Clinical relevance and effect of surgical wound classification in appendicitis: Retrospective evaluation of wound classification discrepancies between surgeons, Swissnoso-trained infection control nurse, and histology as well as surgical site infection rates by wound class

BACKGROUND

Surgical wound classification (SWC) is used for risk stratification of surgical site infection (SSI) and serves as the basis for measuring quality of care. The objective was to examine the accuracy and reliability of SWC. This study was purposed to evaluate the discrepancies in SWC as assessed by three groups: surgeons, an infection control nurse, and histopathologic evaluation. The secondary aim was to compare the risk-stratified SSI rates using the different SWC methods for 30 d postoperatively.

METHODS

An analysis was performed of the appendectomies from January 2013 to June 2014 in the Cantonal Hospital of Schaffhausen. SWC was assigned by the operating surgeon at the end of the procedure and retrospectively reviewed by a Swissnoso-trained infection control nurse after reading the operative and pathology report. The level of agreement among the three different SWC assessment groups was determined using kappa statistic. SSI rates were analyzed using a chi-square test.

RESULTS

In 246 evaluated cases, the kappa scores for interrater reliability among the SWC assessments across the three groups ranged from 0.05 to 0.2 signifying slight agreement between the groups. SSIs were more frequently associated with trained infection control nurse-assigned SWC than with surgeons based SWC.

CONCLUSIONS

Our study demonstrated a considerable discordance in the SWC assessments performed by the three groups. Unfortunately, the currently practiced SWC system suffers from ambiguity in definition and/or implementation of these definitions is not clearly stated. This lack of reliability is problematic and may lead to inappropriate comparisons within and between hospitals and surgeons.

Methicillin-ResistantStaphylococcus aureusEpidemiology and Control in Belgian Hospitals, 1991 to 1995

Objectives:To describe the Belgian methicillin-resis-tantStaphylococcus aureus(MRSA) surveillance network, the evolution of methods used in Belgian hospitals for MRSA detection and control, and MRSA incidence from 1994 to1995.

Design, Setting, and Participants:Questionnaire surveys; infection control physicians from acute-care hospitals in Belgium.

Intervention:Publication of national guidelines for MRSA control in 1993.

Results:The participation rate in surveys ranged from 42% to 57% of hospitals. In 1995, 88% of participants detected MRSA strains by disk diffusion tests, with little improvement in standardization since 1991. More centers employed the oxacillin agar screen method (27%), automated systems (29%), or a combination of methods (29%) than in 1991 (P<.005). Between 1991 and 1995, the proportion of hospitals reporting MRSA control measures increased from 68% to 95% (P<.01). Practices that were used increasingly included patient placement in private room (from 50% to 93%,P<.01) and hand decontamination with antiseptic (from 43% to 87%,P<.01). The proportion of centers that reported screening MRSA carriers and treating them topically increased two- and threefold, respectively (P<.05). Surveillance data from 1994 to 1995 showed that MRSA represented a mean of 21.3% ofS aureusclinical isolates (range, 1.6% to 62.4%). The median incidence of nosocomial MRSA acquisition was 2.8 per 1,000 admissions, with a wide range (0 to 13.7 per 1,000 admissions) across hospitals of all sizes. The median incidence decreased over the first three semesters of surveillance in hospitals with continuous participation.

Conclusion:MRSA detection and control measures have improved in Belgian hospitals after publication of national guidelines. However, MRSA incidence rates show the persistence of nosocomial transmission, with large variations between centers. The national MRSA surveillance network should indicate whether control efforts eventually will curb the problem.

Antibiotic susceptibility of intra-abdominal infection isolates from Indian hospitals during 2008

A total of 542 clinical isolates of aerobic Gram-negative bacilli from intra-abdominal infections were collected during 2008 from seven hospitals in India participating in the Study for Monitoring Antimicrobial Resistance Trends (SMART). Isolates were from various infection sources, the most common being gall bladder (30.1 %) and peritoneal fluid (31.5 %), and were mostly hospital-associated isolates (70.8 %) as compared to community-acquired (26.9 %). The most frequently isolated pathogens were Escherichia coli (62.7 %), Klebsiella pneumoniae (16.7 %) and Pseudomonas aeruginosa (5.3 %). Extended-spectrum beta-lactamase (ESBL) rates in E. coli and K. pneumoniae were very high, at 67 % and 55 %, respectively. Most isolates exhibited resistance to one or more antibiotics. The most active drugs were generally ertapenem, imipenem and amikacin. However, hospital-acquired isolates in general, as well as ESBL-positive isolates, exhibited lower susceptibilities than community-acquired isolates. Further surveillance monitoring of intra-abdominal isolates from India is recommended.

