The effects of peracetic acid solution on the treatment of otomycosis in an animal model: a new antifungal drug?

OBJECTIVE: This study aimed to investigate the therapeutic effects of 1 per cent and 0.01 per cent peracetic acid as an antifungal agent in animal otomycosis. METHOD: After creating a superficial scratch in the external auditory canal of guinea pigs, a suspension of Aspergillus niger, Aspergillus fumigatus and candida were inoculated into the ears of the animals. After otomycosis, the effect of 1 per cent or 0.01 per cent peracetic acid on otomycosis was evaluated by otomicroscopy and culture at 10 days post-treatment and compared with 2 per cent acetic acid as the control. RESULTS: A 10-day treatment with 1 per cent peracetic acid and 2 per cent acetic acid (control) showed normal otomicroscopy and negative cultures compared with 0.01 per cent peracetic acid. Drug sedimentation or other side effects in the external auditory canal or tympanic membrane were not observed during treatment with peracetic acid. CONCLUSION: The findings of this study confirm that the treatment of otomycosis with 1 per cent peracetic acid in an animal model is beneficial and may be a novel therapeutic treatment for otomycosis.

Scalable in-hospital decontamination of N95 filtering face-piece respirator with a peracetic acid room disinfection system.

BACKGROUND: Critical shortages of personal protective equipment, especially N95 respirators, during the coronavirus disease 2019 (COVID-19) pandemic continues to be a source of concern. Novel methods of N95 filtering face-piece respirator decontamination that can be scaled-up for in-hospital use can help address this concern and keep healthcare workers (HCWs) safe. METHODS: A multidisciplinary pragmatic study was conducted to evaluate the use of an ultrasonic room high-level disinfection system (HLDS) that generates aerosolized peracetic acid (PAA) and hydrogen peroxide for decontamination of large numbers of N95 respirators. A cycle duration that consistently achieved disinfection of N95 respirators (defined as ≥6 log10 reductions in bacteriophage MS2 and Geobacillus stearothermophilus spores inoculated onto respirators) was identified. The treated masks were assessed for changes to their hydrophobicity, material structure, strap elasticity, and filtration efficiency. PAA and hydrogen peroxide off-gassing from treated masks were also assessed. RESULTS: The PAA room HLDS was effective for disinfection of bacteriophage MS2 and G. stearothermophilus spores on respirators in a 2,447 cubic-foot (69.6 cubic-meter) room with an aerosol deployment time of 16 minutes and a dwell time of 32 minutes. The total cycle time was 1 hour and 16 minutes. After 5 treatment cycles, no adverse effects were detected on filtration efficiency, structural integrity, or strap elasticity. There was no detectable off-gassing of PAA and hydrogen peroxide from the treated masks at 20 and 60 minutes after the disinfection cycle, respectively. CONCLUSION: The PAA room disinfection system provides a rapidly scalable solution for in-hospital decontamination of large numbers of N95 respirators during the COVID-19 pandemic.

An evaluation of alternative methods for sanitizing hatching eggs.

Different sanitization methods were evaluated as alternatives to formaldehyde fumigation for the reduction of eggshell and yolk sac microbiological counts, improvement of eggshell quality, incubation parameters, and day-old chick quality. A total of 10,080 hatching eggs were collected from a 70-wk-old commercial broiler breeder flock and distributed in a completely randomized block design with seven treatments: fumigation with paraformaldehyde (5.03 g/m3/30 min), fumigation with ozone (5-15 ppm/30 min), ultraviolet light-C irradiation (8.09 mW/cm2; 120 s; UV-C), hydrogen peroxide spraying (3%; 0.69 mL/egg), peracetic acid spraying (0.3%; 0.69 mL/egg; PAA), water spraying (0.69 mL/egg; water control), and without disinfection (dry control-DC). Spraying eggs with PAA and UV-C significantly reduced aerobic bacteria plate counts compared to the DC group. In addition, eggs disinfected with PAA had lower Enterobacteriaceae counts than the DC and water control groups. Eggshell quality, incubation parameters, and microbiological counts for yolk sac did not differ (P > 0.05) among treatments. This study demonstrated the potential for the application of PAA and UV-C for eggshell disinfection instead of formaldehyde; however, an electronic microscopic evaluation of the eggshell is necessary to determine if these methods cause any damage to the cuticle.

