Rapid Readout Biological Indicator Research Articles

Use of a Pressure Cooker to Achieve Sterilization for an Expeditionary Environment.

Sterilization of healthcare instruments in an expeditionary environment presents a myriad of challenges including portability, cost, and sufficient electrical power. Using pressure cookers to sterilize instruments presents a low-cost option for sterilization in prehospital settings. This project's objective was to determine if sterility can be achieved using a commercially available pressure cooker. Presto® 4-quart stainless steel pressure cookers were heated using Cuisinart® CB-30 cast-iron single burners. One 3M™ Attest™ 1292 Rapid Readout Biological Indicator and one 3M™ Comply™ SteriGage™ integrator strip were sealed in a Henry Schein® Sterilization Pouch and placed in a pressure cooker and brought to a pressure of 103.4kPa. Sterility was verified after 20 minutes at pressure. The Attest vials were incubated in a 3M Attest 290 Auto-Reader for 3 hours with a control vial. Sterility using the pressure cooker was achieved in all tested bags, integrator strips, and Attest vials (n = 128). The mean time to achieve the necessary 103.4kPa was 379 seconds (standard deviation (SD) = 77). Neither the ambient temperature nor humidity were found to affect the pressure cooker's time to achieve adequate pressure, nor the achieved depth on the integrator strip (all p > .05). This study provides evidence that sterilization is possible with offthe- shelf pressure cookers. Though lacking US Food and Drug Administration (FDA) approval, the use of this commercially available pressure cooker may provide a method of sterilization requiring minimal resources from providers working in expeditionary environments.

The effectiveness of biological indicator and e-tracking system in sterilization failure event

Purpose: Steam sterilization is the most popular method used in hospital, but the failure rate varies from 1% to 65 %. Use biological and chemical indicators are the gold standard for sterilization monitoring in the healthcare facilities. We wish to have a chance to verify the accuracy of these indicators. Methods: At 10:10am Sep 5 by 2014, the hospital CSR (Central Service Room) encountered a florescent positive biological indicator after incubated 160 minutes. Then the head nurse prompt click the button in the e-tracking system to alarm the recall process hospital-wide at 10:13am. Although the sterilizer record and Bowie-Dick test, class 4 chemical indicator were passed, the class 5 chemistry indicator is fail. CSR also contacted infection control department, service engineer, supervisor of CSR and operating room (OR) for this emergency event. Results: The e-tracking system show immediately 47 instrument sets processed in that questionable load, 5 of 47 already sent to operative room and children hospital operative room. With this system, CSR successfully recall 4 packs, only 1 pack was used at 10:18am of the day due to pediatric OR nurse misunderstood the risk of sterilization failure. The questionable sterilizer was removed from service, and all the relative loads were reprocessed and also started to investigate the root causes. Finally, we found this rare event was due to CSR operator error finally. Conclusions: We also found we need to educate the OR nurses, correct the CSR operation procedures, well trained the new employee, and audit the sterilizer record and monitoring products. The valued rapid readout biological indicator alarm in a short period and did do a great job to alarm the sterilization failure and prevent from pose the patient in infection risk.

Evaluation of a new rapid readout biological indicator for use in 132°C and 135°C vacuum-assisted steam sterilization cycles

Sterilization is a process that cannot be inspected or tested in a practical manner to assure that all microorganisms have been inactivated. The process must therefore be validated for all of the specific items processed or monitored on a per cycle basis. A new, faster rapid readout biological indicator (RRBI) has been developed for use in 132°C and 135°C vacuum-assisted steam sterilization cycles. The aim of this study was to evaluate the performance of this new 1-hour readout RRBI at 132°C in side-by-side testing with an existing 3-hour readout RRBI and also evaluate the performance of the new RRBI in 135°C cycles. Readout responses of 1 hour (fluorescent) and 48 hours and 7 days (growth) of the new RRBI were compared with 3-hour, 48-hour, and 7-day readouts of the 3-hour RRBI following exposures in 132°C cycles using a highly controlled test vessel, ie, a steam resistometer. Additional testing of the 1-hour RRBIs was also performed in 135°C cycles. The number and percentage of fluorescent-positive 1-hour RRBIs were virtually identical to those of the 3-hour RRBIs after 1 and 3 hours of incubation, respectively. Testing of the 1-hour RRBI in 135°C cycles paralleled the results of the testing at 132°C but with the expected shorter exposure times. The results of this study suggest that the 1-hour RRBI is equivalent to the 3-hour RRBI and would be suitable for use in monitoring dynamic air removal steam sterilization cycles at both 132°C and 135°C per recommended practice guidelines.

Mechanism of the hydrolysis of 4-methylumbelliferyl-beta-D-glucoside by germinating and outgrowing spores of Bacillus species.

