Enhanced chlorhexidine skin penetration with 1,8-cineole.

BACKGROUND: Chlorhexidine (CHG) penetrates poorly into skin. The purpose of this study was to compare the depth of CHG skin permeation from solutions containing either 2% (w/v) CHG and 70% (v/v) isopropyl alcohol (IPA) or 2% (w/v) CHG, 70% (v/v) IPA and 2% (v/v) 1,8-cineole. METHODS: An ex-vivo study using Franz diffusion cells was carried out. Full thickness human skin was mounted onto the cells and a CHG solution, with or without 2% (v/v) 1,8-cineole was applied to the skin surface. After twenty-four hours the skin was sectioned horizontally in 100 µm slices to a depth of 2000 µm and the concentration of CHG in each section quantified using high performance liquid chromatography (HPLC). The data were analysed with repeated measures analysis of variance. RESULTS: The concentration of CHG in the skin on average was significantly higher (33.3% [95%, CI 1.5% - 74.9%]) when a CHG solution which contained 1,8-cineole was applied to the skin compared to a CHG solution which did not contain this terpene (P = 0.042). CONCLUSIONS: Enhanced delivery of CHG can be achieved in the presence of 1,8-cineole, which is the major component of eucalyptus oil. This may reduce the numbers of microorganisms located in the deeper layers of the skin which potentially could decrease the risk of surgical site infection.

Liver metastases from esophageal carcinoma: is there a role for surgical resection?

Esophageal cancer recurrence rates after esophagectomy are high, and locally recurrent or distant metastatic disease has poor prognosis. Management is limited to palliative chemotherapy and symptomatic interventions. We report our experience of four patients who have undergone successful liver resection for metastases from esophageal cancer. All underwent esophagectomy and were referred to our unit with metastatic recurrent liver disease, two with solitary metastases and two with multi-focal disease. The patients underwent multidisciplinary assessment and proceeded to a course of neoadjuvant chemotherapy followed by open or laparoscopic liver resection. Three patients were male, and the mean age was 57.5 (range 44-71) years. Response to chemotherapy ranged from partial to complete response. Following liver resection, two patients developed recurrent disease at 5 and 15 months, and both had disease-specific mortality at 10 and 21 months, respectively. The other two patients remain disease free at 22 and 92 months. Recurrent metastatic esophageal cancer continues to have a poor prognosis, and the majority of patients with liver involvement will not be candidates for hepatic resection. However, this series suggests that in selected patients, liver resection of metastases from esophageal cancer combined with neoadjuvant and adjuvant chemotherapy is feasible, but further research is required to determine whether this can offer a survival advantage.

Randomized clinical trial on enhanced recovery versus standard care following open liver resection.

BACKGROUND: Enhanced recovery programmes (ERPs) have been shown to reduce length of hospital stay (LOS) and complications in colorectal surgery. Whether ERPs have the same benefits in open liver resection surgery is unclear, and randomized clinical trials are lacking. METHODS: Consecutive patients scheduled for open liver resection were randomized to an ERP group or standard care. Primary endpoints were time until medically fit for discharge (MFD) and LOS. Secondary endpoints were postoperative morbidity, pain scores, readmission rate, mortality, quality of life (QoL) and patient satisfaction. ERP elements included greater preoperative education, preoperative oral carbohydrate loading, postoperative goal-directed fluid therapy, early mobilization and physiotherapy. Both groups received standardized anaesthesia with epidural analgesia. RESULTS: The analysis included 46 patients in the ERP group and 45 in the standard care group. Median MFD time was reduced in the ERP group (3 days versus 6 days with standard care; P < 0·001), as was LOS (4 days versus 7 days; P < 0·001). The ERP significantly reduced the rate of medical complications (7 versus 27 per cent; P = 0·020), but not surgical complications (15 versus 11 per cent; P = 0·612), readmissions (4 versus 0 per cent; P = 0·153) or mortality (both 2 per cent; P = 0·987). QoL over 28 days was significantly better in the ERP group (P = 0·002). There was no difference in patient satisfaction. CONCLUSION: ERPs for open liver resection surgery are safe and effective. Patients treated in the ERP recovered faster, were discharged sooner, and had fewer medical-related complications and improved QoL. REGISTRATION NUMBER: ISRCTN03274575 (http://www.controlled-trials.com).

