Antimicrobial Prophylaxis for the Prevention of Surgical Site Infections in Orthopaedic Oncology - A Narrative Review of Current Concepts

Development and validation of a nomogram to predict surgical site infection after soft-tissue sarcoma resection

Aims

Surgical site infection (SSI) after soft-tissue sarcoma (STS) resection is a serious complication. The purpose of this retrospective study was to investigate the risk factors for SSI after STS resection, and to develop a nomogram that allows patient-specific risk assessment.

Methods

A total of 547 patients with STS who underwent tumour resection between 2005 and 2021 were divided into a development cohort and a validation cohort. In the development cohort of 402 patients, the least absolute shrinkage and selection operator (LASSO) regression model was used to screen possible risk factors of SSI. To select risk factors and construct the prediction nomogram, multivariate logistic regression was used. The predictive power of the nomogram was evaluated by receiver operating curve (ROC) analysis in the validation cohort of 145 patients.

Results

LASSO regression analysis selected possible risk factors for SSI, including age, diabetes, operating time, skin graft or flap, resected tumour size, smoking, and radiation therapy. Multivariate analysis revealed that age, diabetes, smoking during the previous year, operating time, and radiation therapy were independent risk factors for SSI. A nomogram was developed based on the results of multivariate logistic regression analysis. In the development cohort, the incidence of SSI was 4.5% in the low-risk group (risk score < 6.89) and 26.6% in the high-risk group (risk score ≥ 6.89; p < 0.001). In the validation cohort, the incidence of SSI was 2.0% in the low-risk group and 15.9% in the high-risk group (p = 0.004).

Conclusion

Our nomogram will enable surgeons to assess the risk of SSI in patients with STS. In patients with high risk of SSI, frequent monitoring and aggressive interventions should be considered to prevent this.

Topical Application of Vancomycin Powder to Prevent Infections after Massive Bone Resection and the implantation of Megaprostheses in Orthopaedic Oncology Surgery

Introduction

Periprosthetic joint infection (PJI) represents a serious burden in orthopaedic oncology. Through the years, several local expedients have been proposed to minimise the risk of periprosthetic infection. In this study, we report our outcomes using topical vancomycin powder (VP) with the aim to prevent PJIs.

Materials and methods

Fifty oncological cases treated with massive bone resection and the implant of a megaprosthesis were included in our study. Among them, 22 [(GGroup A) received one gram of vancomycin powder on the surface of the implant and another gram on the surface of the muscular fascia]. The remaining 28 did not receive such a treatment (Group B). The rest of surgical procedures and the follow-up were the same for the two groups. Patients underwent periodical outpatient visits, radiographs and blood exams' evaluations. Diagnosis of PJIs and adverse reactions to topical vancomycin were recorded.

Results

None of the cases treated with topical vancomycin developed infections, whereas 6 of the 28 cases (21.4%) who did not receive the powder suffered from PJIs. These outcomes suggest that cases treated with VP had a significantly lower risk of post-operative PJI (p=0.028). None of our cases developed acute kidney failures or any other complication directly or indirectly attributable to the local administration of VP.

Conclusions

The topical use of vancomycin powder on megaprosthetic surfaces and the overlying fascias, alongside with a correct endovenous antibiotic prophylaxis, can represent a promising approach in order to minimise the risk of periprosthetic infections in orthopaedic oncology surgery.

Broad-spectrum antibiotic prophylaxis in tumor and infected orthopedic surgery-the prospective-randomized, microbiologist-blinded, stratified, superiority trials: BAPTIST Trials

BACKGROUND

The perioperative antibiotic prophylaxis with 1st or 2nd generation cephalosporins is evidence-based in orthopedic surgery. There are, however, situations with a high risk of prophylaxis-resistant surgical site infections (SSI).

METHODS

We perform a superiority randomized controlled trial with a 10% margin and a power of 90% in favor of the broad-spectrum prophylaxis. We will randomize orthopedic interventions with a high risk for SSI due to selection of resistant pathogens (open fractures, surgery under therapeutic antibiotics, orthopedic tumor surgery, spine surgery with American Society of Anesthesiologists (ASA) score ≥ 3 points) in a prospective-alternating scheme (1:1, standard prophylaxis with cefuroxime versus a broad-spectrum prophylaxis of a combined single-shot of vancomycin 1 g and gentamicin 5 mg/kg parenterally). The primary outcome is "remission" at 6 weeks for most orthopedic surgeries or at 1 year for surgeries with implant. Secondary outcomes are the risk for prophylaxis-resistant SSI pathogens, revision surgery for any reason, change of antibiotic therapy during the treatment of infection, adverse events, and the postoperative healthcare-associated infections other than SSI within 6 weeks (e.g., urine infections or pneumonia). With event-free surgeries to 95% in the broad-spectrum versus 85% in the standard prophylaxis arm, we need 2 × 207 orthopedic surgeries.

