h (RR 4.3, CI 2.3-8.2, P < 0.001) and undergoing a panproctocolectomy (RR 6.5, CI 1.0-40.9, P = 0.044) were independent risk factors for SSI. Those who developed an SSI had a longer duration of inpatient stay (22 days [16-31] vs 15 days [10-26], P < 0.001).

CONCLUSIONS

Patients who develop an SSI have a longer duration of inpatient stay. Independent risk factors for SSI following colorectal resection include being ASA grade IV, having a procedure duration over 3 h, and undergoing a panproctocolectomy.

Risk factors for early onset of catheter-related bloodstream infection in an intensive care unit in China: a retrospective study

Background

Catheter-related bloodstream infection (CRBSI) is a life-threatening condition encountered in patients with long-term central venous catheter (CVC) indwelling. The objective was to investigate the clinical characteristics, treatment, and prognosis of CRBSI in the intensive care unit (ICU) in a Chinese center, as well as the risk factors for early CRBSI.

Material/Methods

A total of 73 CRBSI patients were retrospectively studied in relation to patients’ clinical and epidemiological data, microbiological culture, and treatment. Patients were treated at the Taizhou Hospital of Integrated Traditional Chinese and Western Medicine in Zhejiang (Zhejiang Wenlin, China) between January 2010 and December 2012.

Results

In this Chinese center, the most common pathogens were Gram-positive cocci, followed by Gram-negative bacilli and fungi. A high prevalence of antibiotic-resistant pathogens was detected, and a higher percentage of non-Candida albicans spp. was observed. Multivariate analysis showed that an acute physiology and chronic health evaluation II (APACHE II) score >20 and >3 types of underlying diseases were independent factors associated with CRBSI occurring within 14 days of CVC indwelling. Untimely CVC removal and/or inappropriate use of antibiotics led to significantly longer time to defervescence and time to negative conversion of blood culture (all P<0.05).

Conclusions

In this Chinese center, Gram-positive bacteria are predominantly detected in CRBSI. APACHE II score >20 and the presence of >3 types of diseases were associated with earlier CRBSI onset. Timely removal of CVC and appropriate use of antibiotics resulted in improved outcomes.

Postoperative hypoalbuminemia as a risk factor for surgical site infection after oral cancer surgery

OBJECTIVES

Postoperative surgical site infection (SSI) is a frequent postoperative complication in patients with oral cancer and significantly affects patient recovery and medical expenses. The aim of this study was to examine the predictors of SSI in patients undergoing major surgery for oral or oropharyngeal squamous cell carcinoma (OSCC) and to determine the relationship between perioperative albumin and the development of SSI.

SUBJECTS AND METHODS

In 337 consecutive patients who underwent clean-contaminated surgery for OSCC, serum albumin, glucose, and hemoglobin levels were perioperatively measured. Differences between the groups were examined using Fisher's exact test, Mann-Whitney U-test, and multiple logistic regression analysis.

RESULTS

Surgical site infection was detected in 88 (26.1%) patients with median time to development of 10 (2-25) days. Multiple logistic regression analysis showed that only postoperative serum albumin < 2.5 g dl(-1) was an independent variable predictive of SSI (P = 0.003). The duration of hospital stay was negatively correlated with postoperative albumin (R(2) = -0.302, P < 0.001).

CONCLUSION

Early postoperative hypoalbuminemia <2.5 g dl(-1) is an independent risk factor for the development of SSI in patients undergoing oral cancer surgery. Clinicians should be aware of the implications of postoperative hypoalbuminemia and consider more intensive postoperative care in these patients.

Real-time automatic hospital-wide surveillance of nosocomial infections and outbreaks in a large Chinese tertiary hospital

Background

We aimed to develop a real-time nosocomial infection surveillance system (RT-NISS) to monitor all nosocomial infections (NIs) and outbreaks in a Chinese comprehensive hospital to better prevent and control NIs.

Methods

The screening algorithm used in RT-NISS included microbiological reports, antibiotic usage, serological and molecular testing, imaging reports, and fever history. The system could, in real-time, identify new NIs, record data, and produce time-series reports to align NI cases.

Results

Compared with a manual survey of NIs (the gold standard), the sensitivity and specificity of RT-NISS was 98.8% (84/85) and 93.0% (827/889), with time-saving efficiencies of about 200 times. RT-NISS obtained the highest hospital-wide monthly NI rate of 2.62%, while physician and medical record reviews reported rates of 1.52% and 2.35% respectively. It took about two hours for one infection control practitioner (ICP) to deal with 70 new suspicious NI cases; there were 3,500 inpatients each day in the study hospital. The system could also provide various updated data (i.e. the daily NI rate, surgical site infection (SSI) rate) for each ward, or the entire hospital. Within 3 years of implementing RT-NISS, the ICPs monitored and successfully controlled about 30 NI clusters and 4 outbreaks at the study hospital.

