[Subcontracting a steam sterilization activity: Impact on surgical instruments].

Area of Science:

• Materials Science
• Medical Device Sterilization
• Corrosion Engineering

Background:

• Subcontracting sterilization led to an automated cleaning facility.
• Resterilizable stainless steel needle holders exhibited abnormal corrosion post-implementation.

Purpose of the Study:

• Investigate the root causes of stainless steel needle holder corrosion.
• Optimize the sterilization circuit to prevent future corrosion incidents.

Main Methods:

• Comprehensive sterilization process mapping.
• Ishikawa (fishbone) diagram for cause identification.
• Analysis of intrinsic (steel quality) and extrinsic factors (water quality, passivation, soaking).
• Real-world testing of needle holder kits under varied conditions.

Main Results:

• Needle holder steel grade met medical standards; passivation and pre-processing were not causal factors.
• Prolonged soaking times and the use of softened rinsing water (higher chloride content) were identified as key contributors to corrosion.
• Corrosion inhibitors proved ineffective or incompatible.
• Switching to reverse osmosis water and implementing dynamic drying significantly reduced corrosion incidence.

Conclusions:

• Optimized water quality (reverse osmosis) and dynamic drying are crucial for preventing corrosion in automated sterilization.
• Minimizing waiting times and auditing sterilization processes before outsourcing are essential.
• Clear management guidelines for sterilization outsourcing are recommended to prevent such issues.