Radiation Protection in Radiotherapy Part 16 Discharge of Patients IAEA Training Material on Radiation Protection in Radiotherapy

Radiation Protection in RadiotherapyPart 16: Discharge of patients2 Discharge of patients From a radiation safety perspective an issue... l l If patients are discharged with radioactive sources remaining in the patient after a temporary implant - this is a severe accident l l If a permanent radioactive implants are in place - others need to know about it l l If the patient has been treated with unsealed radioactive isotopes (e.g. 131-I, 89-Sr) - NOT subject of this course but covered in the companion course on nuclear medicine

Radiation Protection in RadiotherapyPart 16: Discharge of patients3 Advice from BSS appendix II.28. l “In order to restrict the exposure of any members of the household of a patient who has undergone a therapeutic procedure with sealed or unsealed radionuclides and members of the public, such a patient shall not be discharged from hospital before the activity of radioactive substances in the body falls below the level specified in Schedule III, Table III-VI. Written instructions to the patient concerning contact with other persons and relevant precautions for radiation protection shall be provided as necessary”.

Radiation Protection in RadiotherapyPart 16: Discharge of patients4 Objectives l To appreciate the need for checks of patients before discharge after radioactive implants l To understand the need to impose limit values for the discharge of patient l To be familiar with the conditions for discharge of patients with radioactive implants l To be able to provide patients, clinicians and others with advice regarding the radiation safety of the implant.

Radiation Protection in RadiotherapyPart 16: Discharge of patients5 Content 1. Monitoring of patients after temporary implants 2. Discharge rules for patients with permanent implants 3. Information for persons in contact with patients who are discharged with permanent implants

Radiation Protection in RadiotherapyPart 16: Discharge of patients6 1. Monitoring of patients after temporary implants l If the implant is temporary, one MUST ensure that all sources are removed from the patient prior to discharge l This applies to all isotopes and all types of implants including HDR and LDR remote afterloading l All brachytherapy patients should be monitored before discharge

Radiation Protection in RadiotherapyPart 16: Discharge of patients7 Measurement objective l Dose rate at 1m distance from the patient 1m

Radiation Protection in RadiotherapyPart 16: Discharge of patients8 Potential for severe accidents An example due to equipment design: l Sources were dislodged from the drive mechanism of an HDR remote afterloading machine and remained in the patient; she died from radiation l There were many contributing factors, such as: n Equipment seemed not sufficiently tested n Conflicting signals of indicator for source position n History of malfunction of a detector l However, in any case the accident could have been prevented if appropriate patient monitoring would have been in place

Radiation Protection in RadiotherapyPart 16: Discharge of patients9 What needs to be established: l Appropriate procedures in writing l An appropriately trained medical physicist and/or RSO must be involved in the treatment l A monitor at the door of brachytherapy treatment rooms in the ward should be available l A portable radiation monitor available for check of the patient prior to discharge

Radiation Protection in RadiotherapyPart 16: Discharge of patients10 Appropriate monitoring l Requires trained personal l Knowledge of the sources used l Knowledge of the implant type Radioactive source

Radiation Protection in RadiotherapyPart 16: Discharge of patients11 Brachytherapy with sealed sources l Area monitor helps to monitor presence of radioactive sources l Typically there is no hazard from contamination of linen (however, for seed implants watch for lost seeds)

Radiation Protection in RadiotherapyPart 16: Discharge of patients12 2. Permanent radioactive implants l Short half life: 198-Au seeds l Most common: 125-I seed for prostate implants l Increasingly popular: 103-Pd (palladium) seeds for prostate implants l (Not considered here: radioactive stents for prevention of restenosis in blood vessels (typically 32-P)) Mentor

Radiation Protection in RadiotherapyPart 16: Discharge of patients13 Characteristics of the isotopes

Radiation Protection in RadiotherapyPart 16: Discharge of patients14 Risks: l Dislocation of sources l Irradiation of other persons in contact with the patient l Irradiation of persons in case of a medical emergency involving the patient l Irradiation of persons after the patient’s death

Radiation Protection in RadiotherapyPart 16: Discharge of patients15 IAEA BSS (1996) App. II.28 l “In order to restrict the exposure of any member of the household of a patient who has undergone a therapeutic procedure with sealed or unsealed radionuclides and members of the general public, such a patient shall not be discharged from hospital before the activity of the radioactive substances in the body falls below the level specified in Schedule III.”

