Economic impact of treatment for surgical site infections in cases of total knee arthroplasty in a tertiary public hospital in Brazil

Development of a perioperative thermal insulation system: Testing comfort properties for different textile sets

The poorly physical and psychological conditions of the patients make the body thermal protection crucial in the perioperative context, due to the risk of hypothermia. The lack of evidence regarding the effectiveness of textile coverings in protecting patients in the operating room, underscores the recommendation of the forced warming system using non-woven fabric for ensuring the best thermal protection in the perioperative context. This study is part of a development process of a three-layered thermal insulation system, a blanket for use in the perioperative context. After previous selection of two fabrics for the mid and outer layers, in this study three fabric samples for the inner layer with same soft tactile sensation and different textile compositions were tested to find its effect on increasing the thermal insulation of the whole set, using a thermal manikin. The serial method was used to calculate the thermal insulation properties of the sets. The best thermal insulation and thermal comfort performance was obtained by the set using an inner layer composed of polypropylene, polyamide, and elastane whose results were the highest thermal conductivity and thickness and the lowest maximum stationary heat flow density. The results indicated that this fabric influenced positively the values of the whole set once increased its thermal protection effectiveness when compared to the other tested sets. This set is more suitable for future testing in patients during their stay in the perioperative setting.

Infection after primary total knee arthroplasty: a randomized controlled prospective study of the addition of antibiotics to bone cement

Objective  The present prospective, randomized and controlled study was conducted with 286 patients submitted to primary total knee arthroplasty (TKA) with the objective of evaluating the efficacy of the addition of antibiotics to bone cement as a way to prevent post arthroplasty infection (PAI).

Methods  The patients were randomized into two groups: bone cement without antibiotic (No ATB, n  = 158) or cement with antibiotic (ATB, n  = 128), in which 2 g of vancomycin was added to 40 g of cement. The patients were followed up for 24 months after surgery.

Results  Regarding preoperative demographic data, the distribution of patients between groups was homogeneous ( p  < 0.05). In the 24-month period, the overall infection rate was of 2.09% (6/286), with no difference (odds ratio [OR] = 1.636; 95% confidence interval [CI]: 0.294–9.080; p  = 0.694) between the ATB group (1.56%; 2/128) and the No ATB group (2.53%; 4/158). In the No ATB group, the infection was caused by methicillin-resistant Staphylococcus aureus (MRSA) ( n  = 2), methicillin-sensitive S. aureus (MSSA) ( n  = 1) and Eschirichia coli ( n  = 1). Proteus mirabilis and MSSA were isolated from patients in the ATB group. Among the comorbidities, all patients with PAI were hypertensive and nondiabetic. Two rheumatoid arthritis patients who developed PAI were from the ATB group.

Conclusion  The use of cement with ATB reduced the absolute number of infections, but without statistical difference between the groups; thus, routine use should not be encouraged.

Evaluation of the costing methodology of published studies estimating costs of surgical site infections: A systematic review

OBJECTIVES

Surgical site infections (SSIs) are associated with increased length of hospitalization and costs. Epidemiologists and infection control practitioners, who are in charge of implementing infection control measures, have to assess the quality and relevance of the published SSI cost estimates before using them to support their decisions. In this review, we aimed to determine the distribution and trend of analytical methodologies used to estimate cost of SSIs, to evaluate the quality of costing methods and the transparency of cost estimates, and to assess whether researchers were more inclined to use transferable studies.

METHODS

We searched MEDLINE to identify published studies that estimated costs of SSIs from 2007 to March 2021, determined the analytical methodologies, and evaluated transferability of studies based on 2 evaluation axes. We compared the number of citations by transferability axes.

RESULTS

We included 70 studies in our review. Matching and regression analysis represented 83% of analytical methodologies used without change over time. Most studies adopted a hospital perspective, included inpatient costs, and excluded postdischarge costs (borne by patients, caregivers, and community health services). Few studies had high transferability. Studies with high transferability levels were more likely to be cited.

CONCLUSIONS

Most of the studies used methodologies that control for confounding factors to minimize bias. After the article by Fukuda et al, there was no significant improvement in the transferability of published studies; however, transferable studies became more likely to be cited, indicating increased awareness about fundamentals in costing methodologies.

