Impact of sweating on equivalent dose of patients treated with ¹³¹Iiodine

Abstract

Background:Radioiodine therapy is used for the treatment of patients with differentiated thyroid cancer (DTC) who undergo total thyroidectomy. After radioiodine administration, regulations require to quarantine these patients until their retained activity reduces to <33 mCi. Some of the injected radioiodine is excreted by perspiration which helps dose reduction so that performing the activities which stimulate sweating such as exercise may shorten the time of dose reduction. To the best of our knowledge, this is the first study in the literature that has evaluated the impact of specific exercise program on the ambient equivalent dose of 131I gamma rays.Materials and Methods:Patients with DTC without metastasis who had undergone total thyroidectomy and were treated with radioiodine were included in this study. 30 patients were chosen among patients who were able to exercise, did not have renal failure, and did not use diuretics. Patients were divided into two control and intervention groups. Intervention group members walked on treadmills under a specific program, in 3 time intervals. The control group did not have any specific activity. Immediately after each exercise process, both groups took a shower, and their doses were measured by a survey dosimeter.Results:It was revealed that there was a significant difference between mean values before and after each exercise time. The calculated P value which evaluates the overall impact was 0.939 which revealed that there was no significant difference between total ambient equivalent dose reductions of both groups.Conclusion:According to the study, it may conclude that sweating is an effective alternative way for radioiodine excretion, and if sweating is accompanied with well-hydrated status they may have synergism effect to shorten quarantine period. This could be an important consideration in patients which over-hydration is intolerable especially those with cardiac, liver, or renal problems.

Autosomal dominant polycystic kidney disease: a potential mistake in the interpretation of radioiodine whole-body scintigraphy

“…Many potential errors in radionuclide scintigraphy could occur and reporting should be done with caution [3] , [4] . Because of the harmful effects of radioiodine [8] , [9] , recognition of potential false-positive 131 I scintigraphy is critical to avoid renewal therapeutic doses of radioactive iodine.…”

The minimum amount of fluids needed to achieve the fastest time to reach permissible level for release in well-differentiated thyroid patients undergoing high-dose I-131 therapy

“…showed sweating may help promote excretion of 131-I but in our center, the patients are not subjected to similar stress to elicit sweating. [ 11 ] The loss of I-131 via sweating due to humidity was not addressed in this study. However, the cool environment (approximately 297 K [24°C]) in the air-conditioned isolation rooms reduces sweating.…”