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Radiological Protection of Patients |
In some cases, especially palliative treatment, the patient may die in the period immediately following the treatment. In such cases, local authorities usually place limits on radioactivity in the body before autopsy, burial or cremation is permitted. The table below is an example of such limits. Local radiation safety authorities must, however, be consulted in each country.
Records of the specifics of radionuclide therapy should be maintained at the hospital and given to the patient along with written precautionary instructions.
In the case of death of a patient within a few months of therapy, it is advisable that the hospital where the patient received treatment, or a radiation protection specialist, be contacted to determine what (if any) precautions are necessary to meet national regulations.
| Radionuclide | Autopsy/Embalming MBq) | Burial (MBq) | Cremation (MBq) |
| Phosphorus-32 | 100 | 2000 | 30 |
| Strontium-89 | 50 | 2000 | 20 |
| Yttrium-90 | 200 | 2000 | 70 |
| Iodine-131 | 10 | 400 | 400 |
Current international security measures such as those in place at airports and border crossing points may include extremely sensitive radiation detectors. It is quite possible that patients treated with gamma-emitting radionuclides could trigger these alarms, particularly in the period immediately following discharge. Triggering of an alarm does not mean that the patient is emitting dangerous levels of radiation - the detectors are designed to detect levels of radioactivity far below those of concern to human health. For example, it is possible to detect 0.01 MBq of iodine-131 at a distance of 2-3 m. This is a tiny fraction of the recommended discharge level in a patient.
The security authorities are well aware of this possibility, and if a patient is likely to travel soon after discharge, the hospital or the patient's doctor should provide a written statement of the therapy and radionuclide used for the patient to carry with him. The security staff are, however, unlikely to have any training for this occurrence, so patients should be advised to avoid such travel unless they are willing to experience some inconvenience.
A patient was referred for treatment of Graves' disease with 555 MBq of iodine-131. The radiopharmacist assumed that the dosage to be delivered was 1073 MBq rather than 555 MBq, since a 1073 MBq dose was routinely used for Graves' disease in that hospital. Therefore, he requested a 1073 MBq activity from a commercial radiopharmacy. The activity received was 1058 MBq, labeled as such. When the radiopharmacist logged the dosage into the computer after it had been measured by an activity meter (often called dose calibrator), he failed to take note of the activity of 550 MBq in the referring physician's prescription. In addition, the physician who administered the isotope did not check the prescription. As a result, the patient's thyroid received about 319 Gy instead of the intended 167 Gy, an overdose of 91%.