Low-temperature Hydrogen Peroxide Gas Research Articles

Monitoring the Effective Sterilization of Low-Temperature Hydrogen Peroxide Gas Plasma Sterilizers in 58 Hospitals - 22 PLADs, China, June 2015-December 2019.

What is already known on this topic?Hydrogen peroxide sterilizeation is widely used for luminal devices. However, the low penetrability of the sterilant is of major concern.What is added by this report?This report investigated the effective sterilization of low-temperature hydrogen peroxide gas plasma sterilizers and compared the applicability of different biological monitoring methods based on medical luminal devices.What are the implications for public health practice?It is recommended to use a biological process challenge device for monitoring the sterilization of luminal devices with low-temperature hydrogen peroxide gas plasma sterilizers.

Decontamination of N95 masks for re-use employing 7 widely available sterilization methods.

The response to the COVID-19 epidemic is generating severe shortages of personal protective equipment around the world. In particular, the supply of N95 respirator masks has become severely depleted, with supplies having to be rationed and health care workers having to use masks for prolonged periods in many countries. We sought to test the ability of 7 different decontamination methods: autoclave treatment, ethylene oxide gassing (ETO), low temperature hydrogen peroxide gas plasma (LT-HPGP) treatment, vaporous hydrogen peroxide (VHP) exposure, peracetic acid dry fogging (PAF), ultraviolet C irradiation (UVCI) and moist heat (MH) treatment to decontaminate a variety of different N95 masks following experimental contamination with SARS-CoV-2 or vesicular stomatitis virus as a surrogate. In addition, we sought to determine whether masks would tolerate repeated cycles of decontamination while maintaining structural and functional integrity. All methods except for UVCI were effective in total elimination of viable virus from treated masks. We found that all respirator masks tolerated at least one cycle of all treatment modalities without structural or functional deterioration as assessed by fit testing; filtration efficiency testing results were mostly similar except that a single cycle of LT-HPGP was associated with failures in 3 of 6 masks assessed. VHP, PAF, UVCI, and MH were associated with preserved mask integrity to a minimum of 10 cycles by both fit and filtration testing. A similar result was shown with ethylene oxide gassing to the maximum 3 cycles tested. Pleated, layered non-woven fabric N95 masks retained integrity in fit testing for at least 10 cycles of autoclaving but the molded N95 masks failed after 1 cycle; filtration testing however was intact to 5 cycles for all masks. The successful application of autoclaving for layered, pleated masks may be of particular use to institutions globally due to the virtually universal accessibility of autoclaves in health care settings. Given the ability to modify widely available heating cabinets on hospital wards in well-resourced settings, the application of moist heat may allow local processing of N95 masks.

Is plasma sterilization the modality of choice of sterilization today for endourological procedures such as ureterorenoscopy and retrograde intrarenal surgery? A single-center retrospective evaluation of 198 patients.

Introduction:The prevalence of infective complications among patients undergoing Retrograde Intrarenal Surgery (RIRS) for renal stone is 1.7%-18%, including fever, Systemic Inflammatory Response Syndrome (SIRS) and sepsis. The infectious complications of RIRS can be minimised by strict aseptic precautions and plasma sterilization. The Sterrad Next Generation (Sterrad NX) System, a low-temperature sterilizer represents the next generation of low-temperature hydrogen peroxide gas plasma sterilizers. This study was conducted to evaluate the efficacy of plasma sterilization among patients undergoing ureterorenoscopy (URS) and RIRS. The primary endpoint of this study was incidence of septicemia or related complications. Till date, there is no study on the incidence of infection rate in RIRS in relation to a specific mode of sterilization.Material and Methods:This is a retrospective study comprising of 198 patients undergoing URS and/or RIRS. The parameters studied were incidence of post-operative fever, Systemic Inflammatory Response Syndrome (SIRS), pyelonephritis or septicemic shock.Results:Out of 198 patients, incidence of post-operative fever was 3.5%, SIRS was 1.7%, pyelonephritis was 0.7% and septicemic shock was 0%. This is statistically significantly low septicemia rate among patients undergoing URS and /or RIRS as compared to the available literature. No health hazards of plasma sterilization were noted. No damage to the endoscopes or instruments was noted.Conclusion:Sterrad NX based on hydrogen peroxide gas plasma (HPGP) technology is highly efficacious, safe and the modality for sterilization of instruments, including heat labile instruments such as semi rigid, flexible and chip on the tip endoscopes and other EndoUrology armamentarium.