COMPARISON OF INFECTION RATE USING DIFFERENT METHODS OF ASSESSMENT FOR SURVEILLANCE OF TOTAL HIP REPLACEMENT SURGICAL SITE INFECTIONS

BACKGROUND

The surveillance of surgical site infections (SSI) has been undertaken in many centres worldwide to ascertain the extent of the problem and where possible, to improve the incidence rates, thereby decreasing the undesirable outcomes. The study investigates the processes and outcomes of total hip replacement SSI surveillance carried out in Dunedin Public Hospital in 2004.

METHODS

Two hundred and six patients were enlisted in the study and 189 primary replacements and 22 revision replacements were carried out. Four methods of diagnosis of SSI were applied: (i) clinician diagnosis; (ii) ASEPSIS score; (iii) presence of pus cells; and (iv) assessment by a clinical microbiologist. Infection rates were calculated according to the risk indexes.

RESULTS

The incidence of infections varies considerably among these four methods. The infection rates for risk index 0 were 4.35% (method 1), 2.61% (method 2), 0.87% (methods 3 and 4); and for risk indexes 1 and 2 were 4.17% (method 1), 2.08% (method 2), 1.04% (methods 3 and 4).

CONCLUSION

There is a need for accurate infection data so that the appropriate follow-up responses, including infection control measures for total hip replacement SSI can be carried out. The preponderance of elderly patients in the study who are frequently on 'polypharmacy' regimens adds pressure to the need to obtain true infection rates. This is because when antimicrobials are prescribed to them, drug interactions, adverse effects of the antimicrobials and the selective pressure of antimicrobials causing resistances may occur. More resources and a multidisciplinary approach are required for future studies of similar nature.

Staphylococcus aureus, the major pathogen in orthopaedic and cardiac surgical site infections: a literature review

Due to the increasing number of orthopaedic and cardiac procedures, these units are considered as high-risk areas because of the potentially serious consequences of surgical site infections (SSI), primarily caused by Staphylococcus aureus. The goal of this review was to evaluate the impact of S. aureus on the incidence of SSI in these high risk wards. Studies were identified by a search on the MEDLINE literature using the following mesh terms: S. aureus, cardiac, orthopaedic, surgery, SSI. Beside, data from different surveillance systems were also included. Overall, biological investigation was performed only on a small proportion of identified SSIs. Of those identified, S. aureus represented the most common pathogen accounting for approximately 20% of all SSIs. Of the 59,274 hip prostheses reported from the HELICS surveillance network, S. aureus formed 48.6% of the pathogens (416 bacteria isolated). Similarly, it represented 43.7% of pathogens after coronary artery bypass grafting. Although S. aureus turned out to be the major pathogen, this work identifies the relative lack of knowledge on the overall incidence of S. aureus infections and on the impact of this pathogenic agent when taking into consideration the degree of wound contamination and category of SSI. There is a need for more detailed information on the role of S. aureus in the burden of surgical site infections and consequently how to establish multiple approach prevention programs.

Surgical site infection - a European perspective of incidence and economic burden

This retrospective review of reported surgical site infection (SSI) rates in Europe was undertaken to obtain an estimated scale of the problem and the associated economic burden. Preliminary literature searches revealed incomplete datasets when applying the National Nosocomial Infection Surveillance System criteria. Following an expanded literature search, studies were selected according to the number of parameters reported, from those identified as critical for accurate determination of SSI rates. Forty-eight studies were analysed. None of the reviewed studies recorded all the data necessary to enable a comparative assessment of the SSI rate to be undertaken. The estimated range from selected studies analysed varied widely from 1.5-20% - a consequence of inconsistencies in data collection methods, surveillance criteria and wide variations in the surgical procedures investigated - often unspecified. SSIs contribute greatly to the economic costs of surgical procedures - estimated range: 1.47-19.1 billion Euro dollars. The analysis suggests that the true rate of SSIs, currently unknown, is likely to have been previously under-reported. Consequently, the associated economic burden is also likely to be underestimated. A significant improvement in study design, data collection, analysis and reporting will be necessary to ensure that SSI baseline rates are more accurately assessed to enable the evaluation of future cost-effective measures.

Postdischarge clean wound infections: incidence underestimated and risk factors overemphasized

BACKGROUND

Wound infections are a leading cause of postoperative morbidity and a cost to both the individual and community. The surgeon now has a reduced appreciation of wound-infection rates because of shorter hospital stays and an increasing reliance on the primary care physicians. The incidence of wound infections which occurred following clean surgical procedures, as well as whether they could have been predicted by the known risk factors, were analysed in the present prospective study.

