Surgical site infections in patients undergoing major operations in a university hospital: using standardized infection ratio as a benchmarking tool

Evaluating antibiotic prophylaxis adherence: Implications for surgical site infections and wound care management

AIM

This study aimed to evaluate adherence to an antibiotic prophylaxis protocol and its impact on incidence of surgical site infection (SSI).

MATERIALS AND METHOD

A prospective observational cohort study was conducted at a teaching hospital in São Paulo, Brazil, from September to November 2015. The population were adults who underwent surgery with surgical antibiotic prophylaxis. The main outcomes measured were incidence of SSI at 30-days postoperatively, protocol adherence and surgical wound complications. STROBE guidelines were followed.

RESULTS

Among the 527 participants recruited, a 30-day follow-up was completed by 78.7 % (n = 415). Within this cohort, 57.6 % were females aged over 60 years (36.4 %). The incidence of SSI stood at 9.4 % (n = 39), with dehiscence being the most prevalent complication at 64.1 % (n = 25), followed by increased exudate at 51.3 % (n = 20). Notably, full adherence to the antibiotic prophylaxis protocol was low at 1.7 % (n = 7). The study observed a 60 % increased risk of SSI for every protocol mistake made. Alarmingly, 17.8 % (n = 74) of participants received antibiotic treatment exceeding the stipulated protocol duration. The overall mortality rate stood at 13.5 % (n = 56), with 1 % (n = 4) of these deaths attributed to SSI.

CONCLUSION

There is a pressing global necessity to enhance antibiotic management, as underscored by this study's revelation of low adherence to the antibiotic prophylaxis protocol. This lack of adherence correlated with a notable incidence of SSI and subsequent wound complications. Nearly 20 % of participants received prolonged antibiotic treatment. Adhering strictly to the protocol could substantially impact SSI-related outcomes and enhance global antibiotic management.

Worldwide incidence of surgical site infections in general surgical patients: A systematic review and meta-analysis of 488,594 patients

BACKGROUND

Establishing worldwide incidence of general surgical site infections (SSI) is imperative to understand the extent of the condition to assist decision-makers to improve the planning and delivery of surgical care. This systematic review and meta-analysis aimed to estimate the worldwide incidence of SSI and identify associated factors in adult general surgical patients.

MATERIALS AND METHODS

A systematic review was undertaken using MEDLINE (Ovid), CINAHL (EBSCO), EMBASE (Elsevier) and the Cochrane Library to identify cross-sectional, cohort and observational studies reporting SSI incidence or prevalence. Studies of less than 50 participants were excluded. Data extraction and quality appraisal were undertaken independently by two review authors. The primary outcome was cumulative incidence of SSI occurring up to 30 days postoperative. The secondary outcome was the severity/depth of SSI. The I² statistic was used to explore heterogeneity. Random effects models were used in the presence of substantial heterogeneity. Subgroup, meta-regression sensitivity analyses were used to explore the sources of heterogeneity. Publication bias was assessed using Hunter's plots and Egger's regression test.

RESULTS

Of 2091 publications retrieved, 62 studies were included. Of these, 57 were included in the meta-analysis across six anatomical locations with 488,594 patients. The pooled 30-day cumulative incidence of SSI was 11% (95% CI 10%-13%). No prevalence data were identified. SSI rates varied across anatomical location, surgical approach, and priority (i.e., planned, emergency). Multivariable meta-regression showed SSI is significantly associated with duration of surgery (estimate 1.01, 95% CI 1.00-1.02, P = .014).

CONCLUSIONS

and Relevance: 11 out of 100 general surgical patients are likely to develop an infection 30 days after surgery. Given the imperative to reduce the burden of harm caused by SSI, high-quality studies are warranted to better understand the patient and related risk factors associated with SSI.

The effects of photobiomodulation therapy on Staphylococcus aureus infected surgical wounds in diabetic rats. A microbiological, histopathological, and biomechanical study

PURPOSE

To evaluate the effects of photobiomodulation therapy (PBMT) at 685 nm on diabetic wound healing in rats suffering from bacterial infection induced by Staphylococcus aureus (S. aureus).

METHODS

Thirty streptozotocin-induced diabetic rats were allocated into two groups: control and PBMT. A 4-cm full-thickness linear-incision was made on the dorsal midline and was contaminated with S. aureus. The wounds in the PBMT group were irradiated daily for 5 consecutive days, starting 3 days after the induction and always in the mornings.