How to Sterilize 3D Printed Objects for Surgical Use? An Evaluation of the Volumetric Deformation of 3D-Printed Genioplasty Guide in PLA and PETG after Sterilization by Low-Temperature Hydrogen Peroxide Gas Plasma

Introduction: In the present time, there is rapid development in the application of 3D printing technology in surgery. One of the challenges encountered by the surgeon is the sterilization of these 3D-printed objects for use in the operating room. Materials and Methods: Forty-two identical cutting guides used for genioplasty were 3D-printed: twenty-one in Polylactic acid (PLA) and twenty-one in Polyethylene terephthalate glycol (PETG). The guides were CT scanned after printing. They were then sterilized with the low-temperature hydrogen peroxide gas plasma technique (Sterrad®). A CT scan of the guides was also performed at T1 (after printing) and T2 (after sterilization). A software (Cloudcompare ®) was then used to accurately compare the volume of each guide at T0 (the initial computer-aided designed guide) vs T1 and T1 vs T2. Statistical analysis was then performed. Results: Although there are differences that are statistically significant for each series between T0 and T2 and T1 and T2 for both PLA and PETG, this had no impact on the clinical use of sterilized objects using hydrogen peroxide sterilization technique because these morphological differences were minimal at less than 0.2mm. Conclusion: Morphological deformations induced by the hydrogen peroxide sterilization are sub-millimeter and acceptable for surgical use. The hydrogen peroxide sterilization is, therefore, an alternative to avoid the deformation of 3D-printed objects made from PLA and PETG during conventional steam sterilization (autoclave). To the best of our knowledge, this is the first study regarding the morphologic deformation of 3D-printed objects in PLA and PETG after sterilization for medical use.

Sterilization Efficacy of a Below 40°C Plasma Processes Assessed by a Biological Indicator

Biodegradable biopolymers have been widely used in biomaterials for tissue engineering. Sterilization is a process by which a product can be made free of contamination from microorganisms such as bacteria, yeasts, and viruses. When sterilizing biodegradable scaffolds, the sterilization technique chosen must maintain the structural and biochemical properties of the scaffolds to ensure that the scaffolds can fulfill their intended purposes post-sterilization. In addition, in response to the development of customized, rapid and accurate medical devices via 3D printed biomaterials, sterilization of such devices by low-temperature hydrogen peroxide (H2O2) gas plasma (HPGP) will provide new capabilities not only for rapidly manufacturing customized medical devices but also for producing sterile end-use parts. This device uses a below 40°C temperature plasma with H2O2 activated by ultraviolet light irradiation processes to evaluate the sterilization efficacy with a biological indicator. The results demonstrated several parameter combinations for HPGP that can achieve sterilization at temperatures below 40°C. Therefore, the parameters associated with this HPGP device have the potential to provide a sterilization process applicable for future development of biopolymer devices manufactured by 3D printing. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License .