METHODS

A prospective audit of the first 30 postoperative days following clean general surgical wounds was undergone, with inpatient assessment by a research nurse, and subsequent outpatient followup by patient telephone interview.

RESULTS

Of 1964 clean wounds over a 30-month period, 98.5% were traced. The overall clean-wound infection rate was 12.6% (inpatient:4.5%; outpatient: 8.1%). Inpatient infection rates(but not postdischarge wound-infection rates) were significantly correlated (P < 0.05)to the American Society of Anesthesiologists' rating, operation duration, preoperative day stay, and age. Infection rates varied with operation type: vascular (18.3%), breast (16.0%),abdominal (10.3%), hernia (8.0%), head and neck (7.1%).

CONCLUSIONS

The overall wound-infection rate is higher than previously described with two thirds of infections occurring after discharge. While inpatient wound-infection rates fit known risk factors, postdischarge wound-infection rates do not. Certain clean-wound operations have a higher incidence of infection than others. Consideration needs to be given to the identification of risk factors for postdischarge wound infections,and to further trials of prophylactic antibiotics in clean surgery.

Postdischarge nosocomial infections in primary care

OBJECTIVE

To study both surgical and nonsurgical nosocomial infections (NIs) seen by primary-care physicians (general practitioners [GPs]) in France.

DESIGN

Ongoing surveillance of postdischarge NIs by an organized group of GPs, from August 1997 to July 1999. Both the GP who personally examined the case spontaneously presenting with NI and the responsible hospital physician or surgeon were interviewed by telephone.

SETTING

305 general practices from all French regions.

RESULTS

2,199 (29%) of 7,540 patients referred for hospitalization reconsulted the GP within 30 days of discharge. In 21 (1%) of the 2,199 cases, an NI was diagnosed by the GP and confirmed as plausible by the responsible hospital physician. We diagnosed an NI in 8 (1.3%) of the post-surgical patients and in 13 (0.8%) of the non-surgical cases within the cohort. We saw eight urinary tract infections, seven surgical-site infections, three soft-tissue infections, two respiratory tract infections, and one primary bloodstream infection. In 19 patients (90%), clinical signs of NI appeared within 7 days of discharge. Assuming that all 5,431 patients who were missed for follow-up did not experience any NI, an attack rate of 0.3 per 100 admissions may be estimated for the whole group.

CONCLUSION

We diagnosed 1% of NIs following discharge from a hospital in a cohort of 2,199 patients, of which 1.3% were seen post-surgery and 0.8% following nonsurgical admissions. The percentage of postdischarge visits that were for an NI in nonsurgical patients warrants a major effort with feedback to the hospital physician to reduce infection rates.

Surveillance of hospital-acquired infection in England, Germany, and The Netherlands: will international comparison of rates be possible?

Three national surveillance systems for nosocomial infection have been developed independently and implemented successfully in England, Germany, and The Netherlands. All three are based on the American National Nosocomial Infections Surveillance System and have adopted a surveillance strategy that is targeted at specific infections or groups of patients for limited time periods. Case-finding methods, the minimum data set, and analysis of data are similar and could be standardized easily. Resolution of the differences in the definitions of infection, the study population, and follow-up should make possible the international comparison of infection rates. Such comparisons may identify differences in healthcare practices between countries and suggest areas for improvement.

Surgical site infection surveillance

Surgical site infection (SSI) is the third most commonly reported nosocomial infection and accounts for 14-16% of all nosocomial infections among hospital inpatients. A successful SSI surveillance programme includes standardized definitions of infection, effective surveillance methods and stratification of the SSI rates according to risk factors associated with the development of SSI. Surveillance with feedback of information to surgeons and other relevant staff has been shown to be an important element in the overall strategy to reduce the numbers of SSIs. This paper examines the essential components of a SSI surveillance system including surveillance methods, data collection and handling, analysis and presentation of results to clinical staff.