Conclusions

Just like the “ICPs’ eyes”, RT-NISS was an essential and efficient tool for the day-to-day monitoring of all NIs and outbreak within the hospital; a task that would not have been accomplished through manual process.

Malnutrition and pancreatic surgery: prevalence and outcomes

BACKGROUND

Pancreatic surgery is associated with severe postoperative morbidity. Identification of patients at high risk may provide a way to allocate resources objectively and focus care on those patients in greater need. The Authors evaluate the prevalence of malnutrition and its effect on the postoperative morbidity of patients undergoing pancreatic surgery for malignant tumors.

METHODS

Data were collected from 143 patients who had undergone pancreatic resection for cancer. Prevalence of malnutrition was evaluated by several validated screening tools and correlated to the incidence of surgical site infection, overall morbidity, mortality, and hospital stay.

RESULTS

Overall, 88% of patients were at medium-high risk of malnutrition. Patients at high risk of malnutrition presented a fourfold longer postoperative hospitalization period and a higher morbidity rate (53.2%) than those patients at low risk of malnutrition. Malnutrition, evaluated by MUST and NRI, was an independent predictor of overall morbidity using multivariate analysis (P = 0.00145, HR = 2.6581, 95% CI = 1.3589-8.5698, and P = 0.07129, HR = 1.9953, 95% CI = 0.9723-13.548, respectively).

CONCLUSION

Malnutrition is a relevant predictor of post-operative morbidity and mortality after pancreatic surgery. Patients underwent pancreatic resection for malignant tumors are usually malnourished. Preoperative malnutrition screening is mandatory in order to assess the risk and to treat the malnutrition.

Serratia marcescens bacteremia because of contaminated prefilled heparin and saline syringes: a multi-state report

A national outbreak of Serratia marcescens bacteremia because of contaminated prefilled heparin and saline syringes led to their recall. We evaluated the clinical impact of this outbreak in 57 patients at 3 centers. All patients were symptomatic and were treated with intravenous antibiotics with a fatal outcome in 1 patient.

Preoperative hypoalbuminemia is an independent risk factor for the development of surgical site infection following gastrointestinal surgery: a multi-institutional study

BACKGROUND

Surgical site infection (SSI) is an infection occurring in an incisional wound within 30 days of surgery and significantly effects patient recovery and hospital resources.

OBJECTIVE

This study sought to determine the relationship between preoperative serum albumin and SSI.

METHODS

A study of 524 patients who underwent gastrointestinal surgery in 4 institutions was performed. Patients were identified using a prospective SSI database and hospital records. Serum albumin was determined preoperatively in all patients. Hypoalbuminemia was defined as albumin <30 mg/dL. Data are presented as median (interquartile range) and a difference between groups was examined using Mann-Whitney U and Fisher exact test and multiple logistic regression analysis.

RESULTS

A total of 105 patients developed a SSI (20%). The median time to the development of SSI was 7 (5-10) days. Having an emergency procedure (P = 0.003), having a procedure over 3 hours in duration (P = 0.047), being American Society of Anaesthetics grade 3 (P = 0.03) and not receiving preoperative antibiotics (P = 0.007) were associated with SSI while having a laparoscopic procedure reduced the likelihood of SSI (P = 0.004). Patients who developed a SSI had a lower preoperative serum albumin (30 [25-34.5] vs. 36 [32-39], P < 0.001). On multivariate analysis, hypoalbuminemia was an independent risk factor for SSI development (relative risk, RR = 5.68, 95% confidence interval: 3.45-9.35, P < 0.001). Albumin <30 mg/dL was associated with an increased rate of deep versus superficial SSI (P = 0.002). The duration of inpatient stay was negatively correlated with preoperative albumin (R = -0.319, P < 0.001).

CONCLUSIONS

Hypoalbuminemia is an independent risk factor for the development of SSI following gastrointestinal surgery and is associated with deeper SSI and prolonged inpatient stay.

The prevalence of meticillin-resistant Staphylococcus aureus in long-term care facilities: is there a need for tailored glycopeptide prophylaxis?

Prophylactic antibiotics are effective in reducing the rate of surgical site infection (SSI). Cephalosporin antibiotics are recommended except for patients colonised with meticillin resistant staphylococcus aureus (MRSA), where glycopeptide antibiotics are indicated. However, in the trauma setting, the MRSA status is unknown prior to surgery.

Aim: To determine if the incidence of MRSA colonisation in trauma patients from long term care (LTC) warrants the use of empirical glycopeptide antibiotics.

Methods: A retrospective analysis of patients admitted with hip fractures was performed. The MRSA status of patient from LTC facilities and home was determined.