RESULTS

The result revealed that PBMT resulted in a significant decrease in S. aureus CFU in the PBMT group in comparison to the control group (P<0.05). The length of wounds, in the 2nd and 3rd weeks, in the PBMT group were significantly shorter compared to the control group (P<0.05). PBMT caused a significant increase in the histological parameters in comparison to the control group (P<0.05). Moreover, PBMT significantly increased the breaking strength of the surgical scars produced in the skin of the PBMT group when compared to the control group (P<0.05).

CONCLUSION

Photobiomodulation therapy may be useful in the management of wound infection through a significant bacterial growth inhibition and an acceleration of wound healing process.

Antimicrobial use metrics and benchmarking to improve stewardship outcomes: methodology, opportunities, and challenges

Measurement of antimicrobial use before and after an intervention and the associated outcomes are key activities of antimicrobial stewardship programs. In the United States, the recommended metric for aggregate antibiotic use is days of therapy/1000 patient-days. Clinical outcomes, including response to therapy and bacterial resistance, are critical measures but are more difficult to document than economic outcomes. Interhospital benchmarking of risk adjusted antimicrobial use is possible, although several obstacles remain before it can have an impact on patient care. Many challenges for stewardship programs remain, but the methods and science to support their efforts are rapidly evolving.

SIR, You've Led Me Astray!

Background.

The standardized infection ratio (SIR) is an indirectly standardized morbidity ratio that has been used to compare the infection rate in a hospital with an expected number of infections from a national standard and is being increasingly promoted as a metric for the public reporting of healthcare-associated infections (HAIs).

Objective.

To identify potential discrepancies between SIR and other measures of risk.

Methods.

Hypothetical and real data were compared using relative risk, a directly standardized morbidity ratio, and SIR values across a range of varying hospital population compositions.

Results.

In real and hypothetical data, other summary statistics were consistent with each other and with underlying HAI incidence density rates. However, use of the SIR frequently led to conclusions inconsistent with these other inherently unbiased estimators.

Conclusion.

Because of a recognized type of distortion inherent in the calculation of indirectly standardized ratios, use of the SIR can lead to conclusions that differ from those reached when using other traditional measures of risk and to incorrect assessments of conclusions about the performance of hospitals or states. In addition, the tendency to inappropriately arrange SIR values in rank order for comparison makes SIR unsuitable as a statewide metric for monitoring HAIs.

A, Naumova EN. Hospitalization records as a tool for evaluating performance of food- and water-borne disease surveillance systems: a Massachusetts case study

We outline a framework for evaluating food- and water-borne surveillance systems using hospitalization records, and demonstrate the approach using data on salmonellosis, campylobacteriosis and giardiasis in persons aged ≥65 years in Massachusetts. For each infection, and for each reporting jurisdiction, we generated smoothed standardized morbidity ratios (SMR) and surveillance to hospitalization ratios (SHR) by comparing observed surveillance counts with expected values or the number of hospitalized cases, respectively. We examined the spatial distribution of SHR and related this to the mean for the entire state. Through this approach municipalities that deviated from the typical experience were identified and suspected of under-reporting. Regression analysis revealed that SHR was a significant predictor of SMR, after adjusting for population age-structure. This confirms that the spatial “signal” depicted by surveillance is in part influenced by inconsistent testing and reporting practices since municipalities that reported fewer cases relative to the number of hospitalizations had a lower relative risk (as estimated by SMR). Periodic assessment of SHR has potential in assessing the performance of surveillance systems.

Post-discharge surveillance of wound infections by telephone calls method in a Sudanese Teaching Hospital

Surveillance of wound infections has been shown to be a powerful preventive tool, and feedback to the clinical staff reduces wound infection rates. The main objectives of this study were to identify the applicability of telephone calls as a method of post-discharge wound infection surveillance, and to identify patients and procedures characteristics associated with loss for follow-up after hospital discharge.

MATERIALS AND METHODS

This was a prospective cohort study conducted in Khartoum Teaching Hospital, Sudan. Patients, aged >18 years admitted for elective clean and clean-contaminated surgery during March 1st to 31st October 2010 were recruited. 1-month surveillance of wound infections was conducted with telephone interviews.