Optimization of sterilization methods for electrospun poly(ε-caprolactone) to enhance pre-osteoblast cell behaviors for guided bone regeneration

The aim of this study was to determine the optimal sterilization procedure for biodegradable polyester-based guided bone regeneration membranes. The effects of sterilization using low-temperature hydrogen peroxide gas plasma, 75% ethanol (EtOH; two soaking times), and ultraviolet radiation on the structure and biological properties of electrospun poly(ε-caprolactone) membranes were investigated. The results demonstrated that all were effective sterilization methods. The membranes were then assessed for surface structure, wettability, and in vitro cellular responses including osteogenic differentiation by seeding with pre-osteoblasts (MC3T3-E1 cells). The cells grew well on all the sterilized membranes. The low-temperature hydrogen peroxide gas plasma–sterilized membranes, which exhibited significantly improved hydrophilicity ( p < 0.05), were better for cell osteogenic differentiation compared to the membranes sterilized by other methods. In addition, the cell behavior on the membranes sterilized by EtOH was superior to those sterilized by ultraviolet radiation. Finally, EtOH soaking time appeared to influence cell behavior. The results suggested that low-temperature hydrogen peroxide gas plasma treatment is the most promising method to sterilize electrospun poly(ε-caprolactone) membranes for guided bone regeneration.

20 Diopter Condensing Lens with Disintegrating Paint; A Potential Problem?

Purpose: To report a potential complication resulting from an inappropriate sterilization method of a 20 Diopter condensing lens intended for use during scleral buckling surgery. Results: Repeated or prolonged sterilization with STERRAD, low temperature hydrogen peroxide gas plasma, can result in chipping of paint on medical equipment. The retention of particulate material in the eye exposes the patient to increased risk of sub-conjunctival granuloma or a misdiagnosis and may result in further surgery. The institutional policy has been revised to prevent recurrence of such event. Conclusion: Disinfection or sterilization of surgical equipment should be performed according to the manufacturer’s recommendations and surgical equipment should be inspected pre-operatively.

Adverse Events with Low Temperature Hydrogen Peroxide Gas Plasma Sterilisation Reported by Certified Sterilisation Service Technicians and Certified Sterilisation Specialists in Japan

Adverse Events with Low Temperature Hydrogen Peroxide Gas Plasma Sterilisation Reported by Certified Sterilisation Service Technicians and Certified Sterilisation Specialists in Japan

Effects of Low-Temperature Hydrogen Peroxide Gas Plasma Sterilization on In Vitro Cytotoxicity of Poly(ϵ-Caprolactone) (PCL)

Our objective was to determine whether low-temperature hydrogen peroxide (H2O2) gas plasma sterilization of porous three-dimensional poly(ϵ-caprolactone) (PCL) constructs significantly inhibits cellular metabolism of canine chondrocytes. Porous cylindrical constructs were fabricated using fused deposition modeling and divided into four sterilization groups. Two groups were sterilized with low-temperature H2O2 gas plasma (LTGP) and constructs from one of those groups were subsequently rinsed with Dulbecco’s Modified Essential Media (LTGPDM). Constructs in the other two groups were disinfected with either 70% isopropyl alcohol or exposure to UV light. Canine chondrocytes were seeded in 6-well tissue-culture plates and allowed to adhere prior to addition of PCL. Cellular metabolism was assessed by adding resazurin to the tissue-culture wells and assessing conversion of this substrate by viable cells to the fluorescent die resorufin. This process was performed at three times prior to addition of PCL and at four times after addition of PCL to the tissue-culture wells. Metabolism was not significantly different among the different tissue-culture wells at any of the 3 times prior to addition of PCL. Metabolism was significantly different among the treatment groups at 3 of 4 times after addition of PCL to the tissue culture wells. Metabolism was significantly lower with constructs sterilized by LTGP than all other treatment groups at all 3 of these times. We conclude that LTGP sterilization of PCL constructs resulted in significant cytotoxicity to canine chondrocytes when compared to PCL constructs disinfected with either UV light exposure or 70% isopropyl alcohol.