DISCUSSION

In selected patients with a high risk for infections due to selection of prophylaxis-resistant SSI, a broad-spectrum combination with vancomycin and gentamycin might prevent SSIs (and other postoperative infections) better than the prophylaxis with cefuroxime.

TRIAL REGISTRATION

ClinicalTrial.gov NCT05502380. Registered on 12 August 2022. Protocol version: 2 (3 June 2022).

Operative Treatment and Outcomes of Pediatric Patients with an Extremity Bone Tumor: A Secondary Analysis of the PARITY Trial Data

BACKGROUND

Osteosarcoma and Ewing sarcoma are the 2 most common primary bone sarcomas, occurring predominantly in pediatric patients, with the incidence of osteosarcoma correlating with periods of peak bone-growth velocity. Although survival outcomes have plateaued over the past several decades, ongoing treatment advances have improved function, decreased infection rates, and improved other clinical outcomes in patients with bone tumors. Recently, the Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial addressed the serious problem of surgical site infection (SSI) and the lack of consensus regarding the appropriate prophylactic postoperative antibiotic regimen. The objective of the present secondary analysis of the PARITY trial was to characterize the modern treatment and surgical and oncologic outcomes of pediatric patients with bone tumors at 1 year postoperatively.

METHODS

The PARITY trial included patients ≥12 years old with a bone tumor or soft-tissue sarcoma that was invading the femur or tibia, necessitating osseous resection and endoprosthetic reconstruction. This pediatric subanalysis of the PARITY trial data included all PARITY patients ≤18 years old. As in the main PARITY study, patients were randomized to either a 5-day or 1-day course of postoperative antibiotic prophylaxis. The primary outcome measure was the development of an SSI within 1 year, and secondary outcomes included antibiotic-related adverse events, unplanned additional operations, local recurrence, metastasis, and death.

RESULTS

A total of 151 patients were included. An adjudicated SSI occurred in 27 patients (17.9%). There was no difference in the rate of any SSI between the 5-day and 1-day antibiotic groups (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.4 to 1.9; p = 0.82). Antibiotic-related complications occurred in 13 patients (8.6%), with no difference noted between groups (HR, 0.46; 95% CI, 0.2 to 1.4; p = 0.18). A total of 45 patients (29.8%) required a return to the operating room within the first postoperative year, which corresponded with a 68.8% reoperation-free rate of survival at 1 year when accounting for competing risks. The most common reason for reoperation was infection (29 of 45; 64.4%). A total of 7 patients (4.6%) required subsequent amputation of the operative extremity, and an additional 6 patients (4.0%) required implant revision within 12 months. A total of 36 patients (23.8%) developed metastases, and 6 patients (4.0%) developed a local recurrence during the first postoperative year. A total of 11 patients (7.3%) died during the study period. There were no significant differences in oncologic outcomes between the 5-day and 1-day antibiotic groups (HR, 0.97; 95% CI, 0.5-1.8; p = 0.92).

CONCLUSIONS

There were no significant differences in surgical or oncologic outcomes between pediatric patients who underwent a 1-day versus 5-day antibiotic regimen following endoprosthetic reconstruction in the PARITY trial. Surgeons should be aware of and counsel patients and caregivers regarding the 30% rate of reoperation and the risks of infection (17.9%), death (7.3%), amputation (4.6%), and implant revision (4%) within the first postoperative year.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Surgical Site Infections in Elective Orthopedic Foot and Ankle Surgery: The Role of Diabetes Mellitus

