Evaluation of disinfection of flexible nasendoscopes using Tristel wipes: a prospective single blind study

INTRODUCTION

The otorhinoiaryngoiogy department at Northwick Park Hospital uses the Tristei wipes system for cleaning nasendoscopes in the outpatient clinics. This system uses chlorine dioxide as its only disinfectant. The manufacturer claims the system provides safe sterilisation of nasendoscopes. However, there appear to be no reports in the literature to date that evaluate the efficacy of this system in a clinical setting. The aim of this study was to evaluate the ‘in use’ efficacy of Tristei wipes in decontaminating nasendoscopes and to identify any significant contamination between cleaning and usage.

METHODS

A total of 31 cleaning episodes were performed. Each cleaning episode included two swabs after cleaning the scopes, one from the tip and the other from the handle. Another two swabs from the same areas were also taken before application to the patient. The microbiology unit evaluated all swabs for bacterial, fungal and mycobacterial growth.

RESULTS

Overall, 123 swabs from 31 cleaning episodes were tested. None of the swabs taken from the tips (n=31) or handles (n=31) after cleaning with Tristei wipes developed any organism growth. Furthermore, none of the swabs taken from the tip of the scopes before using on patients (n=31) developed any growth. Of the 31 swabs taken from the handle before use, 3 developed significant staphylococcal growth.

CONCLUSIONS

In our study, the ‘in use’ efficacy of Tristei wipes in cleaning the scopes of bacteria, fungi and mycobacteria was 100%. Attention to hand hygiene and the use of gloves should be considered when handling the cleaned scopes to minimise the risk of contamination between cleaning and application to patients.     

喉镜柄所致院内感染：对现行指南的置疑

背景按照现有规定，不同病例之间喉镜片是进行清洁的。然而，尽管有证据显示喉镜柄可能导致院内感染，但各个机构以及美国麻醉医师协会却都没有任何针对喉镜柄消毒的指导意见。我们假设，喉镜柄极易被细菌和病毒污染，并对新型的清洁喉镜柄方法的应用加以证实。方法从成人手术间取60个喉镜柄，用无菌拭子取样。采样在两个手术之间进行，手术间是用于多专科手术的，房间和设备已为下一个手术常规清洁后再收集样本。其中40支喉镜柄要去做需氧菌培养，分离的菌株同时做抗生素耐药检测。另外20支喉镜柄要通过聚合酶链式反应检测17种呼吸道病毒。结果4JD支送检细菌培养的喉镜柄样本显示，30（75％）支喉镜柄的细菌污染检测呈阳性，在阳性结果中，25（62．5％）支喉镜柄是被产生凝固酶阴性葡萄球菌污染，7（17．5％）支喉镜柄是被非炭疽的芽孢杆菌属的细菌污染，3（7．5％）支喉镜柄是被α-溶血性链球菌属的细菌污染，1（2．5％）支喉镜柄是被肠球菌、金黄色葡萄球菌（金葡菌）和棒状杆菌属所污染。这其中没有发现耐万古霉素的肠球菌、耐甲氧西林的金葡菌以及格兰阴性杆菌。所有病毒的检测都是阴性的。结论我们发现，喉镜柄经低标准消毒后仍有较高的细菌污染发生率。然而这其中没有发现耐万古霉素的肠球菌、耐甲氧西林的金葡菌、格兰阴性杆菌或是呼吸道病毒。因此，我们的结果支持采纳如下的指导意见：在每一例患者使用后，对喉镜柄应强制性的进行至少低标准的消毒处理。     

Microbial contamination assessment of cryostored autogenous cranial bone flaps: should bone biopsies or swabs be performed?

Background

Autogenous cranioplasty infection requiring bone flap removal is under-recognised as a major complication causing significant morbidity. Microbial contamination of stored bone flaps may be a significant contributing factor. Current infection control practices and storage procedures vary. It is not known whether ‘superficial’ swabs or bone cultures provide a more accurate assessment.

