Vancomycin Solution Research Articles

Carbon-carbon composite material as a potential basis for orthopedic implants

Aim. To determine the cytocompatibility of carbon-carbon composite materials (CCCM) and assess their ability to be impregnated with vancomycin.Materials and Methods. The study included samples of carbon-carbon composite materials (CCCM). The cytocompatibility of CCCM blocks was evaluated using a culture of eukaryotic cells (Vero cell line). Biofilms of S. aureus ATCC 29213 (MSSA), S. aureus ATCC 43300 (MRSA), S. epidermidis ATCC 12228 (MSSE), and S. epidermidis ATCC 29887 (MRSE) were formed by immersing sterile test samples of CCCM into a nutrient medium which contained bacteria. After 24-hour incubation, the samples were washed, placed in an ultrasonic bath, and sonication fluid was inoculated using the sector method. To saturate the CCCM blocks with antibiotics, they were placed into a vancomycin solution and then lyophilized under negative pressure with gradual heating. The antimicrobial activity of the resulting blocks was studied using the cup plate method against the same reference cultures of staphylococci. The dynamics of vancomycin elution from CCCM was investigated using high-performance liquid chromatography.Results. Vero cells maintained their viability in the presence of the tested material. Considering the highly porous structure of CCCM and variable diameter of the pores, we suggested a good osteointegration potential of this material. On the samples without an impregnation with an antibacterial drug, reference strains of staphylococci were able to form a biofilm with a sufficient number of bacterial cells to initiate an infectious process. The duration of antimicrobial activity of the antibioticim-pregnated samples against the reference staphylococcal strains was up to 3 days. The majority of the antibiotic eluted from the CCCM into the incubation medium during the first two days.Conclusion. The cytocompatibility and porosity of CCCM in combination with a vancomycin impregnation makes this material promising for the fabrication of implants with antimicrobial activity as well as tissue engineering constructs.

Evaluation of the Impact of Infusion Set Design on the Particulate Load Induced by Vancomycin-Piperacillin/Tazobactam Incompatibility.

Drug incompatibilities are among the most common medication errors in intensive care units. A precipitate can form and block the catheter or cause an adverse event in the patient. Intensive care units have implemented various strategies for limiting the occurrence of these incompatibilities, which have already been studied in vitro under standardized conditions. The objective of the present in vitro study was to continue these assessments by determining the impact of the infusion line geometry and the drugs' position in the infusion set-up on the prevention of vancomycin-piperacillin/tazobactam incompatibility. Infusion lines with a different common volume, a multilumen medical infusion device, a dilute vancomycin solution, and separate infusions of incompatible drugs were evaluated separately. The infusion line outlet was connected to a dynamic particle counter. Reducing the common volume, using multilumen medical devices, or spacing out the two incompatible drugs on the infusion line did not prevent the occurrence of a significant particulate load. Only dilution of the vancomycin solution was associated with a significantly lower particulate load and the absence of drug incompatibility. Our results show that under specific conditions, it is possible to reduce particulate contamination considerably.

Poster 349: Tobramycin-Soaked Grafts for the Prevention of Infection Following Anterior Cruciate Ligament Reconstruction: A Retrospective Review of Infection Rate

Objectives: Infection can be a devastating complication of anterior cruciate ligament (ACL) reconstruction. Soaking or wrapping grafts in vancomycin solution has been adopted by many surgeons to prevent infection following ACL reconstruction. Recent meta-analysis demonstrated a significant reduction in the incidence of deep infection in vancomycin-soaked grafts to be 0.09% compared to 0.74% for nontreated grafts.1 Tobramycin may provide an alternative for patients with vancomycin allergies or if vancomycin is not available. The purpose of this study is to evaluate the incidence of deep and superficial infection following ACL reconstruction in young patients with tobramycin-soaked grafts as well as characterize potential risk factors for infection. We hypothesize that tobramycin-soaked grafts result in a low deep infection rate, comparable to that of vancomycin-soaked grafts published in the literature. Methods: A total of 812 consecutive patients under age 20 who underwent ACL reconstruction at an academic medical center between 2010 and 2020 with tobramycin-soaked grafts were identified. Retrospective chart review was performed to identify postsurgical superficial and deep wound infections, as well as other pertinent surgical characteristics. The incidence of infection in this tobramycin wrap cohort was compared to the incidence of infection of vancomycin wraps as published in the literature. Results: Superficial wound infections occurred in 24 patients (2.96%) and 0 deep joint infections were identified in the tobramycin wrap cohort. The incidence of infection was 3.16% in 728 patients who received prophylactic perioperative intravenous Cefazolin and 1.23% infection incidence in 81 patients who received prophylactic perioperative Clindamycin (p = 0.30). In addition, no significant difference in incidence of superficial infection was found with patient age, sex, body mass index, or graft type. Conclusions: Tobramycin-soaked ACL grafts demonstrate a low infection risk comparable to that of vancomycin-soaked ACL grafts. The type of prophylactic IV antibiotic used in this young cohort did not impact the incidence of superficial wound infection. Further work with larger and older cohorts is needed to better characterize risk factors for postoperative infection following ACL reconstruction for all ages and comorbidities.