Surgical site infection (SSI) after elective orthopedic foot and ankle surgery is uncommon and may be higher in selected patient groups. Our main aim was to investigate the risk factors for SSI in elective orthopedic foot surgery and the microbiological results of SSI in diabetic and non-diabetic patients, in a tertiary foot center between 2014 and 2022. Overall, 6138 elective surgeries were performed with an SSI risk of 1.88%. The main independent associations with SSI in a multivariate logistic regression analysis were an ASA score of 3-4 points, odds ratio (OR) 1.87 (95% confidence interval (CI) 1.20-2.90), internal, OR 2.33 (95% CI 1.56-3.49), and external material, OR 3.08 (95% CI 1.56-6.07), and more than two previous surgeries, OR 2.86 (95% CI 1.93-4.22). Diabetes mellitus showed an increased risk in the univariate analysis, OR 3.94 (95% CI 2.59-5.99), and in the group comparisons (three-fold risk). In the subgroup of diabetic foot patients, a pre-existing diabetic foot ulcer increased the risk for SSI, OR 2.99 (95% CI 1.21-7.41), compared to non-ulcered diabetic patients. In general, gram-positive cocci were the predominant pathogens in SSI. In contrast, polymicrobial infections with gram-negative bacilli were more common in contaminated foot surgeries. In the latter group, the perioperative antibiotic prophylaxis by second-generation cephalosporins did not cover 31% of future SSI pathogens. Additionally, selected groups of patients revealed differences in the microbiology of the SSI. Prospective studies are required to determine the importance of these findings for optimal perioperative antibiotic prophylactic measures.

[Fatal necrotizing fasciitis with clostridium perfringens infection following resection of soft tissue sarcoma of the thigh]

We present the case of a 57-year-old male patient with a fatal outcome after resection of a soft tissue sarcoma of the lateral thigh. A polymicrobial surgical site infection with Staphylococcus lugdunensis and Clostridium perfringens caused fulminant necrotising fasciitis with an additional gas gangrene. The patient suffered a severe sepsis with consecutive haemolysis and multiorgan failure. The authors recapitulate the deadly progress of a rarely reported complication after oncological resection. The therapeutic approach and surgical interventions are discussed based on the current literature.

Cutaneous diphtheria complicated oncologic reconstruction surgery in osteosarcoma

Diphtheria is an uncommon bacterial infection of the upper respiratory tract. We described a surgical site infection in a young adolescent female on maintenance chemotherapy. Corynebacterium diphtheriae was recovered from the wound, and she was treated with antibiotics and antitoxin. Cutaneous diphtheria should be considered in immunocompromised patients receiving chemotherapy.

A Short-Course Antibiotic Prophylaxis Is Associated with Limited Antibiotic Resistance Emergence in Post-Operative Infection of Pelvic Primary Bone Tumor Resection

Resections of primary pelvic bone tumors are frequently complicated by surgical site infections (SSIs), thereby impairing the functional prognosis of patients, especially in case of implant removal. Although prophylactic antibiotics play an essential role in preventing SSIs, there are presently no recommendations that support their appropriate use. This study aimed to assess the impact of a 24 h prophylactic protocol on the bacterial ecology, the resistance pattern, and the SSI healing rate. We hypothesized that this protocol not only limits the emergence of resistance but also results in a good cure rate with implant retention in case of SSI. A retrospective study was performed that included all patients with an SSI following a pelvic bone tumoral resection between 2005 and 2017 who received a 24 h antibiotic prophylaxis protocol. Twenty-nine patients with an SSI were included. We observed a 75.9% rate of polymicrobial infection, with a high prevalence of digestive flora microorganisms and a majority of wild-type phenotypes. We confirmed that there was no significant emergence of resistant flora. After first-line debridement, antibiotics (DA) if any implant was used, or debridement, antibiotics, and implant retention (DAIR) whenever possible, we obtained a 79.3% cure rate, with implant removal in 20% of cases. The absence of an implant was significantly associated with SSI healing. Early infection management and low resistance profiles may also have a positive effect, but this needs to be confirmed in a larger cohort. In light of this, the use of a 24 h prophylactic protocol in primary pelvic bone tumor resections is associated with a favorable infection cure rate and implant retention in case of SSI, and minimal selection of resistant microorganisms.

Deep surgical site infections following double-dose perioperative antibiotic prophylaxis in adult obese orthopedic patients

BACKGROUND

Obesity is a risk factor for surgical site infections (SSI). Based on retrospective comparisons and pharmacology, many orthopedic centers have adopted weight- or body mass index (BMI)-related antibiotic prophylaxis.