Two-stage Reimplantation in Infected Total Knee Arthroplasty Using a Re-sterilized Tibial Polyethylene Insert and Femoral Component

Infection in total knee arthroplasty (TKA) is a challenging complication. We reviewed 20 cases of infected TKAs treated by two-stage reimplantation procedure involving the use of a temporary articulating system composed of autoclaved femoral component, low temperature hydrogen peroxide gas plasma sterilized polyethylene insert, and antibiotic-impregnated bone cement. The knee and functional score of the Knee Society scoring system at the last follow (average, 64.8 months) up was 86.2 points and 78.8 points. The success rate in terms of eradication of infection was 95% (19/20 knees). Use of a temporary articulating system composed of the re-sterilized components with antibiotic-impregnated bone cement was an effective therapy not only for the eradication of the infection but also for the recovery of soft tissue health and knee function.

Hydrogen Peroxide Vapour in the Proximity of Hydrogen Peroxide Sterilisers

Background: Some employees engaged in central services in a hospital have experienced irritation to the eyes and throat near the hydrogen peroxide (HP) steriliser. Method: The concentrations of hydrogen peroxide vapour (HPV) in the proximity of HP sterilisers (low-temperature hydrogen peroxide gas plasma steriliser: Sterrad NX®, Sterrad 100S®, and Sterrad 200®, Johnson & Johnson, and Low-temperature vaporized hydrogen peroxide steriliser: Amsco V-PRO1®, Sakura Seiki) were measured with an electrochemical detector. Results: HPV was present at higher concentrations than anticipated. Conclusion: Adequate air conditioning, donning gloves for bag handling, supplied-air respirator use for door opening, and other measures for the security of healthcare personnel should be seriously reevaluated.

Inactivation of Animal and Human Prions by Hydrogen Peroxide Gas Plasma Sterilization

Prions cause various transmissible spongiform encephalopathies. They are highly resistant to the chemical and physical decontamination and sterilization procedures routinely used in healthcare facilities. The decontamination procedures recommended for the inactivation of prions are often incompatible with the materials used in medical devices. In this study, we evaluated the use of low-temperature hydrogen peroxide gas plasma sterilization systems and other instrument-processing procedures for inactivating human and animal prions. We provide new data concerning the efficacy of hydrogen peroxide against prions from in vitro or in vivo tests, focusing on the following: the efficiency of hydrogen peroxide sterilization and possible interactions with enzymatic or alkaline detergents, differences in the efficiency of this treatment against different prion strains, and the influence of contaminating lipids. We found that gaseous hydrogen peroxide decreased the infectivity of prions and/or the level of the protease-resistant form of the prion protein on different surface materials. However, the efficiency of this treatment depended strongly on the concentration of hydrogen peroxide and the delivery system used in medical devices, because these effects were more pronounced for the new generation of Sterrad technology. The Sterrad NX sterilizer is 100% efficient (0% transmission and no protease-resistant form of the prion protein signal detected on the surface of the material for the mouse-adapted bovine spongiform encephalopathy 6PB1 strain and a variant Creutzfeldt-Jakob disease strain). Thus, gaseous or vaporized hydrogen peroxide efficiently inactivates prions on the surfaces of medical devices.

Effects of low temperature hydrogen peroxide gas on sterilization and cytocompatibility of porous poly(d,l-lactic-co-glycolic acid) scaffolds

Biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) has been widely used as a scaffold in tissue engineering due to its excellent biocompatibility. However, PLGA scaffolds become structurally deformed during the sterilization process since they were hydrolytically unstable. In this study, the effects of hydrogen peroxide gas (HPG) were investigated on the deformation, sterilization and cytocompatibility of porous PLGA scaffolds and compared with those of ethylene oxide (EO) gas. Also, the effects of HPG treatment on the cellular responses of human articular chondrocytes were examined. HPG treatment resulted in neither deformation of PLGA nor its chemical modification, different from EO gas treatment. PLGA scaffolds inoculated with diverse strains of microorganisms were completely sterilized by HPG treatment. Moreover, the cytotoxicity of residual HPG occurring upon HPG treatment completely decreased as ventilation time increased. On the other hand, there was no significant difference in the proliferation and glycosaminoglycan synthesis of chondrocytes between EO gas-treated and HPG-treated PLGA scaffolds. These results suggest that HPG can be used as an alternative method for sterilizing various polymeric scaffolds and medical devices without structural deformation.

