Nine-year downward trends in surgical site infection rate in southeast France (1995–2003)

The incidence and cost implications of surgical site infection following lymph node surgery for skin malignancy

BACKGROUND

Lymph node surgery is commonly performed in the staging and treatment of metastatic skin cancer. Previous studies have demonstrated sentinel lymph node biopsy (SLNB) and, particularly, lymph node dissection (LND) to be plagued by high rates of wound complications, including surgical site infection (SSI) and seroma formation. This study evaluated the incidence of wound complications following lymph node surgery and provided the first published cost estimate of SSI associated with lymph node surgery in the UK.

PATIENTS AND METHODS

A retrospective cohort study of 169 patients with a histological diagnosis of primary skin malignancy who underwent SLNB or LND of the axilla and/or inguinal region at a single tertiary centre over a 2 year period was conducted. Demographic, patient risk factor, and operation characteristics data were collected and effect on SSI and seroma formation was analysed. Cost-per-infection was estimated using National Health Service (NHS) reference and antibiotic costs.

RESULTS

A total of 146 patients underwent SLNB with a SSI rate of 4.1% and a seroma incidence of 12.3%. Twenty-three patients underwent LND with a SSI rate of 39.1% and a seroma incidence of 39.1%. Seroma formation was strongly associated with the development of SSI in both the SLNB (odds ratio (OR) = 18.0, p < 0.001) and LND (OR = 21.0, p = 0.007) group. The median additional cost of care events and treatment of SSI in the SLNB and LND groups was £199.46 and £5187.04, respectively.

CONCLUSION

SSI remains a troublesome and costly event following SLNB and LND. Further research into perioperative care protocols and methods of reducing lymph node surgery morbidity is required and could result in significant cost savings to the NHS.

Use of surveillance data to calculate the sample size and the statistical power of randomized clinical trials testing Staphylococcus aureus vaccine efficacy in orthopedic surgery

BACKGROUND

Patients undergoing primary total hip arthroplasty (THA) would be a worthy population for anti-staphylococcal vaccines. The objective is to assess sample size for significant vaccine efficacy (VE) in a randomized clinical trial (RCT).

METHODS

Data from a surveillance network of surgical site infection in France between 2008 and 2011 were used. The outcome was S. aureus SSI (SASSI) within 30 days after surgery. Statistical power was estimated by simulations repeated for theoretical VE ranging from 20% to 100% and for sample sizes from 250 to 8000 individuals per arm.

RESULTS

18,688 patients undergoing THA were included; 66 (0.35%) SASSI occurred. For a 1% SASSI rate, the sample size would be at least 1316 patients per arm to detect significant VE of 80% with 80% power.

CONCLUSION

Simulations with real-life data from surveillance of hospital acquired infections allow estimation of power for RCT and sample size to reach the required power.

Impact of nosocomial infections surveillance on nosocomial infection rates: A systematic review

BACKGROUND

According to previously studies, nosocomial infections (NIs) surveillance could effectively reduce infection rates. As NIs surveillance systems have been implemented in some hospitals for several years, their impact on NIs need to be explored. Therefore, the purpose of this review is to evaluate the tendency of NI rates during the surveillance period and the impact of surveillance on NI rates.

METHODS

A systematic literature search of the PubMed database to identify papers that evaluated effect of surveillance on NIs, all kinds of NIs occurred during hospitalization or discharged were included. Exclude articles investigated the surveillance combined with other infection control measures.

RESULTS

Twenty-five articles were included. NI rates had different levels of reduction during surveillance period, the reduction were not limited by state, department, surveillance system, and NI type. Continuous surveillance had a positive impact on NI, OR/RR were ranged from 0.43 to 0.95.

CONCLUSION

Participation in NI surveillance is associated with reducing infection rates, though RCTs need to further prove the effective role of surveillance. Hospitals may consider to perform NIs surveillance systems according to its own conditions.