A computerized indicator for surgical site infection (SSI) assessment after total hip or total knee replacement: The French ISO-ORTHO indicator

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Surgical site infection and costs in low- and middle-income countries: A systematic review of the economic burden

BACKGROUND

Surgical site infection (SSI) is a worldwide problem which has morbidity, mortality and financial consequences. The incidence rate of SSI is high in Low- and Middle-Income countries (LMICs) compared to high income countries, and the costly surgical complication can raise the potential risk of financial catastrophe.

OBJECTIVE

The aim of the study is to critically appraise studies on the cost of SSI in a range of LMIC studies and compare these estimates with a reference standard of high income European studies who have explored similar SSI costs.

METHODS

A systematic review was undertaken using searches of two electronic databases, EMBASE and MEDLINE In-Process & Other Non-Indexed Citations, up to February 2019. Study characteristics, comparator group, methods and results were extracted by using a standard template.

RESULTS

Studies from 15 LMIC and 16 European countries were identified and reviewed in full. The additional cost of SSI range (presented in 2017 international dollars) was similar in the LMIC ($174-$29,610) and European countries ($21-$34,000). Huge study design heterogeneity was encountered across the two settings.

DISCUSSION

SSIs were revealed to have a significant cost burden in both LMICs and High Income Countries in Europe. The magnitude of the costs depends on the SSI definition used, severity of SSI, patient population, choice of comparator, hospital setting, and cost items included. Differences in study design affected the comparability across studies. There is need for multicentre studies with standardized data collection methods to capture relevant costs and consequences of the infection across income settings.

Surgical site infection in elective clean and clean-contaminated surgeries in developing countries

BACKGROUND

Surgical site infection (SSI) is both the most frequently studied healthcare-associated infection and the most common healthcare-associated infection in the developing world. A systematic review and meta-analysis was conducted to evaluate the relative size of this burden and to estimate the prevalence of SSI in clean and clean-contaminated surgeries in a large sample of countries in the developing world.

METHODS

A systematic search of the MEDLINE/PubMed, Scopus, and LILACS databases was conducted to identify studies providing the prevalence of SSI in elective clean and clean-contaminated surgeries in 39 countries or regions around the world. Data of interest were limited to publications from January 2000 to December 2017. Studies with information on the number of cases of SSI and number of total elective clean and clean-contaminated surgeries during the same period were included in this evaluation. Studies lacking clear definition of the total number of exposed patients were excluded.

RESULTS

Based on the combined data from the 99 articles evaluated in this analysis, the overall prevalence of SSI in elective clean and clean-contaminated surgeries was estimated to be 6% (95% confidence interval (CI) 5-7%). This increased to 15% (95% CI 6-27%) when considering only those reports with post-discharge surveillance data. The overall prevalence of SSI in Africa/Middle East, Latin America, Asia, and China was 10% (95% CI 6-15%), 7% (95% CI 5-10%), 4% (95% CI 4-5%), and 4% (95% CI 2-6%), respectively. Significant variability in the data was confirmed by both the funnel plot and the Egger test (p=0.008).

CONCLUSIONS

Although the data are variable, it is clear that the incidence of SSI in the developing world is higher than that in the developed world.

PROTOCOL FOR TREATING ACUTE INFECTIONS IN CASES OF TOTAL KNEE ARTHROPLASTY

Objective:

To retrospectively evaluate the results after applying a protocol for treating acute infections in cases of total knee arthroplasty and to establish factors predictive of success or failure.

Methods:

Thirty-two patients who were diagnosed with acute infection of the knee following total arthroplasty between 2004 and 2009 were retrospectively evaluated. Infections following arthroplasty were treated in accordance with the protocol for acute infections following arthroscopy recommended at our institution.

Results:

With application of a treatment protocol for acute infections following total knee arthroplasty, 26 patients (81.2%) had good results and 6 (18.8%) had unsatisfactory results. Statistical analysis showed that the variables correlated with a worse prognosis were age (p = 0.038) and number of surgical debridement procedures performed (p = 0.038).

Conclusion:

Our treatment routine was effective for infection. Prosthesis revision was performed in 2 cases when the initial surgical debridement failed to control the infection. Nível de Evidência IV, Série de casos.