Presoaking Grafts in Vancomycin Does Not Impair Graft-Bone Healing in a Rat Anterior Cruciate Ligament Reconstruction Model

Background: The vancomycin presoaking technique (wherein grafts are treated with a vancomycin solution [VS] for anterior cruciate ligament reconstruction [ACLR]) reduces the infection rate after ACLR. However, the effects of this technique on graft-bone healing have not been fully elucidated. Purpose: To investigate the effects of vancomycin presoaking on graft-bone healing in a rat ACLR model. Study Design: Controlled laboratory study. Methods: Long flexor digitorum longus tendons were obtained from 9 Wistar rats, and each was randomly allocated to the normal saline (NS) or VS groups. The grafts were immersed in sterile saline for 30 minutes in the NS group and in a 5-mg/mL VS in the VS group. The presence of time-zero graft bacterial contamination was confirmed, and the grafts were incubated in Fluidised Thioglycollate Broth for 2 weeks. ACLR was performed on the right knees of 65 male Wistar rats using the flexor digitorum longus tendons. Each graft was similarly treated. Biomechanical testing, micro–computed tomography, and histological evaluations were performed 4 and 12 weeks postoperatively. Results: The VS group showed significantly reduced graft contamination at time zero (P = .02). The mean maximum loads to failure were 13.7 ± 8.2 N and 11.6 ± 4.8 N in the NS and VS groups, respectively, at 4 weeks (P = .95); and 23.2 ± 13.2 N and 30.4 ± 18.0 N in the NS and VS groups, respectively, at 12 weeks (P = .35). Regarding micro–computed tomography, the mean bone tunnel volumes were 3.76 ± 0.48 mm3 and 4.40 ± 0.58 mm3 in the NS and VS groups, respectively, at 4 weeks (P = .41); and 3.51 ± 0.38 mm3 and 3.67 ± 0.35 mm3 in the NS and VS groups, respectively, at 12 weeks (P = .54). Histological semiquantitative examination revealed no clear between-group differences at any time point. Conclusion: Presoaking grafts in vancomycin in a rat ACLR model demonstrated no discernible adverse effects on short- and midterm biomechanical, radiological, and histological investigations. Clinical Relevance: The findings provide guidance for surgeons when considering this technique.

Optimization of therapeutic drug monitoring of vancomycin in newborns using “Dried Blood Spot” method

Therapeutic drug monitoring (TDM) is used to increase the individualization of pharmacotherapy, especially in patient groups with a high interindividual variability in pharmacokinetic (PK) parameters. One of these groups of patients is newborn children, for whom drug therapy, especially drugs with a narrow therapeutic range, causes a few difficulties or cannot be used in principle.The aim of the work was to develop and validate quantitative HPLC-MS/MS methods for the determination of vancomycin in “dried blood spot” samples using new protocols and comparison of the results obtained with the results in plasma samples using standard sample preparation methods.Materials and methods. To prepare stock and standard solutions of vancomycin and norvancomycin as an internal standard, dry portions of the corresponding certified standards of vancomycin (Servier, France) and norvancomycin (Augsburg, Germany, purity grade >95.0%) were used. A chromatographic separation of the components was carried out on a Poroshell 120 C18 column (4.6×50 mm, 2.7 µm). When developing conditions for a mass spectrometric detection of the desired substances using the multiple reaction monitoring (MRM) method, precursor ions and their corresponding product ions were determined.Results. A quantitative HPLC-MS/MS method for the determination of vancomycin in «dried blood spot» samples was developed and validated. A comparison was made between vancomycin concentrations in «dried blood spot» samples and plasma samples. Moreover, more than 95% of the calculated average concentrations are within the limits of d-2s and d+2s, which correspond to the values of –10.2 and 12.2. That confirms the suitability of the developed method for the analysis of patient samples.Conclusion. The results obtained make it possible for us to recommend the “dried blood spot” method for therapeutic monitoring of vancomycin, additional studies of PK in this group of patients with subsequent use of this drug in newborns and pediatric patients.

