Critical Re-Evaluation of a Failure Mode Effect Analysis in a Radiation Therapy Department After 10 Years

Failure mode effect analysis (FMEA) is a proactive methodology that allows one to analyze a process, regardless of whether an adverse event occurs. In our radiation therapy (RT) department, a first FMEA was performed in 2009. In this paper we critically re-evaluate the RT process after 10 years and present it in terms of a lesson learned.

A working group (WG), led by a qualified clinical risk engineer, which included radiation oncologists, physicists, a radiation therapist, and a nurse, evaluated the possible failure modes (FMs) of the RT process. For each FM, the estimated frequency of occurrence (O, range 1-4), the expected severity of the damage (S, range 1-5), and the detectability lack (D, range 1-4) were scored. A risk priority number (RPN) was obtained as RPN = OxSxD. The data were compared with the 2009 edition.

In the 2020 analysis, 67 FMs were identified (27 in the 2009 series). The absolute risk values of the previous 3 highest FMs were generally reduced. The patient identification risk (highest value in the 2009 analysis) was reduced from 48.0 to 6.9, becoming the 51st RPN score, thanks to a patient barcode recognition within the bunker. The 2020 highest risk values regarded: (i-2020) the patient's inadequate recollection and reporting of his/her medical history (ie, anamnesis) during the first medical examination and (ii-2020) the incorrect interpretation of tumor and normal tissue in computed tomography images. The WG proposed corrective actions.

In this single institution experience, the 10-year FMEA analysis showed a reduction in the previous higher RPN values thanks to the corrective actions taken. The new FMs and subsequent RPNs reveal the need for a continuous iterative improvement process.