Is hospital information system relevant to detect surgical site infection? Findings from a prospective surveillance study in posterior instrumented spinal surgery

OBJECT

Spinal instrumentation has a high rate of surgical site infection (SSI), but results greatly vary depending on surveillance methodology, surgical procedures, or quality of follow-up. Our aim was to study true incidence of SSI in spinal surgery by significant data collection, and to compare it with the results obtained through the hospital information system.

METHODS

This work is a single center prospective cohort study that included all patients consecutively operated on for spinal instrumentation by posterior approach over a six-month period regardless the etiology. For all patients, a "high definition" prospective method of surveillance was performed by the infection control (IC) department during at least 12 months after surgery. Results were then compared with findings from automatic surveillance though the hospital information system (HIS).

RESULTS

One hundred and fifty-four patients were included. We found no hardly difference between "high definition" and automatic surveillance through the HIS, even if HIS tended to under-estimate the infection rate: rate of surgical site infection was 2.60% and gross SSI incidence rate via the hospital information system was 1.95%. Smoking and alcohol consumption were significantly related to a SSI.

CONCLUSION

Our SSI rates to reflect the true incidence of infectious complications in posterior instrumented adult spinal surgery in our hospital and these results were consistent with the lower levels of published infection rate. In-house surveillance by surgeons only is insufficiently sensitive. Further studies with more patients and a longer inclusion time are needed to conclude if SSI case detection through the HIS could be a relevant and effective alternative method.

Use of surveillance data to identify target populations for Staphylococcus aureus vaccines and prevent surgical site infections: a pilot study

The development of anti-staphylococcal vaccines is nowadays a priority to prevent surgical site infections (SSI). The objective of the present study was to identify a potential target population by assessing surveillance data on surgery patients for possible anti-staphylococcal vaccine administration. Individuals at high risk of SSI by Staphylococcus aureus (SA) were targeted by the French SSI Surveillance Network in south-eastern France between 2008 and 2011. Among 238,470 patients, those undergoing primary total hip replacement appeared to be an interesting and healthy enough population for anti-staphylococcal vaccine testing. These male patients, subjected to multiple procedures and with American Society of Anesthesiologists score>2, had a probability of SA SSI about 21 times higher than females with no severe systemic disease and no multiple procedures. Our study indicates that surveillance data on SSI might be an interesting epidemiological source for planning vaccine trials to prevent nosocomial infections.

Trends in the Incidence of Surgical Site Infection in The Netherlands

Objective.

To evaluate the time trend in the surgical site infection (SSI) rate in relation to the duration of surveillance in The Netherlands.

Setting.

Forty-two hospitals that participated in the the Dutch national nosocomial surveillance network, which is known as PREZIES (Preventie van Ziekenhuisinfecties door Surveillance), and that registered at least 1 of the following 5 frequently performed surgical procedures for at least 3 years during the period from 1996 through 2006: mastectomy, colectomy, replacement of the head of the femur, total hip arthroplasty, or knee arthroplasty.

Methods.

Analyses were performed for each surgical procedure. The surveillance time to operation was stratified in consecutive 1-year periods, with the first year as reference. Multivariate logistic regression analysis was performed using a random coefficient model to adjust for random variation among hospitals. All models were adjusted for method of postdischarge surveillance.

Results.

The number of procedures varied from 3,031 for colectomy to 31,407 for total hip arthroplasty, and the SSI rate varied from 1.6% for knee arthroplasty to 12.2% for colectomy. For total hip arthroplasty, the SSI rate decreased significantly by 6% per year of surveillance (odds ratio [OR], 0.94 [95% confidence interval {CI}, 0.90–0.98]), indicating a 60% decrease after 10 years. Nonsignificant but substantial decreasing trends in the rate of SSI were found for replacement of the head of the femur (OR, 0.94 [95% CI, 0.88–1.00]) and for colectomy (OR, 0.92 [95% CI, 0.83–1.02]).

Conclusions.