Streptococcus equinus keratitis after small-incision lenticule extraction: A case report and literature review

A 20-year-old male patient underwent small-incision lenticule extraction (SMILE) due to compound myopic astigmatism in both eyes. On the first day after SMILE, the patient was diagnosed with infectious keratitis (IK) caused by Streptococcus equinus. Emergency surgery was performed, and 2.5% vancomycin solution was used to wash the corneal interlamine of both eyes. After surgery, intensive antibiotic treatment and glucocorticoids were administered to reduce haze in the corneal epithelium and prevent corneal scar hyperplasia. IK was controlled in both eyes, and the uncorrected distance visual acuity in both eyes was 20/20.

Sellado antibiótico de reservorios subcutáneos: estabilidad de soluciones con vancomicina

Subcutaneous reservoirs are a type of central venous catheter. When using central venous catheters, healthcare workers need to avoid two major risks: clot formation and bacterial infections. To prevent and avoid catheter contamination in both hospitalized patients and outpatients, several strategies have been carried out, such as the so-called ” antibiotic-based catheter lock solution”. Therefore, it has been suggested to implement the use of solutions with antimicrobial agents, to which anticoagulant and/or antibiofilm substances are often added. However, the stability of such solutions needs to be tested by techniques such as high performance liquid chromatography (HPLC), in addition to antimicrobial efficacy testing, in order to establish patient safety. In consequence, this literature review aims to include the most clinically representative research towards these aspects, to demonstrate the behaviour of antibiotic-based catheter lock solutions under different conditions of storage and use. In particular, this review focuses on solutions containing vancomycin. According to the studies consulted, vancomycin solutions with sodium citrate (chelating agent) present the best stability characteristics in terms of physicochemical properties and efficacy.. Keywords: Vancomycin; heparin; sodium citrate; stability; subcutaneous implantable central venous device

Pharmacokinetics of Locally Applied Antibiotic Prophylaxis for Implant-Based Breast Reconstruction

Antibiotic irrigation of breast implants is widely used internationally, but no clinical study has investigated the pharmacokinetics of antibiotic prophylaxis in the breast implant pocket. To evaluate how long locally applied gentamicin, cefazolin, and vancomycin concentrations in the implant pocket remain above the minimum inhibitory concentration (MIC) for the most common bacterial infections and to measure systemic uptake. This prospective cohort study was performed at the Department of Plastic Surgery and Burns Treatment, Rigshospitalet, Copenhagen, Denmark, between October 25, 2021, and September 22, 2022, among 40 patients undergoing implant-based breast reconstruction who were part of the ongoing BREAST-AB trial (Prophylactic Treatment of Breast Implants With a Solution of Gentamicin, Vancomycin and Cefazolin Antibiotics for Women Undergoing Breast Reconstructive Surgery: a Randomized Controlled Trial). Patients were randomized to receive locally applied gentamicin, cefazolin, and vancomycin or placebo. Samples were obtained from the surgical breast drain and blood up to 10 days postoperatively. The breast implant and the implant pocket were irrigated with 160 μg/mL of gentamicin, 2000 μg/mL of cefazolin, and 2000 μg/mL of vancomycin in a 200-mL saline solution. The primary outcome was the duration of antibiotic concentrations above the MIC breakpoint for Staphylococcus aureus according to the Clinical and Laboratory Standards Institute: gentamicin, 4 μg/mL; cefazolin, 2 μg/mL; and vancomycin, 2 μg/mL. Secondary outcomes included the time above the MIC for Pseudomonas aeruginosa and other relevant bacteria, as well as systemic uptake. The study included 40 patients (median age, 44.6 years [IQR, 38.3-51.4 years]; median body mass index, 23.9 [IQR, 21.7-25.9]) with a median number of 3 drain samples (range, 1-10 drain samples) and 2 blood samples (range, 0-6 blood samples). Vancomycin and cefazolin remained above the MIC for S aureus significantly longer than gentamicin (gentamicin, 0.9 days [95% CI, 0.5-1.2 days] for blood samples vs 6.9 days [95% CI, 2.9 to 10.9 days] for vancomycin [P = .02] vs 3.7 days [95% CI, 2.2-5.2 days] for cefazolin [P = .002]). The gentamicin level remained above the MIC for P aeruginosa for 1.3 days (95% CI, 1.0-1.5 days). Only cefazolin was detectable in blood samples, albeit in very low concentrations (median concentration, 0.04 μg/mL [range, 0.007-0.1 μg/mL]). This study suggests that patients treated with triple-antibiotic implant irrigation during breast reconstruction receive adequate prophylaxis for S aureus and other common implant-associated, gram-positive bacteria. However, the protection against P aeruginosa may be inadequate.

