Taxonometric applications in radiotherapy incident analysis

Safety culture to improve accidental event reporting in radiotherapy

BACKGROUND AND PURPOSE

The potential for unintended and adverse radiation exposure in radiotherapy (RT) is real and should be studied because RT is a highly complex, multistep process, which requires input from numerous individuals from different areas and steps of the RT workflow. The 'Incident' (I) is an event the consequence of which is not negligible from the point of view of protection or safety. A 'near miss' (NM) is defined as an event that is highly likely to happen but did not occur. The purpose of this work is to show that through systematic reporting and analysis of these adverse events, their occurrence can be reduced.

MATERIALS AND METHODS

Staff were trained to report every type of unintended and adverse radiation exposure and to provide a full description of it.

RESULTS

By 2018, 110 worksheets had been collected, with an average of 6.1 adverse events per year (with 780 patients treated per year, meaning an average incident rate of 0.78%). In 2001-2009, 37 events were registered (13 I and 24 NM), the majority of them were in the decision phase (12/37), while in 2010-2013, there were 42 (1 I and 41 NM) in both the dose-calculation and transfer phase (19/42). In 2014-2018, 31 events (1 I and 30 NM) were equally distributed across the phases of the RT process. In 9/15 cases of I, some checkpoint was introduced.

CONCLUSION

The complexity of the RT workflow is prone to errors, and this must be taken into account by encouraging a safety culture. The aim of this paper is to present the collected incidents and near misses and to show how organization and practice were modified by the acquired knowledge.

Clinical implementation, logistics and workflow guide for MRI image based interstitial HDR brachytherapy for gynecological cancers

Interstitial brachytherapy (IBT) is often utilized to treat women with bulky endometrial or cervical cancers not amendable to intracavitary treatments. A modern trend in IBT is the utilization of magnetic resonance imaging (MRI) with a high dose rate (HDR) afterloader for conformal 3D image-based treatments. The challenging part of this procedure is to properly complete many sequenced and co-related physics preparations. We presented the physics preparations and clinical workflow required for implementing MRI-based HDR IBT (MRI-HDR-IBT) of gynecologic cancer patients in a high-volume brachytherapy center. The present document is designed to focus on the clinical steps required from a physicist's standpoint. Those steps include: (a) testing IBT equipment with MRI scanner, (b) preparation of templates and catheters, (c) preparation of MRI line markers, (d) acquisition, importation and registration of MRI images, (e) development of treatment plans and (f) treatment evaluation and documentation. The checklists of imaging acquisition, registration and plan development are also presented. Based on the TG-100 recommendations, a workflow chart, a fault tree analysis and an error-solution table listing the speculated errors and solutions of each step are provided. Our workflow and practice indicated the MRI-HDR-IBT is achievable in most radiation oncology clinics if the following equipment is available: MRI scanner, CT (computed tomography) scanner, MRI/CT compatible templates and applicators, MRI line markers, HDR afterloader and a brachytherapy treatment planning system capable of utilizing MRI images. The OR/procedure room availability and anesthesiology support are also important. The techniques and approaches adopted from the GEC-ESTRO (Groupe Européen de Curiethérapie - European Society for Therapeutic Radiology and Oncology) recommendations and other publications are proven to be feasible. The MRI-HDR-IBT program can be developed over time and progressively validated through clinical experience, this document is expected to serve as a reference workflow guideline for implementing and performing the procedure.

Patient safety in external beam radiotherapy, results of the ACCIRAD project: Recommendations for radiotherapy institutions and national authorities on assessing risks and analysing adverse error-events and near misses

The ACCIRAD project, commissioned by the European Commission (EC) to develop guidelines for risk analysis of accidental and unintended exposures in external beam radiotherapy (EBRT), was completed in the year 2014. In 2015, the "General guidelines on risk management in external beam radiotherapy" were published as EC report Radiation Protection (RP)-181. The present document is the third and final report of the findings from the ACCIRAD project. The main aim of this paper is to describe the key features of the risk management process and to provide general guidelines for radiotherapy departments and national authorities on risk assessment and analysis of adverse error-events and near misses. The recommendations provided here and in EC report RP-181 are aimed at promoting the harmonisation of risk management systems across Europe, improving patient safety, and enabling more reliable inter-country comparisons.