Economic burden of hospital malnutrition and the cost-benefit of supplemental parenteral nutrition in critically ill patients in Latin America

AIM

Disease-related malnutrition (DRM) is a prevalent condition that significantly increases the risk of adverse outcomes in hospitalized patients, particularly those with critical illness. Limited data is available on the economic burden of DRM and the cost-benefit of nutrition therapy in high-risk populations in Latin America. The aims of the present study were to estimate the economic burden of DRM and evaluate the cost-benefit of supplemental parenteral nutrition (SPN) in critically ill patients who fail to receive adequate nutrient intake from enteral nutrition (EN) in Latin America.

METHODS

Country-specific cost and prevalence data from eight Latin American countries and clinical data from studies evaluating outcomes in patients with DRM were used to estimate the costs associated with DRM in public hospitals. A deterministic decision model based on clinical outcomes from a randomized controlled study and country-specific cost data were developed to examine the cost-benefit of administering SPN to critically ill adults who fail to reach ≥60% of the calculated energy target with EN.

RESULTS

The estimated annual economic burden of DRM in public hospitals in Latin America is $10.19 billion (range, $8.44 billion-$11.72 billion). Critically ill patients account for a disproportionate share of the costs, with a 6.5-fold higher average cost per patient compared with those in the ward ($5488.35 vs. $839.76). Model-derived estimates for clinical outcomes and resource utilization showed that administration of SPN to critically ill patients who fail to receive the targeted energy delivery with EN would result in an annual cost reduction of $10.2 million compared with continued administration of EN alone.

LIMITATIONS

The cost calculation was limited to the average daily cost of stay and antibiotic use. The costs associated with other common complications of DRM, such as prolonged duration of mechanical ventilation or more frequent readmission, are unknown.

CONCLUSIONS

DRM imposes a substantial economic burden on Latin American countries, with critically ill patients accounting for a disproportionate share of costs. Cost-benefit analysis suggests that both improved clinical outcomes and significant cost savings can be achieved through the adoption of SPN as a therapeutic strategy in critically ill patients who fail to receive adequate nutrient intake from EN.

NEGATIVE-PRESSURE WOUND THERAPY IN THE TREATMENT OF COMPLEX INJURIES AFTER TOTAL KNEE ARTHROPLASTY

OBJECTIVE

To present an experience with negative-pressure wound therapy (NPWT) in the treatment of surgical wounds in patients treated for infections after total knee arthroplasty (TKA) with or without dehiscence and prophylaxis in wounds considered at risk of healing problems.

METHODS

We prospectively evaluated patients with TKA infection with or without surgical wound dehiscence and patients with risk factors for infection or surgical wound complications treated with Pico^(r) device for NPWT in addition to standard treatment of infection or dehiscence in our institution. We considered as an initial favorable outcome the resolution of the infectious process and the closure of the surgical wound dehiscences in the treated cases and the good progression of the wound without complicating events in the prophylactic cases.

RESULTS

We evaluated 10 patients who used Pico^(r) in our service. All patients had a favorable outcome according to established criteria. No complications were identified regarding the use of the NPWT device. The mean follow-up of the patients after the use of the device was 10.5 months.

CONCLUSION

The NPWT can be safely used in wound infections and complications following TKA with promising results. Long-term randomized prospective studies should be conducted to prove its effectiveness. Level of Evidence IV, Case Series.

[Incidence of hip and knee prosthetic infections in a specialized center of Mexico City]

BACKGROUND

Hip and knee prosthetic replacements have proven to be the most appropriate treatment in the joints that do not benefit from medical or arthroscopic interventions; however, infections are the most feared complication. It is recommended that the incidence of infection should not exceed 2%.

MATERIAL AND METHODS

This was an observational, prospective, longitudinal and observational study conducted in patients fitted with a prosthetic joint from August 2011 to July 2012. Patients were followed up pre and post-surgery for one year to identify a prosthetic infection, diagnosed using international parameters. We calculated the incidence of prosthetic infection, as well as the incidence density.

RESULTS

A total of 339 patients (179 hip and 160 knee) were included. Variations in the time of pre-operative antibiotics' administration were observed. Six prosthetic infections were identified with an incidence rate of 1.79/339 arthroplasties, 2.2/179 hip procedures, and 1.25/160 knee arthroplasties. An incidence density of 0.02/year for hip arthroplasties and 0.11/year for knee procedures was identified. There were 4 infections of hip and 2 of knee. Five infections were acute and one chronic. The isolated microorganisms were E. faecalis, S. epidermidis (2), S. mitis, S. aureus and P. stomatis.

