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

A comparison between different suture techniques in lumbar spine surgery

As a result of solicited muscles, strong friction, and tensile force on cutaneous tissue, the difference in closure procedure and management strategies and complications of surgical incision healing is a real challenge in lumbar spine surgery. We performed a retrospective study to compare different types of wound closure in lumbar spine surgery. 4383 patients were included in this study. Wound dehiscence was more common in the intracutaneous suture group than in the far- near-near-far suture group. Delayed wound healing occurred more in the far-near near-far suture group than intracutaneous suture group. Also, the far-near near-far interrupted point suture group showed a higher ratio of delayed wound healing compared with crossover suture. The superficial wound infection rate was roughly the same in all types of sutures with an average value of 0.79% with 0.81% SD. This is a preliminary study to compare different types of operative wounds showing the pros and cons related to each option.

[Evaluation of compliance with the antibiotic prophylaxis protocol in hysterectomy. Prospective cohort study]

Objetivo

Las infecciones relacionadas con la asistencia sanitaria (IRAS) son un problema de salud pública, siendo las infecciones de localización quirúrgica (ILQ) las más frecuentes a nivel hospitalario. El objetivo de este estudio fue evaluar el efecto de la adecuación de la profilaxis antibiótica en la incidencia de infección quirúrgica en pacientes histerectomizadas.

Material y métodos

Se realizó un estudio de cohortes prospectivo entre octubre de 2009 y diciembre de 2018. Se estudió la incidencia de ILQ durante los primeros 30 días tras la cirugía. Se evaluó el grado de adecuación de la profilaxis antibiótica en histerectomía y el efecto de su inadecuación en la incidencia de infección con el riesgo relativo (RR) ajustado mediante un modelo de regresión logística.

Resultados

Se estudiaron 1.025 intervenciones en 1.022 mujeres. La incidencia acumulada de ILQ fue del 2,1% (n=22) y la etiología más frecuente Escherichia coli (23,1%) y Proteus mirabilis (23,1%). La profilaxis antibiótica estaba indicada en 1.014 intervenciones (98,9%) administrándose en 1.009 de ellas (99,5%), con una adecuación general al protocolo del 92,5%. La causa principal de no cumplimiento fue el tiempo de inicio (40,9%), seguida por la elección del antibiótico (35,2%). El efecto de la inadecuación de la profilaxis sobre la incidencia de infección fue de RR=0,9; IC95% 0,2-3,9; p>0,05.

Conclusiones

La adecuación de la profilaxis antibiótica fue muy alta, con una baja incidencia de infección quirúrgica. No se encontró asociación entre adecuación de la profilaxis e incidencia de infección en histerectomía. Se debe insistir en la mejora continua de la vigilancia epidemiológica en ginecología.

Surgical site infection following cesarean section in a general hospital in Kuwait: trends and risk factors

Surgical site infections (SSI) are a significant cause of post-surgical morbidity and mortality. The objectives of this study were to determine the prevalence of SSI and identify risk factors for infections following cesarean section (CS). A prospective study of SSI after CS was carried out from January 2014 to December 2016 using the methodology of the American National Nosocomial Infection Surveillance System. Suspected SSIs were confirmed clinically by the surgeon, and or, by culture. Seven thousand two hundred thirty five CS were performed with an overall SSI prevalence of 2.1%, increasing from 1.7% in 2014 to 2.95% in 2016 (P = 0.010). Of 152 cases of SSI, the prevalence of infection was 46.7% in women ⩽30 years and 53.3% in women >30 years (P = 0.119). Of 148 culture samples from as many women, 112 (75.7%) yielded growth of microorganisms with 42 (37.5%) of isolates being multi-drug resistant (MDR). Women who did not receive prophylactic antibiotics (35.5%) developed SSI more often than those who did (P < 0.0001). These findings suggest that emergency CS and inappropriate antibiotic prophylaxis are risk factors for developing SSI. In the light of the emergence of MDR bacteria there is a need to implement revised prophylactic antibiotic policy as part of antimicrobial stewardship to decrease SSI rates.