The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management

The increasing complexity of modern radiation therapy planning and delivery challenges traditional prescriptive quality management (QM) methods, such as many of those included in guidelines published by organizations such as the AAPM, ASTRO, ACR, ESTRO, and IAEA. These prescriptive guidelines have traditionally focused on monitoring all aspects of the functional performance of radiotherapy (RT) equipment by comparing parameters against tolerances set at strict but achievable values. Many errors that occur in radiation oncology are not due to failures in devices and software; rather they are failures in workflow and process. A systematic understanding of the likelihood and clinical impact of possible failures throughout a course of radiotherapy is needed to direct limit QM resources efficiently to produce maximum safety and quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and has developed a framework for designing QM activities, based on estimates of the probability of identified failures and their clinical outcome through the RT planning and delivery process. The Task Group has chosen a specific radiotherapy process required for "intensity modulated radiation therapy (IMRT)" as a case study. The goal of this work is to apply modern risk-based analysis techniques to this complex RT process in order to demonstrate to the RT community that such techniques may help identify more effective and efficient ways to enhance the safety and quality of our treatment processes. The task group generated by consensus an example quality management program strategy for the IMRT process performed at the institution of one of the authors. This report describes the methodology and nomenclature developed, presents the process maps, FMEAs, fault trees, and QM programs developed, and makes suggestions on how this information could be used in the clinic. The development and implementation of risk-assessment techniques will make radiation therapy safer and more efficient.

Patient safety in external beam radiotherapy - guidelines on risk assessment and analysis of adverse error-events and near misses: introducing the ACCIRAD project

In 2011 the European Commission launched a tender to develop guidelines for risk analysis of accidental and unintended exposures in external beam radiotherapy. This tender was awarded to a consortium of 6 institutions, including the ESTRO, in late 2011. The project, denominated "ACCIRAD", recently finished the data collection phase. Data were collected by surveys administered in 38 European countries. Results indicate non-uniform implementation of event registration and classification, as well as incomplete or zero implementation of risk assessment and events analysis. Based on the survey results and analysis thereof, project leaders are currently drafting proposed guidelines entitled "Guidelines for patient safety in external beam radiotherapy - Guidelines on risk assessment and analysis of adverse-error events and near misses". The present article describes the aims and current status of the project, including results of the surveys.

A Practice-based Taxonomy for Radiation Treatment Errors

PURPOSE

An absence of a common language for incident classification limits knowledge sharing within and between organizations in the radiotherapy community. This challenge provided the motivation to develop a clinically relevant taxonomy for radiotherapy errors.

MATERIALS AND METHODS

This was a multicenter, prospective study that consisted of three phases: (1) an initial version of the taxonomy was developed based on the World Health Organization Conceptual Framework for the International Classification for Patient Safety and taxonomy models from radiotherapy and other industries; (2) the taxonomy was evaluated using actual incident data from a single practitioner and revised; and (3) face validity testing of the taxonomy was performed by two additional practitioners from different radiotherapy centers using simulated incident cases.

RESULTS

The taxonomy consisted of seven classes: incident nature, impact, incident type, stage of origin, stage of discovery, contributing factors, and preventative strategies. Each class was divided into subcategories containing increasingly detailed information. A total of 191 consecutive incidents were classified in phase 2 to ensure no further revision to the taxonomy was required. In phase 3, low interobserver agreement (<60%) was obtained for most classes of the taxonomy in the first face validity test. After revisions were made to the taxonomy based on practitioners' feedback, a second face validity test yielded a high degree of agreement (70%-93%) for all classes.

