To evaluate the performance of a comorbidity-based risk-adjustment model for surgical-site infection (SSI) reporting and benchmarking using a panel of variables extracted from the hospital discharge database (HDD), including comorbidities, compared to other models that use variables from different data sources.

The French national surveillance program for SSI (SPICMI) has collected data from voluntary hospitals in the first 6 months of 2020 and 2021, for 16 selected surgery procedures, using a semiautomated algorithm for detection. Four risk-adjustment models were selected with logistic regression analysis, combining the different patterns of variables: National Nosocomial Infections Surveillance System (NNIS) risk-index components, individual operative data, and 6 individual comorbidities according to International Classification of Disease, Tenth Revision (ICD-10) diagnosis: obesity, diabetes, malnutrition, hypertension, cancer, or immunosuppression. Areas under the curve (AUCs) were calculated and compared.

Overall, 294 SSI were detected among 11,975 procedures included. All 6 comorbidities were related to SSI in the univariate analysis. The AUC of the selected model including comorbidities (0.675; 95% confidence interval [CI], 0.642–0.707), was significantly higher than the AUC of the model without comorbidities (0.641; 95% CI, 0.609–0.672; P = .016) or the AUC using the NNIS-index components (0.598; 95% CI, 0.564–0.630; P < .001). The HDD-based model AUC (0.659; 95% CI, 0.625–0.692) did not differ significantly from the selected model without comorbidities (P = .23).

Including HDD-based comorbidities as patient case-mix variables instead of NNIS risk index factors could be an effective approach for risk-adjustment of automated SSI surveillance more widely accessible to hospitals.

The French National Authority for Health (HAS), with a multidisciplinary working group, developed an indicator ‘ISO-ORTHO’ to assess surgical site infections (SSIs) after total hip arthroplasty or total knee arthroplasty (THA/TKA) based on the hospital discharge database. We present the ISO-ORTHO indicator designed for SSI automated detection and its relevance for quality improvement and hospital benchmarks.

The algorithm is based on a combination of International Statistical Classification of Diseases, Tenth Revision (ICD-10) and procedure codes of the hospital stay. The target population was selected among adult patients who had a THA or TKA between January 1, 2017, and September 30, 2017. Patients at very high risk of SSI and/or with SSI not related to hospital care were excluded. We searched databases for SSIs up to 3 months after THA/TKA. The standardized infection ratio (SIR) of observed versus expected SSIs was calculated (logistic regression) and displayed as funnel plot with 2 and 3 standard deviations (SD) after adjustment for 13 factors known to increase SSI risk.

In total, 790 hospitals and 139,926 THA/TKA stays were assessed; 1,253 SSI were detected in the 473 included hospitals (incidence, 0.9%: 1.0% for THA, 0.80% for TKA). The SSI rate was significantly higher in males (1.2%), in patients with previous osteo-articular infection (4.4%), and those with cancer (2.3%), obesity, or diabetes. Most hospitals (89.9%) were within 2 SD; however, 12 hospitals were classified as outliers at more than +3 SD (1.6% of facilities), and 59 hospitals (7.9%) were outliers between +2 SD and +3 SD.

ISO-ORTHO is a relevant indicator for automated surveillance; it can provide hospitals a metric for SSI assessment that may contribute to improving patient outcomes.

Hip or knee arthroplasty infection (HKAI) leads to heavy medical consequences even if rare.

To assess the routine use of a hospital discharge detection algorithm of prosthetic joint infection as a novel additional tool for surveillance.

A historic 5-year cohort study was built using a hospital database of people undergoing a first hip or knee arthroplasty in 1 French region (2.5 million inhabitants, 39 private and public hospitals): 32,678 patients with arthroplasty code plus corresponding prosthetic material code were tagged. HKAI occurrence was then tracked in the follow-up on the basis of a previously validated algorithm using International Statistical Classification of Disease, Tenth Revision, codes as well as the surgical procedures coded. HKAI density incidence was estimated during the follow-up (up to 4 years after surgery); risk factors were analyzed using Cox regression.

A total of 604 HKAI patients were identified: 1-year HKAI incidence was1.31%, and density incidence was 2.2/100 person-years in hip and 2.5/100 person-years in knee. HKAI occurred within the first 30 days after surgery for 30% but more than 1 year after replacement for 29%. Patients aged 75 years or older, male, or having liver diseases, alcohol abuse, or ulcer sore had higher risk of infection. The inpatient case fatality in HKAI patients was 11.4%.