Results: The prevalence of MRSA colonisation in patients admitted from LTC facilities was 33.6%, compared to 3.6% for patients admitted from home, P < 0.001.

Our results suggest that risk of patients carrying MRSA is significantly higher for patients being admitted form LTC. This group of patients may benefit from empirical glycopeptide antibiotic when the MRSA status is unknown.

Translating infection prevention evidence into practice using quantitative and qualitative research

Infection control professionals and hospital epidemiologists, using the valid methods of applied epidemiology-surveillance, benchmarking, intervention, evaluation--have largely been responsible for dramatically reducing the incidence of health care-associated infections over the past several decades. However, we believe that the field of infection control can--and should--also be a leader in understanding how research findings can be efficiently and effectively translated into clinical practice. Unfortunately, there is no current reliable information about which preventive practices are being used in US hospitals to prevent common device-related infections. If we are to understand how best to translate research into practice, the reasons hospitals are using some preventive practices-or are not-must be explored more fully. This article provides a framework for one proposed research endeavor to promote the successful translation of proven infection prevention practices and a subsequent decrease in health care-associated infections. In addition, we hope that this article will stimulate increased interest and research in identifying strategies that will successfully move evidence from the peer-reviewed literature to the patient's bedside.

Duration of operation as a risk factor for surgical site infection: comparison of English and US data

T times are used to categorize surgical procedures into long and short durations. They constitute a part of the US National Nosocomial Infection Surveillance (NNIS) risk index that is widely used internationally in surveillance for surgical site infections (SSIs). The objective of this study was to compare the US NNIS T times with data collected in England. The Surgical Site Infection Surveillance Service in England holds data collected by 168 hospitals in 13 categories of surgical procedures between 1997 and 2002. The 75(th) percentile and corresponding T time were calculated from English data and compared with US times. Differences in rates of SSI above and below the T times were compared. Graphical methods were used to assess the cut points that exhibited an association with risk of SSI. The results show that English and US T times were the same for all surgical categories except coronary artery bypass graft and vascular surgery, where the English T time was 4 h. The 75(th) percentile time for hip hemiarthroplasties was 40 min less than for total hip replacements (THR). Although the incidence of SSI in THR was significantly higher in operations lasting for longer than the T time (P<0.05), no association between risk of SSI and T times set at 1, 1.5 or 2 h was observed for hip hemiarthroplasties. In conclusion, operations lasting for longer than the T time were associated with a higher risk of SSI in most categories. In the hip prosthesis category, this association only applied to THR.

Evidence-Based Practice to Reduce Central Line Infections

BACKGROUND

In 2003, through the Greater Cincinnati Health Council nine health care systems agreed to participate and fund 50% of a two-year project to reduce hospital-acquired infections among patients in intensive care units (ICU) and following surgery (SIP).

METHODS

Hospitals were randomized to either the CR-BSI or SIP project in the first year, adding the alternative project in year 2. Project leaders, often the infection control professionals, implemented evidence-based practices to reduce catheter-related blood stream infections (CR-BSIs; maximal sterile barriers, chlorhexidine) at their hospitals using a collaborative approach. Team leaders entered process information in a secure deidentifled Web-based database.

RESULTS

Of the four initial sites randomized to CR-BSI reduction, all reduced central line infections by 50% (CR-BSI, 1.7 to 0.4/1000 line days, p < .05). At the project midpoint (3 quarters of 2004), adherence to evidence-based practices increased from 30% to nearly 95%.

DISCUSSION

The direct role of hospital leadership and development of a local community of practice, facilitated cooperation of physicians, problem solving, and success. Use of forcing functions (removal of betadine in kits, creation of an accessory pack and a checklist for line insertion) improved reliability. The appropriate floor for central line infections in ICUs is < 1 infection /1,000 line days.

The prevalence study of hospital-acquired infections at different surgical departments in Banjaluka

Introduction: Prevalence study is simple, cheap and fast method that provides information about hospital-acquired infections (HAI). Objective: To assess the HAI prevalence at different surgical departments in the Clinical Center of Banjaluka. Method: A point prevalence study design was used. All patients (N = 174) hospitalized on July, 1st, 1999 were included in the study. The study was performed by following the CDC guidelines. All patients with clinically manifested infections on the day of study in all surgical departments were recorded. Infections of more than one site in the same patient were considered separate infections. Results: The overall prevalence of patients with HAI was 16.1% (28/174; 95%CI = 10.4-21.6) and the overall HAI prevalence was 18.4% (32/174). Surgical-site infections were the most prevalent (6.3%) followed by skin/soft tissue infections (4.6%) and urinary tract infections (4.0%). More than two thirds (87.5%) of HAI were microbiologically documented. The most commonly isolated microorganisms were Pseudomonas aeruginosa (29.7%), Enterobacter spp. (24.3%) and Staphylococcus aureus (16.2%). Conclusion: This point prevalence study clearly showed the magnitude of HAI problem at different surgical departments in the Clinical Center of Banjaluka, the most prevalent anatomic localizations of HAI, and the most common causes.

