Background: The Sterile Production Centre (SPC) at the Princess Alexandra Hospital (PAH) manufactures approximately 7660 medicines each year, mainly cancer medicines, including trials. Errors in compounding have the potential to lead to death or disability. The importance of studying working conditions to identify potential human failures (or latent errors) in order to be remedied, has been emphasised by the theorist, Reason1. Standard Operating Procedures (SOPs) as well as Australian and international guidelines are in place to decrease the likelihood of human error occurring.2-4
Aims: To identify any latent errors in compounding at the PAH’s SPC, and if so, to inform the review of and compliance to, SOPs.
Methods: An observational study of 50 compounded medicines between March 4 to 15 2019 was carried out. An audit tool was created based on reported latent errors from a 2018 human factors-based Canadian study.5 The audit tool consisted of criteria in the four broad compounding steps of transcription, setting up, verification/reconstitution/mixing drug into the final container, and final check in SPC.
Results: No known actual errors occurred. In total, 50 latent errors were observed across 9 out of 23 latent error types. Three latent error types were observed, that to our knowledge, are not published in the literature- no independent second check of recorded batch number and expiry dates on batch sheet, no batch number and expiry recorded for partially used mixes, and no time check and immediate recording of the time product was prepared (particularly important for short expiry medicines).
Conclusion: Local SOPs and batch sheets have been revised to incorporate more detail, such as the requirement to sign for independent second checks. Regular education about the importance of completing all documentation has been implemented. A post-implementation audit will be carried out in the near future to evaluate interventions.