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Charles E Edmiston

Publications and source records attributed to Charles E Edmiston.

15 recordsLinked to original sources
PubMed2006

Bacterial adherence to surgical sutures: can antibacterial-coated sutures reduce the risk of microbial contamination?

BACKGROUND: Surgical site infections are associated with severe morbidity and mortality. The role of surgical sutures in the etiology of surgical site infection has been the objective of discussion for decades. This study used a standardized in vitro microbiologic model to assess bacterial adherence and the antibacterial activity of a triclosan-coated polyglactin 910 (braided) suture against selected Gram-positive and Gram-negative clinical isolates that may infect surgical wounds. STUDY DESIGN: Standardized cultures (2.0 log(10) colony forming units/mL and 5.0 log(10) colony forming units/mL of three clinical strains, Staphyllococcus aureus (methicillin-resistant S aureus [MRSA]), S epidermidis (biofilm-positive) and Escherichia coli (extended-spectrum beta-lactamase [ESBL]-producer) were inoculated to triclosan-coated and noncoated polyglactin 910 sutures to evaluate comparative adherence of bacterial isolates to the antibacterial coated and noncoated surgical sutures; to assess the impact of serum proteins (bovine serum albumin) on antibacterial activity of triclosan-coated suture; and to document the duration of antibacterial activity of the triclosan-coated material. Selected suture samples were prepared for scanning electron microscopy to demonstrate bacterial adherence. RESULTS: Substantial (p < 0.01) reductions in both Gram-positive and Gram-negative bacterial adherence were observed on triclosan-coated sutures compared with noncoated material. Pretreatment of surgical sutures with 20% BSA did not diminish antibacterial activity of the triclosan-coated braided device compared with noncoated suture (p < 0.01), and antibacterial activity was documented to persist for at least 96 hours compared with controls (p < 0.01). CONCLUSIONS: The in vitro model demonstrated a considerable reduction (p < 0.01) in Gram-positive and Gram-negative bacterial adherence to a triclosan-coated braided suture, which was associated with decreased microbial viability (p < 0.001). Because bacterial contamination of suture material within a surgical wound may increase the virulence of a surgical site infection, treating the suture with triclosan provides an effective strategy for reducing perioperative surgical morbidity.

Anti-Infective Agents, Local↗
PubMed2006

Impact of selective antimicrobial agents on staphylococcal adherence to biomedical devices.

BACKGROUND: Infection of intravascular or implanted biomedical devices often involves biofilm-forming staphylococci that are recalcitrant to antimicrobial therapy. The present study investigated the activity of 6 antimicrobial agents against biofilm-forming and non-biofilm-forming strains of staphylococci adherent to the surface of selected biomedical devices. METHODS: Five clinical staphylococcal strains were selected for study in (1) antibiotic-lock model (ALM) and (b) vascular graft model (Dacron and expanded polytetrafluoroethylene [ePFTE]) devices. Test strains were inoculated for 30 minutes to stabilize microbial adherence and then exposed to antibiotic; the impact on bacterial adherence was assessed at 1, 2, 4, 7, and 10 days. RESULTS: Regarding ALM, daptomycin and rifampin were effective at eradicating staphylococcal adherence by day 4 (P<.01); linezolid and gentamicin by day 7 (P<.01); vancomycin by day 7; and ceftriaxone failed to eradicate staphylococcal adherence in 4 of 5 strains by day 10. Regarding ePTFE, daptomycin and linezolid eradicated staphylococcal adherence by day 2 (P<.01); rifampin by day 4 (P<.01); vancomycin and gentamicin by day 7 (P<.01); and ceftriaxone failed to eliminate staphylococcal adherence in 3 of 5 strains by day 10. Regarding Dacron, daptomycin and rifampin eradicated adherent strains by day 4 (P<.01); linezolid by day 7 (P<.01), and vancomycin, gentamicin, and ceftriaxone decreased staphylococcal adherence by 90%, 95%, and 78%, respectively, by day 10. COMMENTS: Daptomycin, rifampin, and linezolid demonstrated greater efficacy and speed in eradicating microbial adherence of staphylococcal isolates from selected devices compared with vancomycin, gentamicin, or ceftriaxone (P<.01). Further studies are warranted, however, to validate the clinical efficacy of daptomycin and linezolid in the treatment of biomedical device-associated infections.