Liver resection for colorectal cancer metastases involving the caudate lobe.

BACKGROUND: Up to 5 per cent of liver resections for colorectal cancer metastases involve the caudate lobe, with cancer-involved resection margins of over 50 per cent being reported following caudate lobe resection. METHODS: Outcomes of consecutive liver resections for colorectal metastases involving the caudate lobe between 1996 and 2009 were reviewed retrospectively, and compared with those after liver surgery without caudate resection. RESULTS: Twenty-five patients underwent caudate and 432 non-caudate liver resection. Caudate resection was commonly performed as part of extended resection. There were no differences in operative complications (24 versus 21·1 per cent; P = 0·727) or blood loss (median 300 versus 250 ml; P = 0·234). The operating time was longer for caudate resection (median 283 versus 227 min; P = 0·024). Tumour size was larger in the caudate group (median 40 versus 27 mm; P = 0·018). Resection margins were smaller when the caudate lobe was involved by tumour, than in resections including tumour-free caudate or non-caudate resection; however, there was no difference in the proportion of completely excised tumours between caudate and non-caudate resections (96 versus 96·1 per cent; P = 0·990). One-year overall survival rates were 90 and 89·3 per cent respectively (P = 0·960), with 1-year recurrence-free survival rates of 62 and 71·2 per cent (P = 0·340). CONCLUSION: Caudate lobe surgery for colorectal cancer liver metastases does not increase the incidence of resection margin involvement, although when the caudate lobe contains metastases the margins are significantly closer than in other resections.

Histidine acts as a co-germinant with glycine and taurocholate for Clostridium difficile spores.

AIMS: It is well established that the bile salt sodium taurocholate acts as a germinant for Clostridium difficile spores and the amino acid glycine acts as a co-germinant. The aim of this study was to determine whether any other amino acids act as co-germinants. METHODS AND RESULTS: Clostridium difficile spore suspensions were exposed to different germinant solutions comprising taurocholate, glycine and an additional amino acid for 1 h before heating shocking (to kill germinating cells) or chilling on ice. Samples were then re-germinated and cultured to recover remaining viable cells. Only five amino acids out of the 19 common amino acids tested (valine, aspartic acid, arginine, histidine and serine) demonstrated co-germination activity with taurocholate and glycine. Of these, only histidine produced high levels of germination (97·9-99·9%) consistently in four strains of Cl. difficile spores. Some variation in the level of germination produced was observed between different PCR ribotypes, and the optimum concentration of amino acids with taurocholate for the germination of Cl. difficile NCTC 11204 spores was 10-100 mmol l-1. CONCLUSIONS: Histidine was found to be a co-germinant for Cl. difficile spores when combined with glycine and taurocholate.

Serum procalcitonin, interleukin-6, soluble intercellular adhesin molecule-1 and IgG to short-chain exocellular lipoteichoic acid as predictors of infection in total joint prosthesis revision.