Magnitude and Determinant Factors of Surgical Site Infection in Suhul Hospital Tigrai, Northern Ethiopia: A Cross-Sectional Study

BACKGROUND

Surgical site infections (SSIs) are the most common hospital-acquired infection among surgical patients and remains a major clinical issue. In Ethiopia, despite many studies, the magnitude and associated factors of SSIs are not well documented and differ among regions. The aim of this study was to identify the magnitude and associated factors of SSIs in Suhul Hospital, Northern Ethiopia.

METHODS

An institution-based cross-sectional study was conducted from February 2-March 31, 2016, in Shire Suhul Hospital. A total of 280 post-operative patients were included and were selected using simple random sampling. A pre-tested interviewer administrated the questionnaire used to collect relevant information. Data were cleaned, entered, and analyzed using SPSS Version 20. Bivariable and multivariable logistic regression was employed to identify the predictors at p < 0.05.

RESULTS

Of the 281 potential study subjects, 280 participated. The mean age of the study subjects was 34.5 years (standard deviation [SD} ±15.6). The prevalence of SSI was 11.1% (95% confidence interval [CI] 7.34-14.67), and in the multivariable logistic regression analysis, four independent determinants emerged as associated with SSI: post-operative hospital stay from 8-14 days (odds ratio [OR] 7.97; 95% CI 1.70-37.38); history of alcohol use (OR 0.04; 95% CI 0.004-0.43); use of local anesthesia (OR 8; CI 1.010-63.398); and dirty incision classification (OR 17; CI 1.249-232.362).

CONCLUSION

The magnitude of SSI was high. A hospital stay for more than a week, a history of alcohol consumption, use of local anesthesia, and dirty incision classification were associated independently with a higher risk of SSI. Due attention should be given to infection prevention control methods; and more has to be done to manage dirty and contaminated sites, maintain a strict sterile environment and aseptic surgical techniques, and implement the World Health Organization surgical safety protocol. Efforts should be made to improve appropriate and timely discharge among surgical clients. Prospective longitudinal studies ought to be conducted considering SSI after hospital discharge.

An Assessment Scale for Patients with Postoperative Superficial Incisional Surgical Site Infection: a Cross-Sectional Study

Superficial incisional surgical site infection (SSI) is a common postoperative complication in surgical patients. The aim of this study was to assess the predictive power of an assessment scale for identifying patients at risk of superficial incisional SSI. A cross-sectional survey was conducted at the Department of Surgery at the Medical Research Institute Hospital, Alexandria University. A sample of 150 adult patients aged from 18 to 65 years, who undergoing general surgeries that had clean sutured surgical wounds, was randomly selected. Forty-six patients (30.7%) had SSI. The total score can significantly discriminate between positive and negative superficial incisional SSI patients with diagnostic accuracy of AUC (SE) = 0.66 (0.048). Each score more than the cutoff point (11.5) will increase the risk of surgical site infection development by 2.5 times (OR (95% CI) = 2.5 (1.26-3.1)). The developed assessment scale can discriminate between patients who are at risk of superficial incisional SSI and those who are not. It can be used as a preliminary screening tool for subsequent investigation for the presence of infection.

Patient Self-Assessment of Surgical Site Infection is Inaccurate

BACKGROUND

Availability of surgical site infection (SSI) surveillance rates challenges clinicians, healthcare administrators and leaders and the public. The purpose of this report is to demonstrate the consequences patient self-assessment strategies have on SSI reporting rates.

METHODS

We performed SSI surveillance among patients undergoing general surgery procedures, including telephone follow-up 30 days after surgery. Additionally we undertook a separate validation study in which we compared patient self-assessments of SSI with surgeon assessment. Finally, we performed a meta-analysis of similar validation studies of patient self-assessment strategies.