RESULTS

Overall 3656 patients were operated on. Of them 1769 (48.4%) were eligible {mean age 37.8+14 years; females, n=1472 (83.3%)}. The performed surgical interventions were 1814. Of these 1277 (70.4%) were clean-contaminated and 537 (29.6%) were clean. Patients who successfully completed the follow-up were 1387 (78.4%), while 368 (20.8%) were lost, and 14 (0.8%) died. The percentage of male patients (85.3%) who successfully completed the follow-up was significantly higher than females (77.8%); (P=0.002). Wound infection was detected in 15 (0.8%) cases during hospital stay and 110 (6.2%) others after hospital discharge.

CONCLUSIONS

The majority of wound infections in the current study appeared in post-discharge period; this emphasis the need for establishment of surveillance program in the hospital. Surveillance of wound infections using telephone calls is applicable in this setting and can be used as an alternative method to clinic-based diagnosis of wound infections.

Potential role of statins on wound healing: review of the literature

Wound healing is a dynamic and complex biological process, which requires coordinated events including haemostasis, inflammation, proliferation, revascularisation and remodelling. Impaired wound healing is a common problem that occurs in both community and hospital settings. Various experimental and clinical studies have evaluated different modalities for the treatment of topical wounds, such as sugar, antibiotics, honey and phytotherapies; also statins have diverse pleiotropic effects that have been suggested to be useful to improve wound healing. Data derived from both animal and human studies showed that statins especially atorvastatin, simvastatin and pravastatin can accelerate the wound-healing process. However, further high-quality and evidence-based studies are needed to address the best statin drug, appropriate dose, the best administration route, duration of treatment and to determine correlation between pleiotropic effects of statins and their probable clinical benefits.

[Multicentre study of infection incidence in knee prosthesis]

OBJECTIVE

To determine the incidence of surgical site infection in knee prosthesis surgical procedure for a follow-up period of one year in twelve hospitals in Madrid region.

MATERIAL AND METHOD

A prospective study was carried out from January to December 2009 using a national surveillance system called Indicadores Clínicos de Mejora Continua de Calidad. Primary and revision knee joint replacements in patients operated on in the previous year were included. Criteria used to define surgical site infection and patient risk index categories were those established by the Centers for Disease Control and Prevention and National Nosocomial Infections Surveillance. The incidence rates were worked out crude and adjusted by hazard ratio.

RESULTS

2,088 knee prosthesis procedures were analyzed. The overall incidence of surgical site infection was 2.1%. Sixty-five percent of the infections were organ/space. Sixty percent of the infections were identified in the early postoperative period. Of all surgical site infections, 41.9% were microbiologically confirmed. Antibiotic prophylaxis was implemented correctly in 63.3% of the cases. The most important cause of inappropriate prophylaxis was an unsuitable duration in 85.7% of the cases. The presurgical preparation was carried out correctly in 50.3% of surgical operations. The incidence of knee arthroplasty infection was twice as high as in the National Healthcare Safety Network and similar to national rates.

DISCUSSION

In this study, the incidence of infection was within the range of infection rates in other published European studies. Surveillance and control strategies of health care for associated infections allow us to assess trends and the impact of preventive measures.

Outcome of a strategy to reduce surgical site infection in a tertiary-care hospital

BACKGROUND

Surgical site infection (SSI) is a preventable complication. Achieving a zero SSI rate for all clean operations should be the goal of all surgeons.

AIM

We aimed to reduce our SSI rate by 50% for patients undergoing elective gastrointestinal and hernia operations.

METHODS

The study was conducted in a tertiary-care hospital department of surgery from January 2006 to December 2007 for all clean and clean-contaminated elective gastrointestinal and hernia operations. Four interventions targeted at reducing SSI were implemented in January 2006: Use of clippers instead of shavers for surgical site hair removal; standardized prophylactic antibiotic regimen and antibiotic administration within 30 min before incision; standardized glucose monitoring for diabetics; and maintenance of postoperative normothermia. Prospective data were collected and compared with historical data from January to December 2005.