The diagnosis of prosthetic joint infection and its differentiation from aseptic loosening remains problematic. The definitive laboratory diagnostic test is the recovery of identical infectious agents from multiple intraoperative tissue samples; however, interpretation of positive cultures is often complex as infection is frequently associated with low numbers of commensal microorganisms, in particular the coagulase-negative staphylococci (CNS). In this investigation, the value of serum procalcitonin (PCT), interleukin-6 (IL-6) and soluble intercellular adhesion molecule-1 (sICAM-1) as predictors of infection in revision hip replacement surgery is assessed. Furthermore, the diagnostic value of serum IgG to short-chain exocellular lipoteichoic acid (sce-LTA) is assessed in patients with infection due to CNS. Presurgical levels of conventional serum markers of infection including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and white blood cell count (WBC) is also established. Forty-six patients undergoing revision hip surgery were recruited with a presumptive clinical diagnosis of either septic (16 patients) or aseptic loosening (30 patients). The diagnosis was confirmed microbiologically and levels of serum markers were determined. Serum levels of IL-6 and sICAM-1 were significantly raised in patients with septic loosening (P = 0.001 and P = 0.0002, respectively). Serum IgG to sce-LTA was elevated in three out of four patients with infection due to CNS. In contrast, PCT was not found to be of value in differentiating septic and aseptic loosening. Furthermore, CRP, ESR and WBC were significantly higher (P = 0.0001, P = 0.0001 and P = 0.003, respectively) in patients with septic loosening. Serum levels of IL-6, sICAM-1 and IgG to sce-LTA may provide additional information to facilitate the diagnosis of prosthetic joint infection.

The drugs don't work: evaluation of educational theatre to gauge and influence public opinion on antimicrobial resistance.

Increased public awareness of antimicrobial resistance (AMR) is a key component of effective antimicrobial stewardship strategies. Educational theatre combined with an expert panel was used to engage the public about AMR through delivery of a play entitled 'The drugs don't work'. Audience knowledge and understanding of AMR were measured by pre- and post-play questionnaires. Performance of the play and discussion with the expert panel significantly improved audience knowledge and understanding of AMR, including antibiotic misuse and prescribing. Educational theatre provides a positive learning experience and is an innovative method of public engagement to disseminate important public health messages.

Antimicrobial efficacy of eucalyptus oil and 1,8-cineole alone and in combination with chlorhexidine digluconate against microorganisms grown in planktonic and biofilm cultures.

OBJECTIVES: Effective disinfection and antisepsis is pivotal in preventing infections within the healthcare setting. Chlorhexidine digluconate (CHG) is a widely used disinfectant/antiseptic possessing broad-spectrum antimicrobial activity; however, its penetration into bacterial biofilms and human skin is poor. The aim of this study was to investigate the antimicrobial efficacy of crude eucalyptus oil (EO) and its main component 1,8-cineole (a recognized permeation enhancer), alone and in combination with CHG, against a panel of clinically relevant microorganisms grown in planktonic and biofilm cultures. METHODS: MICs and minimum bactericidal/fungicidal concentrations were determined for each microorganism grown in suspension and biofilm using microbroth dilution and ATP bioluminescence, respectively. Chequerboard assays were used to determine synergistic, indifferent or antagonistic interactions between CHG and EO or 1,8-cineole. RESULTS: Antimicrobial activity was demonstrated by CHG, EO and 1,8-cineole; however, CHG was significantly more active against microorganisms in both planktonic and biofilm modes of growth (P < 0.05). Crude EO was significantly more efficacious against microorganisms grown in suspension compared with 1,8-cineole (P < 0.05). Synergistic activity was demonstrated between CHG and both EO and 1,8-cineole against suspensions of Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Escherichia coli and Candida albicans, and biofilm cultures of MRSA and Pseudomonas aeruginosa. CONCLUSIONS: In conclusion, CHG may be combined with either crude EO or its major component 1,8-cineole for enhanced, synergistic antimicrobial activity against a wide range of microorganisms in planktonic and biofilm modes of growth; however, the superior antimicrobial efficacy associated with crude EO alone, compared with 1,8-cineole, favours its combination with CHG.

The antimicrobial efficacy of zinc doped phosphate-based glass for treating catheter associated urinary tract infections.

In this study, a series of phosphate-based glasses; (P2O5)50(Na2O)20(CaO)30-x (ZnO)x were prepared with increasing concentration of zinc oxide to determine the antimicrobial effect against clinically relevant microorganisms. The addition of 1 and 3 mol% zinc oxide decreased glass degradation however a higher dissolution rate was observed for 5 and 10 mol% ZnO. The antimicrobial results showed a concentration dependent effect on the viability of microorganisms. When in direct contact zinc doped glasses showed a complete kill, within 24 h, against Escherichia coli and a significant (p < 0.01) kill was observed against Staphylococcus aureus however the effect of dissolution products was not seen until 48 h. Furthermore, the cytotoxic studies showed no toxic effects on the viability of uroepithelial cells. This study has shown that zinc doped phosphate-based glasses can potentially be used to prevent/treat catheter associated urinary tract infections.

