Event Notification Report for October 23, 2023

EN Revision Imported Date: 12/7/2023

EN Revision Text: AGREEMENT STATE REPORT - POSSIBLE DOSE MISADMINISTRATION

The following information was provided by the Kentucky Department for Public Health and Safety, Radiation Health Branch (KY RHB) via email:

"KY RHB was notified on 10/25/23 by the radiation safety officer (RSO) of University of Kentucky (UK) Broad Scope medical license, of an incident which occurred at the UK Chandler Medical Center on October 23, 2023.

"[The UK] RSO reports, 'During a high dose rate (HDR) treatment, the treatment was interrupted due to fluid in the transfer tubing. The authorized user (AU) directed that the transfer tubing be replaced and treatment completed. The tubing used to complete the cycle was not the correct length, resulting in approximately 10 seconds of source exposure at the wrong dwell position(s). The source was outside of the body during this exposure period, therefore, there is uncertainty in the dose estimates to patient skin. Likely exposure in the treatment position (legs apart) is likely below the reporting thresholds in 10 CFR 35, while conservative estimates (assuming patient's legs were closed) lead to doses above reporting thresholds. Since the exact positioning is indeterminant, the licensee did not report a dose from this incident at this time. Upper bound worse case estimates place the skin dose below the level where patient harm is expected by the treating oncologist and no changes in plan of care are anticipated from this event. This incident remains under investigation.'

"RHB is following up with the RSO for additional information not included in the initial report."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The intended organ to be dosed was the cervix/uterus. Dose estimates were not available at the time the report was received from KY RHB.

* * * UPDATE ON 12/6/2023 AT 1904 EST FROM RUSSELL HESTAND TO ERNEST WEST * * *

"On 10/25/2023 the University of Kentucky (UK) reported a possible dose misadministration that occurred at the UK Chandler Medical Center on 10/23/2023. During a high dose rate (HDR) cervix/uterus treatment, the treatment was interrupted due to fluid in the transfer tubing. The authorized user directed that the transfer tubing be replaced, and treatment completed. The tubing used to complete the cycle was not cut to the correct length. This resulted in the source being 12cm out of position for the 10 seconds remaining in the planned treatment. The source was outside of the patient's body during that exposure period, causing a potential radiation exposure to the skin of the thigh in excess of reporting requirements. The worst-case assessment assumes that the patient's thigh was in direct contact with the applicator for the full 10 seconds, resulting in a localized skin dose of 300 cGy. In the judgment of treating physician, the dose is below the level likely to cause injury. However, the dose is above the reporting threshold for a Medical Event. In the most likely scenario, the patient's thigh was at least 8 mm away, resulting in a significantly lower dose of less than 50 cGy. The patient and referring physician were informed in a timely manner.

"Corrective Actions:

"1) A leak mitigation countermeasure is being trialed in an effort to prevent fluid from leaking down the catheter and potentially causing this issue in the future.

"2) Current procedures are very specific about verification of transfer catheter length before starting a treatment. However, they have not until now directly addressed a process for interruption of a procedure to make adjustments to the patient set up. These procedures have been updated and training / education is being performed on the updated processes.

"Based on the investigation by the [Kentucky Department for Public Health and Safety] Radiation Health Branch in collaboration with the University of Kentucky, we find the corrective actions to be sufficient and consider this incident closed."

NMED Item Number: 230461

Notified R1DO (Werkheiser), NMSS Division Director (Williams), and NMSS Event Notifications (Email)

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.

EN Revision Imported Date: 12/27/2023

EN Revision Text: PART 21 REPORT - DEFECT IN VALCOR SOLENOID VALVES

The following is a synopsis of information received via facsimile:

Valcor Engineering Corporation (VEC) identified a defect with Valcor solenoid valves with part number V52600-5890-1 on October 23, 2023. The defect identified is that stroke matching of internal components was not performed in accordance with internal procedures causing valve flow coefficient (Cv) to be only approximately 50 percent of the minimum required Cv of 2. Substantial safety hazard could be created if the flow rate through the solenoid valve exceeded a certain threshold.

VEC has identified two of these solenoid valves at LaSalle County Nuclear Generating Station (LaSalle) with serial numbers 33 and 34.

For corrective actions, VEC repaired and returned the valve with serial number 34 to LaSalle. To prevent recurrence, VEC intends to improve the training program for production personnel and, if needed, review and revise the stroke matching procedure including enhancing quality assurance oversight of that process. VEC estimates it will take 30 days to complete corrective actions.

Currently, LaSalle is the only known affected facility. Valcor is in the process of identifying and notifying affected customers.

For additional information, please contact Mike Swirad, Valcor Engineering Quality Assurance Director (973-467-8400 x 7223), email: mikeswirad@valcor.com