Evaluation of Strategies for Reducing Vancomycin-Piperacillin/Tazobactam Incompatibility.

Drug incompatibility is defined as a physical-chemical reaction between two or more injectable drugs and that results mainly in precipitation or insolubility. Several strategies for reducing incompatibilities have been implemented empirically in intensive care units. However, these strategies have never been compared directly (and particularly in terms of the particulate load and drug mass flow rate) under standardized conditions. The objective of the present in vitro study was to evaluate the impact of various strategies for preventing incompatibility between simultaneously infused vancomycin and piperacillin/tazobactam. An in-line filter, a dilute vancomycin solution (5 mg/mL), and an alternative saline administration line were evaluated separately. The infusion line outlet was connected to a dynamic particle counter. The antibiotic concentration was measured in an HPLC-UV assay. The use of an in-line filter and an alternative saline administration route did not significantly reduce the particulate load caused by vancomycin-piperacillin/tazobactam incompatibility. Dilution of the vancomycin solution was associated with a significantly lower particulate load and maintenance of the vancomycin mass flow rate. It is important to systematically compare the efficacy of strategies for preventing drug incompatibility. The use of diluted vancomycin solution gave the best results in the case of vancomycin-piperacillin/tazobactam incompatibility.

Vancomycin Concentrations in Synovial Fluid Do Not Reach Chondrotoxic Thresholds After Anterior Cruciate Ligament Reconstruction With Vancomycin-Soaked Autologous Soft Tissue Grafts: An In Vivo Prospective Observational Study in Humans

Background: Studies have revealed that vancomycin soaking of the anterior cruciate ligament (ACL) graft can drastically reduce the incidence of postoperative infections after ACL reconstruction. However, it remains unknown whether the chondrotoxic threshold of vancomycin in synovial fluid is exceeded during this process. Several studies investigated the chondrotoxic properties of vancomycin in in vitro experiments and described a concentration of 1000 µg/mL as the critical threshold. Purpose/Hypothesis: The purpose of the study was to measure the vancomycin concentration in synovial fluid after ACL reconstruction with vancomycin-soaked autografts. It was hypothesized that intra-articular vancomycin concentrations in the synovial fluid would not reach the chondrotoxic threshold of 1000 µg/mL after vancomycin soaking of autologous semitendinosus tendon and soft tissue quadriceps tendon grafts for ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: The study enrolled 10 patients undergoing ACL reconstruction using 4-strand semitendinosus tendon autografts and 10 patients undergoing ACL reconstruction using soft tissue quadriceps tendon autografts. Before implantation, each harvested graft was intraoperatively wrapped in gauze swabs that had been soaked in a 5-mg/mL vancomycin solution. After wound closure, an aspirate of 5 mL of synovial fluid was taken from each patient. The vancomycin concentration of the aspirate was analyzed using high-performance liquid chromatography–tandem mass spectrometry. Spearman rho correlation coefficients were used to identify relationships between the parameters, and the t test was used to test for differences between graft types. A P value of <.05 was considered statistically significant. Results: The study included 20 patients (14 women and 6 men; age, 29.35 ± 11.3 years). The mean vancomycin concentration measured in the synovial fluid was 23.23 ± 21.68 µg/mL, with a minimum concentration of 2.32 µg/mL and a maximum concentration of 71.56 µg/mL. No significant difference was found between the 2 graft types (P = .911). Significant positive correlation (r = 0.644; P < .05) was observed only between the vancomycin concentration and the mean duration from initiation of vancomycin soaking of semitendinosus tendon grafts to implantation (13.4 ± 6 minutes). No correlations were observed between the vancomycin concentration and the duration from implantation to fluid aspiration or between the vancomycin concentration and the graft diameter (median, 8.5 mm; range, 6.0-10.0 mm) for both graft types. Conclusion: Chondrotoxic vancomycin concentrations ≥1000 µg/mL were not reached in any aspiration of synovial fluid after ACL reconstruction using soft tissue autografts that were intraoperatively soaked in a 5-mg/mL vancomycin solution. Against the backdrop of multiple studies that showed significantly reduced infection rates after ACL reconstruction when vancomycin soaking was used, this study suggests that the chondrotoxic properties of this method are negligible because of its submarginal intra-articular concentrations.