The hospital database method used to measure occurrence and risk factors of prosthetic joint infection helped to survey HKAI and could optimize healthcare delivery.

Infect Control Hosp Epidemiol 2015;36(10):1198–1207

Surgical site infection (SSI) surveillance represents a key method of nosocomial infection control programs worldwide. However, most SSI surveillance systems are considered to be poorly cost effective regarding human and economic resources required for data collection and patient follow up. This study aims to assess the efficacy of using hospital discharge databases (HDDs) as a routine surveillance system for detecting hip or knee arthroplasty–related infections (HKAIs).

A case-control study was conducted among patients hospitalized in the Centre region of France between 2008 and 2010. HKAI cases were extracted from the HDD with various algorithms based on the International Classification of Diseases, Tenth Revision, and procedure codes. The control subjects were patients with hip or knee arthroplasty (HKA) without infection selected at random from the HDD during the study period. The gold standard was medical chart review. Sensitivity (Se), specificity (Spe), positive predictive value (PPV), and negative predictive value (NPV) were calculated to evaluate the efficacy of the surveillance system.

Among 18,265 hospital stays for HKA, corresponding to 17,388 patients, medical reports were checked for 1,010 hospital stays (989 patients). We identified 530 cases in total (incidence rate, 1% [95% confidence interval (CI), 0.4%–1.6%), and 333 cases were detected by routine surveillance. As compared with 480 controls, Se was 98%, Spe was 71%, PPV was 63%, and NPV was 99%. Using a more specific case definition, based on a sample of 681 hospital stays, Se was 97%, Spe was 95%, PPV was 87%, and NPV was 98%.

This study demonstrates the potential of HDD as a tool for routine SSI surveillance after low-risk surgery, under conditions of having an appropriate algorithm for selecting infections.

Infect Control Hosp Epidemiol 2014;35(6):646–651

To describe the French program for the prevention of healthcare-associated infections and antibiotic resistance and provide results for some of the indicators available to evaluate the program. In addition to structures and process indicators, the 2 outcome indicators selected were the rate of surgical site infection and the proportion of methicillin-resistant Staphylococcus aureus (MRSA) isolates among the S. aureus isolates recovered.

Descriptive study of the evolution of the national structures for control of healthcare-associated infections since 1992. Through national surveillance networks, process indicators were available from 1993 to 2006, surgical site infection rates were available from 1999 to 2005, and prevalence rates for MRSA infection were available from 2001 to 2007.

A comprehensive national program has gradually been set up in France during the period from 1993 to 2004, which included strengthening of organized infection control activities at the local, regional, and national levels and developing large networks for surveillance of specific infections and antibiotic resistance. These achievements were complemented by instituting mandatory notification for unusual nosocomial events, especially outbreaks. The second phase of the program involved the implementation of 5 national quality indicators with public reporting. Surgical site infection rates decreased by 25% over a 6-year period. In France, the median proportion of MRSA among S. aureus isolates recovered from patients with bacteremia decreased from 33.4% to 25.7% during the period from 2001 to 2007, whereas this proportion increased in many other European countries.

Very few national programs have been evaluated since the Study on the Efficacy of Nosocomial Infection Control. Although continuing efforts are required, the French program appears to have been effective at reducing infection rates.

To evaluate whether the standardized incidence ratio (SIR) is a more reliable tool for comparing rates and temporal trends of surgical site infection (SSI) in surgery wards than the incidence rate among patients with an National Nosocomial Infections Surveillance system (NNIS) risk index category of 0.

Observational, prospective cohort study in a sequential SSI surveillance system.

Volunteer surgery wards in a surveillance network in northern France that annually conducted SSI surveillance for 3 months from 1998 to 2000.

The incidence rate was the number of SSIs divided by the number of patients included, stratified by the NNIS risk index category. SIR was the observed number of SSIs divided by the expected number computed using a multiple regression model.

Overall, 26,904 patients in 67 surgery wards were enrolled. Between 1998 and 2000, the SSI incidence rate among patients with NNIS risk index category 0 decreased from 2.1% to 1.4%, which was a 33% reduction (P = .002). The SIR decreased from 1.2 (95% confidence interval [CI], 1.1-1.3) to 0.8 (95% CI, 0.7-0.9), which was a 20% decrease per year and an overall 33% reduction. The number of SSIs was significantly higher than expected in 17 of 201 surveillance periods over the 3 years. The classification of the wards according to the 2 indicators over the 3 years showed that wards with a high SIR did not consistently have the highest SSI incidence rate among patients with NNIS risk index category 0, partly because the type of surgical procedure and the duration of follow-up are not taken into account in the NNIS risk index.