Efetividade do ácido peracético na desinfecção rápida de cones de guta-percha e de Resilon expostos ao Enterococcus faecalis / Effectiveness of peracetic acid in rapid disinfection of gutta-percha and Resilon cones exposed to Enterococcus faecalis

Objetivo: o objetivo desse trabalho foi verificar a efetividade do ácido peracético a 2% na descontaminação rápida de cones de guta-percha e de Resilon, comparado ao hipoclorito de sódio e à clorexidina. Métodos: os cones de guta-percha e Resilon foram imersos por cinco minutos para contaminação em suspensão de Enterococcus faecalis, e divididos em grupos (n = 10): ácido peracético a 2% (um e três minutos); NaOCl a 5,25% (um e três minutos); clorexidina a 2% (um e três minutos). Após a realização dos protocolos em teste, os cones foram transferidos para tubos de ensaio contendo meio Enterococcosel® e, então, foram mantidos em estufa a 37º por 48 horas. Após o período de observação, os tubos foram avaliados e os que apresentam turvação do meio foram consideradas positivos. Resultados: os resultados demonstraram que o ácido peracético a 2% parece ser efetivo para a descontaminação de ambos os tipos de cone, de forma alternativa ao NaOCl a 5,25%, enquanto a clorexidina a 2% apresentou menor efetividade (p < 0,05). Conclusão: Ambas as soluções, ácido peracético a 2% e NaOCl a 5,25%, foram efetivas na descontaminação de cones de guta-percha ou de Resilon nos tempos testados.

Sterilizing elastomeric chains without losing mechanical properties. Is it possible?

OBJECTIVE: To investigate the effects of different sterilization/disinfection methods on the mechanical properties of orthodontic elastomeric chains. METHODS: Segments of elastomeric chains with 5 links each were sent for sterilization by cobalt 60 (Co60) (20 KGy) gamma ray technology. After the procedure, the elastomeric chains were contaminated with clinical samples of Streptococcus mutans. Subsequently, the elastomeric chains were submitted to sterilization/disinfection tests carried out by means of different methods, forming six study groups, as follows: Group 1 (control - without contamination), Group 2 (70°GL alcohol), Group 3 (autoclave), Group 4 (ultraviolet), Group 5 (peracetic acid) and Group 6 (glutaraldehyde). After sterilization/disinfection, the effectiveness of these methods, by Colony forming units per mL (CFU/mL), and the mechanical properties of the material were assessed. Student's t-test was used to assess the number of CFUs while ANOVA and Tukey's test were used to assess elastic strength. RESULTS: Ultraviolet treatment was not completely effective for sterilization. No loss of mechanical properties occurred with the use of the different sterilization methods (p > 0.05). CONCLUSION: Biological control of elastomeric chains does not affect their mechanical properties.

Sterilizing elastomeric chains without losing mechanical properties. Is it possible?

OBJECTIVE: To investigate the effects of different sterilization/disinfection methods on the mechanical properties of orthodontic elastomeric chains. METHODS: Segments of elastomeric chains with 5 links each were sent for sterilization by cobalt 60 (Co60) (20 KGy) gamma ray technology. After the procedure, the elastomeric chains were contaminated with clinical samples of Streptococcus mutans. Subsequently, the elastomeric chains were submitted to sterilization/disinfection tests carried out by means of different methods, forming six study groups, as follows: Group 1 (control - without contamination), Group 2 (70°GL alcohol), Group 3 (autoclave), Group 4 (ultraviolet), Group 5 (peracetic acid) and Group 6 (glutaraldehyde). After sterilization/disinfection, the effectiveness of these methods, by Colony forming units per mL (CFU/mL), and the mechanical properties of the material were assessed. Student's t-test was used to assess the number of CFUs while ANOVA and Tukey's test were used to assess elastic strength. RESULTS: Ultraviolet treatment was not completely effective for sterilization. No loss of mechanical properties occurred with the use of the different sterilization methods (p > 0.05). CONCLUSION: Biological control of elastomeric chains does not affect their mechanical properties. .