Evaluation of the original sealant with antibacterial effect for synthetic vascular grafts

Background: Vascular graft infection is a severe cardiovascular complication with high mortality rates. Antibacterial vascular graft coatings are widely used and continue to be improved.Objective: To develop a sealant with antimicrobial effect for Dacron vascular grafts and experimentally test the coating properties.Methods: We used 2 types of vascular grafts: graft No. 1 (plain weave) with initial water permeability of 78.8 ± 2.7 mL/cm2/min and graft No. 2 (2/1 twill + 6/4 satin weave) with water permeability of 549.8 ± 20.7 mL/cm2/min. We developed an original gelatin impregnation technique, tested it using a scanning electron microscopy, and measured water permeability and kink radius. We evaluated the antibacterial activity of vancomycin and gelatin impregnation by the disk diffusion test using media with Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and measured inhibition zones after 24-hour incubation. We used samples cut out of grafts with vancomycin-containing (experimental group) and no vancomycin-containing (control group) impregnation.Results: The gelatin coating of the samples is visualized as a thin even film and provides zero water permeability. On the negative side, it increased stiffness and the kink radius. Thanks to vancomycin added to the coating, bacterial growth significantly inhibits: the mean diameter of the growth inhibition zone for Staphylococcus aureus and Enterococcus faecalis was 15.60 ± 0.65 and 14.40 ± 0.66 mm, respectively. The grafts untreated with vancomycin showed no growth inhibition zones.Conclusion: Vascular graft treatment with gelatin impregnation and vancomycin solution is a simple measure to prevent the growth of gram-positive bacteria on vascular grafts. Received 14 November 2022. Revised 15 December 2022. Accepted 19 December 2022. Funding: The work was supported by Russian Science Foundation (project No. 22-15-20005). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: I.Yu. Zhuravleva, A.A. Shadanov, D.A. SirotaData collection and analysis: A.A. Shadanov, L.M. Samoylova, S.V. Vladimirov, T.P. Timchenko, N.E. Luchnikov, E.V. KarpovaStatistical analysis: A.A. ShadanovDrafting the article: A.A. Shadanov, L.M. Samoylova, T.P. Timchenko, A.G. EdemskiyCritical revision of the article: D.A. Sirota, I.Yu. Zhuravleva, A.V. Bogachev-Prokofiev, A.M. ChernyavskiyFinal approval of the version to be published: A.A. Shadanov, I.Yu. Zhuravleva, L.M. Samoylova, T.P. Timchenko, S.V. Vladimirov, E.V. Karpova, N.E. Luchnikov, D.A. Sirota, A.G. Edemskiy, A.V. Bogachev-Prokofiev, A.M. Chernyavskiy

Simple and rapid method for analysis of urinary vancomycin using solid phase extraction and fluorescence spectroscopy