RESULTS

There were 22/266 in-hospital SSIs diagnosed (8.3%), and additional 16 cases were detected through the 30-day follow-up. In total, the SSI rate was 16.8% (95% CI 10.1-18.5). In the validation survey, we found patient telephone surveillance to have a sensitivity of 66% (95% CI 40-93%) and a specificity of 90% (95% CI 86-94%). The meta-analysis included five additional studies. The overall sensitivity was 83.3% (95% CI 79-88%), and the overall specificity was 97.4% (95% CI 97-98%). Simulation of the meta-analysis results divulged that when the true infection rate is 1%, reported rates would be 4%; a true rate of 50%, the reported rates would be 43%.

CONCLUSION

Patient self-assessment strategies in order to fulfill 30-day SSI surveillance misestimate SSI rates and lead to an erroneous overall appreciation of inter-institutional variation. Self-assessment strategies overestimate SSIs rate of institutions with high-quality performance and underestimate rates of poor performance. We propose such strategies be abandoned. Alternative strategies of patient follow-up strategies should be evaluated in order to provide valid and reliable information regarding institutional performance in preventing patient harm.

The efficacy of ampicillin compared with ceftriaxone on preventing cesarean surgical site infections: an observational prospective cohort study

Background

Cesarean surgical site infections (SSIs) can be prevented by proper preoperative antibiotic prophylaxis. Differences in antibiotic selection in clinical practice exist according to obstetricians’ preferences despite clear guidelines on preoperative antibiotic prophylaxis. This study aimed to compare the efficacy of ampicillin and ceftriaxone in preventing cesarean SSIs.

Methods

The observational prospective cohort study was conducted at a tertiary hospital in Thailand from 1 January 2007 to 31 December 2012. Propensity scores for ceftriaxone prophylaxis were calculated from potential influencing confounders. The cesarean SSI rates of the ceftriaxone group vs. those of the ampicillin prophylactic group were estimated by multilevel mixed-effects Poisson regression nested by propensity score.

Results

Data of 4149 cesarean patients were collected. Among these, 911 patients received ceftriaxone whereas 3238 patients received ampicillin as preoperative antibiotic prophylaxis. The incidence of incisional SSIs was (0.1% vs. 1.2%; p = 0.001) and organ space SSIs was (1.2% vs. 2.9%; p = 0.003) in the ceftriaxone group compared with the ampicillin group. After adjusting for confounders, the rate ratios of incisional and organ/space SSIs in the ceftriaxone compared with the ampicillin group did not differ (RR, 0.23; 95% CI 0.03–1.78), and (RR, 1.62; 95% CI 0.83–3.18), respectively.

Conclusion

These data indicate no difference exists between ampicillin and ceftriaxone to prevent SSIs after cesarean section. Ampicillin may be used as antibiotic prophylaxis in cesarean section.

Electronic supplementary material

The online version of this article (10.1186/s13756-018-0304-6) contains supplementary material, which is available to authorized users.

[Effect of compliance with an antibiotic prophylaxis protocol in surgical site infections in appendectomies. Prospective cohort study]

BACKGROUND

Antibiotic prophylaxis is the most suitable tool for preventing surgical site infection. This study assessed compliance with antibiotic prophylaxis in surgery for acute appendicitis, and the effect of this compliance on surgical site infection.

MATERIAL AND METHODS

Prospective cohort study to evaluate compliance with antibiotic prophylaxis protocol in appendectomies. An assessment was made of the level of compliance with prophylaxis, as well as the causes of non-compliance. The incidence of surgical site infection was studied after a maximum incubation period of 30 days. The relative risk adjusted with a logistic regression model was used to assess the effect of non-compliance of prophylaxis on surgical site infection.

