Gentamicin-Impregnated Collagen Sponge: Effectiveness in Preventing Sternal Wound Infection in High-Risk Cardiac Surgery

Antibiotic Prophylaxis and Treatment for Cardiac Device Infections

Cardiac device infections (CDIs) are a serious complication in patients with implanted devices, resulting in increased morbidity, prolonged hospital stay, and increased healthcare costs. The effective management of these infections involves a combination of appropriate antibiotic therapy and preventive strategies aimed at reducing the risk of infection. The role of antibiotic prophylaxis in infection prevention is crucial, including the emerging use of antibiotic-supported tools and other local antibiotic delivery systems, which may reduce the risk of infection at the device implant site. In this contemporary review, we provide an overview of the prophylactic treatment and different antibiotic regimens for the treatment of CDIs, emphasizing early diagnosis, appropriate choice of antibiotics, and individualized treatment.

Prevention and Risk Assessment of Cardiac Device Infections in Clinical Practice

The implantation of cardiac electronic devices (CIEDs), including pacemakers and defibrillators, has become increasingly prevalent in recent years and has been accompanied by a significant rise in cardiac device infections (CDIs), which pose a substantial clinical and economic burden. CDIs are associated with hospitalizations and prolonged antibiotic therapy and often necessitate device removal, leading to increased morbidity, mortality, and healthcare costs worldwide. Approximately 1-2% of CIED implants are associated with infections, making this a critical issue to address. In this contemporary review, we discuss the burden of CDIs with their risk factors, healthcare costs, prevention strategies, and clinical management.

Reconstruction of Orbital Wall Fractures with a Combination of Resorbable Plates and Antibiotic-Impregnated Collagen Sheets

(1) Background: Orbital wall fractures are common in maxillofacial trauma, and artificial implants are often used for reconstruction. However, there has always been concern about infection because implants are directly exposed to the airway. This study was conducted to determine the effectiveness of a combination of resorbable plates and antibiotic-impregnated collagen sheets in reconstructions of orbital fractures and to determine whether it had an effect in reducing postoperative antibiotic use. (2) Methods: The retrospective study was conducted on 195 patients who underwent orbital wall reconstruction from March 2019 to August 2022. The 176 patients in the control group underwent reconstruction using only resorbable plates and were administered postoperative antibiotics for 5 to 7 days. On the other hand, the 19 patients in the experimental group underwent reconstruction using a combination of resorbable plates and antibiotic-impregnated collagen sheets and only received antibiotics once before surgery. The occurrence of ocular complications, the length of hospitalization, the infection incidence rate, and the adverse effects of antibiotics were investigated. (3) Results: significant ocular complications were observed in the experimental group during a follow-up period of more than 1 year. Regarding postoperative infections, there were two cases of infection in the control group (infection rate: 1.14%), while no infection was found in the experimental group. The hospitalization period of the experimental group was significantly shorter than that of the control group (p < 0.01), and the incidence of total adverse effects of antibiotics, especially nausea, was lower in the experimental group (p = 0.02). (4) Conclusions: The combined use of resorbable plates and antibiotic-impregnated collagen sheets allows effective orbital wall reconstruction without infection, with a shorter hospital stay, and with fewer antibiotic adverse effects.

Surgical Site Infection in Cardiac Surgery

Surgical site infections (SSIs) are one of the most significant complications in surgical patients and are strongly associated with poorer prognosis. Due to their aggressive character, cardiac surgical procedures carry a particular high risk of postoperative infection, with infection incidence rates ranging from a reported 3.5% and 26.8% in cardiac surgery patients. Given the specific nature of cardiac surgical procedures, sternal wound and graft harvesting site infections are the most common SSIs. Undoubtedly, DSWIs, including mediastinitis, in cardiac surgery patients remain a significant clinical problem as they are associated with increased hospital stay, substantial medical costs and high mortality, ranging from 3% to 20%. In SSI prevention, it is important to implement procedures reducing preoperative risk factors, such as: obesity, hypoalbuminemia, abnormal glucose levels, smoking and S. aureus carriage. For decolonisation of S. aureus carriers prior to cardiac surgery, it is recommended to administer nasal mupirocin, together with baths using chlorhexidine-based agents. Perioperative management also involves antibiotic prophylaxis, surgical site preparation, topical antibiotic administration and the maintenance of normal glucose levels. SSI treatment involves surgical intervention, NPWT application and antibiotic therapy.

A Preliminary Exploration of the Efficacy of Gentamicin Sponges in the Prevention and Treatment of Wound Infections

Purpose

This study aimed to construct drug-loading and drug-releasing quantitative equations for gentamicin sponges in addition to realizing a gentamicin sponge for wound infection prevention and treatment.