Method

Twenty-five skull flaps that were cryo-stored for more than 6 months were studied. Two swab samples (superficial and deep) and a bone biopsy sample were taken from each skull flap sample and cultured. Half blood agar and half chocolate agar plates were inoculated with the swabs for anaerobic and aerobic cultures respectively. The bone biopsy samples were cultured in brain-heart broth and subcultured similar to the swabs for 5 days.

Results

Incidence of microbial contamination was 20 % in the bone flaps studied. One swab culture and five bone biopsy cultures were positive for bacterial growth, all of which contained Propionibacterium acnes (p?=?0.014). Positive cultures were from bone flaps stored less than 18 months, whereas no growth was obtained from bone flaps that were stored longer (p?=?0.014).

Conclusions

Bone biopsy culture is a more sensitive technique of assessing microbial contamination of cryo-stored autogenous bone flaps than swab cultures. The clinical implications of in vitro demonstration of microbial contamination require further study.     

In Vivo Analysis of the Morphologic Characteristics of Synthetic Mesh to Resist MRSA Adherence

Background

Synthetic mesh has significantly reduced recurrence rates for ventral hernia repair; however, prosthetic mesh infections remain a significant complication. We hypothesized that unique mesh constructs might alter the ability of various synthetic meshes to clear bacterial contamination. To evaluate this, we studied commercially available synthetic meshes ability to clear a bacterial contamination with methicillin resistant Staphylococcus aureus infection.

Methods

Two hundred and eighty-three rats underwent hernia repair with one of nine synthetic materials. Control animals were closed, and the remainder was inoculated with either 10⁴ or 10⁶ methicillin-resistant S. aureus (MRSA). Animals were survived for 30?days without systemic antibiotics. At necropsy, the mesh was harvested and quantitative cultures and bacterial clearance assessed.

Results

All clean repairs remained sterile. Rates of bacterial clearance for 10⁴ repairs revealed that unprotected monofilament materials cleared significantly more bacteria than composite meshes and multifilament meshes (p?=?<0.01 and p?=?0.01, respectively). At higher levels of bacterial contamination (10⁶), all materials had a reduction in bacterial clearance, although monofilament materials had higher bacterial clearance compared to composite meshes (p?=?0.03).

Conclusions

Monofilament unprotected polypropylene and polyester mesh can clear a large percentage of MRSA contaminants. Multifilament, composite anti-adhesive barrier meshes, and laminar antimicrobial impregnated mesh are not able to clear bacterial contamination with MRSA. Unique properties of synthetic material should be considered when evaluating a prosthetic for high-risk incisional hernia repair.     

Surgical Helmets Used During Total Joint Arthroplasty Harbor Common Pathogens: A Cautionary Note

BackgroundThe use of personal-protection surgical helmet/hood systems is now a part of the standard surgical attire during arthroplasty in North America. There are no protocols for the disinfection of these helmets.MethodsThis is a prospective, single-center, observational study. Helmets worn by 44 members of the surgical team and foreheads of 44 corresponding surgical personnel were swabbed at three distinct time points. In addition, 16 helmets were treated with hypochlorite spray to determine if pathogens could be eliminated. Swabs obtained were processed for culture and next-generation sequencing (NGS).ResultsOf the 132 helmet samples, 97 (73%) yielded bacteria on culture and 94 (71%) had evidence of bacterial–deoxyribonucleic acid (DNA) on NGS. Of the swabs sent for bacterial identification at the three time points, at least one from each helmet was positive for a pathogen(s). Of the 132 forehead samples, 124 (93%) yielded bacteria on culture and 103 (78%) had evidence of bacterial-DNA on NGS. The most commonly identified organism from helmets was Cutibacterium acnes (86/132) on NGS and Staphylococcus epidermidis (47/132) on culture. The most commonly identified organism from the foreheads of surgical personnel was Cutibacterium acnes (100/132) on NGS and Staphylococcus epidermidis (70/132) on culture. Sanitization of helmets was totally effective; no swabs taken the following morning for culture and NGS identified any bacteria.ConclusionThis study demonstrates that surgical helmets worn during orthopedic procedures are contaminated with common pathogens that can potentially cause surgical site infections. The findings of this study should at the minimum compel us to develop protocols for the disinfection of these helmets.     