OBJETIVO: verificar os efeitos de diferentes métodos de esterilização/desinfecção nas propriedades mecânicas de elásticos ortodônticos em cadeia. MÉTODOS: segmentos de elástico em cadeia com 5 elos cada foram enviados para esterilização em radiação gama com cobalto 60 (20 KGy). Após esterilização, esses foram contaminados com amostras clínicas de Streptococcus mutans. Passado esse período, foram submetidos aos testes de esterilização/desinfecção por diferentes métodos, formando seis grupos de estudo, assim denominados: Grupo 1 (controle - sem ter sido contaminado), Grupo 2 (álcool 70°GL), Grupo 3 (autoclave), Grupo 4 (ultravioleta), Grupo 5 (ácido peracético) e Grupo 6 (glutaraldeído). Após esterilização/desinfecção, avaliou-se a efetividade desses métodos, por meio de contagem de unidades formadoras de colônias por mL (UFC/mL), e as propriedades mecânicas desses materiais. Utilizou-se o teste t de Student para avaliar o número de UFC, além do ANOVA e, posteriormente, do teste de Tukey para avaliação da força. RESULTADOS: verificou-se que o ultravioleta não obteve eficácia total quanto à esterilização. E não ocorreu perda das propriedades mecânicas dos elásticos, com os diferentes métodos de esterilização utilizados (p > 0,05). CONCLUSÃO: o controle biológico de elásticos em cadeia não interfere nas suas propriedades mecânicas. .

Efficiency of hydrogen peroxide in improving disinfection of ICU rooms.

INTRODUCTION: The primary objective of this study was to determine the efficiency of hydrogen peroxide (H2O2) techniques in disinfection of ICU rooms contaminated with multidrug-resistant organisms (MDRO) after patient discharge. Secondary objectives included comparison of the efficiency of a vaporizator (HPV, Bioquell) and an aerosolizer using H2O2, and peracetic acid (aHPP, Anios) in MDRO environmental disinfection, and assessment of toxicity of these techniques. METHODS: This prospective cross-over study was conducted in five medical and surgical ICUs located in one University hospital, during a 12-week period. Routine terminal cleaning was followed by H2O2 disinfection. A total of 24 environmental bacteriological samplings were collected per room, from eight frequently touched surfaces, at three time-points: after patient discharge (T0), after terminal cleaning (T1) and after H2O2 disinfection (T2). RESULTS: In total 182 rooms were studied, including 89 (49%) disinfected with aHPP and 93 (51%) with HPV. At T0, 15/182 (8%) rooms were contaminated with at least 1 MDRO (extended spectrum ß-lactamase-producing Gram-negative bacilli 50%, imipenem resistant Acinetobacter baumannii 29%, methicillin-resistant Staphylococcus aureus 17%, and Pseudomonas aeruginosa resistant to ceftazidime or imipenem 4%). Routine terminal cleaning reduced environmental bacterial load (P <0.001) without efficiency on MDRO (15/182 (8%) rooms at T0 versus 11/182 (6%) at T1; P = 0.371). H2O2 technologies were efficient for environmental MDRO decontamination (6% of rooms contaminated with MDRO at T1 versus 0.5% at T2, P = 0.004). Patient characteristics were similar in aHPP and HPV groups. No significant difference was found between aHPP and HPV regarding the rate of rooms contaminated with MDRO at T2 (P = 0.313). 42% of room occupants were MDRO carriers. The highest rate of rooms contaminated with MDRO was found in rooms where patients stayed for a longer period of time, and where a patient with MDRO was hospitalized. The residual concentration of H2O2 appears to be higher using aHPP, compared with HPV. CONCLUSIONS: H2O2 treatment is efficient in reducing MDRO contaminated rooms in the ICU. No significant difference was found between aHPP and HPV regarding their disinfection efficiency.

Evaluation of the cytotoxicity of elastomeric ligatures after sterilisation with 0.25% peracetic acid.

