Surgical site infections in ambulatory surgery: a 5-year experience

Surgical site infections after abdominal surgery: incidence and risk factors. A prospective cohort study

BACKGROUND

Abdominal surgeries have high rates of surgical site infections (SSIs), contributing to increased morbidity and mortality and costs for hospitalization. The aim of this study was to determine the SSI incidence rates and risk factors after abdominal surgeries.

METHODS

This prospective cohort study included all patients undergoing abdominal surgeries between 2005 and 2007 in the Western Galilee Medical Center in Nahariya, Israel. SSI incidence rates were calculated per 100 operations. Odds ratios (ORs) were estimated for each risk factor using univariate and multivariate analyses by logistic regression models.

RESULTS

Among 302 patients in the study cohort, the total SSI incidence rate was 22.2%. The univariate analysis defined 13 variables significantly associated with SSI: age > 60 years, lower functional status, diabetes mellitus, congestive heart failure, immunocompromising underlying disease, treatment with chemotherapy and other immunosuppressive medications, impaired immune system open cholecystectomy, laparotomy, an American Society of Anesthesiologists (ASA) score > 2, drain insertion, and 'dirty wound' classification. In multivariate regression analysis, treatment with immunosuppressive medications (OR = 2.5, 95% confidence interval (CI) = 1.099-143.443), open cholecystectomy (OR = 2.25, 95% CI = 2.242-40.109), and dirty wound classification (OR = 2.179, 95% CI = 3.80-20.551) were significantly associated with SSI.

CONCLUSIONS

The significant risk factors defined should be addressed preoperatively to decrease the risk for SSI. Wound surveillance in the post-discharge period is necessary for correct estimation of SSI rates.

Assessing surgical site infection risk factors using electronic medical records and text mining

Text mining techniques to detect surgical site infections (SSI) in unstructured clinical notes were used to improve SSI detection. In conjuction with data from an integrated electronic medical record, all of the 22 SSIs detected by traditional hospital-based surveillance were found using text mining, along with an additional 37 SSIs not detected by traditional surveillance.

Burden of endemic health-care-associated infection in developing countries: systematic review and meta-analysis

BACKGROUND

Health-care-associated infection is the most frequent result of unsafe patient care worldwide, but few data are available from the developing world. We aimed to assess the epidemiology of endemic health-care-associated infection in developing countries.

METHODS

We searched electronic databases and reference lists of relevant papers for articles published 1995-2008. Studies containing full or partial data from developing countries related to infection prevalence or incidence-including overall health-care-associated infection and major infection sites, and their microbiological cause-were selected. We classified studies as low-quality or high-quality according to predefined criteria. Data were pooled for analysis.

FINDINGS

Of 271 selected articles, 220 were included in the final analysis. Limited data were retrieved from some regions and many countries were not represented. 118 (54%) studies were low quality. In general, infection frequencies reported in high-quality studies were greater than those from low-quality studies. Prevalence of health-care-associated infection (pooled prevalence in high-quality studies, 15·5 per 100 patients [95% CI 12·6-18·9]) was much higher than proportions reported from Europe and the USA. Pooled overall health-care-associated infection density in adult intensive-care units was 47·9 per 1000 patient-days (95% CI 36·7-59·1), at least three times as high as densities reported from the USA. Surgical-site infection was the leading infection in hospitals (pooled cumulative incidence 5·6 per 100 surgical procedures), strikingly higher than proportions recorded in developed countries. Gram-negative bacilli represented the most common nosocomial isolates. Apart from meticillin resistance, noted in 158 of 290 (54%) Staphylococcus aureus isolates (in eight studies), very few articles reported antimicrobial resistance.

INTERPRETATION

The burden of health-care-associated infection in developing countries is high. Our findings indicate a need to improve surveillance and infection-control practices.

FUNDING

World Health Organization.

Myths and legends in orthopaedic practice: are we all guilty?

Over years of practice, many beliefs and practices become entrenched as tried and tested, and we subconsciously believe they are based on scientific evidence. We identified nine such beliefs by interviewing orthopaedic surgeons in which studies (or lack thereof) apparently do not support such practices. These are: changing the scalpel blade after the skin incision to limit contamination; bending the patient's knee when applying a thigh tourniquet; bed rest for treatment of deep vein thrombosis; antibiotics in irrigation solution; routine use of hip precautions; routine use of antibiotics for the duration of wound drains; routine removal of hardware in children; correlation between operative time and infection; and not changing dressings on the floor before scrubbing. A survey of 186 practicing orthopaedic surgeons in academic and community settings was performed to assess their routine practice patterns. We present the results of the survey along with an in-depth literature review of these topics. Most surgeon practices are based on a combination of knowledge gained during training, reading the literature, and personal experience. The results of this survey hopefully will raise the awareness of the selected literature for common practices.

[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.

Improved detection of orthopaedic surgical site infections occurring in outpatients

To test the hypothesis that a simple method of text searching of standard dictated outpatient clinic notes could be used to detect postoperative infections that otherwise were undetected by the traditional hospital-based infection surveillance methods, a retrospective analysis of all clinical notes from the orthopaedic surgery service of a tertiary care medical center without an electronic medical record system was done. Text-searching algorithms were used to screen all outpatient clinic notes for patients seen between September, 2000 and May, 2001. Clinic notes were screened using specific search terms indicative of surgical site infection, to yield a subset of notes that then were manually reviewed. The identified 18,887 notes were reduced to 558 screen-positive notes, of which 347 notes (197 patients) had confirmed surgical site infections on manual review (positive predictive value, 62.2%). Eighty percent of the total joint infections and 54% of the spine infections were not detected through standard hospital-based surveillance. This simple, inexpensive, method for screening clinic notes is effective in improving detection of postdischarge surgical site infections (and, therefore, quality assessment for surgery). It can be implemented in most current clinical settings.

LEVEL OF EVIDENCE

Diagnostic study, Level II-1 (development of diagnostic criteria on basis of consecutive patients--with universally applied reference gold standard). See the Guidelines for Authors for a complete description of levels of evidence.

[Incidence of surgical site infection in ambulatory surgery: results of the INCISCO surveillance network in 1999-2000]

OBJECTIVES

To estimate the incidence of surgical-site infections (SSI) in ambulatory surgery and to identify risk factors based on the surveillance network INCISO in 1999-2000.

PATIENTS AND METHODS

Annually, during a three-month period, each surgical ward had to include 200 consecutive operations. Patients were surveyed over the month following surgery. For each patient, data including peri-operative factors, type of procedure and SSI occurrence were collected on a standardized form by a surgical staff committed for the study.

RESULTS

Of the 5,183 patients who underwent an ambulatory surgery, the SSI incidence ratio was 0.4% (95% CI [0.3-0.7]). Orthopedic, gynecologic/obstetrics, head and neck, skin and soft tissues surgery accounted for 83% of all ambulatory procedures. 93% of patients belonged to the 0 risk category of the National Nosocomial Infections Surveillance system (NNIS) index. Emergency, age, american anesthesia risk score (ASA), Altemeier wound class, and procedure duration were not found to be risk factors for SSI in ambulatory surgery.

CONCLUSION

Based on these surveillance data, infectious risk was low in ambulatory surgery and was not associated with known SSI risk factors.