Baby bottle steam sterilizers disinfect home nebulizers inoculated with bacterial respiratory pathogens

BackgroundContaminated nebulizers are a potential source of bacterial infection but no single method is universally accepted for disinfection. We hypothesized that baby-bottle steam sterilizers effectively disinfect home nebulizers.MethodsHome nebulizers were inoculated with the common CF respiratory pathogens methicillin resistant Staphylococcus aureus, Burkholderia cepacia, Haemophilus influenzae, mucoid and non mucoid Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. The nebulizers were swabbed for bacterial growth, treated with either the AVENT (Philips), the NUK Quick & Ready (Gerber) or DRY-POD (Camera Baby) baby bottle steam sterilizer and reswabbed for bacterial growth.ResultsAll steam sterilizers were effective at disinfecting all home nebulizers. Viable bacteria were not recovered from any inoculated site after steam treatment, under any conditions tested.ConclusionsSteam treatment is an effective disinfection method. Additional studies are needed to confirm whether these results are applicable to the clinical setting.     

Effect of an infection control educational programme on anaesthetists’ attitude and anaesthetic field bacterial contamination

ObjectivesTo evaluate the impact of an infection control educational programme in anaesthetic practice on the clinical performance of the personnel working in anaesthetic field and anaesthetic work place bacterial contamination.MethodsThis study was conducting on 35 personnel involved in 500 operations over two and half months. Their compliance towards handling of anaesthetic equipments, wearing of protective tools and hand hygiene was evaluated using a 13 items check list pre and post delivering of an educational infection control programme (intervention). Of 500 operations 300 were randomly selected for evaluation of bacterial contamination. Two swabs were taken from anaesthetic place before induction of general anaesthesia (T0) and 30 min intraoperative (T1) pre and post intervention. Another swab was taking from anaesthetists’ hands 15 min after induction of anaesthesia (T2).ResultsThe intervention programme influenced positively the attitude of junior anaesthetists and nurses regarding the proper use of protective tools, anaesthetic equipments and hand hygiene. Senior anaesthestists’ compliance with hand hygiene, frequency use of gloves and anaesthetic filter did not change after intervention. But their attitude towards handling of laryngoscope, anaesthetic face mask and catheter for suction improved after intervention. The adherence of housekeepers to hand hygiene, frequency of gloves use and anaesthetic equipments’ disinfection improved significantly after intervention. Ninety-two (63%) swabs were positive for bacteria at T0 before intervention. They reduced to 9 (6.3%) positive swabs after intervention. The number of positive swabs at T1 was 121 (82.9%) before intervention, reduced to 68 (47.2%) after intervention. One hundred and eight (74%) swabs from hands of anaesthetists were positive for bacteria before intervention. They lowered significantly to 55 (38.2%) after intervention. Bacterial cross infection between anaesthetic machine and anaesthetists’ hands existed pre and post intervention. In conclusion, infection control programme enhanced personnel clinical compliance and reduced bacterial contamination in anaesthetic place.     

Metagenome – Inferred bacterial replication rates in cystic fibrosis airways

Bacterial replication rates were determined from metagenome sequencing of nasal lavage, throat swabs and induced sputa collected from healthy subjects and individuals with COPD or cystic fibrosis. More than 90% of peak-to-trough coverage ratios of major clones were above 1.4 indicating that the most abundant bacterial species in the microbial communities were replicating in the airways including common inhabitants such as Prevotella and Streptococcus species as well as the cystic fibrosis pathogens Staphylococcus aureus and Pseudomonas aeruginosa. The populations of P. aeruginosa and S. aureus were replicating their pool of chromosomes more slowly than the populations of the common inhabitants of a healthy airway microbial flora. The assessment of growth dynamics in microbial metagenomes could become a decision-making tool for the diagnosis and management of bacterial infections in cystic fibrosis.     