RESULTS

The study included a total of 930 patients. Antibiotic prophylaxis was indicated in all patients, and administered in 71.3% of cases, with an overall protocol compliance of 86.1%. The principal cause of non-compliance was time of initiation. Cumulative incidence of surgical site infection was 4.6%. No relationship was found between inadequate prophylaxis compliance and infection (relative risk=0.5; 95% CI: 0.1-1.9) (P>.05).

CONCLUSIONS

Compliance of antibiotic prophylaxis was high, but could be improved. No relationship was found between prophylaxis compliance and surgical site infection rate.

Risk factors for cesarean surgical site infections at a Thai-Myanmar border hospital

BACKGROUND

Cesarean surgical site infections (SSIs) are a major challenge in Thai-Myanmar border hospital settings. This study aimed to examine risk factors for SSIs after cesarean section.

METHODS

This was a prospective cohort study conducted in a Thai-Myanmar border hospital between January 2007 and December 2012. Data were collected from the medical record database by trained infection control nurses. Stepwise multivariable logistic regression was used for risk factor analysis and expressed as a risk ratio (RR).

RESULTS

The cesarean SSI rate was 5.9% (293 SSIs in 4,988 cases). Of these, 17.1% were incisional SSIs (10.9% superficial and 6.2% deep incisional SSIs), and 82.9% were organ or space SSIs. Risk factors for cesarean organ-space SSIs included a wound class ≥3 (RR, 4.82; 95% confidence interval [CI], 3.41-6.83), ethnic minority (RR, 2.51; 95% CI, 1.61-3.92), hemoglobin <11 g/dL (RR, 2.19; 95% CI, 1.57-3.04), pelvic examination before delivery on ≥5 occasions (RR, 4.16; 95% CI, 2.89-5.99), preterm (RR, 1.98; 95% CI, 1.33-2.95), being a local referral (RR, 3.37; 95% CI, 2.29-4.97), and foul-smelling amniotic fluid (RR, 21.08; 95% CI, 10.23-43.41).

CONCLUSIONS

Most cesarean SSIs in this study seem to have a high severity. Their risk factors reflected delayed appropriate perinatal maternal care that resulted in late cesarean delivery. Early prenatal care may help reduce cesarean SSIs among this population.

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.

Relationship of Gallbladder Perforation and Bacteriobilia with Occurrence of Surgical Site Infections following Laparoscopic Cholecystectomy

Aim. To assess the occurrence of SSIs in patients with spillage of gallbladder contents and bacteriobilia during laparoscopic cholecystectomy. Methods. We evaluated 113 patients who underwent laparoscopic cholecystectomy between September 2013 and April 2015. The SSIs and their relationship with gallbladder rupture and bacteriobilia were assessed. Results. The mean age of patients developing SSIs was 45.57 ± 8.89 years. 18 patients (16%) had spillage of bile from the gallbladder. Percentage of SSIs overall was 6%, while percentage of SSIs in gallbladder content spillage was 5.5%. Organism profile of the culture from surgical site showed monomicrobial infection: 58% Staphylococcus aureus, 14% Pseudomonas, and 14% E. coli. The occurrence of SSIs in patients with bacteriobilia was 16% as compared to 2% in patients without bacteriobilia. Conclusions. Gallbladder content spillage is not a significant risk factor leading to increase in SSIs. The occurrence of SSIs is significantly higher in patients with bacteriobilia.

A systematic review of risk factors associated with surgical site infections among surgical patients

IMPORTANCE

Surgical site infection (SSI) complicates 2-5% of surgeries in the United States. Severity of SSI ranges from superficial skin infection to life-threatening conditions such as severe sepsis, and SSIs are responsible for increased morbidity, mortality, and economic burden associated with surgery. Staphylococcus aureus (S. aureus) is a commonly-isolated organism for SSI, and methicillin-resistant S. aureus SSI incidence is increasing globally.

OBJECTIVE

The objective of this systematic review was to characterize risk factors for SSI within observational studies describing incidence of SSI in a real-world setting.