Vancomycin (VCM) is an antimicrobial that is recommended for therapeutic drug monitoring (TDM) for maintaining the efficacy and safety of treatment. The trough monitoring has been used to guide VCM dosing regimens. However, newer guidelines recommend the use of area under the curve/minimum inhibitory concentration (AUC/MIC)-guided vancomycin dosing, and there is a need for easier and more frequent measurements of VCM concentrations. Therefore, in this study, we developed a simple and rapid analytical method for measuring urinary VCM by combining solid-phase extraction and fluorescence analysis. Urine samples are easier and less invasive than blood samples. In addition to the therapeutic range of blood VCM, this method was also able to measure 0.01–1 mg/mL, which is the concentration range of urinary VCM. The accuracy of 10, 20, and 30 μg/mL VCM solutions were between 93.18 and 109.76%. The relative standard deviation (RSD) of intra-day and inter-day analysis were less than 6.25% and 6.28%, respectively. Since this method does not use large equipment, it is expected to be better suited for clinical use.

Prophylactic treatment of breast implants with a solution of gentamicin, vancomycin and cefazolin antibiotics for women undergoing breast reconstructive surgery: protocol for a randomised, double-blind, placebo-controlled trial (The BREAST-AB trial)

IntroductionPeriprosthetic infection is one of the most severe complications following implant-based breast reconstruction affecting 5%–10% of the women. Currently, many surgeons apply antibiotics locally on the breast implant to reduce...

Identification of potentially irritating intravenous medications

AimsTo identify commonly used intravenous drugs that may produce endothelial damage. MethodsAn experimental research study was performed using a sample of 62 intravenous drugs commonly used in emergency care, pH and osmolarity were measured. Subsequently, based on these values, the theoretical capacity to cause irritation or endovascular damage was determined and classified as high, moderate, and low. ResultsSamples from 19 drugs for fluid therapy, 21 antibiotics and 22 drugs for intravenous use were studied. Glucose solutions, sodium bicarbonate 1M and mannitol 10% showed a high capacity to cause venous irritation. Vancomycin, ciprofloxacin, amiodarone, haloperidol, and labetalol solution presented a high capacity for irritation based on their acidic pH. The antibiotics, dexketoprofen, diazepam, digoxin, etomidate, phenytoin, levetiracetam and metamizole also showed high osmotic values in their reconstituted or undiluted presentations. Moreover, osmolarity of diazepam, digoxin and phenytoin remained high despite being diluted in 100 ml of saline. ConclusionsKnowing the pH and osmolarity of intravenous drugs allows their capacity to cause endothelial damage to be assessed. The use of comprehensive tables based on the chemical properties of the drugs can be a useful tool to help prevent chemically-induced phlebitis.

A Proposed Protective Protocol Predicting Reduction of Shunt Infection

To identify the best protective interventions against shunt infection and, hence, to find an appropriate protocol assumed to be associated with reduction of infection rates. A combined prospective-retrospective cohort study was conducted over a period of 5 years in 3 referral hospitals. Twelve interventions against infection practiced by blinded surgeons during ventriculoperitoneal shunt operations were surveyed and their association with the outcome of interest (i.e., shunt infection) was tested. Interventions proved to be associated with the outcome entered a multivariate logistic regression to identify the protective interventions. Among a total of 392 cases, shunt infection was diagnosed in 11.5% with a median onset of 55 days. Patients' demographics, etiology of hydrocephalus, shunt-related factors, and type of preoperative antibiotics were not associated with shunt infection. Two-thirds of infected shunts revealed Staphylococcus species. Among the tested interventions, double-gloving and device and wound irrigation using vancomycin solution and the use of incision adhesive drapes proved to exhibit a significant protective effect against shunt infection, whereas operative time <40 minutes revealed a marginal protective benefit. Shunt infection is a significant complication that occurs early during the first 2 months after surgery. According to the study findings, an appropriate protocol against shunt infection is assumed to be composed of double-gloving, device and wound irrigation using vancomycin solution, and the use of incision adhesive drapes. Reduced operative time had a beneficial effect against shunt infection, although it was of marginal significance in the current study.

Nitric Oxide-Releasing Lock Solution for the Prevention of Catheter-Related Infection and Thrombosis.