Cleaning,disinfection and sterilization of equipment

Decontamination is a combination of processes, in which pathogens are removed, inactivated or destroyed, to render a reusable item safe for further use. It comprises cleaning and either disinfection or sterilization as appropriate. Cleaning physically removes infectious agents and the organic matter on which they thrive, but does not necessarily destroy them. Disinfection is a process of inactivating pathogenic organisms except for bacterial spores. Sterilization is the elimination of all viable microorganisms. Single-use medical devices resolve the difficulties of reuse and decontamination procedures and should be used where appropriate. Healthcare-associated infections place a serious burden on the NHS and healthcare organizations have a legal responsibility to implement changes to reduce infections. An effective infection control system relies on the whole of an organization and not just those areas processing equipment. The MAC Manual, developed by the Medicines and Healthcare Products Regulatory Agency provides guidance on sterilization, disinfection and cleaning of medical equipment in the health service.     

The effect of presence of facultative bacteria species on semen and sperm quality of men seeking fertility care

IntroductionInfections of male urogenital tracts may contribute to male infertility. However, the effects of bacterial presence on sperm quality and fertility are controversial.ObjectivesWe investigated the occurrence of non-specific bacteria and quality/quantity of semen of infertile and fertile control groups in Nigeria.Subjects and methodsWe investigated 162 infertile and 54 fertile men. Spermiogram, culture, bacterial isolation and characterization were conducted.ResultsWe report 114/162(70.4%) occurrence of bacteria species, 49.4% of such were Gram positive and 21% Gram negative: Staphylococcus aureus (29.6%) and Escherichia coli (10.5%) had the highest occurrence for each group respectively. On semen quality/quantity, we report 14.2% azoospermia, 52.5% oligozoospermia and 33.3% of normozoospermia. The mean sperm concentrations were 10 × 7/ml and 41 × 10 6/ml for oligo and normozoospermia respectively. Majority (52%) of azoospermic group had no bacterial growth. S. aureus was the most implicated among the bacterial positive group. Within the ologozoospermic category, 28% had no bacterial growth, 28% had S. aureus and 11.8% E. coli. The normozoospermic patients had 18.5% no bacteria contamination, 33.3% had S. aureus, 13% had E. coli. From the analysis, the normozoospermic group with bacterial contamination had lower sperm concentrations compared with those without contamination. It was apparent that factors other than bacterial contamination may contribute more to oligozoospermia (compare: “no bacteria” group mean sperm concentration 8.97 × 106/ml, Gram positive bacteria contaminated group 17.74 × 106/ml and Gram negative bacteria contaminated group 13.66 × 106/ml). The mean progressive motility ratios were lower (15.6 [a]% + 18.3 [b]%) = 33.9%) against WHO standard (a + b = >50%) and control RPM (a) = 55.3%. Generally, the semen quality (vol., rapid progressive motility, sperm concentration and immotility) were significantly lower than the fertile group, P = 0.0005, <0.0001, <0001 and 0.0335, respectively.ConclusionsAlthough bacterial presence in semen reduced mean sperm concentration and viability, thereby contributed to oligozoospermia and by extension the chances of siring a child, however, factors other than bacterial presence may contribute more. Improved interpretative approaches of semen analyses are highlighted.     