RESULTS

A total of 2,408 patients underwent elective gastrointestinal and hernia operations from January 2006 to December 2007. After implementation, we were able to achieve 91%, 87%, 89%, and 76% overall compliance with the respective interventions, but postoperative normothermia was achieved in only 44% of our patients. With the bundle of interventions, our overall SSI rate was reduced from 3.1% to 0.5% (p < 0.001), an 84% reduction within two years. The incidence of SSI was 1.7% in colorectal operations, 1.2% in upper gastrointestinal operations, 0.3% in hepatopancreaticobiliary operations, and zero in inguinal and ventral hernia operations. The estimated cost saving for both the patients and the hospital was S$208,562 (US$147,967).

CONCLUSIONS

Surgical site infections could be reduced with the bundle of interventions. With these encouraging results, the good practices should be sustained and promulgated. Such a SSI prevention program must be embedded in the work processes for all surgical disciplines.

The Spanish national health care-associated infection surveillance network (INCLIMECC): data summary January 1997 through December 2006 adapted to the new National Healthcare Safety Network Procedure-associated module codes

BACKGROUND

In 1997, a national standardized surveillance system (designated INCLIMECC [Indicadores Clínicos de Mejora Continua de la Calidad]) was established in Spain for health care-associated infection (HAI) in surgery patients, based on the National Nosocomial Infection Surveillance (NNIS) system. In 2005, in its procedure-associated module, the National Healthcare Safety Network (NHSN) inherited the NNIS program for surveillance of HAI in surgery patients and reorganized all surgical procedures.

METHODS

INCLIMECC actively monitors all patients referred to the surgical ward of each participating hospital. We present a summary of the data collected from January 1997 to December 2006 adapted to the new NHSN procedures.

RESULTS

Surgical site infection (SSI) rates are provided by operative procedure and NNIS risk index category. Further quality indicators reported are surgical complications, length of stay, antimicrobial prophylaxis, mortality, readmission because of infection or other complication, and revision surgery.

CONCLUSION

Because the ICD-9-CM surgery procedure code is included in each patient's record, we were able to reorganize our database avoiding the loss of extensive information, as has occurred with other systems.

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.

Predictors of surgical site infection in dirty urological surgery

OBJECTIVES

Risk factors for surgical site infection (SSI) following urologic dirty operations have not been clearly identified. This study was conducted to describe incidence, potential risk factors and common causative pathogens of the SSI in such operations.

METHODS

Medical records of patients who had undergone simple nephrectomy or lumbotomy for suppurative renal infection at our institutions from 1999 to 2006 were retrospectively evaluated. The following data were retrieved: presence of SSI, demographic data, laboratory findings, comorbidities, microbiological data, type of renal suppuration, type of urological surgery and antibiotic regimen. Risk factors for SSI were evaluated using the multiple logistic regression model.

RESULTS

Sixty-five patients (mean age 55.6 +/- 13.1 years) were eligible for data analysis. In 20 of them (30.8%) a SSI was identified. The most common isolated pathogens were gram-negative bacteria. At univariate logistic regression analysis risk factors significantly associated with SSI included: presence of emphysematous infection, hypoalbuminemia, number of predisposing conditions, emergency operations, isolation of Enterobacteriaceae, positive pus culture. The use of trimethoprim/sulfamethoxazole was associated with a decreased risk for SSI. Multiple logistic model identified only the emergency operations and isolated Enterobacteriaceae as independent predictors of SSI (odds ratio [OR] = 11.1) (95% confidence interval [CI] = 3.0-40.8) and OR = 3.9 (1.0-14.8), respectively.

CONCLUSIONS

Patients with suppurative renal infections are submitted to life-saving emergency surgery. Urological surgeons should keep in mind that this carries a high risk for subsequent SSI. Effective preventive measures in these circumstance cannot be identified. Further research in this area is necessary to clarify this issue.

[Effect of surveillance on surgical site infection rate in knee and hip arthroplasty]

OBJECTIVE

To determine whether continuous surveillance of hospital-associated infections with regular feedback to the staff reduces the infection rate in orthopedic surgery.

MATERIAL AND METHODS

Prospective surveillance in two time periods in an orthopedic surgery department at a Spanish university hospital. Two infection control nurses and an epidemiologist surveyed all patients over a 3-year period for infections and potential risk factors. After an initial 24-month period (period A), surveillance for 12 months was conducted (period B). Between them adherence to recommendations was reinforced.