Acetamides↗
PubMed2005

Comparative in vitro antimicrobial activity of a novel quinolone, garenoxacin, against aerobic and anaerobic microbial isolates recovered from general, vascular, cardiothoracic and otolaryngologic surgical patients.

OBJECTIVES: The aim of the study was to analyse the susceptibility of unique and non-duplicate aerobic and anaerobic isolates from surgical patients to a novel des-F(6)-quinolone (garenoxacin) and other selected antimicrobial agents. METHODS: Eleven hundred and eighty-five aerobic and anaerobic isolates from general, vascular, cardiothoracic and otolaryngologic surgical patients were tested for susceptibility to garenoxacin and seven other antibiotics (ciprofloxacin, moxifloxacin, levofloxacin, piperacillin/tazobactam, imipenem, clindamycin and metronidazole) using the referenced microbroth and agar-dilution method. RESULTS: Garenoxacin exhibited greater antimicrobial activity than comparator quinolones such as ciprofloxacin, levofloxacin and other antimicrobials when tested against selected gram-positive organisms. The in vitro aerobic and anaerobic activity of garenoxacin was similar to that of moxifloxacin. All fluoroquinolones tested were effective against most gram-negative facultative anaerobes including Escherichia coli. Garenoxacin and moxifloxacin demonstrated similar in vitro antimicrobial activity against selected anaerobic gram-positive and gram-negative anaerobic bacteria such as members of the Bacteroides fragilis group. Overall, the in vitro activity of the advanced spectrum quinolones against anaerobic surgical isolates compared favourably with selected comparator agents, metronidazole, imipenem and piperacillin/tazobactam. CONCLUSIONS: These findings suggest that 82.4% of aerobic surgical isolates were susceptible to a concentration of garenoxacin < or = 1.0 mg/L, whereas 84.5% of the anaerobic isolates were susceptible to a garenoxacin concentration < or = 1.0 mg/L. Garenoxacin may be a valuable surgical anti-infective for treatment of serious head and neck, soft tissue, intra-abdominal and diabetic foot infections.

Anti-Bacterial Agents↗
PubMed2005

Microbiology of middle ear effusions from 292 patients undergoing tympanostomy tube placement for middle ear disease.

OBJECTIVE: Otitis media is one of the most commonly diagnosed childhood illnesses. Ideally, culture directed therapy for otitis media would be available, however, the common approach is to treat infections with antibiotics that cover the most common pathogens. The objective of this study is to describe the pathogens cultured from the middle ear effusions (MEE) of patients that underwent tympanostomy tube placement for middle ear disease, compare these results with previous studies, and assess for trends suggestive of changes in the microbiology of these patients. METHODS: Patients were invited to participate after the decision to place ventilation tubes had been made. A standard anterior-inferior myringotomy was made for placement of the ventilation tube. After myringotomy, patients had their ears suctioned and all effusions were collected for microbiologic analysis. RESULTS: A total of 292 patients were enrolled in the study, a total of 270 MEE samples were taken. Haemophilus influenzae and Moraxella catarrhalis were seen in 24 of 148 (16.2%) and 15 of 148 (10.1%), respectively. Neisseria meningitidis, Staphylococcus aureus and Corynebacterium species were each identified in 11 of the 148 pathogens isolated (7.4%). Streptococcus pneumoniae was identified in 6 of the 148 isolated pathogens (4.1%). CONCLUSION: Despite a high number of non-pathogenic bacteria, and a high number of culture negative effusions, we demonstrated pathogen rates consistent with other reports in the literature. Future directions include using more specific techniques such as PCR to better understand the microbiology of middle ear effusions.