Vancomycin-resistant enterococci: 15 years and counting

We review the history of vancomycin-resistant enterococci (VRE) and propose a causal model illustrating the roles of exposure to VRE reservoirs, patient characteristics, antimicrobial exposure, and prevalence of VRE in the progression from potential VRE reservoirs to active disease in hospitalized patients. Differences in VRE colonization and VRE infection are discussed with respect to hospital surveillance methodology and implications for interventions. We further document clonal transmission of VRE in a large, urban, teaching hospital and demonstrate VRE susceptibility to a wide array of antimicrobial agents. This model can guide the identification of mutable factors that are focal points for intervention.

Clinical resistance encountered in the respiratory surveillance program (RESP) study: a review of the implications for the treatment of community-acquired respiratory tract infections

The Respiratory Surveillance Program (RESP) is a large-scale surveillance study of potential bacterial pathogens from respiratory tract infections that was performed over a 10-month period (July to April) during the 1999-2000 respiratory infection season. It is also the first study of its kind to derive its information entirely from community-based medical practices. This study, therefore, provides insight into the identity, frequency, and susceptibility of the possible pathogens isolated from patients encountered by primary care physicians. Reduction of antibiotic susceptibility in various bacterial pathogens may be of academic interest. However, it is only the emergence of clinical resistance (strains exhibiting minimum inhibitory concentrations above the resistance breakpoint) to commonly used antibacterial agents in the most prevalent species that has significant impact on empiric therapy choices. A review of data from RESP indicated that the most prevalent species were Moraxella catarrhalis, Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae. As expected, the prevalence of these bacterial isolates varied by disease state. The prevalence of clinical resistance to various antibiotics ranged, within these 4 species, between 0% and 92%. Resistance to the greatest number of drugs was expressed by S pneumoniae, followed by S aureus, H influenzae, and M catarrhalis. The prevalence of antibiotic resistance found among these community-isolated pathogens was surprisingly similar to that reported in hospital-based studies, suggesting that resistance is as important an issue in the community as it is in hospitals. With few exceptions, the prevalence of resistance was fairly uniform across disease states. The antibiotics most likely to encounter clinically resistant isolates during the treatment of community-acquired respiratory tract infections were penicillins, macrolides, and trimethoprim/sulfamethoxazole. The antibiotics least likely to encounter resistance were quinolones, followed by ceftriaxone and amoxicillin/clavulanate.

Complications in tunneled CVL versus PICC lines in very low birth weight infants

OBJECTIVE

Comparison of complications associated with tunneled central venous lines (TCVLs) versus peripherally inserted central catheters (PICCs) in infants <1500 g.

STUDY DESIGN

A retrospective cohort study at a university medical center. A total of 96 catheters were placed in 60 infants between 4/94 and 3/99. A retrospective review of these infants' medical record was done to review associated complications of catheter placement.

RESULTS

Both groups had similar weights and gestational ages. The duration of catheterization was 28 days in TCVLs and 11 days in PICCs (p<0.05). Total, infectious, and mechanical complications between the two groups were similar. Survival function estimates showed no difference between the two groups up to the 15th day of catheterization.

CONCLUSION

There is no difference in efficacy or associated complications between the two groups. If one could anticipate needing a catheter longer than 15 days, then a TCVL might be the better choice.

The role of gown and glove isolation and strict handwashing in the reduction of nosocomial infection in children with solid organ transplantation

OBJECTIVE

Nosocomial infection is an important contributor to morbidity and mortality in pediatric solid organ transplantation. The relative effect of protective gown and glove isolation was compared with strict handwashing in pediatric intensive care unit (PICU) patients with solid organ transplantation.

DESIGN/SETTING

A prospective, randomized design was used; children in a 23-bed PICU with solid organ transplantation were enrolled into a gown and glove protective isolation protocol or a strict handwashing protocol.

PATIENTS

All children admitted to the PICU immediately after solid organ transplantation, excluding renal transplantation, and at subsequent readmissions to the PICU were eligible for the study. Children with current infection or known exposure to varicella were excluded from the study initially or at readmission.

INTERVENTIONS

By using a block randomization design based on organ transplanted, age, and initial admission vs. readmission, each patient was randomized to either strict handwashing or protective gown and glove isolation intervention groups.

MEASUREMENTS

We analyzed demographics, infection outcomes (defined according to Centers for Disease Control criteria), and monitoring of patient contacts in compliance with protocols.