Methods

Sterile sponges were cut into pieces of 1×1 × 0.5 cm and immersed in 40, 16, 8, 4, 1.6, 0.8, or 0 mg/mL of gentamicin solution for 12, 24, 48, 96, or 120 h to evaluate their gentamicin loading. The sponges were subsequently immersed in the gentamicin solution of different concentrations for 48 h, air-dried, and then immersed in 10 mL of 0.9% physiological saline to evaluate the gentamicin release. Methicillin-sensitive Staphylococcus aureus (MSSA) and Pseudomonas aeruginosa were used to explore the sponges’ infection prevention scheme. In addition, a rat femur fracture with wound infection model was used to assess the infection treatment scheme.

Results

The antibacterial zone sizes of the sponges immersed in 40, 16, 8, 4, 1.6, and 0.8 mg/mL of the gentamicin solution were larger than those of the 0 mg/mL air-dried sponge, and the difference was statistically significant (p < 0.01, p < 0.01, p < 0.01, p < 0.01, p < 0.01, and p < 0.01, respectively). The rats in the 40, 16, and 8 mg/mL air-dried sponge groups had no wound suppuration in either the MSSA or P. aeruginosa rat infection models.

Conclusion

A quantified equation for the sponges’ gentamicin loading and release was achieved with high accuracy. Furthermore, we recommend the 40, 16, or 8 mg/mL air-dried sponge for the treatment of wounds with antibiotic-sensitive bacterial infections.

Locally Used Antibiotics for Spinal Infection Prophylaxis and Their Effects on Epidural Fibrosis: an Experimental Laminectomy Study in Rats Using Rifamycin and Gentamycin

The study aims to assess the effects of antibiotics (ABs), which are typically used in spinal infection prophylaxis, on the formation of epidural fibrosis (EF). Specifically, we investigated the effect of rifamycin and gentamycin on EF formation in laminectomized rats. Thirty-two rats were randomly and equally divided into four groups as follows: laminectomy and physiological saline (0.9% NaCl) solution (control); laminectomy and rifamycin; laminectomy and gentamicin; and laminectomy and a mixture of rifamycin and gentamicin. Laminectomy was performed on L1 and L2 vertebrae in all rats. One month after spinal surgery, spinal tissue samples surrounding the laminectomy were cut with a microtome and stained with hematoxylin-eosin and Masson's trichrome. The histopathological analysis included examining the extent of EF, fibroblast cell density, and cartilage and bone regeneration. Statistical analysis was performed using the IBM SPSS Statistics 22 program (SPSS IBM, Turkey). A value of p < 0.05 was considered statistically significant. EF value differences between the AB treatment groups and the control group were statistically significant (p = 0.030). Specifically, binary comparisons indicated that the EF value was significantly higher in the rifamycin group than that in the control group (p = 0.003; p < 0.05). Our study suggests that locally applied ABs, especially rifamycin, should be diluted before administration to the epidural space.

In vitro Antimicrobial Activity of Chlorquinaldol against Microorganisms Responsible for Skin and Soft Tissue Infections: Comparative Evaluation with Gentamicin and Fusidic Acid

Skin and soft tissue infections (SSTIs) are a major therapeutic challenge for clinicians. The emergence of pathogens with decreased susceptibility to available therapies has become an emerging problem often associated with treatment failure. Hence, there is an urgent need for novel broad-spectrum antimicrobial agents. The purpose of this study was to assess the feasibility of chlorquinaldol as an alternative approach to currently used topical antibiotics for the treatment of skin and soft tissue infections. The activity of chlorquinaldol was investigated against a collection of bacterial isolates responsible for skin infections, including strains resistant to fusidic acid and gentamicin. After determination of MIC and MBC, time-kill experiments were carried out by counting colonies grown after 0, 3, 6, 9, 24, and 48 h of incubation with concentrations equal to ¼×, ½×, 1×, 2×, and 4× MIC of chlorquinaldol, gentamicin, or fusidic acid. Staphylococci resulted the Gram-positives most sensitive to chlorquinaldol, with MIC-values ranging from 0.016 to 0.5 mg/L. A lower activity was observed against Gram-negative bacteria, with 77% of the isolates being inhibited at concentrations ranging from 128 to 512 mg/L. Generally, in time-kill studies, chlorquinaldol showed a bactericidal activity at the higher concentrations (2×, 4× MIC) after 24-48 h of incubation. In conclusion, chlorquinaldol may represent a valuable alternative to conventional topical antibiotics for the treatment of skin and soft tissue infections.