Candida↗
PubMed2005

Operative strategies in aortic graft infections: is complete graft excision always necessary?

The classic approach to aortic graft infections involves complete excision of the graft material with remote reconstruction of the distal circulation. Certain patients may not be well suited for this approach for physiologic or anatomic reasons. This study was undertaken to determine the outcome of partial graft excision in selected patients with aortic graft infection who were not felt to be candidates for complete graft excision. Retrospective analysis of 30 consecutive patients treated with infected grafts arising from the aorta over the past 10 years was performed. Mean interval between graft placement and infection was 5.5 years. Complete graft excision with bypass via clean tissue planes was achieved in 15 patients (group A), and partial or complete graft salvage or in situ graft replacement was performed at the discretion of the surgeon in 15 patients (group B). Perioperative mortality occurred in eight subjects (27%), including six in group A (40%) and two in group B (13%; p = NS). Six patients (20%) developed recurrent infection following graft excision, two (13%) in group A and four (27%) in group B (p = NS). Microorganisms were recovered from 24 of 30 (80%) graft cultures: 13 (43%) were gram positive, 4 (13%) were gram negative, and both gram-positive and gram-negative organisms were recovered from 7 (23%). Identification of culture isolates did not influence either perioperative mortality or the development of recurrent infection. Long-term survival was no different between the groups. We conclude that in certain high-risk patients who may not tolerate complete graft excision, local resection of infected graft segments may be preferable and leads to similar short- and long-term outcome.

Aged↗
PubMed2005

Molecular epidemiology of microbial contamination in the operating room environment: Is there a risk for infection?

BACKGROUND: Modern operating rooms are considered to be aseptic environments. The use of surgical mask, frequent air exchanges, and architectural barriers are used to reduce airborne microbial populations. Breaks in surgical technique, host contamination, or hematogenous seeding are suggested as causal factors in these infections. This study implicates contamination of the operating room air as an additional etiology of infection. METHODS: To investigate the potential sources of perioperative contamination, an innovative in situ air-sampling analysis was conducted during an 18-month period involving 70 separate vascular surgical procedures. Air-sample cultures were obtained from multiple points within the operating room, ranging from 0.5 to 4 m from the surgical wound. Selected microbial clonality was determined by pulse-field gel electrophoresis. In a separate series of studies microbial nasopharyngeal shedding was evaluated under controlled environmental conditions in the presence and absence of a surgical mask. RESULTS: Coagulase-negative staphylococci were recovered from 86% of air samples, 51% from within 0.5 m of the surgical wound, whereas Staphylococcus aureus was recovered from 64% of air samples, 39% within 0.5 m from the wound. Anterior nares swabs were obtained from 11 members of the vascular team, clonality was observed between 8 strains of S epidermidis, and 2 strains of S aureus were recovered from selected team members and air-samples collected throughout the operating room environment. Miscellaneous Gram-negative isolates were recovered less frequently (<33%); however, 7 isolates expressed multiple patterns of antimicrobial resistance. The traditional surgical mask demonstrated limited effectiveness at curtailing microbial shedding, especially during symptomatic periods of rhinorrhea. CONCLUSIONS: Gram-positive staphylococcal isolates were frequently isolated from air samples obtained throughout the operating room, including areas adjacent to the operative field. Nasopharyngeal shedding from person participating in the operation was identified as the source of many of these airborne contaminants. Failure of the traditional surgical mask to prevent microbial shedding is likely associated with an increased risk of perioperative contamination of biomedical implants, especially in procedures lasting longer than 90 minutes.

Air Microbiology↗
PubMed2005

A murine model of invasive aspergillosis: variable benefit of interferon-gamma administration under in vitro and in vivo conditions.