Even though most decreasing trends in the SSI rate were not statistically significant, they were encouraging. To use limited resources as efficiently as possible, we would suggest switching the surveillance to another surgical procedure when the SSI rate for that particular procedure has decreased below the target rate.

Evaluating the clinical and economic burden of healthcare-associated infections during hospitalization for surgery in France

Over 4 million patients suffer nosocomial infections annually in the European Union. This study aimed to estimate the healthcare burden associated with healthcare-associated infections (HAIs) following surgery in France, and explore the potential impact of infection control strategies and interventions on the clinical and economic burden of disease. Data on the frequency of HAIs were gathered from the 2010 Programme de Médicalisation des Systèmes d'Information (PMSI), and cost data were taken from the 2009 Echelle Nationale de Coûts à Méthodologie Commune (ENCC). It was estimated that 3% of surgical procedures performed in 2010 in France resulted in infection, resulting in an annual cost of €57 892 715. Patients experiencing a HAI had a significantly increased mortality risk (4·15-fold) and an increased length of hospital stay (threefold). Scenario analysis in which HAI incidence following surgery was reduced by 8% (based on a study of the effectiveness of triclosan-coated sutures), suggested that, annually, 20 205 hospital days and €4 588 519 could be saved. Analyses of 20% and 30% reductions in incidence (based on an estimate of the number of preventable nosocomial infections) suggested that annual savings of €11 548 057 and €17 334 696, respectively, could be made. New infection control interventions which reduce HAI incidence during hospitalization for surgery have the potential to provide valuable cost savings to healthcare providers.

Impact of surveillance of hospital-acquired infections on the incidence of ventilator-associated pneumonia in intensive care units: a quasi-experimental study

INTRODUCTION

The preventive impact of hospital-acquired infection (HAI) surveillance is difficult to assess. Our objective was to investigate the effect of HAI surveillance disruption on ventilator-associated pneumonia (VAP) incidence.

METHODS

A quasi-experimental study with an intervention group and a control group was conducted between 1 January 2004 and 31 December 2010 in two intensive care units (ICUs) of a university hospital that participated in a national HAI surveillance network. Surveillance was interrupted during the year 2007 in unit A (intervention group) and was continuous in unit B (control group). Period 1 (pre-test period) comprised patients hospitalized during 2004 to 2006, and period 2 (post-test period) involved patients hospitalized during 2008 to 2010. Patients hospitalized ≥ 48 hours and intubated during their stay were included. Multivariate Poisson regression was fitted to ascertain the influence of surveillance disruption.

RESULTS

A total of 2,771 patients, accounting for 19,848 intubation-days at risk, were studied; 307 had VAP. The VAP attack rate increased in unit A from 7.8% during period 1 to 17.1% during period 2 (P <0.001); in unit B, it was 7.2% and 11.2% for the two periods respectively (P = 0.17). Adjusted VAP incidence rose in unit A after surveillance disruption (incidence rate ratio = 2.17, 95% confidence interval 1.05 to 4.47, P = 0.036), independently of VAP trend; no change was observed in unit B. All-cause mortality and length of stay increased (P = 0.028 and P = 0.038, respectively) in unit A between periods 1 and 2. In unit B, no change in mortality was observed (P = 0.22), while length of stay decreased between periods 1 and 2 (P = 0.002).

CONCLUSIONS

VAP incidence, length of stay and all-cause mortality rose after HAI surveillance disruption in ICU, which suggests a specific effect of HAI surveillance on VAP prevention and reinforces the role of data feedback and counselling as a mechanism to facilitate performance improvement.

Reproducibility of the surveillance effect to decrease nosocomial infection rates

OBJECTIVE

To investigate whether the reduction effect due to participation in a nosocomial infection surveillance system for laboratory-confirmed central venous catheter (CVC)-associated primary bloodstream infection (BSI), ventilator-associated pneumonia (VAP), and surgical site infection (SSI) is reproducible for different time periods, independent of confounding factors that might occur during a specific time period.