The Antimicrobial Efficacy of Hypoxia Mimicking Cobalt Oxide Doped Phosphate-Based Glasses against Clinically Relevant Gram Positive, Gram Negative Bacteria and a Fungal Strain.

Bioactive phosphate glasses are of considerable interest for a range of soft and hard tissue engineering applications. The glasses are degradable and can release biologically important ions in a controlled manner. The glasses can also potentially be used as an antimicrobial delivery system. In the given study, novel cobalt-doped phosphate-based glasses, (P2O5)50(Na2O)20(CaO)30-x(CoO)x where 0 ≤ x (mol %) ≤ 10, were manufactured and characterized. As the cobalt oxide concentration increased, the rate of dissolution was observed to decrease. The antimicrobial potential of the glasses was studied using direct and indirect contact methods against both Escherichia coli (NCTC 10538) Staphylococcus aureus (ATCC 6538) and Candida albicans (ATCC 76615). The results showed strong, time dependent, and strain specific antimicrobial activity of the glasses against microorganisms when in direct contact. Antimicrobial activity (R) ≥ 2 was observed within 2 h against Escherichia coli, whereas a similar effect was achieved in 6 h against Staphylococcus aureus and Candida albicans. However, when in indirect contact, the dissolution products from the bioactive glasses failed to show an antimicrobial effect. Following direct exposure to the glasses for 7 days, osteoblast-like SAOS-2 cells showed a 5-fold increase in VEGF mRNA while THP-1 monocytic cells showed a 4-fold increase in VEGF mRNA expression when exposed to 10% CoO-doped glass compared with the cobalt free control glass. Endothelial cells stimulated with conditioned medium taken from cell cultures of THP-1 monocytes exposed to 10% CoO doped glass showed clear tubelike structure (blood vessel) formation after 4 h.

Penetration of chlorhexidine into human skin.

This study evaluated a model of skin permeation to determine the depth of delivery of chlorhexidine into full-thickness excised human skin following topical application of 2% (wt/vol) aqueous chlorhexidine digluconate. Skin permeation studies were performed on full-thickness human skin using Franz diffusion cells with exposure to chlorhexidine for 2 min, 30 min, and 24 h. The concentration of chlorhexidine extracted from skin sections was determined to a depth of 1,500 microm following serial sectioning of the skin using a microtome and analysis by high-performance liquid chromatography. Poor penetration of chlorhexidine into skin following 2-min and 30-min exposures to chlorhexidine was observed (0.157 +/- 0.047 and 0.077 +/- 0.015 microg/mg tissue within the top 100 microm), and levels of chlorhexidine were minimal at deeper skin depths (less than 0.002 microg/mg tissue below 300 microm). After 24 h of exposure, there was more chlorhexidine within the upper 100-microm sections (7.88 +/- 1.37 microg/mg tissue); however, the levels remained low (less than 1 microg/mg tissue) at depths below 300 microm. There was no detectable penetration through the full-thickness skin. The model presented in this study can be used to assess the permeation of antiseptic agents through various layers of skin in vitro. Aqueous chlorhexidine demonstrated poor permeation into the deeper layers of the skin, which may restrict the efficacy of skin antisepsis with this agent. This study lays the foundation for further research in adopting alternative strategies for enhanced skin antisepsis in clinical practice.

Antimicrobial efficacy of copper surfaces against spores and vegetative cells of Clostridium difficile: the germination theory.