BACKGROUND: Interferon-gamma modulates host defense in a number of infectious diseases. Previous studies have shown that systemic administration of interferon-gamma (IFN-gamma) can enhance survival in experimental invasive aspergillosis (IA). METHODS: Using a novel model of murine IA that is characterized by primary pulmonary infection, we investigated the role of IFN-gamma in the phagocytosis and killing of Aspergillus fumigatus by murine neutrophils and pulmonary alveolar macrophages in vitro and the impact of systemic and regional administration of IFN-gamma on the course of IA in glucocorticoid-treated mice. RESULTS: In vitro, IFN-gamma significantly enhanced phagocytosis and killing function of both neutrophils and alveolar macrophages from normal animals, but not cortisone-treated animals. In vivo, intravenous administration of IFN-gamma did not improve phagocyte recruitment, in vivo killing, or mortality from IA. Regional (intranasal) administration of IFN-gamma to the lungs enhanced recruitment of phagocytic cells to the lungs and improved in vivo killing, but did not alter (and actually worsened) mortality from IA. CONCLUSIONS: The in vitro and in vivo effects of IFN-gamma in IA are contingent on many variables, including the route of administration and the specific pathogenesis of infection.

Animals↗
PubMed2004

Perioperative antibiotic prophylaxis in the gastric bypass patient: do we achieve therapeutic levels?

BACKGROUND: Perioperative surgical antibiotic prophylaxis requires that therapeutically effective drug concentrations be present in the tissues. METHODS: Patients undergoing Roux-en-Y gastric bypass for morbid obesity were given 2 g cefazolin preoperatively, followed by a second dose at 3 hours. Thirty-eight patients were each assigned to 1 of 3 body mass index (BMI) groups: (A) BMI=40-49 (N = 17); (B) BMI=50-59 (N=11); (C) BMI > or= 60 (N=10). Multiple timed serum (baseline; incision, 15, 30, 60 minutes; prior to second prophylactic dose; and closure) and tissue (skin, subcutaneous fat, and omentum) specimens were collected and cefazolin concentration analyzed by microbiological assay. RESULTS: No significant difference was observed in intraoperative fluid replacement or blood loss among BMI groups. Serum antimicrobial concentrations exceeded resistance breakpoint (32 microg/mL) in 73%, 68%, and 52% of BMI groups A, B, and C, respectively. No significant difference in cefazolin concentration was observed in mean incisional skin and closure tissue specimens in groups A, B, and C. A significant decrease in cefazolin concentration was noted in closure adipose (p=.04), initial (p=.03) and closure omentum (p=.05) tissues in groups B and C compared with A. Over 90% of serum samples exhibited therapeutic concentrations covering 53.8% of gram-positive and 78.6% of gram-negative surgical pathogens. However, therapeutic tissue levels were achieved in only 48.1%, 28.6%, and 10.2% of groups A, B, and C, respectively. CONCLUSIONS: Pharmacokinetic analysis suggests that present dosing strategies may fail to provide adequate perioperative prophylaxis in gastric bypass patients.

Adult↗
PubMed2004

Fungal biofilm formation on cochlear implant hardware after antibiotic-induced fungal overgrowth within the middle ear.

Cochlear implantation in patients with chronic suppurative otitis media is managed with perioperative antibiotics; however, fungal overgrowth can occur. We present a child who received oral cefdinir and topical ofloxacin (Floxin). After 6 weeks, a fungal (Candida) biofilm was demonstrated on the implant surface. In this clinical setting, an antimicrobial strategy using an oral antifungal to prevent fungal overgrowth is a possibility.

Anti-Infective Agents↗
PubMed2004

In vitro activities of moxifloxacin against 900 aerobic and anaerobic surgical isolates from patients with intra-abdominal and diabetic foot infections.

The in vitro activities of moxifloxacin, ciprofloxacin, levofloxacin, gatifloxacin, imipenem, piperacillin-tazobactam, clindamycin, and metronidazole against 900 surgical isolates were determined using NCCLS testing methods. Moxifloxacin exhibited good to excellent antimicrobial activity against most aerobic (90.8%) and anaerobic (97.1%) microorganisms, suggesting that it may be effective for the treatment of polymicrobial surgical infections.