METHODS

Data from the German national nosocomial infection surveillance system from the period January 1997 through June 2008 were used. CVC-associated BSI data and SSI data were analyzed for 3 starting periods, and VAP data were analyzed for 2 starting periods. Monthly infection rates were calculated for the following 36 months, and relative risks comparing the first and third surveillance years of each period were calculated.

RESULTS

A total of 2,399 CVC-associated BSI cases from 267 intensive care units, 3,637 VAP cases from 150 intensive care units, and 829 SSIs following 3 different procedures from 113 departments were analyzed. A significant reduction in VAP was shown for both starting periods investigated (overall relative risk [RR], 0.80 [95% CI, 0.74-0.86]). A significant reduction in CVC-associated BSI was demonstrated for 2 of 3 starting periods (overall RR, 0.83 [95% CI, 0.75-0.91]). A significant reduction in SSI was found for 2 starting periods for knee prosthesis insertion (overall RR, 0.56 [95% CI, 0.38-0.82]), for all of the 3 starting periods for cesarean delivery (overall RR, 0.75 [95% CI, 0.61-0.93]), and for none of the 3 starting periods for endoscopically performed cholecystectomy (overall RR, 0.89 [95% CI, 0.62-1.27]).

CONCLUSIONS

The surveillance effect, manifest as a significant reduction of nosocomial infection rates between the first and third years of participation in a surveillance system, was observed independently from the calendar year in which the surveillance activities started.

Improving surveillance system and surgical site infection rates through a network: A pilot study from Thailand

Background:

Surveillance of surgical site infections (SSI) provides data upon which interventions to improve patient safety can be based. In Thailand, however, SSI surveillance has not yet been standardized.

Objectives:

To develop a standardized SSI surveillance system and to monitor SSI rates after introduction of such a system.

Methods:

We conducted a prospective study among 17,752 patients who underwent surgery in ten hospitals in Thailand from April 2004 to May 2005. The SSI rates were computed and benchmarked with the US rates, reported in terms of standardized infection ratio (SIR). We estimated the incidence rate ratio of surgical site infections by comparing the incidence in the last study period with the incidence in the first study period.

Results:

The study included 17,869 operations and identified 248 SSIs, yielding an SSI rate of 1.4 infections/100 operations and a corresponding SIR of 0.6 (95% confidence interval [CI] = 0.5–0.7). During the study period the overall SSI rate decreased from 1.8 infections/100 operations to 1.2 infections/100 operations, yielding an incidence rate ratio of 0.65 (95% CI = 0.47–0.89).

Conclusion:

Our study highlighted that a standardized SSI surveillance in a developing country can be initiated through a network and may be followed by a decrease in SSI rates.

Reducing surgical site infection incidence through a network: results from the French ISO-RAISIN surveillance system

Surgical-site infections (SSIs) are a key target for nosocomial infection control programmes. We evaluated the impact of an eight-year national SSI surveillance system named ISO-RAISIN (infection du site opératoire - Réseau Alerte Investigation Surveillance des Infections). Consecutive patients undergoing surgery were enrolled during a three-month period each year and surveyed for 30 days following surgery. A standardised form was completed for each patient including SSI diagnosis according to standard criteria, and several risk factors such as wound class, American Society of Anesthesiologists (ASA) score, operation duration, elective/emergency surgery, and type of surgery. From 1999 to 2006, 14,845 SSIs were identified in 964,128 patients (overall crude incidence: 1.54%) operated on in 838 participating hospitals. The crude overall SSI incidence decreased from 2.04% to 1.26% (P<0.001; relative reduction: -38%) and the National Nosocomial Infections Surveillance system (NNIS)-0 adjusted SSI incidence from 1.10% to 0.74% (P<0.001; relative reduction: -33%). The most significant SSI incidence reduction was observed for hernia repair and caesarean section, and to a lesser extent, cholecystectomy, hip prosthesis arthroplasty, and mastectomy. Active surveillance striving for a benchmark throughout a network is an effective strategy to reduce SSI incidence.