Comparison of the resistance to infection of intestinal submucosa arterial autografts versus polytetrafluoroethylene arterial prostheses in a dog model

Purpose: Prosthetic graft infection represents a most challenging complication to the vascular surgeon. Although expanded polytetrafluoroethylene (ePTFE) grafts have an acceptable patency rate, especially in the large-diameter arterial location, bacterial contamination of this material usually requires surgical removal of the graft.Methods: We compared the resistance of large-diameter ePTFE grafts and grafts constructed of small intestinal submucosa (SIS) to deliberate infection with Staphylococcus aureus. Eighteen dogs were divided into two equal groups, and the infrarenal aorta was replaced with either ePTFE or SIS graft material. One hundred million S. aureus organisms were deposited directly on the graft at the time of surgery, and the dogs were observed for 30 days.Results: One dog with an ePTFE graft died of hemorrhage from an anastomosis site at 21 days. Of the remaining eight dogs with ePTFE grafts, four had positive culture results from the removed graft material, and all had histologic evidence for persistent infection. These dogs also had chronic fever, and the average white blood cell count at day 30 was 15,600/mm³. All nine dogs with SIS grafts had patent grafts, were afebrile after the first week, had an average white blood cell count of 11,500/mm³ at 30 days (p value = NS), had negative culture results, and had the histologic appearance of graft remodeling with collagen that was free of active inflammation.Conclusions: We conclude that large-diameter arterial SIS grafts are more resistant to persistent infection with S. aureus than ePTFE grafts in this dog model of deliberate bacterial inoculation. (J VASC SURG 1994;19:465-72.)     

Povidone Iodine and Skin Disinfection before Initiation of Epidural Anesthesia

Background: Povidone iodine (PI) solution is used commonly for skin disinfection before epidural and spinal anesthesia. Although there have been reports indicating the presence of microbial contaminants in PI solution, none have evaluated the prevalence of PI contamination. The aims of this study were to assess the frequency of bacterial contamination of previously opened bottles of PI solution and to compare the effectiveness of new and previously opened bottles of PI solution for skin disinfection.

Methods: Twenty previously opened and ten previously unopened multiple-use bottles of PI solution were evaluated for microbial contamination. In addition, final swabs and PI solution used for skin disinfection in 80 patients undergoing elective epidural analgesia were evaluated.

Results: The inside of the bottle cap or the PI solution from 40% of the multiple-use PI bottles in use were contaminated. There was no growth from any previously unused PI bottles. Povidone iodine from newly opened bottles provided more effective skin decontamination than did solution from previously opened bottles.     

A prospective study of methicillin-resistant Staphylococcus aureus colonization in children scheduled for elective surgery

Background

Staphylococcus aureus is a major cause of surgical wound infections. To obtain contemporary data on S aureus, we performed a prospective study of colonization and infection in children scheduled for elective surgical procedures.

Methods

A nasal swab and clinical information were obtained at the presurgical outpatient visit. At operation, nasal and perianal swabs were obtained. S aureus were isolated and characterized.

Results

We enrolled 499 patients from June 2005 to April 2007. Wound classes were 1 (73%), 2 (22%), 3 (5%), and 4 (0.2%). Prophylactic antibiotics were administered for 153 (31%). Postoperative length of stay ranged from 0 (77%) to 6 days, with 19 (4%) staying 4 days or more. Screening cultures grew S aureus for 186 procedures (36.6%); of these, 141 were methicillin-resistant S aureus (MRSA) (76% of all staphylococcal cultures or 28% of all procedures). Most MRSA had Staphylococcal Chromosomal Cassette mec type II and resistance to clindamycin—typical for hospital-associated strains. There were 10 (2%) surgical site infections, including 4 methicillin-sensitive S aureus, 1 MRSA, 2 with no growth, and 2 with no cultures.

Conclusion

Methicillin-resistant S aureus colonization was common in asymptomatic children. Most strains appeared to be health care-associated and resistant to clindamycin. Wound infection rate remained low despite the high prevalence of staphylococcal colonization.     

Bacterial adhesion to braided surgical sutures: an in vitro study

Background

Surgical suture materials are accepted to be associated with a substantial proportion of surgical site infections. These infections are related with biofilm formation similar to that of other synthetic and implantable medical devices.