Although frequently used, venous catheters are often associated with serious complications such as infection and thrombosis. Lock solution therapies are clinically used to deter these issues but generally address only infection or thrombosis with limited success. Here, we report the development of a dual-functional lock therapy using nitric oxide (NO) donor molecule, S-nitrosoglutathione (GSNO). NO is a potent, broad-spectrum antimicrobial agent that also temporarily inhibits platelet activation, preventing thrombosis. Furthermore, NO has antibiofilm actions, an ability that traditional antibiotic lock solutions lack, thus limiting their efficacy. In this work, different concentrations of GSNO were characterized via NO analysis to determine a range of NO-releasing lock solution (NOreLS) concentrations to investigate and to demonstrate prolonged potential efficacy. Tested against clinically used vancomycin and gentamicin lock solutions, GSNO-based NOreLS repeatedly outperformed in models of different stages of catheter infections. NOreLS also prevented clot formation when exposed to whole blood, showing increased efficacy compared to a heparin lock solution. Moreover, NOreLS was demonstrated to be biocompatible via hemolysis and cytotoxicity assays. NOreLS has excellent potential for safely and effectively preventing infection and thrombosis related to catheter usage.

Enteral Vancomycin to Eliminate MRSA Carriership of the Digestive Tract in Critically Ill Patients.

Background: Carriership with methicillin resistant Staphylococcus aureus (MRSA) is a risk for the development of secondary infections in critically ill patients. Previous studies suggest that enteral vancomycin is able to eliminate enteral carriership with MRSA. Data on individual effects of this treatment are lacking. Methods: Retrospective analysis of a database containing 15 year data of consecutive patients from a mixed medical-(cardio)surgical 18 bedded intensive care unit was conducted. All consecutive critically ill patients with enteral MRSA carriership detected in throat and/or rectal samples were collected. We analyzed those with follow-up cultures to determine the success rate of enteral vancomycin. Topical application of 2% vancomycin in a sticky oral paste was performed combined with a vancomycin solution of 500 mg four times daily in the nasogastric tube. This treatment was added to a regimen of selective digestive tract decontamination (SDD) to prevent ICU acquired infection. Results: Thirteen patients were included. The mean age was 65 years and the median APACHE II score was 21. MRSA was present in the throat in 8 patients and in both throat and rectum in 5 patients. In all patients MRSA was successfully eliminated from both throat and rectum, which took 2–11 days with a median duration until decontamination of 4 days. Secondary infections with MRSA did not occur. Conclusions: Topical treatment with vancomycin in a 2% sticky oral paste four times daily in the nasogastric tube was effective in all patients in the elimination of MRSA and prevented secondary MRSA infections.

Evaluation of the Efficacy of Vancomycin-Soaked Autograft to Eliminate Staphylococcus aureus Contamination After Anterior Cruciate Ligament Reconstruction: Based on an Infected Rat Model

Background: Vancomycin-soaked autograft application in anterior cruciate ligament reconstruction (ACLR) significantly reduces postoperative infection rates. However, the optimal vancomycin concentrations and time of vancomycin presoaking of autografts for preventing infection are still unknown. Purpose: To evaluate the efficacy of vancomycin-soaked autografts in preventing infection in rats with ACLR. Study Design: Controlled laboratory study. Methods: A total of 102 tendons of Wistar rats were harvested under sterile conditions from fresh cadaveric legs. Contamination with 2.0 × 104 colony forming units per milliliter of Staphylococcus aureus and soaking in different vancomycin concentrations for different soaking times was performed in vitro. In vivo, after being contaminated with S. aureus and soaked with optimal vancomycin solution treatment and sterile saline, the grafts were implanted in rat knees to finish ACLR surgery. At 2, 4, and 12 weeks after surgery, samples were harvested to observe signs of infection and tendon-bone incorporation via general postoperative conditions, serum inflammatory markers, microbiological counting, knee radiographs, micro–computed tomography, histologic staining, scanning electron microscopy, and biomechanical testing. Results: Bacterial contamination was eliminated when at least 5 or 10 mg/mL of vancomycin was applied for 30 minutes in vitro. Rats in the vancomycin-soaked graft group (5 mg/mL of vancomycin for 30 minutes) showed no significant signs of infection and fewer positive cultures than did those without presoaking. The vancomycin-soaked graft group had reduced serum inflammatory markers, tissue scores, inflammatory reactions in the joint tissue, and radiographic evidence of periarticular osseous destruction compared with the control group. At postoperative week 12, the vancomycin-soaked graft group showed good outcomes in tendon-bone incorporation via micro–computed tomography, histologic staining, and biomechanical testing. Conclusion: In a rat model of infection after ACLR, presoaking grafts in a 5-mg/mL vancomycin solution for 30 minutes could effectively prevent S. aureus contamination without affecting tendon-bone incorporation and knee function. Clinical Relevance: The present study could provide a specific solution for the use of vancomycin in the prevention of infection after ACLR clinically.