CONCLUSIONS

The incidence of prosthetic joint infection in the first year of follow-up at our centre is within the recommended parameters. Surgical techniques and organizational practices influence the results.

Single vs Repeat Surgical Skin Preparations for Reducing Surgical Site Infection After Total Joint Arthroplasty: A Prospective, Randomized, Double-Blinded Study

BACKGROUND

Preventing surgical site infection (SSI) after total joint arthroplasty (TJA) is a high priority and is partly linked to the efficacy of surgical site preparation solutions (SPSs) in reducing the number of pathogens on the skin before incision. The aim of this study is to investigate the effectiveness of SRS reapplication after draping to reduce the incidence of SSI after TJA.

METHODS

Six hundred patients undergoing primary TJA between 2010 and 2011 at a single institution were recruited and randomly assigned to one of 2 groups. The patients in the intervention group (n = 300) received SPS that included alcohol and povidone-iodine before draping and an additional SPS by iodine povacrylex and isopropyl alcohol before application of the final adhesive drape, whereas the patients in the control group (n = 300) received a single SPS with alcohol and povidone-iodine before draping. Randomization was performed by an opaque envelope, and the rates of SSI and blistering were compared between groups.

RESULTS

Five seventy-seven patients completed the study and were included in the final analysis. There was a significant reduction in the incidence of superficial SSI for the intervention group (1.8%, 5 of 283) compared to the control group (6.5%, 19 of 294, P = .02). There were 2 (0.7%, 2 of 294) deep incisional SSIs in the control group, and 2 (0.7%, 2 of 283) organ-space SSIs in the intervention group (P = 1.00). In addition, skin blistering was lower in the intervention group (3.5%, 10 of 283) vs the control group (6.5%, 19 of 294), but this difference also did not reach statistical significance (P = .13).

CONCLUSION

Reapplication of an SPS after draping and before the application of iodophor-impregnated incisive draping resulted in a significant reduction in the rate of SSI in patients undergoing elective TJA.

Quality Assessment of Hospital Discharge Database for Routine Surveillance of Hip and Knee Arthroplasty–Related Infections

Objective.

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

Methods.

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

Results.

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

Conclusions.

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

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

Characterization of hip and knee arthroplasties and factors associated with infection

OBJECTIVE

To characterize arthroplasty procedures, calculate the surgical infection rate and identify related risk factors.

METHODS

This was a retrospective cohort study. Data on operations performed between 2010 and 2012 were gathered from documental sources and were analyzed with the aid of statistical software, using Fisher's exact test, Student's t test and the nonparametric Mann-Whitney and Wilcoxon tests.

RESULTS

421 total arthroplasty procedures performed on 346 patients were analyzed, of which 208 were on the knee and 213 on the hip. It was found that 18 patients (4.3%) were infected. Among these, 15 (83.33%) were reoperated and 2 (15.74%) died. The prevalence of infection in primary total hip arthroplasty procedures was 3%; in primary total knee arthroplasty, 6.14%; and in revision of total knee arthroplasty, 3.45%. Staphylococcus aureus was prevalent. The length of the surgical procedure showed a tendency toward being a risk factor (p = 0.067).

CONCLUSION

The prevalence of infection in cases of primary total knee arthroplasty was greater than in other cases. No statistically significant risk factors for infection were identified.

Burden of Surgical Site Infections Associated with Arthroplasty and the Contribution of Staphylococcus aureus

BACKGROUND

Patients undergoing arthroplasty are at considerable risk of experiencing post-operative complications, including surgical site infections (SSIs). In addition to potential economic consequences, SSIs can have a negative impact on patient outcomes and may potentially be life-threatening. Staphylococcus aureus has been consistently shown as the leading cause of SSIs associated with orthopedic surgery, with an important contribution from methicillin-resistant S. aureus (MRSA). This study evaluated the global burden of SSIs among patients undergoing orthopedic surgical procedures, and specifically those undergoing knee and hip arthroplasties.

METHODS

An extensive search of PubMed and recent conference proceedings was conducted. English articles published between 2003 and 2013 pertaining to SSI epidemiology, patient outcomes, and healthcare resource utilization and costs were reviewed.

