Introduction In the pharmaceutical industry, Out-of-Specification (OOS) events can have significant consequences, impacting product quality, patient safety, and regulatory compliance. Effective OOS investigation is crucial to identify the root causes, implement corrective actions, and prevent future occurrences. This blog post will explore various tools and techniques employed in OOS investigations. Essential Tools for OOS Investigations Data Analysis Tools: Statistical Software: Leverage software like Minitab, Excel, or specialized statistical packages for data analysis, trend identification, outlier detection, and process variability assessment. Quality Management Systems (QMS): Utilize QMS software to centralize and manage quality data, facilitating efficient data retrieval, analysis, and reporting during investigations. Electronic Batch Records (EBR): Employ EBR systems to capture and store detailed manufacturing process information, aiding in tracing back steps, identifyi...
For evaluation of steam sterilizer penetration efficiency, a Bowie dick-test is performed. It means to how much extent the steam will penetrate into the load to eliminate air entrapped into the load. Satisfactory Bowie dick determines the effective removal of air removal from the steam sterilizer.
Normally, the bowie-dick test is a routine challenge test of autoclave, wherein daily before sterilization of load, Bowie dick and leak test are performed. The test ensures that the steam sterilizer penetration is optimum, and bioload can be sterilized. The bowie-dick test is also called a dynamic air removal test.
Why Bowie dick test is required?
This test is performed to evaluate the porous load. An example of a porous load is garment load. For the test,bowie-dick test packs are used. If the test packs color changes to black, then the cycle is successful, and if slight color change or no change in color, then the cycle is unsuccessful. The photograph is attached below.
Bowie Dick Test Pack
Steam sterilizer is an essential part of the sterile pharmaceutical industry. For a sterile drug manufacturing plant, sterility is a major concern, and all the way sterility has to be maintained for all products during their shelf life.
Hence for evaluation steam sterilizers, penetration power the bowie dicktest is being conducted with a bowie dick test pack.
In 1963, Dr. J. Bowie and Dr. J. Dick performed the dynamic air removal study from the steam sterilizer. They used towels packs for the evaluation of the test pack. He stacked paper pasted with a chemical indicator in between towels.
In 1970, the modification to huchback towel configuration was changed to 100% cotton surgical towels. However, in late 1980, the AAMI introduced the first standardized description of the dynamic air removal test pack naming the Bowie-Dick test pack.
For a detailed history of Bowie dick test pack creation, go to the below link.
Which chemical indicator is used in the Bowie dick test pack?
Bismuth III is a type II chemical indicatorthat is used for Bowie dick test pack preparation. The composition of any one of claims 1 through 6, wherein when exposed to a first condition selected from the group consisting of steam at a temperature of 1340C for 2 minutes and steam at a temperature of 1210C for 10 minutes, the composition changes color to brown or black.
Where to keep Bowie dick test pack in steam sterilizer?
The Bowie dick test pack has to be kept at the geometrical center of the autoclave. A detailed demonstration has been given in the below picture. Normally the test pack contains 13 blank sheets below and above the Bowie dick test pack.
Bowie Dick Test Pack Location
This test pack has to be kept in an empty load for evaluation. At 121℃ only 10 minutes of sterile hold is required to penetrate in to load. If within 10 minutes the indicator changes the color to complete black, the autoclave is good for routine use. And at 134℃ only 4 minutes of hold is required.
When to perform Bowie dick test?
Daily before taking actual sterilization load.
Usually, a preheat-up cycle is required to heat the steam sterilizer. f the autoclave use s continues then a heat up cycle is not required.
An autoclave bowie dick test is performed to evaluate the penetration efficiency of steam into the load. The successful bowie-dick test represents the efficient penetration of steam into loads. Steam penetration is a much more important criterion for the porous load. Hence bowie dick test is mandatory for autoclave.
Reference:
1. Association for the Advancement of Medical Instrumentation (AAMI)'s ANSI/AAMI Comprehensive Guide to Steam Sterilization and Sterility Assurance in Health Care Facilities, ST79:2010, & A1:2010, & A2:2011, & A3:2012, & A4:2013 2. Chemical indicator composition, indicators, and methods
Very good information
ReplyDeleteExplained the concept in a very comprehensive manner. Thank you Prashant Sir
ReplyDeleteThank you for reading the post.
DeleteUseful information
ReplyDeleteVery helpful information for me..as i am working with steam sterilizer(autoclave)
ReplyDeleteGood information
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