MAIN RESULTS

A total of 1,088 patients were surveyed. In period A, 3.3% of all operations were followed by an infection, compared with 2.0% in period B (p = 0.14). Adherence to recommended schedule of surgical prophylaxis increased from 8.7% in the first year to 32.7% in the last year (p < 0,001). We also determined the NNIS (National Nosocomial Infections Surveillance) index risk in 383 patients, the NNIS index-risk 2 being more frequent in period A (16.8%) than in period B (5.4%) (p<0.001). Renal failure frequency was higher in period A (3.4% vs. 1.6%; p = 0.04). However, diabetes and neoplasms were the same in both periods. In period B, chronic obstructive pulmonary disease (COPD) (14.6 vs. 11.0; p = 0.05) and obesity (12.8 vs. 10.3; p = 0.12) predominated. The means for surgical intervention, hospital stay, and age, were very similar in both periods.

CONCLUSIONS

Surveillance of hospital-associated infections including regular feedback to the staff is accompanied by a reduction in infection rates, possibly with lower cost and most patient safety. Therefore, such a surveillance program for orthopedic surgery department seems to be beneficial.

Efecto de la vigilancia sobre la tasa de infección de la herida quirúrgica en prótesis de cadera y rodilla

OBJECTIVE

To determine whether continuous surveillance of hospital-associated infections with regular feedback to the staff reduces the infection rate in orthopedic surgery.

MATERIAL AND METHODS

Prospective surveillance in two periods of time in an orthopedic surgery department at a Spanish university hospital. Two infection control nurses and an epidemiologist surveyed all patients over a 3-year period for infections and potential risk factors. After an initial 24-month period (period A), surveillance for 12 months was conducted (period B). Between these periods, adherence to recommendations was reinforced.

RESULTS

A total of 1,088 patients were surveyed. In period A, 3.3% of all operations were followed by an infection, compared with 2.0% in period B (p = 0.14). Adherence to recommended schedule of surgical prophylaxis increased from 8.7% in the first year to 32,7% in the last year (p = 0.001). We also determined the NNIS (National Nosocomial Infections Surveillance) index risk in 383 patients, with the NNIS index-risk 2 as more frequent in period A (16.8%) than the period B (5.4%) (p < 0.001). Renal failure frequency was higher in period A (3.4% vs. 1.6%; p = 0.04). However, diabetes and neoplasms were the same in both periods. In period B, chronic obstructive pulmonary disease (14.6 vs. 11.0; p = 0.05) and obesity (12.8 vs. 10.3; p = 0.12) predominated. The means for surgical intervention, hospital stay, and age, were very similar in both periods.

CONCLUSIONS

Surveillance of hospital-associated infections including regular feedback to the staff is accompanied by a reduction in infection rates, possibly with lower cost and more patient safety. Thus, such a surveillance program for orthopedic surgery department seems to be beneficial.

Simvastatin improves the healing of infected skin wounds of rats

PURPOSE: This study explores the potential of the simvastatin to ameliorate inflammation and infection in open infected skin wounds of rats. METHODS: Fourteen Wistar rats weighing 285±12g were used. The study was done in a group whose open infected skin wounds were treated with topical application of sinvastatina microemulsion (SIM, n=7) and a second group with wounds treated with saline 0.9 % (SAL, n=7). A bacteriological exam of the wounds fluid for gram positive and gram negative bacteria, the tecidual expression of TNFá and IL-1â by imunohistochemical technique, and histological analysis by HE stain were performed. RESULTS: The expression of TNFa could be clearly demonstrated in lower degree in skin wounds treated with simvastatin (668.6 ± 74.7 ìm²) than in saline (2120.0 ± 327.1 ìm²). In comparison, wound tissue from SIM group displayed leukocyte infiltration significantly lower than that observed in SAL group (p<0.05). Culture results of the samples taken from wound fluid on fourth post treatment day revealed wound infection in only one rat of group simvastatin (SIM), where Proteus mirabilis, Escherchia coli and Enterobacter sp were isolated. In the rats whose wounds were treated with saline (SAL), polymicrobial infection with more than 100,000 CFU/g was detected in all the wounds. CONCLUSION: In addition to its antiinflammatory properties, the protective effects of simvastatin in infected open skin wounds is able to reduce infection and probably has antibacterial action. The potential to treat these wounds with statins to ameliorate inflammation and infection is promising.