INTRODUCTION: Sterilisation using peracetic acid (PAA) has been advocated for orthodontic elastic bands. However, cane-loaded elastomeric ligatures can also become contaminated during processing, packaging, and manipulation before placement in the oral cavity and are therefore susceptible, and possible causes, of cross-contamination. AIM: To test the hypothesis that 0.25% peracetic acid (PAA), following the sterilisation of elastomers, influences the cytotoxicity of elastomeric ligatures on L929 cell lines. MATERIALS AND METHODS: Four hundred and eighty silver elastomeric ligatures were divided into 4 groups of 120 ligatures to produce, Group TP (latex natural, bulk pack, TP Orthodontics), Group M1 (Polyurethane, bulk pack, Morelli), Group M2 (Polyurethane, cane-loaded, Morelli) and Group U (Polyurethane, cane-loaded, Uniden). Of the 120 ligatures in each group, 100 were sterilised in 0.25% PAA at time intervals (N = 20) of 1 hour, 2 hours, 3 hours, 4 hours and 5 hours. The 20 remaining elastomeric ligatures in each group were not sterilised and served as controls. Cytotoxicity was assessed using L929 cell lines and a dye-uptake method. Analysis of variance (ANOVA), followed by the Tukey post hoc test (p < 0.05) determined statistical relevance. RESULTS: There was a significant difference between TP, Morelli and Uniden elastomerics (p < 0.05), but no difference between the two types of Morelli elastomerics at the 1 hour time interval. In addition, there was a significant difference between Group CC and the other groups assessed, except between Groups CC and TP at the 1 hour time interval. The non-sterilised elastomeric ligatures showed similar cell viability to that observed after 1 hour of standard sterilisation. CONCLUSION: PAA did not significantly influence the cytotoxicity of elastomeric ligatures after a sterilisation time of 1 hour and is therefore recommended for clinical use.

The acaricidal efficacy of peracetic acid and deltamethrin against the fowl tick, Argas persicus, infesting laying hens.

The fowl tick, Argas persicus (Oken), is of veterinary importance as a parasite of poultry and wild birds. The antitick efficacy, in vitro and in vivo, of peracetic acid (PAA) and deltamethrin (DMT) was tested separately against A. persicus through the dipping technique. PAA (0.5 %) was highly efficient against soft tick larvae (A. persicus), resulting in 100 % mortality after 2 min. The lethal concentrations LC(50) and LC(95) were 0.310 and 0.503 %, respectively. The lethal time values LT(50) and LT(95) were 5.34 and 40.00 min, respectively, after treatment with PAA (0.25 %). Two minutes after exposure to DMT, LC(50) and LC(95) values were 0.033 and 0.052 % (33.204 and 51.527 mg/L), respectively. The LT(50) and LT(95) values were 27.03 and 305.46 min, respectively, after treatment with 0.025 % DMT (25 mg/L). After dipping in PAA (0.5 %), the chickens did not show respiratory signs or inflammation on the eyes and/or skin. By contrast, temporary coughing, sneezing, and ocular inflammations without dermatitis were observed in chickens dipped in DMT (0.05 % or 50 mg /L). Seven days posttreatment (PT), the reduction in the percentages of A. persicus infesting laying hens were 99.15 and 63.42 % after dipping in PAA and DMT, respectively. However, complete elimination of the number of ticks occurred after 28 days PT with DMT. PAA inhibits molting effectively (28 %) when compared with that of DMT (52 %). Results indicated that PAA is a more potent and promising acaricide against A. persicus (in vitro and in vivo) than DMT.

The effect of peracetic acid on removing calcium hydroxide from the root canals.

INTRODUCTION: The goal of this study was to evaluate the efficiencies of different irrigation solutions in the removal of calcium hydroxide (CH). METHODS: Forty-eight maxillary central incisor teeth were used. Root canals were prepared with the ProTaper system (Dentsply Maillefer, Baillagues, Switzerland). Five milliliters 2% NaOCl, 5 mL 17% EDTA, and 10 mL saline were used for final irrigation. The canals were filled with CH paste. Specimens were randomly divided into 4 experimental groups (n = 10) according to irrigation protocols. Positive and negative control groups (n = 4) were used. Group 1 used 2.5 mL 17% EDTA, group 2 used 2.5 mL 2.5% NaOCl + 2.5 mL 17% EDTA, group 3 used 2.5 mL 1% peracetic acid (PAA), and group 4 used 2.5 mL 0.5% PAA. The specimens were evaluated with scanning electron microscope analysis and scored. Kruskal-Wallis and Student Newman-Keuls post hoc tests were used for statistical analysis. RESULTS: In the apical thirds, 1% PAA was superior to the other groups (P < .05); however, there were no significant differences among the other groups (P > .05). In the middle thirds, no significant differences were found among the groups (P > .05). In the coronal thirds, 1% PAA was superior to the other groups. There were significant differences among all the other groups (P < .05). CONCLUSIONS: According to the findings of the present study, 1% PAA could be recommended for the removal of CH from the root canals.