EVIDENCE REVIEW

An initial search identified 328 titles published in 2002-2012; 57 were identified as relevant for data extraction. Extracted information included study design and methodology, reported cumulative incidence and post-surgical time until onset of SSI, and odds ratios and associated variability for all factors considered in univariate and/or multivariable analyses.

FINDINGS

Median SSI incidence was 3.7%, ranging from 0.1% to 50.4%. Incidence of overall SSI and S. aureus SSI were both highest in tumor-related and transplant surgeries. Median time until SSI onset was 17.0 days, with longer time-to-onset for orthopedic and transplant surgeries. Risk factors consistently identified as associated with SSI included co-morbidities, advanced age, risk indices, patient frailty, and surgery complexity. Thirteen studies considered diabetes as a risk factor in multivariable analysis; 85% found a significant association with SSI, with odds ratios ranging from 1.5-24.3. Longer surgeries were associated with increased SSI risk, with a median odds ratio of 2.3 across 11 studies reporting significant results.

CONCLUSIONS AND RELEVANCE

In a broad review of published literature, risk factors for SSI were characterized as describing reduced fitness, patient frailty, surgery duration, and complexity. Recognition of risk factors frequently associated with SSI allows for identification of such patients with the greatest need for optimal preventive measures to be identified and pre-treatment prior to surgery.

Antimicrobial resistance in hospitalized surgical patients: a silently emerging public health concern in Uganda

Background

Surgical site infections (SSIs) are difficult to treat and are associated with substantially longer hospital stay, higher treatment cost, morbidity and mortality, particularly when the etiological agent is multidrug-resistant (MDR). To address the limited data in Uganda on SSIs, we present the spectrum of bacteria isolated from hospitalized patients, the magnitude and impact of MDR bacterial isolates among patients with SSIs.

Methods

A descriptive cross sectional study was conducted from September 2011 through April 2012 involving 314 patients with SSIs in the obstetrics & gynecology, general surgery and orthopedic wards at Mulago National Hospital in Kampala, Uganda. Wound swabs were taken and processed using standard microbiological methods. Clinico-demographic characteristics of patients were obtained using structured questionnaires and patients’ files.

Results

Of the 314 enrolled patients with SSIs (mean age 29.7 ±13.14 years), 239 (76.1%) were female. More than half of the patients were from obstetrics and gynecology (62.1%, 195/314). Of 314 wound swabs taken, 68.8% (216/314) were culture positive aerobically, yielding 304 bacterial isolates; of which 23.7% (72/304) were Escherichia coli and 21.1% (64/304) were Staphylococcus aureus. More than three quarters of Enterobacteriaceae were found to be extended spectrum beta lactamase (ESBL) producers and 37.5% of S. aureus were Methicillin resistant S. aureus (MRSA). MDR occurred in 78.3% (238/304) of the isolates; these were more among Gram-negative bacteria (78.6%, 187/238) compared to Gram-positive bacteria (21.4%, 51/238), (p-value < 0.0001, χ2 = 49.219). Amikacin and imepenem for ESBL-producing Enterobacteriacea and vancomycin for MRSA showed excellent performance except that they remain expensive drugs in Uganda.

Conclusion

Most SSIs at Mulago National Hospital are due to MDR bacteria. Isolation of MRSA and ESBL-producing Enterobacteriaceae in higher proportions than previously reported calls for laboratory guided SSIs- therapy and strengthening of infection control surveillance in this setting.

Risk factors for surgical site infections in abdominal surgery: a study in Nepal

BACKGROUND

Surgical site infection (SSI) remains a major clinical problem for developing countries in terms of morbidity, mortality, and hospital cost. Little is known about the epidemiology of SSI in Nepal. We conducted a study in Nepal to identify the various pre- and intra-operative risk factors for SSIs that are accessible to interventions.