[Surgical site infection in general surgery: 5-year analysis and assessment of the National Nosocomial Infection Surveillance (NNIS) index]

INTRODUCTION

The aim of this study was to describe the rate of surgical site infections (SSI), classified according to the NNIS index and its components, as well as to evaluate this scale and assess the importance of several factors that influence the development of an SSI.

PATIENTS AND METHOD

All episodes of SSI were prospectively registered over a 5-year period. All patients (infected or not) were given an NNIS index and an NNIS category. Postoperative hospital stay and bacteria cultured from the surgical site were also analyzed. Chi2 test, Student's t-test and multiple logistic regression were used.

RESULTS

There were 6,218 patients and 513 SSI (8.25%). The infection rate was 2.27% for clean surgery, 9.17% for clean-contaminated surgery, 11.40% for contaminated surgery, and 19.14% for dirty surgery; 4% for ASA I, 8.23% for ASA II, 13.54% for ASA III, 19.55% for ASA IV, and 33.33% for ASA V; 6.97% for length of procedure = 75th percentile, and 23.01% for > 75th percentile; 3.95% for NNIS 0, 8.17% for NNIS 1, 22.08% for NNIS 2, and 37.23% for NNIS 3. Among the components of the NNIS index, the length of the surgical procedure had the greatest influence on the rate of SSI (OR = 3.43 versus OR = 2.60 for the grade of contamination and OR = 2.20 for ASA index). The infection rates according to the type of intervention were: 30.9% in hepatobiliopancreatic surgery, 24.3% in small bowel surgery, 16.1% in colorectal surgery, 15.4% in gastroduodenal surgery; 8.5% in other soft tissue interventions, 7.7% in exploratory laparotomies, 6.4% in appendicectomies for appendicitis, 5.0% in cholecystectomy, 5.0% in other interventions of the digestive tract, 3.3% in breast surgery, 1.5% in herniorrhaphies, and 0.7% in endocrine surgery.

CONCLUSIONS

The NNIS index is a valid instrument for classifying surgical patients according to the risk of developing an SSI. Of the three components, the length of the intervention has the greatest influence on increasing the risk of infection. The NNIS categories also distinguish different levels of risk of infection.

Impact of surgeon-specific feedback on surgical site infection rates in Thailand

Data on surgeon-specific feedback on surgical site infection (SSI) rates are not currently available in Thailand. The authors conducted a before and after study among patients undergoing surgery in seven Thai hospitals to examine whether a feedback system to surgeons could reduce SSI rates. After a six-month surveillance period, surgeons were provided with their own SSI rates and standardized infection ratios (SIRs). The criteria of the National Nosocomial Infection Surveillance (NNIS) system were used to determine SSI rates, and the SSI rates were compared with the NNIS report in terms of the SIR. To compare the SIR before and after intervention, the SIR ratio was calculated and logistic regression analysis was used to estimate the relative impact of surgeon-specific feedback, adjusting for patient sex, patient age, degree of wound contamination, American Society of Anesthesiologists' score, duration of operation, type of operation, use and duration of antibiotic prophylaxis, and length of pre-operative stay. After confidential feedback to surgeons for six months, SSI rates and the SIR remained unchanged. The SSI rate in the pre-intervention period was 1.7 infections/100 operations and the corresponding SIR was 0.8 [95% confidence intervals (CI)=0.6-0.9]. In the post-intervention period, the SSI rate was 1.8 infections/100 operations, with a corresponding SIR of 0.8 (95%CI=0.7-0.9). The SIR ratio was 1.0. The relative risk of SSI after surgeon-specific feedback suggested that this intervention had no effect (adjusted relative risk=1.02, 95%CI=0.77-1.35). Feedback to surgeons on their SSI rates did not reduce the rates of such infections in Thailand.