OBJECTIVES: Persistent contamination of surfaces by spores of Clostridium difficile is a major factor influencing the spread of C. difficile-associated diarrhoea (CDAD) in the clinical setting. In recent years, the antimicrobial efficacy of metal surfaces has been investigated against microorganisms including methicillin-resistant Staphylococcus aureus. This study compared the survival of C. difficile on stainless steel, a metal contact surface widely used in hospitals, and copper surfaces. METHODS: Antimicrobial efficacy was assessed using a carrier test method against dormant spores, germinating spores and vegetative cells of C. difficile (NCTC 11204 and ribotype 027) over a 3 h period in the presence and absence of organic matter. RESULTS: Copper metal eliminated all vegetative cells of C. difficile within 30 min, compared with stainless steel which demonstrated no antimicrobial activity (P < 0.05). Copper significantly reduced the viability of spores of C. difficile exposed to the germinant (sodium taurocholate) in aerobic conditions within 60 min (P < 0.05) while achieving a >or=2.5 log reduction (99.8% reduction) at 3 h. Organic material did not reduce the antimicrobial efficacy of the copper surface (P > 0.05). CONCLUSIONS: The use of copper surfaces within the clinical environment and application of a germination solution in infection control procedures may offer a novel way forward in eliminating C. difficile from contaminated surfaces and reducing CDAD.

Antimicrobial efficacy of chlorhexidine digluconate alone and in combination with eucalyptus oil, tea tree oil and thymol against planktonic and biofilm cultures of Staphylococcus epidermidis.

OBJECTIVES: Effective skin antisepsis and disinfection of medical devices are key factors in preventing many healthcare-acquired infections associated with skin microorganisms, particularly Staphylococcus epidermidis. The aim of this study was to investigate the antimicrobial efficacy of chlorhexidine digluconate (CHG), a widely used antiseptic in clinical practice, alone and in combination with tea tree oil (TTO), eucalyptus oil (EO) and thymol against planktonic and biofilm cultures of S. epidermidis. METHODS: Antimicrobial susceptibility assays against S. epidermidis in a suspension and in a biofilm mode of growth were performed with broth microdilution and ATP bioluminescence methods, respectively. Synergy of antimicrobial agents was evaluated with the chequerboard method. RESULTS: CHG exhibited antimicrobial activity against S. epidermidis in both suspension and biofilm (MIC 2-8 mg/L). Of the essential oils thymol exhibited the greatest antimicrobial efficacy (0.5-4 g/L) against S. epidermidis in suspension and biofilm followed by TTO (2-16 g/L) and EO (4-64 g/L). MICs of CHG and EO were reduced against S. epidermidis biofilm when in combination (MIC of 8 reduced to 0.25-1 mg/L and MIC of 32-64 reduced to 4 g/L for CHG and EO, respectively). Furthermore, the combination of EO with CHG demonstrated synergistic activity against S. epidermidis biofilm with a fractional inhibitory concentration index of <0.5. CONCLUSIONS: The results from this study suggest that there may be a role for essential oils, in particular EO, for improved skin antisepsis when combined with CHG.

Reduced adhesion formation following laparoscopic versus open colorectal surgery.

BACKGROUND: Adhesion formation is common after abdominal surgery. This study aimed to compare the extent of adhesion formation following laparoscopic and open colorectal surgery. METHODS: An observational study was undertaken to identify adhesions in patients undergoing laparoscopy after previous laparoscopic or open colectomy. Adhesions were scored according to a system validated for interobserver (median kappa = 0.80) and intraobserver (kappa = 0.82) agreement. The primary endpoint was the overall adhesion score (0-10); a secondary endpoint was the adhesion score at the main incision site (0-6). RESULTS: Forty-six patients were recruited (13 laparoscopic and 33 open colectomy). In most patients (n = 29), laparoscopy was performed for tumour staging before liver resection. The median (interquartile range) overall adhesion score was 7 (5-8) in the open group and 0 (0-3) in the laparoscopic group (P < 0.001). A similar difference was found for the main incision score: 6 (4-6) versus 0 (0-0) (P < 0.001). CONCLUSION: There may be a reduction in adhesion formation following laparoscopic compared with open colectomy, although the small sample size limits this conclusion.