METHODS

The study was a prospective study done on all eligible patients who underwent abdominal surgery in the surgical wards of Tribhuvan University Teaching Hospital (TUTH) in Kathmandu, Nepal, from January 2011 to June 2011. We evaluated some patient-related as well as intra-operative variables that could be risk factors for SSIs. We assessed the association between these risk factors and SSI with the Fisher exact test and logistic regression analysis.

RESULTS

Of the 230 patients included in the study, 53 were identified as having a SSI, resulting in an overall rate of SSI of 23%. Multivariable analysis identified the following factors as independent risk factors for SSI: (1) Low hemoglobin concentrations (<12 g/dL) (odds ratio [OR] 2.5; 95% confidence interval [CI] 1.1-6.1); (2) overweight (OR 7.6; 95% CI 2.1-27.0); and (3) surgery performed by residents (OR 3.4; 95% CI 1.4-8.3).

CONCLUSIONS

Surgical site infection is common among patients undergoing abdominal surgery at TUTH. This study identified some preventable risk factors associated with SSI at TUTH. Identification of such risk factors is expected to help surgeons improve patient care and decrease mortality and morbidity as well as the hospital-care cost of surgical patients.

Implementation of the World Health Organization surgical safety checklist at a university hospital in Thailand

BACKGROUND

Compliance with the World Health Organization (WHO) surgical safety checklist may reduce preventable adverse events. However, compliance may be difficult to implement in Thailand. This study was conducted to examine compliance with the WHO checklist at a Thai university hospital.

METHODS

A descriptive study was conducted among 4,340 patients undergoing surgery in nine departments from March to August 2009. The compliance rates were computed.

RESULTS

The highest compliance rate (91.4%) during the sign-in period was with patients' confirmation of their identity, operative site, procedure, and consent. However, only 19.4% of the surgical sites were marked. In the time-out period, surgical teams had introduced themselves by name and role in 79% of the operations; and in 95.7% of the cases, the patient's name, the incision site, and the procedure had been confirmed. Antibiotic prophylaxis had been given within 60 min before the incision in 71% of the cases. For 83% of the operations, the surgeons reviewed crucial events whereas only 78.4% were reviewed by the anesthetists. Sterility had been confirmed by the operating room nurses for every patient, but the essential imaging was displayed at a rate of only 64.4%. In the sign-out period, nurses correctly confirmed the name of the procedure orally in 99.5% of the cases. Instrument, sponge, and needle counts were completed and the specimen was labeled in most cases, 96.8% and 97.6%, respectively. Equipment-related problems were identified in 4.4% of the cases, and 100% of them were addressed. The surgeon, anesthetist, and nurse reviewed the key concerns for recovery and management of the patient at the rate of 85.1%.

CONCLUSIONS

The WHO checklist can be implemented in a developing country. However, compliance with some items was extremely low, reflecting different work patterns and cultural norms. Additional education and enforcement of checklist use is needed to improve compliance.

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.

Postdischarge surveillance following cesarean section: the incidence of surgical site infection and associated factors

BACKGROUND

The rate of surgical site infections (SSI) and their associated risk factors was identified by performing postdischarge surveillance following cesarean section at a public university teaching hospital in Brazil.

METHODS

The study was conducted at the Center for Women's Integrated Health Care in Brazil between May 2008 and March 2009. Women were contacted by telephone 15 and 30 days after cesarean section. During hospitalization, a form was completed on factors associated with post-cesarean SSI. The chi(2) test and Fisher exact test were used to analyze categorical variables and the Mann-Whitney test for numerical variables. Relative risks (RR) and their respective 95% confidence intervals (95% CI) were calculated for factors associated with SSI. P values < .05 were considered significant.

RESULTS

The final sample consisted of 187 women. SSI was detected in 44 cases (23.5%). In 42 of 44 women (95%), SSI appeared following discharge from hospital, becoming evident within the first 15 days following surgery. Number of prenatal consultations < or =7 (RR, 2.09; 95% CI: 1.26-3.48) and hypertension (RR, 2.07; 95% CI: 1.25-3.43) were significantly associated with SSI in the bivariate analysis. In the multivariate analysis, only hypertension (RR, 2.47; 95% CI: 1.21-5.04) remained significant.