METHODS

Double-dose prophylaxis was introduced in March 2017 for patients weighting >80 kg. The period April 2014 to March 2017 ('before') was compared to the period March 2017 to June 2019 ('after') regarding the impact on deep SSIs.

RESULTS

A total of 9318 surgeries 'before' were compared to 7455 interventions 'after' the introduction of double-dose prophylaxis. Baseline demographic characteristics (age, sex, BMI, American Society of Anesthesiologists score, and duration of surgery) were similar. In the period 'after', 3088 cases (3088/16 773; 18%) received double-dose prophylaxis. Overall, 82 deep SSIs were observed (0.5%). The pathogens were resistant to the standard cefuroxime prophylaxis in 30 cases (30/82; 37%). Excluding these prophylaxis-resistant cases and all of the five hematogenous SSIs, the remaining 47 SSIs (57%) could have been prevented by the preceding prophylaxis. Double-dosing of parenteral cefuroxime from 1.5 g to 3.0 g in obese patients did not reduce deep SSIs (hazard ratio 0.7, 95% confidence interval 0.3-1.6). In the direct group comparison among obese patients >80 kg, the double-dose prophylaxis equally failed to alter the SSI risk (3088/16 726 non-infections vs 8/47 SSI despite double-dose prophylaxis; Chi-square test, P = 0.78).

CONCLUSIONS

In this single-center before-and-after study with almost 17 000 orthopedic surgeries in adult patients, systemic doubling of the perioperative antibiotic prophylaxis in obese patients clinically failed to reduce the overall deep SSI risk.

Antibacterial hydrogel coating in joint mega-prosthesis: results of a comparative series

PURPOSE

Joint mega-prosthesis after bone tumors, severe trauma or infection is associated with high rates of post-surgical septic complications. A fast-resorbable antibacterial hydrogel coating (DAC®, Defensive Antibacterial Coating) has previously been shown to be able to significantly reduce surgical site infection in various clinical settings. Aim of the present study was to evaluate the safety and efficacy of the DAC hydrogel coating to prevent early periprosthetic joint infection after joint mega-prosthesis.

METHODS

In this three-centers, case-control study, 43 patients, treated with an antibacterial hydrogel coated mega-prosthesis for oncological (N = 39) or non-oncological conditions (N = 4), were retrospectively compared with 43 matched controls, treated with mega-implants without the coating. Clinical, laboratory and radiographic examinations were performed to evaluate the occurrence of post-surgical infection, complications and adverse events.

RESULTS

At a mean follow-up of 2 years, no evidence of infection or adverse events were observed in the DAC-treated group, compared to six cases of post-surgical infection in the control group.

CONCLUSION

This matched case-control study shows that a fast-resorbable, antibiotic-loaded coating can be safely used to protect joint mega-prosthesis, providing a reduction of early surgical site infections with no side effects. Larger prospective trials with longer follow-ups are warranted to confirm this report.

TRIAL REGISTRATION

RS1229/19 (Regina Elena National Cancer Institute Experimental Registry Number).

Antibiotic prophylaxis for prevention of wound infections after soft tissue sarcoma resection: A retrospective cohort study

BACKGROUND AND OBJECTIVES

The use of antibiotic prophylaxis for soft tissue sarcoma resection varies widely while little evidence on this topic exists. The aim of this study was to determine the impact of antibiotic prophylaxis on the occurrence of wound infections.

METHODS

A single institutional retrospective cohort study was performed on patients who underwent truncal or extremity soft tissue sarcoma resection. The use of antibiotic prophylaxis was assessed and univariate and multivariate analysis of predictors of wound infections was performed.

RESULTS

Nine hundred and fifty-eight patients could be included. Thirty-two percent of patients had no antibiotic prophylaxis, 44% of patients received single-shot prophylaxis, and 24% of patients received single-shot plus continued antibiotic treatment. Wound infections occurred in 140 patients (15%). Independent risk factors for wound infections upon multivariate analysis were obesity, high American Society of Anesthesiologists (ASA) status, high tumor size and grade, operation time over 120 minutes, and other complications. Antibiotic prophylaxis could not be identified as a protective factor in univariate or multivariate analysis.

CONCLUSIONS

A favorable effect of antibiotic prophylaxis on the occurrence of wound infections could not be observed. Although more studies on this subject are needed, our data do not support the general use of antibiotic prophylaxis for soft tissue sarcoma resection.