Epidemiology of community-acquired meticillin-resistant Staphylococcus aureus obtained from the UK West Midlands region.

SUMMARY: Between January 2005 and December 2005, 199 meticillin-resistant Staphylococcus aureus (MRSA) isolates were obtained from non-hospitalised patients presenting skin and soft tissue infections to local general practitioners. The study area incorporated 57 surgeries from three Primary Care Trusts in the Lichfield, Tamworth, Burntwood, North and East Birmingham regions of Central England, UK. Following antibiotic susceptibility testing, pulsed-field gel electrophoresis, Panton-Valentine leukocidin gene detection and SCCmec element assignment, 95% of the isolates were shown to be related to hospital epidemic strains EMRSA-15 and EMRSA-16. In total 87% of the isolate population harboured SCCmec IV, 9% had SCCmec II and 4% were identified as carrying novel SCCmec IIIa(-mecI). When mapped to patient home postcode, a diverse distribution of isolates harbouring SCCmec II and SCCmec IV was observed; however, the majority of isolates harbouring SCCmec IIIa(-mecI) were from patients residing in the north-west of the study region, highlighting a possible localised clonal group. Transmission of MRSA from the hospital setting into the surrounding community population, as demonstrated by this study, warrants the need for targeted patient screening and decolonisation in both the clinical and community environments.

Physical and chemical factors influencing the germination of Clostridium difficile spores.

AIMS: To investigate the influence of chemical and physical factors on the rate and extent of germination of Clostridium difficile spores. METHODS AND RESULTS: Germination of C. difficile spores following exposure to chemical and physical germinants was measured by loss of either heat or ethanol resistance. Sodium taurocholate and chenodeoxycholate initiated germination together with thioglycollate medium at concentrations of 0.1-100 mmol l(-1) and 10-100 mmol l(-1) respectively. Glycine (0.2% w/v) was a co-factor required for germination with sodium taurocholate. There was no significant difference in the rate of germination of C. difficile spores in aerobic and anaerobic conditions (P > 0.05) however, the initial rate of germination was significantly increased at 37 degrees C compared to 20 degrees C (P < 0.05). The optimum pH range for germination was 6.5-7.5, with a decreased rate and extent of germination occurring at pH 5.5 and 8.5. CONCLUSIONS: This study demonstrates that sodium taurocholate and chenodeoxycholate initiate germination of C. difficile spores and is concentration dependant. Temperature and pH influence the rate and extent of germination. SIGNIFICANCE AND IMPACT OF THE STUDY: This manuscript enhances the knowledge of the factors influencing the germination of C. difficile spores. This may be applied to the development of potential novel strategies for the prevention of C. difficile infection.

Sporicidal activity of two disinfectants against Clostridium difficile spores.

The sporicidal activity of an odour-free peracetic acid-based disinfectant (Wofasteril) and a widely-used dichloroisocyanurate preparation (Chlor-clean) was assessed against spores of the hyper-virulent strain of Clostridium difficile (ribotype 027), in the presence and absence of organic matter. In environmentally clean conditions, dichloroisocyanurate achieved a >3 log10 reduction in 3 minutes, but a minimum contact time of 9 minutes was required to reduce the viable spore load to below detection levels. Peracetic acid achieved a >3 log10 reduction in 30 minutes and was overall significantly less effective (P<0.05). However, in the presence of organic matter - which reflects the true clinical environment - there was no significant difference between the sporicidal activity of dichloroisocyanurate and peracetic acid over a 60-minute period (P=0.188). Given the greater occupational health hazards generally associated with chlorine-releasing agents, odour-free peracetic acid-based disinfectants may offer a suitable alternative for environmental disinfection.

Centralisation for resection of the pancreatic head: A comparison of operative factors and early outcomes during the evolving unit and tertiary unit phases at a UK institution.