Methods

We conducted an in vitro study to investigate the bacterial adherence to different types of braided surgical sutures. The included sutures were polyglactin (Vicryl®) group (VG), rapidly absorbable polyglactin (Rapide-Vicryl®) group (RVG), nitrofurazone-coated polyglactin (Vicryl®) group (FVG), polyethylene terephthalate (Etibond®) group (EG), and natural silk (Silk®) group (SG). All sutures were cut in 1 cm length, embedded into tryptic soy broth, and then 10⁶-CFU/ml Escherichia coli and Staphylococcus aureus were added. After the 24th and 96th hour of incubation, bacterial colonies were counted, and results were expressed as CFU/cm.

Results

E.coli adhesion was significantly lower in VG and significantly higher in SG compared to FVG, RVG, and EG at the 24th and 96th hour of cultivation (p?<?0.05). The S.aureus adhesion results at 24th hour showed that VG had the least bacterial adhesion, and FVG had the most bacterial adhesion compared to other sutures (p?<?0.05). The S.aureus adhesion results at the 96th hour of cultivation showed that bacterial adhesion on sutures was not significantly different between groups (p?>?0.05).

Conclusion

Of all braided surgical sutures, bacterial adhesion is significantly lower in polyglactin and significantly higher in silk sutures. Nitrofurazone coverage of suture worsens S.aureus contamination of the suture.Level of Evidence: Not ratable

     

Use of light handles in the laminar flow operating theatre--is it a cause of bacterial concern?

Airborne bacteria introduced during routine joint replacement surgery are known to be an important source of joint sepsis with disastrous results. Recently, Robinson et al. [Robinson AHN, Bentley G, Drew S, Anderson J, Ridgway GL. Suction tip contamination in the ultraclean air operating theatre. Ann R Coll Surg Engl 1993; 75: 254-6] have demonstrated that the conventional surgical sucker forms a focus for airborne pathogens which results in septic loosening of hip prostheses. Similarly, the potential contamination of theatre light handles, commonly used during total hip and knee replacements, gives cause for concern. To assess if there was any evidence of contamination, we cultured bacterial swabs taken from the light handles before and after 15 such procedures, all of which were held in a conventional orthopaedic operating theatre. Fortunately, our study found no reason to stop the use of light handles in joint replacement operations.     

Bacterial adherence to vascular prostheses: A determinant of graft infectivity

An in vitro model was developed to quantitatively measure bacterial adherence to the surface of prosthetic vascular graft material. Four strains of bacteria (Staphylococcus aureus, nonmucin-producing S. epidermidis [SP-2], mucin-producing S. epidermidis [RP-12], and Escherichia coli) were used to inoculate expanded polytetrafluoroethylene (ePTFE), woven Dacron, and velour knitted Dacron graft material. After graft specimens were incubated in a 10⁷ suspension of bacteria, they were washed to remove nonadherent organisms and ultrasonically oscillated to dislodge adherent organisms. Quantitative culture of the sonication effluent was used to calculate bacterial adherence, expressed as the number of colony-forming units found in each square centimeter of graft material per 10⁷ inoculum. All bacterial strains had a greater affinity to velour knitted Dacron graft than to ePTFE (p < 0.025). E. coli and S. aureus adhered to velour knitted Dacron in greater numbers than to woven Dacron (p < 0.04). The production of extracellular polysaccharide (mucin) by the RP-12 strain significantly increased adherence to both ePTFE and Dacron grafts compared with the other three bacterial strains tested (p < 0.04). Although E. coli was less adherent to ePTFE than nonmucin-producing staphylococcal strains (S. aureus and SP-2), no difference in adherence to knitted or woven Dacron graft material was demonstrated. The differential adherence of bacteria to prosthetic vascular grafts pays an important role in the pathogenesis of graft sepsis and determines relative graft infectivity. The in vitro model developed is well suited for further study of the mechanisms by which bacteria adhere to and colonize vascular grafts. (J VASC SURG 1986;3:732-40.)     