CONCLUSIONS

Our multiphase, iterative approach has yielded a workable and multidimensional set of incident classifiers that can be scaled to accommodate local, regional and discipline-specific requirements. Opportunities exist to implement this taxonomy in institutional and national incident databases to facilitate incident learning within and between institutions.

Collection and evaluation of incidents in a radiotherapy department : a reactive risk analysis

PURPOSE

to report on the use of an internal system for incident reporting.

PATIENTS AND METHODS

from October 2001 until June 2009, data on incidents were collected in the radiotherapy department (RT) by means of an incident reporting worksheet. The risk analysis was based on the US Navy method of mishap cause investigation, the Human Factors Analysis and Classification System (HFACS).

RESULTS

37 incidents over 5,635 treatments were collected. Of the incidents, 20 involved deviation of the dose to the patient; only 6 showed clinical evidence of overdosage, while 2 of them showed permanent evidence of overdosage. There were 24 incidents that were classified as near misses (NM). Incorrect data input and use of an incorrect treatment field were the most common causes of the registered incidents. Reactive risk analysis showed how skill-based errors were associated with attention failure at the unsafe act level. Dose prescription and dose calculation are the most critical phases of the entire process. Most of the errors were discovered in set-up/treatment and during treatment visit/follow-up phases. The highest number of correction procedures was necessary in the phases of dose prescription and dose calculation.

CONCLUSION

collecting and analyzing internal incidents improves the operative procedures used in the department.

Quality assurance needs for modern image-based radiotherapy: recommendations from 2007 interorganizational symposium on "quality assurance of radiation therapy: challenges of advanced technology"

This report summarizes the consensus findings and recommendations emerging from 2007 Symposium, "Quality Assurance of Radiation Therapy: Challenges of Advanced Technology." The Symposium was held in Dallas February 20-22, 2007. The 3-day program, which was sponsored jointly by the American Society for Therapeutic Radiology and Oncology (ASTRO), American Association of Physicists in Medicine (AAPM), and National Cancer Institute (NCI), included >40 invited speakers from the radiation oncology and industrial engineering/human factor communities and attracted nearly 350 attendees, mostly medical physicists. A summary of the major findings follows. The current process of developing consensus recommendations for prescriptive quality assurance (QA) tests remains valid for many of the devices and software systems used in modern radiotherapy (RT), although for some technologies, QA guidance is incomplete or out of date. The current approach to QA does not seem feasible for image-based planning, image-guided therapies, or computer-controlled therapy. In these areas, additional scientific investigation and innovative approaches are needed to manage risk and mitigate errors, including a better balance between mitigating the risk of catastrophic error and maintaining treatment quality, complimenting the current device-centered QA perspective by a more process-centered approach, and broadening community participation in QA guidance formulation and implementation. Industrial engineers and human factor experts can make significant contributions toward advancing a broader, more process-oriented, risk-based formulation of RT QA. Healthcare administrators need to appropriately increase personnel and ancillary equipment resources, as well as capital resources, when new advanced technology RT modalities are implemented. The pace of formalizing clinical physics training must rapidly increase to provide an adequately trained physics workforce for advanced technology RT. The specific recommendations of the Symposium included the following. First, the AAPM, in cooperation with other advisory bodies, should undertake a systematic program to update conventional QA guidance using available risk-assessment methods. Second, the AAPM advanced technology RT Task Groups should better balance clinical process vs. device operation aspects--encouraging greater levels of multidisciplinary participation such as industrial engineering consultants and use-risk assessment and process-flow techniques. Third, ASTRO should form a multidisciplinary subcommittee, consisting of physician, physicist, vendor, and industrial engineering representatives, to better address modern RT quality management and QA needs. Finally, government and private entities committed to improved healthcare quality and safety should support research directed toward addressing QA problems in image-guided therapies.