Sterilization effects on starPEG coated polymer surfaces: characterization and cell viability

Sterilization is frequently an issue for polymeric biomaterials including hydrogels, where autoclaving needs to be discarded, and gamma-irradiation and low temperature hydrogen peroxide gas plasma sterilization are already important alternatives. Coatings based on poly(ethylene glycol) are a well-known strategy to reduce unspecific protein interactions on biomaterial surfaces. Dense, ultrathin coatings of isocyanate terminated star-shaped poly(ethylene glycol) (starPEG) molecules have proven to be resistant to unspecific adsorption of proteins and enable direct biofunctionalization. The effectivity and stability of the starPEG coatings on poly(vinylidene fluoride) (PVDF) were studied after gamma-irradiation (normed dosis 25 kGy) and plasma sterilization (Sterrad 100S). The selected surface properties determined were: surface composition (X-ray photoelectron spectroscopy, XPS), wettability (sessile drop contact angle) and protein adsorption by fluorescence microscopy (Avidin-TexasRed, Bovine Serum Albumin-Rhodamin). Preliminary cell experiments with the cell line L929 were performed prior and after sterilization to investigate the cell repellence of the starPEG coatings as well as cell viability and specific cell adhesion on GRGDS-modified coatings. The starPEG coating undergoes a slight oxidation due to plasma and gamma-sterilization; this represents a minor variation confirmed by XPS and contact angle results. The non-sterilized starPEG and the plasma-sterilized coatings are protein repellent, however the protein adsorption on starPEG coated substrates is much stronger after gamma-sterilization for both avidin and bovine serum albumin. The cell experiments indicate that the starPEG coatings are appliable homogeneously by incubation and are non-cell adherent. Moreover, after both sterilization processes the starPEG coatings remain cell repellent and the GRGDS-modified coatings presented vital cells. Thus we conclude that the plasma sterilization is more convenient for the starPEG coatings and GRGDS-modified starPEG coatings.

欧州における滅菌の最新事情と新型過酸化水素低温プラズマ滅菌装置の位置付け(第82回日本医科器械学会大会ランチョンセミナー5記録)

欧州における滅菌の最新事情と新型過酸化水素低温プラズマ滅菌装置の位置付け(第82回日本医科器械学会大会ランチョンセミナー5記録)

Evaluation of the efficacy and usefulness of low temperature hydrogen peroxide gas plasma sterilization system for endoscopies

目的 探讨STERRAD(r)100S过氧化氢等离子低温灭菌系统在内窥镜消毒中的临床应用效果,并与福尔马林熏蒸灭菌法进行比较.方法 2005年1-3月,采用福尔马林熏蒸器械灭菌法完成92台手术104次熏蒸共2 706件内窥镜手术器械灭菌.2005年1-3月采用STER-RAD(r)100S过氧化氢等离子低温灭菌系统完成165台手术180个循环共4 950件内窥镜手术器械灭菌.对比两种方法的器械损耗率、手术感染率,并发放问卷调查医护人员对两种灭菌方法的满意度.结果 STERRAD(r)100S过氧化氢等离子低温灭菌系统在器械损耗率、手术感染率和医护人员满意度指标上均明显优于福尔马林熏蒸灭菌法(P＜0.05).结论 STERRAD(r)100S过氧化氢等离子低温灭菌系统具有环保、安全、低温、快速、节省费用和适用范围广的优点,具有极高的经济价值和社会价值。

Comparison of low-temperature hydrogen peroxide gas plasma sterilization for endoscopes using various Sterrad™ models

This study compared the effectiveness of sterilizing four types of endoscope using different models of the Sterrad system (Sterrad 50, 100, 100S and 200). Sterilization levels meeting international requirements were attained in all cases with carriers inoculated with Geobacillus stearothermophilus spores. The endoscopes were tested in half cycles ('overkill'). This is the first study to compare the Sterrad models marketed to date in terms of effective sterilization of endoscopes with narrow lumens.

