Evaluation of Sterilization Indicators in the Central Sterile Supply Department

Background: The Central Sterile Supply Department (CSSD) is a critical hospital support service responsible for cleaning, packaging, sterilizing, storing, and distributing reusable medical devices. Effective sterilization is essential for preventing healthcare-associated infections (HAIs). Sterilization indicators, including mechanical, chemical, and biological indicators, are important quality-assurance tools used to assess whether sterilization cycles achieve the required conditions. Aim: To evaluate the performance of sterilization indicators used in the CSSD and assess compliance with recommended sterilization-monitoring practices. Methods: A prospective observational study was conducted in the CSSD of Lokmanya Tilak Municipal & General Hospital, Sion, Mumbai. A total of 200 sterilization cycles were monitored using mechanical cycle records, external and internal chemical indicators (CIs), Bowie-Dick-type air-removal tests, and biological indicators (BIs). Data were recorded using a structured proforma and analyzed using descriptive statistics. Indicator results were compared with sterilizer cycle parameters and institutional sterilization-monitoring protocols. Results: Of the 200 sterilization cycles evaluated, 188 cycles (94.0%) showed satisfactory mechanical parameters. External chemical indicators showed an acceptable colour change in 194 cycles (97.0%), while internal chemical indicators were acceptable in 186 cycles (93.0%). Bowie-Dick tests were satisfactory in 58 of 60 tests (96.7%). Biological indicators showed growth in 2 cycles (1.0%), indicating sterilization failure or a need for corrective action. The most common causes of indicator failure were improper loading, packaging defects, inadequate steam penetration, and operator error. Conclusion: The study highlights the importance of a combined monitoring approach using mechanical, chemical, and biological indicators. Chemical indicators provide immediate information about exposure to sterilization conditions, whereas biological indicators provide direct evidence of microbial lethality. Regular training, preventive maintenance, documentation, and adherence to standard operating procedures are essential for reliable sterilization and patient safety..