RESULTS

The infection rate in the overall PICU population did not change significantly from the year before the study compared with during the study (2.1 per 100 vs. 1.95 per 100 patient days; p =.4) The infection rate in the gown and glove group (2.3 per 100 patient days) was reduced significantly compared with the prestudy infection rate in the transplant population (4.9 per 100 patient days; p =.0008). Strict handwashing also significantly reduced the infection rate in the transplant population (3.0 per 100 patient days; p =.008). Compliance with gowning and gloving was 82% and compliance with handwashing was 76% (compared with 22% before study [p <.0001] and 52% after the study [p <.0001]). Despite an increased mean length of stay in the PICU in the gown and glove group (p =.014), there was a trend toward reduction in the incidence of infection (Fisher's exact test, p =.07; odds ratio,.76) in the gown and glove group.

CONCLUSIONS

Increased compliance with handwashing was associated with a reduction in nosocomial infections, and gown and glove isolation appeared to have an additional protective effect. Some nosocomial infections may be preventable in the pediatric solid organ transplantation population.

Multicenter surveillance study for nosocomial infections in major hospitals in Korea. Nosocomial Infection Surveillance Committee of the Korean Society for Nosocomial Infection Control

BACKGROUND

The goals of a surveillance for nosocomial infections (NIs) are to observe the magnitude and characteristics of NIs and to plan and evaluate policies and guidelines of infection control. This study was designed to determine the rate and distribution of NIs and their causative pathogens in Korean hospitals.

METHODS

Prospective surveillance was performed at 15 acute care hospitals with more than 500 beds during a 3-month period from June to August 1996. The case-finding methods were laboratory-based surveillance for patients in the general wards and a direct review of medical charts done regularly for all the patients in the intensive care units.

RESULTS

A total of 3162 NIs were found among 85,547 discharged patients, with an overall nosocomial infection rate of 3.70 per 100 patients discharged. Urinary tract infections constituted 30.3% of all NIs. Other infections were pneumonias, 17.2%, surgical site infections, 15.5%, and primary bloodstream infections, 14.5%. The infection rate was the highest in neurosurgery (14.21), followed by neurology (8. 62) and ontology services (6.70). The infection rate in intensive care units was higher than it was in the general wards (10.74 vs 2. 57, P =.001). The commonly isolated organisms were Staphylococcus aureus (17.2%), Pseudomonas aeruginosa (13.8%), and Escherichia coli (12.3%).

CONCLUSIONS

This first multicenter surveillance study provided extensive information on the current status and trends of NIs in major hospitals in Korea. The results may contribute to the evaluation of infection control programs and the development of effective strategies in these hospitals.

Nosocomial infections in the intensive care units at a university hospital in a developing country: comparison with National Nosocomial Infections Surveillance intensive care unit rates

OBJECTIVE

As a measure of the quality of care provided to patients in the intensive care unit, comparison of nosocomial infection rates with those of the National Nosocomial Infection surveillance was completed during a 3-year observation period.

DESIGN

The study design was a prospective study during 3 years between 1993 and 1995. During that period, patients at the medical/surgical and neurosurgical intensive care units and the high-risk nursery were surveyed for nosocomial infections. Device use, bloodstream infection, urinary tract infection, and ventilator-associated pneumonia nosocomial infection rates were calculated and compared with the National Nosocomial Infection Surveillance published rates for the same period.

SETTING

The study setting was the medical/surgical intensive care unit, the neurosurgical intensive care unit, and the high-risk nursery at the Jordan University Hospital.

RESULTS

Overall infection rates were 17.2 per 100 patients in the medical/surgical intensive care unit, 14.2 to 18.5 per 100 patients in the neurosurgical intensive care unit, and 13.4 to 73.5 per 100 patients in the high-risk nursery. When compared with the weight of the infants, these rates were 61.9 to 94 per 100 in infants weighing <1500 g, 26 to 30.8 per 100 patients in infants weighing >1500 g to 2500 g, and 11.7 to 14.4 per 100 in infants weighing >2500 g. Whereas device use was moderate, bloodstream infection and ventilator-associated pneumonia rates were >90th percentile for National Nosocomial Infection Surveillance in the high-risk nursery, and urinary tract infection was >90th percentile in the medical/surgical and neurosurgical intensive care units. Nosocomial infections at the intensive care units in developing countries need further investigation and control.

Implementation of an interactive computer-assisted infection monitoring program at the bedside

A new computer-assisted infection monitoring (CAI) software program has been developed for use in an intensive-care unit (ICU). By means of an interactive dialogue with physicians at the bedside, infection diagnoses and therapeutic decisions were recorded prospectively during a 3-month test period. By linking epidemiological data with information about therapeutic decisions, CAI could assess the quality of the therapeutic decisions. Antibiotics chosen empirically before the availability of any culture results, matched the antibiotic susceptibility patterns of the subsequently identified pathogens in 74% of the cases. Therapy chosen in collaboration with the computer after the pathogen was known, but before sensitivity results were available, corresponded with the eventual antibiograms of the microorganisms in 90% of the cases. Data analysis by CAI allowed us to assess critically the diagnostic and therapeutic habits in our ICU. Using the query-by-example method, CAI automatically calculated device-associated infection rates.