CONCLUSION

Postdischarge surveillance is essential for ensuring accurate estimates of post-cesarean section SSI. A 15-day postdischarge follow-up was shown to be sufficient. Hypertension was a factor associated with SSI.

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.

Surgical site infections in orthopedic patients: prospective cohort study

AIM

To estimate the incidence rate and risk factors of surgical site infections in the orthopedic wards in a major teaching hospital in Serbia.

METHODS

A 6-month prospective cohort study, with 30 days of patient follow-up after surgery, was conducted at the teaching hospital in Belgrade. We collected patients' basic demographic data and data on underlying disease status, surgical procedures, preoperative preparation of patients, and antibiotic prophylaxis. The National Nosocomial Infections Surveillance (NNIS) risk index was computed for each patient. Descriptive and logistic regression analyses were performed to determine risk factors for surgical site infections.

RESULTS

Assessment of 277 patients after operation revealed surgical site infection in 63 patients. In 3 (4.8%) of them, surgical site infections were detected after hospital discharge. The overall incidence rate of surgical site infections was 22.7% (95% confidence interval [95% CI], 17.5-29.1). The incidence increased from 13.2% in clean wounds to 70.0% in dirty wounds. The rates of surgical site infection for the NNIS risk index classes 0 to 3 were 8.1% (13 of 161), 36.4% (32 of 88), 63.0% (17 of 27), and 100% (1 of 1) (P<0.001; chi2 test). Multivariate logistic regression analysis identified the following independent risk factors for surgical site infections: greater number of persons in the operating room (odds ratio [OR], 1.28; 95% CI, 1.02-1.60), contaminated or dirty wounds (OR, 12.09; 95% CI, 5.56-26.28), and American Society of Anesthesiologists' (ASA) score >2 (OR, 3.47; 95% CI, 1.51-7.95). In patients who were shaved with a razor, the period of 12 or more hours between shaving and intervention was also an independent risk factor (OR, 2.77; 95% CI, 1.22-6.28).

CONCLUSION

There is a high incidence of surgical site infections in orthopedic patients in Serbia in comparison with developed countries and some developing countries. Points for intervention could be reduction of personnel during surgery, better treatment of wounds, decreasing ASA score, and reduction of the time between surgical site shaving and the intervention.

Surgical Site Infections in Plastic Surgery: An Italian Multicenter Study

BACKGROUND

Plastic surgery interventions have increased in terms of frequency, complexity of surgical procedures, and postoperative complications, particularly surgical site infections (SSIs). The aim of the present study was to assess the SSI frequency in plastic and reconstructive surgery settings in Italy and to evaluate the associated risk factors.

METHODS

From June 2004 to June 2005, a prospective multicenter study including 2806 consecutive patients was conducted in 23 Italian plastic and reconstructive units. To assess potential risk factors for surgical site infection, a conditional logistic regression model was used and results were exposed in terms of odds ratio (OR) with their respective 95% confidence interval (CI).

RESULTS

SSIs occurred in 85/2806 (3%) patients. Sixty (70.6%), 24 (28.2%), and 1 (1.2%) SSIs were classified as superficial, deep, and organ/space, respectively. Sixty-six percent of the SSIs were diagnosed during postdischarge surveillance. At multivariate analysis, diabetes mellitus, chronic obstructive pulmonary disease, preoperative radiotherapy, and use of surgical drains were significantly associated with the occurrence of SSI.

CONCLUSIONS

Our findings, based on a large population including all types of plastic and reconstructive interventions, provided consistent information on potential risk factors for SSI in this surgical setting. Moreover, the high rate of SSI found during the postdischarge surveillance underlines the need for improving active surveillance methodologies in this surgical setting.

[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.