Vancomycin lavage for the incidence of acute surgical site infection following primary total hip arthroplasty and total knee arthroplasty.

BACKGROUNDSurgical site infection is a rare but serious complication associated with total joint arthroplasty (TJA). There are limited data on the effectiveness of intrawound irrigation with vancomycin solution (1000 mg/L; 2 L) before wound closure for preventing acute surgical site infection following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).AIMTo investigate the effectiveness of prophylactic intraoperative application of vancomycin (1000 mg/L; 2 L) solution vs. plain irrigation in reducing the incidence of acute surgical site infection following primary THA and TKA.METHODSA retrospective review of 2725 consecutive patients undergoing THA or TKA from January 2012–December 2019 was performed. These patients received either intrawound irrigation with normal saline before wound closure between January 2012 and December 2015 (group 1, 1018 patients; 453 undergoing THA and 565 undergoing TKA) or intrawound irrigation with vancomycin solution (1000 mg/L) before wound closure between January 2016 and December 2019 (group 2, 1175 patients; 512 undergoing THA and 663 undergoing TKA). The outcomes were the incidences of postoperative surgical site infection and wound healing complications within 3 mo of primary TJA.RESULTSThere were no significant demographic differences between the 2 groups. There was a significantly higher incidence of acute infection at the surgical site in patients who received intrawound irrigation with normal saline before wound closure than in those who received intrawound irrigation with vancomycin solution (1000 mg/L; 2 L) before wound closure (overall incidence of infection: group 1, 2.46% vs group 2, 0.09%, P < 0.001). There was no significant difference in the incidence of wound healing complications between the two groups.CONCLUSIONProphylactic irrigation with vancomycin solution (1000 mg/L; 2 L) significantly decreases the incidence of acute surgical site infection after primary TJA. This strategy is a safe, efficacious, and inexpensive method for reducing the incidence of acute surgical site infection after TJA.

Вопросы патоморфологии и лечения тяжелых форм псевдомембранозного колита

Aim of study. To conduct a study of pathomorphological changes in the colon of patients with severe forms of pseudomembranous colitis and evaluate the possibilities in conservative and surgical treatment. Material and methods. Th e paper presents analysis of pathomorphological changes in the colon in patients with pseudomembranous colitis (PMC). Th e effectiveness of treatment with pseudomembranous colitis was evaluated for 45 patients, among which 30 (67 %) with moderate course underwent conservative therapy, including vancomycin and metronidazole, and 15 (33 %) patients with severe and complicated forms of PMC underwent surgical treatment. A total of 10 patients underwent organ-preserving surgeries with ileostomy (including its combination with sigmostomy) to exclude the colon from the passage with retrograde and its antegrade irrigation with vancomycin solution. Results. Histological examination revealed signifi cant changes in the intestinal wall in patients with PMC, characterised by cystic dilatation of crypts and glands, hypersecretion of mucus, followed by desquamation of the mucous membrane against the background of deep lymphocytic infi ltration. Th e duration of conservative treatment was 35.3±1.4 days. Along with the main laboratory parameters (signifi cant leukocytosis, stab shift to the left , an increase in the level of creatinine, C-reactive protein, a decrease in the amount of total protein), additional predictors of the failure of conservative therapy for PMC were identifi ed, including shock and the need for inotropic support, the need for mechanical ventilation, acute renal failure, organ dysfunction. Th e mortality rate amounted to 30 %. A total of 5 patients with a complicated course of the disease (toxic dilatation, perforation of the colon) underwent resection operations (colectomy – 4 and hemicolectomy – 1) according to vital indications. A total of 3 (75 %) patients died. Conclusion. It has been established that it is worth expanding the indications for surgical treatment of PMC if conservative therapy is ineffective, and it is possible to perform organ-preserving surgery aimed at shutting off the colon via ileostomy in the absence of severe surgical complications.