Adherence of Staphylococcus aureus isolated in peritoneal dialysis-related exit-site infections to HEp-2 cells and silicone peritoneal catheter materials

Background. Peritoneal catheter exit-site infections cause a relevant morbidity in peritoneal dialysis patients and are frequently caused by Staphylococcus aureus. We tested the hypothesis that adherence of exit-site-derived S.aureus to epithelial cells and peritoneal catheter silicone tubes discriminates virulent and less virulent strains. Methods. The binding of isolated S. aureus to an epithelial cell line (HEp-2) and to silicone tubes was analyzed using light-microscopy or radioactive labeling of bacteria. Results. Of 378 exit-site swabs, 99% (26%) were positive for microbial growth. S. aureus was cultured in 25 of 99 positive swabs; three of 13 swabs taken in exit-site infections grade 3 and 4 that had tested positive for S. aureus. Adherence of S. aureus from exit-site infections grade 2, 3 and 4 to Hep-2 cells did not differ from adherence of bacteria isolated from asymptomatic or moderately inflamed catheter exit sites (grade 0-2). However, binding of S. aureus to silicone tubes was enhanced in grade 0/1 compared with grade 2-4 exit-site isolates. Conclusions. Staphylococcus aureus is an important pathogen in CAPD-related exit-site infection being isolated in about 6.6% of all exit-site swabs (and in 25% of all positive swabs). Silicone-adhesive strains may be of more clinical significance in peritoneal dialysis patients since adhesion to silicone was increased in S. aureus strains isolated in more severe exit-site infections.     

Povidone-Iodine–Based Solutions for Decolonization of Nasal Staphylococcus aureus: A Randomized,Prospective, Placebo-Controlled Study

Background

Nasal Staphylococcus aureus decolonization reduces the risk of surgical site infections after orthopedic procedures. Povidone-iodine (PI)-based solutions have shown promising results in bacteria decolonization. The unique physiology of the nose may pose challenges for the bioactivity profiles of PI solutions. This study compared the antibacterial efficacy of an off-the-shelf PI product with a specifically manufactured PI-based skin and nasal antiseptic (SNA).

Efficacy of spray disinfection with a 2-propanol and benzalkonium chloride containing solution before epidural catheter insertion--a prospective, randomized, clinical trial

Background. Skin disinfection before neuroaxial blockade proceduresis usually obtained with sterile swabs impregnated in disinfectant.Spray disinfection is also an option which is frequently usedin minor invasive procedures. The purpose of our study was tocompare the efficacy of conventional swab disinfection withspray disinfection prior to epidural catheterization. Methods. Seventy patients who requested epidural analgesia wererandomly selected. The first group (n=35) received disinfectionwith swabs (SW) containing 2-propanol and benzalkonium chloride.The other 35 patients received spray (SP) disinfection withthe same solution. Three microbiological cultures were obtained:one culture prior to skin disinfection, a second immediatelyafter disinfection and a third from the tip of the epiduralcatheter upon removal. Results. One patient in the SW group had a positive skin cultureimmediately after the disinfection with a very low number ofcolony forming units. The other skin culture specimens wereall sterile in both groups. The colonization rate of catheterswas not statistically different between the groups at removal. Conclusion. In this study, spray disinfection was equally efficaciouscompared with the conventional skin disinfectant technique.Our results support the routine use of this simple and cheapalternative method of skin disinfection before epidural anaesthesia.     

Foot and ankle injuries during the Athens 2004 Olympic Games

Background

The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound.

Methods

Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37°C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room.

Results

There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p < 0.001) increase in microbial counts post hydrodebridement. Levels ranging from 950 colony forming units per meter cubed (CFUs/m³) to 16780 CFUs/m³ were observed with active sampling of the air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m³. During removal of the wound dressing, a significant increase was observed relative to basal counts (p < 0.05). Microbial load of the air samples was still significantly raised 1 hour post-therapy.

Conclusion

The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.