RESULTS

Overall, 81 studies were included, mainly from North America and Europe. Median SSI and S. aureus SSI rates, calculated as percentage of all arthroplasty procedures, were 1.7% (range: 0.25%-4.4%; 15 studies) and 0.6% (range: 0.1%-23%), respectively. Median SSI rates were 1.3% (range: 0.05%-19%; 22 studies) after knee arthroplasty, and 2.1% (range: 0.05%-28%; 24 studies) after hip arthroplasty. S. aureus SSI rates ranged from 0.2%-2.4% and 0.18%-3.8% for patients undergoing knee and hip arthroplasty, respectively. The percentage of S. aureus SSIs because of MRSA varied widely within each patient category. SSI-related mortality data (14 studies) showed that in-hospital mortality rates were low (1.2%-2.5%), but increased with time after index arthroplasty procedure (up to 56% over 1 y). Studies assessing healthcare resource utilization (n = 21) revealed that developing post-orthopedic SSIs resulted in a two- to three-fold increase in length of hospital stay (LOS) compared with non-infected patients (median LOS: 18.9 d vs. 6 d for non-SSI patients). Patients with SSIs because of methicillin-resistant staphylococci incurred greater mean LOS compared with SSIs because of methicillin-sensitive organisms. Readmission rates reported in 11 studies indicate a greater likelihood in the presence of SSIs; comparison across studies was not feasible because of differences in data reporting. Consistent with increased healthcare resource utilization (LOS and readmission) associated with SSIs, cost studies (n = 23) revealed that the presence of SSIs was associated with up to three-fold cost increase compared with the absence of SSI across all orthopedic patient categories assessed.

CONCLUSIONS

SSIs are associated with increased morbidity, mortality rates, healthcare resource utilization, and costs. Despite the relatively low SSI incidence following orthopedic surgery and specifically arthroplasty, preventive methods, specifically those targeting S. aureus, would serve to minimize costs and improve patient outcomes.

Administration of Aspirin as a Prophylaxis Agent Against Venous Thromboembolism Results in Lower Incidence of Periprosthetic Joint Infection

The efficacy and safety of aspirin (ASA) for prevention of venous thromboembolism (VTE) following total joint arthroplasty (TJA) have been demonstrated. Our hypothesis was that postoperative ASA compared to warfarin lowers the incidence of periprosthetic joint infection (PJI). Between January 2006 and December 2012, 1456 patients received ASA and 1700 patients received warfarin following primary TJA as standard VTE prophylaxis. Logistic regression was utilized to identify independent risk factors of PJI. Incidence of PJI was significantly lower at 0.4% in patients receiving ASA vs. 1.5% in patients receiving warfarin (P<0.001). Warfarin and elevated BMI were independent risk factors for PJI following TJA (P<0.05). Our research suggests that the use of ASA compared to warfarin for VTE prophylaxis reduces the risk of PJI following TJA.

Economical analysis on prophylaxis, diagnosis, and treatment of periprosthetic infections

The economic burden of periprosthetic infections is enormous, but the number of economic studies dealing with this issue is very scarce. This review tries to know the economic literature existing, assess the value of current data, and recognize the less costly and more effective procedures for prevention, diagnosis and treatment of periprosthetic infections. Forty five studies meeting the inclusion criteria and adhering to the quality criteria used were carefully analyzed to extract the economic data of relevance in evaluating the magnitude of problem and the more cost-effective solutions. However, because the heterogeneity and the low-quality of most of these studies meta-analytical technique has not been possible. Instead, the studies have been reviewed descriptively. Optimizing the antibiotic use in the prevention and treatment of periprosthetic infection, combined with systemic and behavioral changes in the operating room; detecting and treating the high-risk groups; a quick, simple, reliable, safe, and cost-effective diagnosis, and the rationale management of the instituted infection, specifically using the different procedures according to each particular case, could allow to improve outcomes and produce the highest quality of life for patients and the lowest economic impact. Nevertheless, the cost effectiveness of different interventions to prevent and to treat the periprosthetic infection remains unclear.

Treatment of periprosthetic infections: an economic analysis

This review summarizes the existing economic literature, assesses the value of current data, and presents procedures that are the less costly and more effective options for the treatment of periprosthetic infections of knee and hip. Optimizing antibiotic use in the prevention and treatment of periprosthetic infection, combined with systemic and behavioral changes in the operating room, the detection and treatment of high-risk patient groups, as well as the rational management of the existing infection by using the different procedures according to each particular case, could allow for improved outcomes and lead to the highest quality of life for patients and the lowest economic impact. Nevertheless, the costeffectiveness of different interventions to treat periprosthetic infections remains unclear.