To determine the mechanism of the hydrolysis of 4-methylumbelliferyl-beta-D-glucopyranoside (beta-MUG) by germinating and outgrowing spores of Bacillus species. Spores of B. atrophaeus (formerly B. subtilis var. niger, Fritze and Pukall 2001) are used as biological indicators of the efficacy of ethylene oxide sterilization by measurement of beta-MUG hydrolysis during spore germination and outgrowth. It was previously shown that beta-MUG is hydrolysed to 4-methylumbelliferone (MU) during the germination and outgrowth of B. atrophaeus spores (Chandrapati and Woodson 2003), and this was also the case with spores of B. subtilis 168. Germination of spores of either B. atrophaeus or B. subtilis with chloramphenicol reduced beta-MUG hydrolysis by almost 99%, indicating that proteins needed for rapid beta-MUG hydrolysis are synthesized during spore outgrowth. However, the residual beta-MUG hydrolysis during spore germination with chloramphenicol indicated that dormant spores contain low levels of proteins needed for beta-MUG uptake and hydrolysis. With B. subtilis 168 spores that lacked several general proteins of the phosphotransferase system (PTS) for sugar uptake, beta-MUG hydrolysis during spore germination and outgrowth was decreased >99.9%. This indicated that beta-MUG is taken up by the PTS, resulting in the intracellular accumulation of the phosphorylated form of beta-MUG, beta-MUG-6-phosphate (beta-MUG-P). This was further demonstrated by the lack of detectable glucosidase activity on beta-MUG in dormant, germinated and outgrowing spore extracts, while phosphoglucosidase active on beta-MUG-P was readily detected. Dormant B. subtilis 168 spores had low levels of at least four phosphoglucosidases active on beta-MUG-P: BglA, BglH, BglC (originally called YckE) and BglD (originally called YdhP). These enzymes were also detected in spores germinating and outgrowing with beta-MUG, but levels of BglH were the highest, as this enzyme's synthesis was induced ca 100-fold during spore outgrowth in the presence of beta-MUG. Deletion of the genes coding for BglA, BglH, BglC and BglD reduced beta-MUG hydrolysis by germinating and outgrowing spores of B. subtilis 168 at least 99.7%. Assay of glucosidases active on beta-MUG or beta-MUG-P in extracts of dormant and outgrowing spores of B. atrophaeus revealed no enzyme active on beta-MUG and one enzyme that comprised > or =90% of the phosphoglucosidase active on beta-MUG-P. Partial purification and amino-terminal sequence analysis of this phosphoglucosidase identified this enzyme as BglH. Generation of MU from beta-MUG by germinating and outgrowing spores of B. atrophaeus and B. subtilis is mediated by the PTS-driven uptake and phosphorylation of beta-MUG, followed by phosphoglucosidase action on the intracellular beta-MUG-P. The major phosphoglucosidase catalyzing MU generation from beta-MUG-P in spores of both species is probably BglH. This work provides new insight into the mechanism of uptake and hydrolysis of beta-MUG by germinating and outgrowing spores of Bacillus species, in particular B. atrophaeus. The research reported here provides a biological basis for a Rapid Readout Biological Indicator that is used to monitor the efficacy of ethylene oxide sterilization.

New disinfection and sterilization methods.

New disinfection methods include a persistent antimicrobial coating that can be applied to inanimate and animate objects (Surfacine), a high-level disinfectant with reduced exposure time (ortho-phthalaldehyde), and an antimicrobial agent that can be applied to animate and inanimate objects (superoxidized water). New sterilization methods include a chemical sterilization process for endoscopes that integrates cleaning (Endoclens), a rapid (4-hour) readout biological indicator for ethylene oxide sterilization (Attest), and a hydrogen peroxide plasma sterilizer that has a shorter cycle time and improved efficacy (Sterrad 50).

Comparison of a Rapid Readout Biological Indicator for Steam Sterilization with Four Conventional Biological Indicators and Five Chemical Indicators

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Comparison of a Rapid Readout Biological Indicator for Steam Sterilization With Four Conventional Biological Indicators and Five Chemical Indicators

AbstractObjective:In this study, we compare a new biological indicator that provides results within 3 hours with four conventional, 48-hour biological indicators and five chemical indicators.Design:Biological indicators tested included the conventional Attest 1262, Proof Plus, Assert, and Biosign, and the new Attest 1292 Rapid Readout biological indicator. Chemical indicators tested included Comply, Propper, Chemdi, Sterigage, and Thermalog S. Spore survival following 121°C in a gravity displacement sterilizer was measured by media color change after incubation for 24 and 48 hours at 56°C for the conventional biological indicators, fluorescence at 3 hours for the Attest 1292 Rapid Readout biological indicator, and color change for the chemical indicators. Each exposure time was replicated 12 times with five samples of each indicator per run (ie, 60 replicates per indicator).Results:At 48 hours, the conventional biological indicators Attest 1262, Proof Plus, Assert, and Biosign showed 100%, 95%, 88%, and 93% spore survival at 5 minutes' exposure; 0%, 0%, 0%, and 8% at 10 minutes; and all showed 0% survival at 15 minutes' exposure. Following a 3hour incubation, the Attest 1292 Rapid Readout biological indicator showed fluorescence at 100%, 72%, and 0% at 5, 10, and 15 minutes, respectively. The chemical indicators Comply, Propper, Chemdi, Sterigage, and Thermalog S revealed sterilization failure rates of 100%, 100%, 100%, 100%, and 100% at 5 minutes' exposure; 0%, 0%, 0%, 92%, and 100% at 10 minutes; and, 0%, 0%, 0%, 3%, and 27% at 15 minutes' exposure, respectively.Conclusions:The sensitivity of the Attest 1292 Rapid Readout biological indicator parallels that of conventional biological indicators. These data suggest that a 3hour rapid readout biological indicator is equivalent to a standard 48-hour biological indicator. Some chemical indicators (eg, Thermalog S) failed to indicate adequate sterilization at 15 minutes' exposure. These chemical indicators have the potential of causing unnecessary recall of adequately sterilized items.