Comparing Nosocomial Infection Rates Among Surgical Intensive-Care Units: The Importance of Separating Cardiothoracic and General Surgery Intensive-Care Units

Among surgical intensive-care units (ICUs), we assessed differences in risk-adjusted nosocomial infection rates between cardiothoracic (CT) and general surgery ICUs, using National Nosocomial Infection Surveillance data from 1987 to 1995. Device-associated rates and average length of stay were significantly lower in CT ICUs. Comparisons of risk-adjusted nosocomial infection rates among CT ICUs should be made separately from rates from general surgery ICUs.

Asking residents about adverse events in a computer dialogue: how accurate are they?

BACKGROUND

Although retrospective identification of adverse events is time-consuming, whether they are present and/or expected is often readily apparent to providers during the provision of care.

METHODS

A computer program to flag admissions with possible adverse events was developed. Readmissions to the hospital within 31 days and admissions including more than one visit to the operating room (OR) were flagged. For surgical site infections, all admissions--including a visit to the OR--were flagged, but only a sample was evaluated in the reliability assessment. Residents in an urban, tertiary care hospital were questioned when inputting computerized discharge orders regarding adverse events among 391 cases sampled from 6,813 admissions for a two-month period.

RESULTS

For the 228 readmissions (3.3% of all admissions) identified by the computer program, resident responses had a sensitivity of 57% and a specificity of 73% in detecting an unexpected readmission (nurse responses, 96% and 91%). For the 79 patients with a return to the OR, the residents' responses had a sensitivity of 86% and a specificity of 84% for detecting an unexpected return (versus 75% and 98% for the nurses' responses). For the 209 patients with an OR visit, the sensitivity and specificity for a surgical site infection were 85% and 98% for the residents and 54% and 99% for the nurses.

DISCUSSION

Information systems can be used to screen for adverse events and to ask providers whether adverse events are unexpected, although the reliability of this approach is likely to vary by event type.

Ventilator-associated pneumonia and frequency of circuit changes

BACKGROUND

The purpose of this research was to determine whether changing tubing circuits for mechanical ventilation less often than every 48 hours would allow maintenance of acceptably low rates for ventilator-associated pneumonia.

METHODS

A computer search of the MEDLINE database from 1986 through 1996 was performed, and abstracts for 1992 through 1996 from the annual meetings of the Association for Professionals in Infection Control and Epidemiology and the Society for Healthcare Epidemiology of America were examined.

RESULTS

Eight studies indicate that the interval between ventilator tubing circuit changes can be extended to 7 days without increasing the rate of ventilator-associated pneumonia. Furthermore, the rate can be maintained at or below 10 pneumonias per 1000 ventilator-days, the approximate median of the National Nosocomial Infections Surveillance System. There is very little evidence to suggest that these circuits can safely be changed at longer intervals.

CONCLUSIONS

The weight of the evidence indicates that breathing circuits should be changed every 7 days. This practice of routine changes should be abandoned only if additional studies demonstrate that prolonged use of the same breathing circuit is associated with low rates of ventilator-associated pneumonia.

A prospective, randomized comparison of an in-line heat moisture exchange filter and heated wire humidifiers: rates of ventilator-associated early-onset (community-acquired) or late-onset (hospital-acquired) pneumonia and incidence of endotracheal tube occlusion

PURPOSE

To compare the performance of an in-line heat moisture exchanging filter (HMEF) (Pall BB-100; Pall Corporation; East Hills, NY) to a conventional heated wire humidifier (H-wH) (Marquest Medical Products Inc., Englewood, Colo) in the mechanical ventilator circuit on the incidence of ventilator-associated pneumonia (VAP) and the rate of endotracheal tube occlusion.

METHODS

This report describes a prospective, randomized trial of 280 consecutive trauma patients in a 20-bed trauma ICU (TICU). All intubated patients not ventilated elsewhere in the medical center prior to their TICU admission were randomized to either an in-line HMEF or a H-wH in the breathing circuit. Ventilator circuits were changed routinely every 7 days, and closed system suction catheters were changed every 3 days. HMEFs were changed every 24 h, or more frequently if necessary. A specific endotracheal tube suction and lavage protocol was not employed. Patients were dropped from the HMEF group if the filter was changed more than three times a day or the patient was placed on a regimen of ultra high-frequency ventilation. The Centers for Disease Control and Prevention (CDC) criteria for diagnosis of pneumonia were used; early-onset, community-acquired pneumonia was defined if CDC criteria were met in < or =3 days, and late-onset, hospital-acquired pneumonia was defined if criteria were met in >3 days. Laboratory and chest radiograph interpretation were blinded.