Abdomen↗
PubMed2003

Meningitis due to Enterobacter aerogenes subsequent to resection of acoustic neuroma and percutaneous endoscopic gastrostomy tube placement: a rare nosocomial event.

We present a case of meningitis after percutaneous endoscopic gastrostomy (PEG) tube placement subsequent to acoustic neuroma resection and cranioplasty. Four days following PEG tube placement, the patient developed Enterobacter aerogenes meningitis, requiring explantation of infected cranioplasty material. His condition subsequently improved. Etiology and future intervention strategies are discussed.

Adult↗
PubMed2002

Anaerobic infections in the surgical patient: microbial etiology and therapy.

Anaerobic infections occur in surgical patients in part because of structural or functional defects in the host that (1) cause a breech in the normal mucosal barriers, (2) create localized vascular insufficiencies, or (3) produce an obstruction. Any or all of these events may compromise the oxidation-reduction potential within the tissues, encouraging rapid anaerobic growth. Although diverse anaerobic populations are spread throughout the gastrointestinal tract, a relatively limited number of organisms are responsible for clinical infection in the surgical patient. Many of these offending organisms express overt virulence factors that enhance microbial adherence, tissue destruction, and, in the case of Bacteroides fragilis, facilitate abscess formation. The selection of an appropriate perioperative or therapeutic agent requires a fundamental knowledge of the microbial ecology of this microbial population. The failure to consider the anaerobic flora as a component in the etiology of mixed surgical infections is associated with a high rate of perioperative and therapeutic failures.

Bacteria, Anaerobic↗
PubMed2002

Activity of antibacterial impregnated central venous catheters against Klebsiella pneumoniae.

OBJECTIVE: Antibiotically coated or impregnated catheters are effective in eliminating gram-positive bacteria from their surfaces. However, their activity against gram-negative bacteria is not well known. The aim of this study was to evaluate and compare the adherence, persistence and colonization of Klebsiella pneumoniae on catheter surfaces and also to assess bacteriostatic and bactericidal levels. DESIGN: Randomized, controlled, laboratory study. SETTING: University surgical microbiology laboratory. SUBJECTIVE: Silver sulfadiazine-chlorhexidine impregnated (SSC), minocycline and rifampin bonded (M+R), silver, platinum and carbon incorporated (SP+C) and non-antiseptic central venous catheter segments. INTERVENTIONS: Catheter segments were immersed in 1 ml of phosphate buffered saline (0.01 mol/l) with 0.25% dextrose (PBSD) and incubated at 37 degrees C. The PBSD was replaced daily. Effluents were frozen at -70 degrees C for subsequent determination of bacteriostatic and bactericidal activity. On days 1,3,7,14 and 21 after initial immersion, 1 ml standardized inoculum of Klebsiella pneumoniae was added to 90 tubes for a period of 30 min. The inoculum was then replaced with PBSD. One third of the samples were immediately sonicated and plated for the determination of bacterial adherence. The remaining segments were incubated for 4 and 24 h, followed by the same procedure to determine bacterial persistence and colonization with time. All plates were read after 24 h of incubation. MEASUREMENTS AND RESULTS: There was a significant reduction in initial bacterial adherence for SP+C catheters on all days ( p<0.05). SSC catheters prevented initial bacterial adherence for the first 7 days only ( p<0.05). SSC and SP+C catheters prevented bacterial persistence and further colonization on all days. However M+R catheters prevented bacterial colonization for 3 days only. Effluent studies indicated that the impregnated agents in catheter SSC were bactericidal compared to catheter M+R, which were bacteriostatic to K. pneumoniae. No antibacterial activity was detected in the effluents from catheter SP+C. CONCLUSIONS: SSC and SP+C catheters are effective in eliminating K. pneumoniae from their surfaces for at least 21 days. M+R catheters are less effective in eliminating bacterial adherence and colonization may be due to their bacteriostatic property.

Analysis of Variance↗