Avaliação anti-microbiológica do ácido peracético como desinfetante para moldes odontológicos / Anti-microbial evaluation of peracetic acid as a disinfectant for dental impressions

Objetivo: Esse estudo piloto avaliou a atividade desinfetante do ácido peracético a 0,2% em corpos de prova de hidrocolóide irreversível. Materiais e métodos: Sua ação antimicrobiana foi investigada comparativamente à solução de glutaraldeído 2%, à solução de hipoclorito de sódio 2,5% e ao digluconato de clorexidina agregado à fórmula de um hidrocolóide irreversível. Foram selecionadas cepas de quatro microrganismos, Escherichia coli, Staphylococcus aureus, Bacilus proteus e Candida albicans para inoculação nos meios de cultura. As amostras de hidrocolóide irreversível foram divididas aleatoriamente em cinco grupos...

Evaluation of continuous 4-day exposure to peracetic acid as a treatment for Ichthyophthirius multifiliis.

The parasitic ciliate Ichthyophthirius multifiliis infests all species of freshwater fish and can cause severe economic losses in fish breeding. The most effective treatment, malachite green, has been banned in Europe and North America for use in food fish production. Peracetic acid (PAA) was found to be toxic to I. multifiliis theronts at low concentrations. I. multifiliis-infested carp were exposed to 1 mg/l PAA in a dynamic exposure by means of peristaltic pumps. Five days after infestation, gills, tail fins, and skin below the dorsal fin were observed microscopically for I. multifiliis abundance. After PAA exposure, PAA-treated fish showed lower infestation of I. multifiliis in all investigated tissues than the unexposed control fish. The infestation increased in the control group whereas the infestation in the PAA-exposed groups significantly decreased (p = 0.0083, Bonferroni correction). The fish in the two exposure groups showed a slight reinfestation with I. multifiliis. This might be caused by a peroxide degradation (hydrolysis) and/or reduction of the delivered PAA concentration. Thus, PAA concentrations were possibly too low to be effective on the released trophonts and/or the infective theronts. This hypothesis is corroborated by the fact that the I. multifiliis in the gills, skin, and fins of the PAA-exposed carp were in an early developmental stage.

[Antiparasitic effects of peracetic acid (PAA) against infective stages (theronts) of white spot disease, Ichthyophthirius multifiliis in vitro]. / Antiparasitäre Effekte von Peressigsäure (PES) gegen infektiöse Stadien (Theronten) der Weisspünktchenkrankheit, Ichthyophthirius multifiliis in vitro.

White spot disease, caused by the protozoan parasite Ichthyophthirius multifiliis (I. multifiliis), invades nearly all fresh water fish species and causes huge economic losses. In Germany no protocide substance is legal for the treatment of I. multifilis. As an alternative substance the peracetic acid (PAA) was tested to treat the free invasive stage (theront) of the parasite. PAA concentrations of 0.3 ppm were able to kill all theronts in 120 min in our investigations. As a result of these investigations we recommend an interval-application of 0.3 to 0.5 ppm PAA for 30 to 150 min. This application should be prolonged for two life cycles of the parasite. Biotic parameters as e. g. fish species, and age as well as abiotic parameters as e. g. temperature, pH and organic load of the water could possibly influence the efficiency of the PAA application and should therefore be taken into account while picking the dosage and length of the PAA exposure.

[Application of peracetic acid for the treatment of juvenile sander (Sander lucioperca) during Ichthyophthirius multifiliis infestation]. / Einsatz von Peressigsäure zur Behandlung juveniler Zander (Sander lucioperca) bei Ichthyophthirius-multifiliis-Befall.

