A combination of well-known safety procedures could prevent most patient-harming errors in radiation therapy, according to a study presented at the annual meeting of the American Association of Physicists in Medicine (AAPM) and Canadian Organization of Medical Physicists, July 31 to Aug. 4 in Vancouver, Canada.
Radiation oncologists use more than a dozen quality assurance (QA) checks to prevent radiotherapy errors, but until now, no one has systematically evaluated their effectiveness, according to researchers from Johns Hopkins University School of Medicine in Baltimore.
Working with researchers at Washington University in St. Louis, the Johns Hopkins team gathered data on 4,000 near miss events that occurred from 2008 to 2010 at the two institutions. They then narrowed the dataset to 290 events in which errors occurred that—if they had not been caught in time—could have resulted in serious harm to patients. For each commonly used QA check, they determined the percentage of these potential patient-harming incidents that could have been prevented.
The group’s key finding was that a combination of common QA measures would have prevented more than 90 percent of the potential incidents.
“While clinicians in this field may be familiar with these quality assurance procedures, they may not have appreciated how effective they are in combination,” Eric C. Ford, PhD, assistant professor of radiation oncology and molecular radiation sciences at Johns Hopkins, said.
The steps include:
- In vivo portal dosimetry via an Electronic Portal Imaging Device (EPID). EPIDs built in to many radiotherapy-delivery systems can provide real-time x-ray-like images of the radiation dose to be delivered to the patient. But Ford said less than 1 percent of radiotherapy clinics use EPIDs because the software and training needed to operate them are mostly absent.
- Physician checklist. Ford said their research showed that another key to safety turned out to be a humble checklist of relatively low-tech measures, “assuming it’s used consistently correctly, which it often isn’t.” Physicians should review the patient chart before treatment, Ford stated.
- Radiation therapist checklist. Similar to the physician, the radiation physicist also should complete a checklist of the plan prior to treatment.
- Dose measurements. Use film-based radiation-dose measurements as an alternative to EPID.
- Mandatory timeout. The radiation therapist should conduct a timeout before radiation is turned on to double-check that the written treatment plan and doses match what’s on the systems. This step includes checking the patient’s identification and set-up and reviewing laterality.
Ford and colleagues proposed a national radiotherapy incident reporting system, which would have treatment errors and near-misses reported and sent to a central group for evaluation and dissemination to clinics. “It could work in ways similar to how air and train accidents are reported to the National Transportation Safety Board,” he noted.