Measures taken to reduce damage and repair costs of rigid endoscopes during their handling and processing in surgical practice

An increased number of surgical procedures using endoscopic techniques has resulted in a more frequent use of rigid endoscopes. A side effect of this is that more instrument damage has been noticed. Measures must be taken in instrument handling procedures to reduce the incidence of instrument damage and the cost of instrument repairs. Impacts of such changes have been studied. The incidence and types of damage to rigid endoscopes was followed during a six-year period. During the time period of the study certain changes in instrument handling and processing were introduced. Improved education and training of personnel was instituted as well as a change in sterilization practice. Measures taken in instrument processing have resulted in a total reduction of instrument damage of 35%. High temperature damage to lenses was reduced in the order of 80% when low-temperature hydrogen peroxide gas plasma was applied for sterilization instead of steam autoclaving. The introduction of educational and training programs to raise the awareness of the staff in instrument handling and the use of low-temperature gas plasma for sterilization can considerably reduce the incidence of instrument damage and reduce the cost for instrument repair. It can be assumed that the reduction of damage to instruments also has a beneficial influence on the quality of the endoscopic surgical procedures because less time is lost, and possibly the image quality can be improved.

Contamination of bronchoscopes with Mycobacterium tuberculosis and successful sterilization by low-temperature hydrogen peroxide plasma sterilization

Background: The transmission of mycobacteria by bronchoscopes has been reported several times in the last years. To explore methods to prevent transmission of tuberculosis in this way, we sterilized contaminated bronchoscopes with low-temperature hydrogen peroxide gas plasma sterilization. Methods: Bronchoscopes were contaminated with Mycobacterium tuberculosis and decontaminated with a washer/disinfecter (“normal washing”). Some were additionally disinfected with glutaraldehyde (“intensive washing”). Afterward the bronchoscopes were sterilized by low-temperature hydrogen peroxide plasma sterilization. Results: After normal washing, 8/17 samples had positive results by culture, and 7/17 had positive results by nucleic acid amplification technique. After intensive washing, all samples had negative results by culture, and 10/25 had positive results by nucleic acid amplification technique; after sterilization with low-temperature hydrogen peroxide plasma sterilization, all samples had negative results by culture and nucleic acid amplification technique. Conclusion: Washing of bronchoscopes, as performed normally, is not sufficient for decontamination of bronchoscopes. Additional disinfection is recommended. If the nucleic acid amplification technique is used for diagnostic procedures, sterilization by low-temperature hydrogen peroxide plasma sterilization is recommended to avoid false-positive results.

Effect of gas-plasma sterilization on the osteoinductive capacity of demineralized bone matrix.

The current study evaluated the effect of low-temperature hydrogen peroxide gas plasma sterilization on the osteoinductive capability of human demineralized bone matrix using a rat model. Twelve athymic rats received three separate implants consisting of steam-sterilized demineralized bone matrix (negative control), sterile-harvest demineralized bone matrix (positive control), and gas-plasma-sterilized demineralized bone matrix. A demineralized bone matrix pellet from each sterilization group was placed individually into one of three separate soft tissue pockets created in the epaxial musculature of each rat. All 12 rats were euthanized 9 weeks after implantation. Each implantation site was removed along with 0.5-cm normal tissue around the implant. Histologic examination was done on each implant site to determine the presence or absence of new bone, cartilage, or bone marrow elements. All 12 sterile harvest demineralized bone matrix sites histologically contained new bone elements, whereas none of the negative control or gas plasma sterilized demineralized bone matrix sites contained any of these same elements. The results of this study indicate that demineralized bone matrix sterilized with low-temperature, gas-plasma sterilization loses its osteoinductive capacity in a manner similar to that of steam-sterilized demineralized bone matrix, making low-temperature, gas- plasma sterilization unsuitable as a method of secondary sterilization of demineralized bone matrix.