RESULTS

The patient ages ranged from 15 to 95 years in the HMEF group and 16 to 87 years in the H-wH group (p=not significant), with a mean age of 46 years and 48 years, respectively. The male to female ratio ranged between 78 to 82%/22 to 18%, respectively, and 55% of all admissions were related to blunt trauma, 40% secondary to penetrating trauma, and 5% to major burns. There was no difference in Injury Severity Score (ISS) between the two groups. Moreover, there was no significant difference in mean ISS among those who did not develop pneumonia and those patients who developed either early-onset, community-acquired or late-onset, hospital-acquired pneumonia. The HMEF nosocomial VAP rate was 6% compared to 16% for the H-wH group (p<0.05), and total ventilator circuit costs (per group) were reduced. There were no differences in duration of ventilation (mean+/-SD) if the patient did not develop pneumonia or if the patient developed an early-onset, community-acquired or a late-onset, hospital-acquired pneumonia. Moreover, total TICU days were reduced in the HMEF group. In addition, the incidence of partial endotracheal tube occlusion was not significantly different between the H-wH and the HMEF groups.

CONCLUSIONS

The HMEF used in this study reduced the incidence of late-onset, hospital-acquired VAP, but not early-onset, community-acquired VAP, compared to the conventional H-wH circuit. This was associated with a significant reduction in total ICU stay. Disposable ventilator circuit costs in the HMEF group were reduced compared to the H-wH group in whom circuit changes occurred at 7-day intervals.

CLINICAL IMPLICATIONS

The use of the HMEF is a cost-effective clinical practice associated with fewer late-onset, hospital-acquired VAPs, and should result in improved resource allocation and utilization.

Applying the Centers for Disease Control and Prevention and National Nosocomial Surveillance system methods in Brazilian hospitals

BACKGROUND

Nosocomial infection is an important public health problem in Brazil. The better to understand and address this problem, we began using the National Nosocomial Infection Surveillance (NNIS) system in five Brazilian hospitals in 1991.

METHODS

Data were collected prospectively according to the NNIS protocol, by using nosocomial infection definitions from the Centers for Disease Control and Prevention.

RESULTS

From January 1991 to June 1995, the overall nosocomial infection rate was 5.1% or 9.7 nosocomial infections/1000 patient-days. From the detailed epidemiologic information obtained by using the NNIS methods, interventions were designed and implemented that have reduced specific nosocomial infection rates. For example, the incidence of infection caused by methicillin-resistant Staphylococcus aureus was reduced from 0.61 infections/1000 patient-days in 1991 to 0.05 infections/1000 patient-days in 1996 (p < 0.01). The surgical site infection rate after cesarean section was reduced from 11.6% in 1993 to 5.9% in 1996 (p < 0.05). Cost savings from a program to optimize the use of antimicrobial agents in one hospital was more than $1.8 million over a 45-month period.

CONCLUSION

The NNIS method was applicable in a wide variety of hospitals, even those with little or no experience with nosocomial infection surveillance. By using this method, we defined the detailed epidemiology of nosocomial infection and implemented interventions that have significantly reduced nosocomial infection rates while achieving substantial cost savings.

Magnitude and prevention of nosocomial infections in the intensive care unit

Nosocomial infections among intensive care unit (ICU) patients usually are related to the use of invasive devices (e.g., mechanical ventilators, urinary catheters, or central venous catheters). This article discusses the impact of these devices and other risk factors for nosocomial infection in ICU patients. Data on etiologic pathogens and device-related infection rates from the National Nosocomial Infection Surveillance System are presented, general infection control guidelines for ICUs are reviewed, and special infection control problems encountered in ICUs are discussed.

Nosocomial infections in pediatric patients with burns

BACKGROUND

Nosocomial infections (NI) are believed to occur more commonly in patients with burns than in patients undergoing surgery, but benchmark rates have not been well described, and widely accepted definitions of NI in patients with burns are not available. We present a clinically useful set of definitions for NI for the pediatric burn population and provide benchmark infection rates for NI at selected sites.

METHODS

Centers for Disease Control and Prevention definitions were modified to more accurately describe nosocomial burn infection and secondary bloodstream infections (BSI) in the burn population. A surveillance system was developed and included calculation of NI rates by 1000 patient or device days, stratified into one of three risk groups (< 30% burn injury, 30% to 60% burn injury, and > 60% burn injury). All patients with acute burns admitted from January 1990 to December 1991 were included, and NI rates were calculated for burn infection, primary and secondary BSI, ventilator-related pneumonia and urinary catheter-related urinary tract infection (UTI).