Comparison of a Rapid Readout Biological Indicator for Steam Sterilization with Four Conventional Biological Indicators and Five Chemical Indicators

Comparison of a Rapid Readout Biological Indicator for Steam Sterilization with Four Conventional Biological Indicators and Five Chemical Indicators

Correction: Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

Correction: Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

Correction: Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

Correction: Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

A biological indicator (BI), based on fluorescent detection of a spore-associated enzyme, has been developed. We evaluated the new BI against five conventional self-contained BIs in a 121 degrees C gravity-displacement sterilizer and, packaged in towel packs and disposable steam test packs, in a 132 degrees C vacuum-assisted sterilizer. In the 121 degrees C gravity-displacement sterilizer, rapid readout BIs and conventional BIs were tested together in an otherwise empty chamber. Exposure times were 5, 10, and 15 minutes. In the 132 degrees C vacuum-assisted steam sterilizer, BIs were contained in towel packs or disposable steam test packs. Surgical packs were added to represent a full load. Exposure times were 0, 1, and 2 minutes. In gravity-displacement 5-minute cycles, the rapid readout BIs yielded 100% positive results within 30 minutes. The conventional BIs ranged from 72% to 100% positive in 48 hours. At 10 minutes, the rapid readout BIs were 83% positive after 3 hours, whereas the conventional BIs ranged from 0% to 37% positive after 48 hours. All indicators were negative after 15-minute exposures. In vacuum-assisted cycles, all indicators were negative after 3 minutes. After 1-minute exposures, the rapid readout BIs were 40% to 60% positive, whereas the conventional BIs were 15% to 20% positive. The rapid readout BIs are a more sensitive indicator of marginal steam sterilization cycles than conventional self-contained BIs. They yield results within 3 hours, as compared to 24 to 48 hours for the conventional BIs.

Evaluation of a Rapid Readout Biological Indicator for 121°C Gravity and 132°C Vacuum-Assisted Steam Sterilization Cycles

OBRECTIVE: A biological indicator (BI), based on fluorescent detection of a spore-associated enzyme, has been developed. We evaluated the new BI against five conventional self-contained BIs in a 121TC gravitydisplacement sterilizer and, packaged in towel packs and disposable steam test packs, in a 132'C vacuum-assisted sterilizer. DESIGN: In the 121TC gravity-displacement sterilizer, rapid readout BIs and conventional BIs were tested together in an otherwise empty chamber. Exposure times were 5, 10, and 15 minutes. In the 1320C vacuum-assisted steam sterilizer, BIs were contained in towel packs or disposable steam test packs. Surgical packs were added to represent a full load. Exposure times were 0, 1, and 2 minutes. RESUTIS: In gravity-displacement 5-minute cycles, the rapid readout BIs yielded 100% positive results within 30 minutes. The conventional BIs ranged from 72% to 100% positive in 48 hours. At 10 minutes, the rapid readout BIs were 83% positive after 3 hours, whereas the conventional BIs ranged from 0% to 37% positive after 48 hours. All indicators were negative after 15-minute exposures. In vacuum-assisted cycles, all indicators were negative after 3 minutes. After 1-minute exposures, the rapid readout BIs were 40% to 60% positive, whereas the conventional BIs were 15% to 20% positive. CONCLUSION: The rapid readout BIs are a more sensitive indicator of marginal steam sterilization cycles than conventional self-contained BIs. They yield results within 3 hours, as compared to 24 to 48 hours for the conventional BIs (Infect Control Hosp Epidemiol 1995;16:281286).

Evaluation of a Rapid Readout Biological Indicator for Flash Sterilization with Three Biological Indicators and Three Chemical Indicators

Evaluation of a Rapid Readout Biological Indicator for Flash Sterilization with Three Biological Indicators and Three Chemical Indicators

Evaluation of three conventional biological indicators and a rapid readout biological indicator for flash sterilization

Evaluation of three conventional biological indicators and a rapid readout biological indicator for flash sterilization