Susan Lentz

A failure modes and effects analysis study for gynecologic high-dose-rate brachytherapy

PURPOSE To improve the quality of our gynecologic brachytherapy practice and reduce reportable events, we performed a process analysis after the failure modes and effects analysis (FMEA). METHODS AND MATERIALS The FMEA included a multidisciplinary team specifically targeting the tandem and ring brachytherapy procedure. The treatment process was divided into six subprocesses and failure modes (FMs). A scoring guideline was developed based on published FMEA studies and assigned through team consensus. FMs were ranked according to overall and severity scores. FM ranking >5% of the highest risk priority number (RPN) score was selected for in-depth analysis. The efficiency of each existing quality assurance to detect each FM was analyzed. RESULTS We identified 170 FMs, and 99 were scored. RPN scores ranged from 1 to 192. Of the 13 highest-ranking FMs with RPN scores >80, half had severity scores of 8 or 9, with no mode having severity of 10. Of these FM, the originating process steps were simulation (5), treatment planning (5), treatment delivery (2), and insertion (1). Our high-ranking FM focused on communication and the potential for applicator movement. Evaluation of the efficiency and the comprehensiveness of our quality assurance program showed coverage of all but three of the top 49 FMs ranked by RPN. CONCLUSIONS This is the first reported FMEA process for a comprehensive gynecologic brachytherapy procedure overview. We were able to identify FMs that could potentially and severely impact the patients treatment. We continue to adjust our quality assurance program based on the results of our FMEA analysis.

SU‐C‐137‐02: A Failure Mode and Effects Analysis for Tandem and Ring Brachytherapy

PURPOSE To improve the quality and safety of our tandem and ring brachytherapy practice and procedure, we performed a treatment process analysis following the failure modes and effects analysis (FMEA) method. METHODS The FMEA analysis was performed by a multi-disciplinary team. The treatment process was divided into six sub-processes and a flowchart was created for each. For each action point within a sub-process, failure modes (FM) were collected. A scoring guideline was developed based on published FMEA studies and adapted for brachytherapy at UC Davis. Scores were assigned through team consensus. FM were ranked according to overall score as well as severity score alone. FM ranking above 5% of the highest risk priority number (RPN) score, representing half the FM, were selected for in-depth analysis. The efficiency of each existing QA process to detect FM and the number of QA tests in place for each FM were analyzed. RESULTS 96 FM were scored for severity, occurrence and detectability. RPN scores ranged from 1 to 192. Of the 12 highest ranking FM with RPN scores > 80, half had severity scores of 8 or 9, with no mode having severity of 10. Of the top 48 FM, the originating process steps were insertion (10%), simulation (33%), planning (29%) and delivery (25%). Checklist efficiency and comprehensiveness including physician, nurse and physics checks, ranged from 25% to 79% in preventing the top 48 FM ranked by RPN. Physics machine QA was inefficient in detecting the top ranked FM (<5%), but was very efficient to catch FM with severity >7 (15%). CONCLUSION This is the first reported FMEA process in gynecologic brachytherapy. We were able to identify failure modes that could potentially and severely impact the patients treatment. We continue to adjust our QA program based on the results of our FMEA analysis.