SIR should be considered a reliable indicator to estimate the reduction in SSI incidence that results from implementation of infection control policies and for comparison of SSI rates between wards.

To identify the routes of transmission during an outbreak of infection with hepatitis C virus (HCV) genotype 2a/2c in a hemodialysis unit.

A matched case-control study was conducted to identify risk factors for HCV seroconversion. Direct observation and staff interviews were conducted to assess infection control practices. Molecular methods were used in a comparison of HCV infecting isolates from the case-patients and from patients infected with the 2a/2c genotype before admission to the unit.

A hemodialysis unit treating an average of 90 patients.

A case-patient was defined as a patient receiving hemodialysis with a seroconversion for HCV genotype 2a/2c between January 1994 and July 1997 who had received dialysis in the unit during the 3 months before the onset of disease. For each case-patient, 3 control-patients were randomly selected among all susceptible patients treated in the unit during the presumed contamination period of the case-patient.

HCV seroconversion was associated with the number of hemodialysis sessions undergone on a machine shared with (odds ratio [OR] per additional session, 1.3; 95% confidence interval [CI95], 0.9 to 1.8) or in the same room as (OR per additional session, 1.1; CI95, 1.0 to 1.2) a patient who was anti-HCV (genotype 2a/2c) positive. We observed several breaches in infection control procedures. Wetting of transducer protectors in the external pressure tubing sets with patient blood reflux was observed, leading to a potential contamination by blood of the pressure-sensing port of the machine, which is not accessible to routine disinfection. The molecular analysis of HCV infecting isolates identified among the case-patients revealed two groups of identical isolates similar to those of two patients infected before admission to the unit.

The results suggest patient-to-patient transmission of HCV by breaches in infection control practices and possible contamination of the machine. No additional cases have occurred since the reinforcement of infection control procedures and the use of a second transducer protector.

To compute a risk index for nosocomial infection (NI) surveillance in geriatric long-term-care facilities (LTCFs) and rehabilitation facilities.

Analysis of data collected during the French national prevalence survey on NIs conducted in 1996. Risk indices were constructed based on the patient case-mix defined according to risk factors for NIs identified in the elderly.

248 geriatric units in 77 hospitals located in northern France.

All hospital inpatients on the day of the survey were included.

Data from 11,254 patients were recorded. The overall rate of infected patients was 9.9%. Urinary tract, respiratory tract, and skin were the most common infection sites in both rehabilitation facilities and LTCFs. Eleven risk indices, categorizing patients in 3 to 7 levels of increasing NI risk, ranging from 2.7% to 36.2%, were obtained. Indices offered risk adjustment according to NI rate stratification and clinical relevance of risk factors such as indwelling devices, open bedsores, swallowing disorders, sphincter incontinence, lack of mobility, immunodeficiency, or rehabilitation activity.

The optimal index should be tailored to the strategy selected for NI surveillance in geriatric facilities in view of available financial and human resources.

To evaluate and compare the risk of long-term central venous catheter (CVC) infection in human immunodeficiency virus (HIV)-infected and cancer patients.

Prospective multicenter cohort study based on active surveillance of long-term CVC manipulations and patient outcome over a 6-month period.

Services of infectious diseases and oncology of 12 university hospitals in Paris, France.

In 1995, all HIV and cancer patients with solid malignancy were included at the time of long-term CVC implantation.

Overall, 31.6% of long-term CVC infections were identified in 32% of 201 HIV and 5% of 255 cancer patients. Most were associated with bacteremia, most commonly coagulase-negative staphylococci. The long-term CVC time-related infection risk was greater in HIV than in cancer patients (3.78 vs 0.39 infections per 1,000 long-term CVC days; P<.001). The independent risk factors of long-term CVC infection were as follows: in HIV patients, frequency of long-term CVC handling and neutropenia; in cancer patients, poor Karnofsky performance status; in both HIV and cancer patients, recent history of bacterial infection. The risk of long-term CVC infection was similar for tunneled catheters and venous access ports in each population.

Prevention of long-term CVC infection should focus first on better sterile precautions while handling long-term CVC, especially in HIV patients who have frequent and daily use of the long-term CVC.