White spot disease caused by the ciliate protozoan parasite Ichthyophthirius multifiliis (I. m.), is one of the most dangerous diseases in aquaculture and ornamental fish breeding worldwide. The parasite is characterized by three developmental stages: a reproductive tomont, an infective theront and a parasitic trophont. In sander (Sander lucioperca) breeding I. m. causes serious economic losses. After banning of the traditional therapeutic agent malachite green we have to face a state of emergency for the treatment of the ichthyophthiriasis in Germany. The peracetic acid (PAA), characterized by positive therapeutical properties, might close this gap. The purpose of our investigations was the determination of the toxicity of PES to juvenile sander as well as the evaluation of the therapeutic effectiveness of the substance to combat I. m. For juvenile sander (length 3 cm) we determined a 24-h-LC50 of 1.14 (0.97; 1.3) ppm PES. In two investigations PAA was applied in daily intervals of 0.5; 1, 3, 5 and 24 h and concentrations of 0.5; 1; 1.5 and 2 ppm to treat I.-m.-infection in sander. In test I all sander (length 9 cm) died as a result of the I.-m.-infection. However, the PAA exposed fish survived longer than the PES-free controls! This might be due to a disinfection of other pathogens by PAA. In test II, the fish (length 12 cm) were less infected than fish in test I. Four of six fish died in the group exposed with 2 ppm PAA for 24 hours. The abundance of I.-m.-trophonts was determined in mucus, fin and gill tissues of all fish. Significant differences could not be observed between test I and test II because of dissimilar: 1. exposure in time and concentration, 2. age and condition of the fish and 3. homogenity of the variances. Therefore, no therapy strategy was successful while fighting the parasitic trophonts protected by the overlaying fish tissues. We speculate that a successful therapy of I. m. with PAA is, as known e.g. for malachite green, only possible while fighting the free living stages theronts and tomonts. This will be part of our subsequent investigations.

Practical considerations in converting to Renalin 100 for dialyzer reprocessing.

It is clear from our findings (shown in Figs. 2, 3) that the cost of Renalin 100 is equal to or less than the cost of Renalin on a liter-to-liter basis. The decreased cost may be due to the elimination of the need to discard expired, diluted Renalin and the ability to use the small amount of Renalin 100 remaining in the container for making disinfectant solutions for disinfecting caps. The use of Renalin 100 leads to a 65% reduction in case count and storage space, as well as a 21% decrease in product weight. This means decreased costs in shipping and worker exertion to move this product. It is interesting that the 65% determination is virtually identical to the theoretical value advertised. The decreased waste generated was substantial. Cardboard waste was reduced by 78% and plastic waste was decreased by 72%. Even in this moderately sized facility this meant a decrease in waste generation of 780 lbs. annually. Extrapolation of this number across reprocessing centers in the United States would suggest that the widespread use of Renalin 100 would produce great domestic environmental gains. Because there is no diluting and mixing of Renalin 100, there is a substantial savings of time for personnel. The 95% time saving in this facility accounts for over two full weeks of technician time. In addition, the elimination of mixing and diluting decreases technician exposure to the sterilant. Finally, automated mixing and diluting eliminates the possibility of human error in preparing the sterilant and adds to the consistency of the reprocessing procedure.

Evaluation of copper sulphate, formalin and peracetic acid in footbaths for the treatment of digital dermatitis in cattle.

The efficacy of three non-antibiotic products (copper sulphate, formalin and peracetic acid) was compared with the efficacy of erythromycin, when the four substances were applied in footbaths for the treatment of cows with digital dermatitis. The cows were divided into four groups on the basis of their current housing and randomly allocated to one of the four treatments. Cattle allocated to the non-antibiotic treatments were footbathed daily for seven days, but the cattle treated with erythromycin were footbathed for two days only. Complete records were obtained for 252 lesions from 169 cows. There were significant reductions in the lesion scores of all four groups, but there was no significant effect of treatment and no significant interaction between treatment and time.

Comparison of topical application of oxytetracycline and four nonantibiotic solutions for treatment of papillomatous digital dermatitis in dairy cows.