RESULTS

Overall 12.5% of patients with central venous catheters had development of primary BSI for a rate of 4.9/1000 central venous catheter-days. Incidence of secondary BSI was 5.8% of patients for a rate of 5.3/1000 patient-days. Incidence of burn infection was 10.1% of patients for a rate of 5.6/1000 patient-days. Incidence of ventilator-related pneumonia was 17.5% of patients for a rate of 11.4/1000 ventilator-days. Incidence of urinary catheter-related UTI was 17.9% of patients, for a rate of 13.2/1000 urinary catheter-days. When rates were stratified by risk groups, incidence increased with increasing burn size for secondary BSI (p < or = 0.0001) and urinary catheter-related UTI (p = 0.08), although rates based on number of patient-days or device-days more accurately reflected risk of infection over time.

CONCLUSIONS

Infection remains a cause of significant morbidity and death for patients with burns. The definitions and benchmark rates reported here may be useful in evaluation of NI surveillance strategies and calculation of infection rates, which could then be used to evaluate current treatment modalities and improve outcomes for the burn population.

Femoral venous access is safe in burned children: an analysis of 224 catheters

OBJECTIVE

To document the incidence of septic and mechanical complications associated with femoral venous catheters in a subgroup of patients thought to be at particularly high risk of both: young children with large burns.

DESIGN

An analysis of data collected prospectively on all femoral venous catheters placed during a 4-year period at a regional pediatric burn facility.

RESULTS

There were 224 femoral catheters placed in 86 children with an average age of 5.3 +/- 5.1 years and an average burn size of 38% +/- 23%. Catheters were left in place for a mean duration of 5.7 days. Catheter-related sepsis occurred with 4.9% of the catheters, and mechanical complications occurred in 3.5% of the patients. There was no statistically significant association between the risk of catheter sepsis and the placement of catheters through burned versus unburned skin. Similarly, the risk of sepsis was equivalent between lines placed over a guide wire and those placed of a new site.

CONCLUSION

Femoral venous catheters are safe in burned children and are associated with a low incidence of infectious and mechanical complications.

Risk-stratified nosocomial infection surveillance in a neonatal intensive care unit: report on 24 months of surveillance

OBJECTIVE

To document the nosocomial infection rate in a single neonatal intensive care unit (NICU) in terms of patient workload and device utilization.

METHODOLOGY

Nosocomial infections have been identified and documented by the methodology described by the National Nosocomial Infection Surveillance System (NNIS), Centres for Disease Control, Atlanta. In addition, antibiotic usage has been surveyed in the NICU and standardized measures of patient exposure to antibiotics stratified by birthweight and gestational age have been described.

RESULTS

Overall nosocomial infection rates compared favourably with the published NNIS figures at 6.2 infections per 100 admissions or 4.8 per 1000 patient days. Infection rates were significantly higher in lower birthweight groups. Device-related infection rates in each birthweight cohort were also very close to published figures and varied less with birthweight group. Antibiotic exposure averaged 12% of total admission days, less than previously published data.

CONCLUSIONS

The NNIS system is applicable to Australian NICU and provides an effective tool for monitoring infection episodes.

Improving hospital-acquired infection rates: the CDC experience

BACKGROUND

The National Nosocomial Infections Surveillance (NNIS) System, begun in 1970 by the Centers for Disease Control to collect data on hospital-acquired infections, is one of the oldest continuously operating clinical performance indicator systems in the United States. Growth of the system, from 19 to 230 hospitals, has been accompanied by developments such as the evolution from hospitalwide to targeted surveillance, improved data processing and telecommunications for data collection and reporting, and risk adjustment.

ELEMENTS OF A SUCCESSFUL SYSTEM

The NNIS System provides specific, standardized methods for data collection and uses device-associated, device-day rates to risk adjust the data and make it meaningful for interhospital comparison. The system has been used as a tool for improving quality of care through prevention of nosocomial infections. For example, an 800-bed teaching hospital's rate of ventilator-associated nosocomial pneumonia in the surgical intensive care unit-49.5 infections per 1,000 ventilator days-was in excess of the 90th percentile. Improvements in care, including changing tubing and cascades every 48 hours and Ambu bags every 24 hours, as well as increased clinical evaluation of patients, was followed 12 months later by a decrease to 25.8 infections, well below the 90th percentile.

INFORMATION DISSEMINATION

Since 1992, staff from NNIS hospitals have met in a biennial conference to learn about advances in nosocomial infection surveillance and to share information with one another on infection control and quality improvement programs.

CONCLUSIONS

The NNIS experience can be used as a source of guidance for assessing the effectiveness and utility of other indicator systems.