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

The aim of this study was to estimate temporal trends in the incidence of surgical site infection (SSI) using a large SSI surveillance network in southeast France from 1995 to 2003. Data were analysed from 187 surgical wards that had participated in the network for at least two years. The change in SSI rate over time was modelled using a hierarchical logistic regression model with patients clustered within surgical wards. Of the 200 207 patients selected, 3786 (1.9%) had an SSI. The nine-year trend in SSI rate estimated by an odds ratio of 0.95 (95% confidence interval 0.93-0.97) was interpreted as a 5% decrease in SSI rate per year. This decrease was constant over the study period and was observed for almost all of the different types of surgical operations (orthopaedic, gastrointestinal, urology, etc). Overall SSI rates were reduced by 45% over a period of nine years. This trend was maintained even when taking into account the heterogeneity of the surgical wards and the diversity of patient demographics over time. From this, the 5% decrease per year can be reasonably interpreted as a result of preventive measures taken by surgical wards to reduce SSIs.

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.

Bandages, dressings, and cranial neurosurgery

OBJECT

Bandages and dressings are commonly applied to incisional scalp wounds to prevent complications, particularly infection, during the early stages of wound healing. Bandaging cranial incisional wounds requires resources, consumes healthcare workers' time, and incurs expense; it is therefore important to examine its efficacy.

METHODS

All cranial operations (excluding shunt placements, procedures on the scalp alone, and bur hole procedures) performed between June 30, 2001 and January 1, 2006, by two neurosurgeons at either of two hospitals, one adult and one pediatric institution, were reviewed. Surgical site infections (SSIs) and other postoperative complications were investigated with respect to the use of bandaging for incisional wounds and other aspects of postoperative wound management. The operations were classified into four categories based on wound type: "clean," "clean-contaminated," "contaminated," and "dirty," according to the criteria of the Centers for Disease Control and Prevention.

CONCLUSIONS

A total of 702 operations were performed in 577 patients; only five patients received any type of surgical bandaging. There were four SSIs (0.57%; 95% confidence interval [CI] 0.16-1.45). The postoperative infection rate in the 626 clean cases was 0.48% (95% CI 0.10-1.39) and was 2.63% (95% CI 0.07-13.81) in the 38 clean-contaminated cases. The data obtained in this investigation is consistent with the position that bandaging incisional scalp wounds after cranial surgery adds little if any benefit beyond the easier, simpler, and cheaper practice of using antibiotic ointment as a dressing without bandaging.

Risk stratification for surgical site infections in Australia: evaluation of the US National Nosocomial Infection Surveillance risk index

This study evaluated the US National Nosocomial Infection Surveillance (NNIS) risk index (RI) in Australia for different surgical site infection (SSI) outcomes (overall, in-hospital, post-discharge, deep-incisional and superficial-incisional infection) and investigated local risk factors for SSI. A SSI surveillance dataset containing 43 611 records for 13 common surgical procedures, conducted in 23 hospitals between February 2001 and June 2005, was used for the analysis. The NNIS RI was evaluated against the observed SSI data using diagnostic test evaluation statistics (sensitivity, specificity, positive predictive value, negative predictive value). Sensitivity was low for all SSI outcomes (ranging from 0.47 to 0.69 and from 0.09 to 0.20 using RI thresholds of 1 and 2 respectively), while specificity varied depending on the RI threshold (0.55 and 0.93 with thresholds of 1 and 2 respectively). Mixed-effects logistic regression models were developed for the five SSI outcomes using a range of available potential risk factors. American Society of Anaesthesiologists (ASA) physical status score >2, duration of surgery, absence of antibiotic prophylaxis and type of surgical procedure were significant risk factors for one or more SSI outcomes, and risk factors varied for different SSI outcomes. The discriminatory ability of the NNIS RI was insufficient for its use as an accurate risk stratification tool for SSI surveillance in Australia and its sensitivity was too low for it to be appropriately used as a prognostic indicator.