A practical tool to assess the incidence of nosocomial infection in Japanese intensive care units: the Japanese Nosocomial Infection Surveillance System

SUMMARY

Infection control professionals have the means to calculate infection rates in their hospitals but not to assess them. They require a practical tool that enables them to compare observed infection rates with external standards. Based on the data obtained from the intensive care unit (ICU) component of the Japanese Nosocomial Infection Surveillance (JANIS) system, a spreadsheet was developed to calculate a standardized infection ratio (SIR) as a risk-adjusted indicator. Out of the factors associated with the development of nosocomial infections in a multi-variate analysis, the following three factors were selected for stratification: APACHE II score (0-10, 11-20, 21+), operation (yes, no) and ventilator use (user, non-user). Infection rates in 2001 were determined (per 1000 patient-days), stratified by the three factors, as a benchmark. The spreadsheet was designed to calculate SIRs on the basis of the Japanese benchmark infection rates using Microsoft Excel software. The user of the spreadsheet should input the number of observed nosocomial infections and patient-days by APACHE II score, operation and ventilator use. When applied to eight Japanese ICUs, the spreadsheet revealed relative differences and temporal changes in the incidence of nosocomial infections within these ICUs.

[Quality improvement program of nosocomial infection in colorectal cancer surgery]

BACKGROUND AND OBJECTIVE

The surgical-site infection (SSI) is a complication of colorectal neoplasia surgery. The objectives of the study were to identify the SSI risk factors associated with colon surgery and to describe a strategy of quality improvement using surgical-site rates.

PATIENTS AND METHOD

Prospective cohort study of in-patients undergoing neoplasia colorectal surgery between 1st July 2002 to 30th June 2003. A descriptive analysis was implemented. Benchmarking was used as tool of quality improvement, and the outcomes were measured using the standardized infection ratio (SIR). To define the risk factors, the Chi square test and logistic regression test were used in univariate and multivariate analysis, respectively.

RESULTS

148 patients were included in the study. The SSI accumulative incidence rate (IA) was 10.14%, and the incidence rate was 6.47 SSI per 1000 days. The SIR was 1.53 the first semester and 1.02 the second one. The multivariate analysis identified two risk factors associated with SSI: unscheduled admission (odds ratio [OR] = 7.47, 95% confidence interval [CI] 2.03-27.48) and a risk index of American Society of Anaesthesiologists (ASA) > or = 3 (OR = 6.77, IC 95%, 1.15-39.84).

CONCLUSIONS

An unscheduled admission and high risk ASA index were risk factors associated with SSI in patients undergoing colorectal surgery. The program of quality improvement based on benchmark achieved a reduction of SSI rates similar to the standard ones.

Standardized incidence rates of surgical site infection: a multicenter study in Thailand

BACKGROUND

No previous multicenter data regarding the incidence of surgical site infection (SSI) are available in Thailand. The magnitude of the problem resulting from SSI at the national level could not be assessed. The purpose of this study was to estimate the incidence of SSI in 9 hospitals, together with patterns of surgical antibiotic prophylaxis, risk factors for SSI, and common causative pathogens.

METHODS

A prospective data collection among patients undergoing surgery in 9 hospitals in Thailand was conducted. The National Nosocomial Infection Surveillance (NNIS) system criteria and method were used for identifying and diagnosing SSI. The SSI rates were benchmarked with the NNIS report by means of indirect standardization and reported in terms of standardized infection ratio (SIR). Antibiotic prophylaxis was categorized into preoperative, intraoperative, and postoperative. Risk factors for SSI were evaluated using multiple logistic regression models.

RESULTS

From July 1, 2003, to February 29, 2004, the study included 8764 patients with 8854 major operations and identified 127 SSIs, yielding an SSI rate of 1.4 infections/100 operations and a corresponding SIR of 0.6 (95% CI: 0.5-0.8). Of these, 35 SSIs (27.6%) were detected postdischarge. The 3 most common operative procedures were cesarean section, appendectomy, and hysterectomy. The 3 most common pathogens isolated were Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, which accounted for 15.3%, 8.5%, and 6.8% of infections, respectively. The 3 most common antibiotics used for prophylaxis were ampicillin/amoxicillin, cefazolin, and gentamicin. The proportion of types of antibiotic prophylaxis administered were 51.6% preoperative, 24.3% intraoperative, and 24.1% postoperative. Factors significantly associated with SSI were high degree of wound contamination, prolonged preoperative hospital stay, emergency operation, and prolonged duration of operation.

CONCLUSION

Overall SSI rates were less than the average NNIS rates. The causative pathogens of SSI were different from those of other reports. There was a crucial proportion of operations that did not comply with the antibiotic guidelines. The risk factors for SSI identified in this study were consistent with most other reports.