AIMS: To assess impact of centralisation on patients undergoing pancreatic head resections at a tertiary hepatobiliary (HPB) centre in the UK. METHODS: Data were analysed from a prospectively maintained database from 1998 to 2014 on all patients undergoing pancreatic head resections. Two specific time periods were defined; these were the evolving unit phase (EU) from 1998 to 2009 and finally the established tertiary unit phase (TU) from 2010 to 2014. Peri-operative factors and post-operative outcomes were analysed. RESULTS: 395 resections were undertaken during the study period. Following establishment of our tertiary HPB unit, the volume of resections undertaken increased greater than three-fold with an associated increase in case-complexity (p = 0.004). Operating time was found to increase in the TU phase compared with EU phase (p=>0.0005) whilst there was no significant difference in the rate of peri-operative transfusion, or in post-operative morbidity rates. There was a significant reduction in the post-operative length of stay in the TU phase (p = 0.003) with a significantly higher proportion of patients being discharged within 9 days of their procedure (p=<0.0005). There was also a significant reduction in 30-day post-operative mortality in the TU phase (0.5%) compared with the EU phase (3%) (p = 0.029). CONCLUSIONS: Data from our series of 395 cases suggests that centralisation of pancreatic cancer services to a tertiary centre does result in improved patient outcomes. The benefits of a multi-disciplinary and specialist HPB service results in a high volume, high quality unit with improved patient outcomes.

A prospective clinical trial to evaluate the microbial barrier of a needleless connector.

Needleless connectors are being increasingly used for direct access to intravascular catheters. However, the potential for microbial contamination of these devices and subsequent infection risk is still widely debated. In this study the microbial contamination rate associated with three-way stopcock luers with standard caps attached was compared to those with Y-type extension set luers with Clearlink needleless connectors attached. Fifty patients undergoing cardiothoracic surgery who required a central venous catheter (CVC) as part of their peri- and postoperative management were studied for microbial contamination of CVC luers following 72 hrs in situ. Each patient's CVC was randomly designated to have either the three-way stopcocks with caps (control patients) or Clearlink Y-type extension sets (test patients). Prior to, and following each manipulation of the three-way stopcock luers or Clearlink devices, a 70% (v/v) isopropyl alcohol swab was used for disinfection of the connections. The microbial contamination of 393 luers, 200 with standard caps and 193 with Clearlink attached, was determined. The internal surfaces of 20 of 200 (10%) three-way stopcock luers with standard caps were contaminated with micro-organisms whereas only one of 193 (0.5%) luers with Clearlink attached was contaminated (P<0.0001). These results demonstrate that the use of the Clearlink device with a dedicated disinfection regimen reduces the internal microbial contamination rate of CVC luers compared with standard caps. The use of such needle-free devices may therefore reduce the intraluminal risk of catheter-related bloodstream infection and thereby supplement current preventive guidelines.

Infection risk associated with a closed luer access device.

The potential for microbial contamination associated with a recently developed needleless closed luer access device (CLAD) (Q-Syte; Becton Dickinson, Sandy, UT, USA) was evaluated in vitro. Compression seals of 50 multiply activated Q-Syte devices were inoculated with Staphylococcus epidermidis NCTC 9865 in 25% (v/v) human blood and then disinfected with 70% (v/v) isopropyl alcohol followed by flushing with 0.9% (w/v) sterile saline. Forty-eight of 50 (96%) saline flushes passed through devices that had been activated up to a maximum of 70 times remained sterile. A further 25 Q-Syte CLADs that had undergone multiple activations were challenged with prefilled 0.9% (w/v) sterile saline syringes, the external luer tips of which had been inoculated with S. epidermidis NCTC 9865 prior to accessing the devices. None of the devices that had been accessed up to 70 times allowed passage of micro-organisms, despite challenge micro-organisms being detected on both the syringe tip after activation and the compression seals before decontamination. These findings suggest that the Q-Syte CLAD may be activated up to 70 times with no increased risk of microbial contamination within the fluid pathway. The device may also offer protection from the external surface of syringe tips contaminated with micro-organisms.