ENS 55192
ENS Event | |
|---|---|
07:00 Apr 9, 2021 | |
| Title | Patient Underdose |
| Event Description | The following information was received from the Washington State Department of Health:
University of Washington broad scope license C001 reported a medical event. The event involves Y-90 microspheres contained in two vials of different activity. Vial A and Vial B were to be delivered to different treatment sites. However, the vials were mixed up and the lower activity vial was delivered to the wrong site, the Authorized User (AU) realized it was the wrong vial and did not inject the second vial. This resulted in an underdose of more than 20 percent. A full report is expected in 15 days and will be forwarded. A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.
The following update is from the report received via e-mail from the Washington State Department of Health: On Friday April 9, 2021, a patient had been prescribed two dosages of yttrium-90 microspheres intended for two different liver treatment sites. One treatment dosage was a larger amount than the other, 35.9 mCi and 21.4 mCi. Both dosages were measured in the Nuclear Medicine CRC 15R dose calibrator prior to use. They were found to be the correctly prescribed amounts and the vials were labelled correctly. Both dosages were transported to the Interventional Radiology suite. When the authorized user (AU) called for the first dosage, the higher of the two activities (35.9 mCi), it was set up and administered, including the required radiation dose rate measurement taken prior to and during the dosing. When the AU called for the second dosage (21.4 mCi), he noticed that the radiation dose rate measurement of the second dosage was higher than it had read for the first administration, which was supposed to be the larger of the two dosages. Realizing that the smaller of the two dosages was mistakenly administered first, the physician stopped the treatment and did not administer the second dosage. It was then confirmed that the patient received the lower of the two dosages (21.4 mCi) to the treatment site that was supposed to receive the higher dosage (35.9 mCi). Nuclear Medicine informed the Environmental Health and Safety Department's (EHS) Medical Health Physicist (MHP), and the MHP subsequently informed the Radiation Safety Officer (RSO). Initially, there were questions regarding the need to evaluate this event as a possible Medical Event. There was uncertainty regarding applying the medical event criteria to both sites together or to each individual site. Additionally, the first treatment site was under-dosed and the AU subsequently had determined that the dose delivered was adequate for that site. After discussing the event with the MHP on Monday morning, April 12, 2021, the RSO requested a meeting with Department of Health (DOH) to discuss the event. The MHP and RSO discussed the event with DOH that afternoon, and DOH informed that it would depend if the written directive included both sites, or if there was a written directive for each site. On Tuesday, April 13, 2021, all the required information was obtained, and the MHP and RSO reviewed the dosage and dose calculations and determined that the medical event criteria was met. The dose delivered is less than prescribed, and will result in no harm to the patient and it is the intention of the physician to treat the second site at some future time. Washington Event Report Number: WA-21-006 |
| Where | |
|---|---|
| University Of Washington Seattle, Washington (NRC Region 4) | |
| License number: | C001 |
| Organization: | Wa Office Of Radiation Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+126.25 h5.26 days <br />0.751 weeks <br />0.173 months <br />) | |
| Opened: | Tristan Hay 13:15 Apr 14, 2021 |
| NRC Officer: | Joanna Bridge |
| Last Updated: | Apr 28, 2021 |
| 55192 - NRC Website | |
University Of Washington with Agreement State | |
WEEKMONTHYEARENS 561932022-10-25T07:00:00025 October 2022 07:00:00
[Table view]Agreement State Leaking Sealed Source ENS 559442022-06-14T07:00:00014 June 2022 07:00:00 Agreement State Agreement State Report - Lost Then Found I-125 Seed ENS 556772021-12-23T08:00:00023 December 2021 08:00:00 Agreement State Underdosing of Patient with YTTRIUM-90 Microspheres ENS 551922021-04-09T07:00:0009 April 2021 07:00:00 Agreement State Patient Underdose ENS 540132019-04-15T07:00:00015 April 2019 07:00:00 Agreement State Agreement State Report - Leaking Intravascular Brachytherapy Device Identified ENS 518792016-04-20T07:00:00020 April 2016 07:00:00 Agreement State Agreement State Report - Missing Static Ionization Source ENS 518492016-03-31T07:00:00031 March 2016 07:00:00 Agreement State Agreement State - Package Containing 40 Millicuries of Ni-63 Reported Missing ENS 511762015-06-19T07:00:00019 June 2015 07:00:00 Agreement State Agreement State Report - Medical Under Dose ENS 495402013-11-12T08:00:00012 November 2013 08:00:00 Agreement State Agreement State Report - Radioactive Material Unaccounted for ENS 469312011-03-31T01:00:00031 March 2011 01:00:00 Agreement State Agreement State Report - Extremity Overexposure During Laboratory Work ENS 411822004-11-05T08:00:0005 November 2004 08:00:00 Agreement State Agreement State Report Due to Loss of Iodine-125 Calibration Seeds 2022-06-14T07:00:00 | |