Standardising surveillance of nosocomial infections: the HISS program. Hospital Infection Standardised Surveillance

Standardised surveillance of nosocomial infections in Australia had not been addressed until June 1998 when the New South Wales Health Department funded the development and implementation of the first standardised surveillance system for hospital infection: the Hospital Infection Standardised Surveillance program (HISS). The introduction of a standardised surveillance system needs to balance the requirements of a Health Department and the needs of hospitals. The Health Department requires data to develop aggregated rates for the setting of thresholds for all nosocomial infections while hospitals require rates to reflect the quality of clinical care and provide data for evidence-based infection control practices. The Hospital Infection Epidemiology and Surveillance (HIES) Unit has attempted to balance these requirements using a 'sentinel surveillance' approach with standardised definitions and methodology. The HISS program utilizes eICAT software modified for its standardised requirements of data collection. To date, 10 hospitals surveyed sentinel multiple resistant organisms (MRO), eight also elected sentinel surgical procedures (SSP) and intravascular device-related bacteraemia (IVDRB) modules, and two the seasonal respiratory syncytial (RSV) and rota-virus modules in paediatric patients. The surgical site infection rates in three commonly monitored SSP were 1.8% (95% confidence interval (CI) 0.7-3.9%) for coronary artery bypass (CABG), 3.3% (95% CI 1.4-6.8%) lower segment Caesarean section (LSCS) and 7.7% (95% CI 3.4-14.6%) colorectal surgery. The rate of IVDRB was 4.7 per 1000 central venous catheter days (95% CI 2.2-8.6) and 1.1 per 1000 peripheral line-days (95% CI 0.1-3.9). Methicillin resistant Staphylococcus aureus (MRSA) accounted for 99% of all new infections diagnosed with an endemic MRO.

Emergence of Enterobacter aerogenes as a major antibiotic-resistant nosocomial pathogen in Belgian hospitals

OBJECTIVE

To study the epidemiology of Enterobacter aerogenes infections in Belgian hospitals and determine whether recent trends show an increase in incidence of E. aerogenes infections and antimicrobial resistance.

METHODS

Data from the bloodstream infection component of the National Surveillance of Hospital Infections (October 1992 to September 1996 data in 45 hospitals) and from a retrospective study on E. aerogenes clinical isolates (1994 and 1995 data in 41 hospitals) were analyzed.

RESULTS

E. aerogenes was recovered from clinical specimens with a mean incidence of 4.6 isolates per 10 000 patient-days and caused 0.20 bloodstream infections per 10 000 patient-days during the surveyed periods, respectively. Both rates increased significantly throughout the years. The proportion of E aerogenes within the Enterobacter genus was 35.4% in clinical isolates and 41.2% in bloodstream infections. Both proportions significantly increased over time. Incidence was not statistically different by hospital size but showed major differences between geographic regions. Resistance rates to third-generation cephalosporins and fluoroquinolones increased, and imipenem resistance emerged in several hospitals.

CONCLUSIONS

This report provides evidence of an increase in E. aerogenes infections in Belgian hospitals and documents an increase in antimicrobial resistance of E. aerogenes strains. These figures provide a baseline for further surveillance data.

Guideline for prevention of surgical site infection, 1999. Hospital Infection Control Practices Advisory Committee

The “Guideline for Prevention of Surgical Site Infection, 1999” presents the Centers for Disease Control and Prevention (CDC)'s recommendations for the prevention of surgical site infections (SSIs), formerly called surgical wound infections. This two-part guideline updates and replaces previous guidelines.

Part I, “Surgical Site Infection: An Overview,” describes the epidemiology, definitions, microbiology, pathogenesis, and surveillance of SSIs. Included is a detailed discussion of the pre-, intra-, and postoperative issues relevant to SSI genesis.

The validity of surgical wound infection as a clinical indicator in Australia

BACKGROUND

Evidence-based medicine and measurement of outcome have become the foremost strategy of departments of health and quality care in Australia in the 1990s. The Australian Council of Healthcare Standards, (ACHS), formed in 1974, has introduced a Clinical Indicators Programme which monitors a number of clinical outcomes, including rates of specific nosocomial infections. It is the only formal system in Australia which attempts to monitor nosocomial infection in hospitals, and the ACHS acknowledges that the data provided to them are collected using a variety of sources and definitions.

METHODS

The present study discusses the validity of the present definitions of nosocomial surgical wound infection used for accreditation, how validity may be improved and the attempts by some international systems to improve their own data.

RESULTS

The ACHS definitions of nosocomial surgical wound infection lack validity, and the rates provided lack generalizability. Several international surveillance systems have resources in place to provide members with standardized training for practitioners, and support for methodology, data analysis and reporting, which assists in improving the quality of the data collected.

CONCLUSION

It is our belief that the validity of surgical wound infections will be improved by adoption of National Nosocomial Infection Surveillance (NNIS) definitions, stratification of surgical wound infections by anatomical site of infection for sentinel procedures. The ACHS system must adopt the proposed changes if the rates are to be used as a local and national indicator.