Construction And Application Of Bedding And Clothing Cleaning Up Protocol For Differentiated Thyroid Cancer Patients On ¹³¹I Therapy

Objective:1.To understand the current situation of radiation residual dose rate of bedding and clothing（bed sheet,hospital gown and pillowcase）of patients after¹³¹I treatment,to explore and analyze the influencing factors of radiation residual dose rate of patients’bedding and clothing and its change law with time,and to estimate the cleaning up time of patients’bedding and clothing.2.To construct a cleaning up protocol for patients’bedding and clothing,standardize the cleaning up process of bedding and clothing,and reduce the impact of residual dose rate of bedding and clothing on the surrounding environment,and staff and the public.3.To conduct a clinical empirical study on the cleaning up protocol for¹³¹I treatment of differentiated thyroid cancer patients,and evaluate the effect of the program on the residual dose rate of¹³¹I treatment of differentiated thyroid cancer patients and the time and space cost of bedding and clothing rotation.Methods:1.Analysis of factors influencing the residual dose rate of radiation in the bedding and clothing of patients treated with¹³¹I and determination of the cleaning up time:256patients with differentiated thyroid cancer who were treated with¹³¹I from May to December 2021 in a tertiary care hospital in Taiyuan were selected to accurately monitor the radiation residual dose rate at various points of the patients’clothing using a portable multi-functional radiation detector,and collected the patients’relevant clinical data,combined with the values of the radiation residual dose rate obtained at different time points.The patient’s residual dose rate was collected,and the trend of the residual dose rate of the patient’s bedding and clothing over time was obtained through further curve regression analysis to estimate the cleaning up time of the bedding and clothing.2.Constructing a cleaning up protocol for patients with differentiated thyroid cancer treated with¹³¹I:Based on the results of monitoring the residual dose rate of radiation in the bedding and clothing of 256 patients with differentiated thyroid cancer treated with¹³¹I,combined with the results of literature analysis and semi-structured interviews,we initially constructed a cleaning up protocol for patients with differentiated thyroid cancer treated with¹³¹I,invited 30 experts in the field of nuclear medicine for two rounds of expert consultation,and formed the final draft of the cleaning up protocol for patients with differentiated thyroid cancer treated with¹³¹I by adding,deleting,revising and organizing the entries according to the importance ratings and opinions of the experts on the indicators of the solution in each round.3.Clinical empirical study on the cleaning up protocol of¹³¹I for differentiated thyroid cancer patients:using a historical control design in a classical pilot study,60patients who met the nadir criteria from May to December 2021 were selected as the control group and 60 patients who met the nadir criteria from May to December 2022 were selected as the intervention group in the nuclear medicine department of a tertiary care hospital in Taiyuan City.The control group used the traditional quilt treatment scheme,guided by the GBZ120-2020,and the intervention group implemented the cleaning scheme constructed in this study to compare the radiation residual dose rates at different monitoring sites of the quilt and the time and space costs required for quilt rotation in the 2groups of patients.Results:1.To monitor the residual dose rate of radiation in the bedding and clothing（bed sheet,hospital gown,pillow case）of patients treated with¹³¹I in nuclear medicine through the standard work process of radiation protection.The median residual dose rates of bed sheet,chest,perineum,armpit and pillow-case were 8.59,16.98,14.29,15.83 and 11.82（μSv/h）,χ²=11.427,P<0.05;The residual dose rate of radiation was related to age,education level,iodine intake,thyroid stimulating hormone level,frequency of washing hands,frequency of changing underwear and underlying medical condition（P<0.05）,and was related to time y=b0（b1）t or lny=lnb0+ln（b1）t.2.Based on the results of the analysis of the factors influencing the residual dose rate of the patient’s bedding and clothing radiation,the first draft of the protocol was constructed based on the literature study and the results of semi-structured interviews,including 5 primary indicators,20 secondary indicators and 59 tertiary indicators,and the recall rate of the questionnaires for the 2 rounds of expert consultation was 100%（30/30）.The coefficient of variation of each item in the second round of consultation was 0.00-0.24,the importance score was 4.13-5.00,the expert authority coefficient was 0.867,and the Kendall harmonization coefficients of primary,secondary,and tertiary indicators were0.475,0.420,and 0.292,respectively（P<0.05）,which finally formed the final draft of the¹³¹I treatment for differentiated thyroid cancer patients being cleaned and decontrolled.3.Preliminary application of the clean decontrol protocol for¹³¹I treatment of differentiated thyroid cancer patients in the bedding and clothing,it was found that the residual radiation dose rates at different monitoring sites in the bedding and clothing were significantly lower in the intervention group than in the control group（P<0.05）,and the time cost required for the bedding and clothing rotation was lower in the intervention group（12.76±2.01）d than in the control group（16.47±3.51）d（P<0.001）,The space cost required for rotation in the intervention group（0.92±0.42）m³was significantly lower than that in the control group（1.22±0.31）m³（P<0.001）.Conclusions:1.The patient’s age,education level,iodine intake,thyroid stimulating hormone level,frequency of hand washing,frequency of underwear change and whether the patient was suffering from underlying diseases（cold,incontinence,mobility problems）at the time of hospitalization were the influencing factors of the residual dose rate of the patient’s clothing.The radiation damage to the surrounding environment and the population can be further reduced.2.The cleaning up scheme of¹³¹I for differentiated thyroid cancer patients is scientific、reliable and practical,and the construction process is standardized and rigorous,which can provide guidelines for the cleaning of¹³¹I for differentiated thyroid cancer patients.3.¹³¹I treatment of differentiated thyroid cancer patients with a cleaning up program for quilts can reduce the residual radiation dose rate of bedding and clothing and the time and space costs required for bedding and clothing rotation after patients are discharged from the hospital.