OBJECTIVE: To compare efficacy of topical treatment with oxytetracycline solution or 1 of 4 nonantibiotic solutions among dairy cows with papillomatous digital dermatitis (PDD). DESIGN: Randomized field trial. ANIMALS: 66 cows in a single herd. PROCEDURE: Cows were randomly assigned to be treated with oxytetracycline solution; a commercial formulation of soluble copper, peroxide compound, and a cationic agent; 5% copper sulfate solution; acidified ionized copper solution; hydrogen peroxide-peroxyacetic acid solution; or tap water. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion scores were recorded. RESULTS: On the basis of pain and lesion scores, oxytetracycline and the commercial formulation appeared equally effective for treatment of PDD and significantly more effective than 5% copper sulfate solution, acidified ionized copper solution, hydrogen peroxide-peroxyacetic acid solution, and tap water. Proportions of cows with signs of pain or visible lesions after treatment were significantly lower for cows treated with oxytetracycline or the commercial formulation than for cows in the other groups. CLINICAL IMPLICATIONS: Oxytetracycline and a commercial formulation of soluble copper, peroxide compound, and a cationic agent appeared to be effective for treatment of PDD in dairy cows.

[Behavioral response of cows after intrauterine application of disinfectants for treatment of endometritis]. / Das Verhalten von Kühen nach intrauteriner Applikation von Desinfizienzien zur Behandlung der Endometritis.

Seventy-five animals were investigated in an attempt to study the chronological process of response to vaginal irritation by application of disinfectants for endometritis therapy. Aqueous peracetic acid solutions and Lugol solution were used. Cows reacted to intrauterine application of disinfectant drugs with tail lifting, pressing and sometimes groaning as expression of pain. We tried to quantify this response by registration of these different signs longer than two hours after treatment. The responses are caused by reflux of solution from the uterus into the vagina. They were different and depending on reflux volume, used drugs and their concentration. In comparison to peracetic acid solutions, the application of Lugol with 0.5% iodine seemed to induce a more intensive response to application.

Technical and economic feasibility of reusing disposable perfusion cannulae.

The reuse of disposable devices is a potential source of significant cost savings to hospitals. Venous and arterial perfusion cannulae under new and reused conditions were selected to identify the clinical, safety, technical, logistic, and economic issues that must be addressed to realize these savings. Single- and dual-stage venous and arterial cannulae from two manufacturers were tested when new, after initial clinical use, and after a single clinical use plus up to nine simulated reuses. Reuse was simulated by end-to-end bending, coupling and uncoupling the connectors, and by two 1-hour soaks in plasma at 4 degrees C and 40 degrees C, respectively. Cannulae were decontaminated and then sterilized by a peracetic acid based liquid chemical sterilization system following each use/reuse. Sterilization was validated by eliminating Bacillus subtilis spores from the cannulae on each of five consecutive cycles. Cannulae were tested for physical changes, functional integrity, biocompatibility, and in vivo performance in sheep. A cost minimization analysis was also performed. No clinically important differences were found between new and reused cannulae, even after nine simulated reuses. Mechanical changes were less than 20% on all variables studied and were undetectable by experienced cardiac surgeons in selective evaluation. Sterilization was successfully achieved. Reusing cannulae for times would reduce the cost per procedure from $53 to $19 (64%). Perfusion cannulae tested can be safely and efficaciously used five times. This study suggests that reuse would result in a small incremental savings; however, with more expensive devices and higher-volume sterilization procedures, the savings could be exponentially greater. Although this study demonstrates that it may be technically feasible and cost-effective to reuse disposable cannulae, the U.S. Food and Drug Administration does not sanction the reuse of disposable cannulae.

Peroxyacetic acid effect on the bacteriologic status of war wound.

In this study, the efficiency of peroxyacetic acid as a local antiseptic in war wound healing was investigated. Peroxyacetic acid was specially prepared for local application. The acidity was reduced from pH 2 to pH 5 using acetate buffer, the concentration was reduced to 0.2% and the use of sulfuric acid was avoided in the peroxyacetic acid preparation. Thirty-five patients with at least two similar wounds requiring daily dressing were included on a voluntary basis. Cranial wounds and wounds on the right side of the body were treated by peroxyacetic acid compresses, while other wounds were treated by the application of hypertonic NaCl solution. On day 12, the wounds treated by peroxyacetic acid (chi 2 = 52; df = 4, P < 0.001) were observed to be statistically significantly cleansed than the wounds treated conventionally. The use of peroxyacetic acid as a local antiseptic has not yet been described in the available literature. The possibilities and efficiency of peroxyacetic acid for this purpose, previously prepared for use in living tissue, are emphasized.