Radiation Protection in RadiotherapyPart 16: Discharge of patients16 IAEA BSS (1996) App. II.28 l BSS Schedule III, Table III-VI: Guidance level only given for 131-I: Maximum activity for discharge 1100MBq l Other isotopes not mentioned l Legal limit values are still applicable

Radiation Protection in RadiotherapyPart 16: Discharge of patients17 Legal limit values l May vary from state to state l May not be available for the isotope of interest… l However, limit values should be established by each facility using professional judgement if no regulatory guidance is available

Radiation Protection in RadiotherapyPart 16: Discharge of patients18 Example for limit values in Australia

Radiation Protection in RadiotherapyPart 16: Discharge of patients19 Discharge rules l In addition to the limit values for activity within the patient other discharge rules may be established. Examples are: n Maximum dose rate at different distances of the patient n Likelihood of dislocation of sources n Consideration of the performance and mental status of the patient

Radiation Protection in RadiotherapyPart 16: Discharge of patients20 A set of typical discharge rules:

Radiation Protection in RadiotherapyPart 16: Discharge of patients21 3. Advice to patients: l IAEA BSS (1996) App. II.28: l “Written instructions to the patient concerning contact with other persons and relevant precautions for radiation protection shall be provided as necessary.”

Radiation Protection in RadiotherapyPart 16: Discharge of patients22 Advice to patients: l Must be in writing l Easy to understand l May require translation in other languages l Should be discussed with the patient l Should contain contact details for clinical and radiation protection staff

Radiation Protection in RadiotherapyPart 16: Discharge of patients23 Advice on the implant l May be also provided to relatives and carers l May be also provided to referring clinician l Information should be carried by the patient at all times

Radiation Protection in RadiotherapyPart 16: Discharge of patients24 Advice to patients l Describe the implant purpose l Advice on precautions: n e.g. after 125-I seed implant in the prostate urinate through a strainer for a couple of days to catch all dislocated sources l Any restrictions for contact: n e.g. go not stay in the vicinity of pregnant women for an extended period of time (best specify the time)

Radiation Protection in RadiotherapyPart 16: Discharge of patients25 Advice to others who may be in contact with the patient l Relatives l Friends l Carers l Referring clinicians

Radiation Protection in RadiotherapyPart 16: Discharge of patients26 Also consider: l What happens if the patient requires emergency treatment? n Surgery? l What happens if the patient dies? n Autopsies? n Cremation?

Radiation Protection in RadiotherapyPart 16: Discharge of patients27 Also consider: l What happens if the patient requires emergency treatment? n Surgery? l What happens if the patient dies? n Autopsies? n Cremation? In practice this depends on many factors - it is best to involve the responsible medical physicist or RSO in the procedure for advice

Radiation Protection in RadiotherapyPart 16: Discharge of patients28 Emergency surgery, autopsies, cremation l Must involve a radiation expert l Therefore it is essential that n the patient can be identified as having a radioactive implant n it is possible for others to contact someone who knows the radiation details of the implant

Radiation Protection in RadiotherapyPart 16: Discharge of patients29 Identification of patient who have a permanent implant l Patient and relatives must know about it l Patient should carry relevant information (implant type, isotope, activity, date of implant, contact details) with him/her at all times: n wristband n card in wallet

Radiation Protection in RadiotherapyPart 16: Discharge of patients30 Summary l It is essential to monitor patients prior to discharge after they had received a temporary brachytherapy implant l There are recommended limit values for the implanted activity above which patients should not be discharged from hospital. l Written discharge rules should be established for patients with permanent implants which include limit values for activities in the patient l Written advice must be provided to patients with permanent implants

Radiation Protection in RadiotherapyPart 16: Discharge of patients31 Where to Get More Information l Parts 6 and 11 l References: NRCP 37

Any questions?

Question: What information would you look for in an information sheet handed out to a patient after a radioactive implant using 198-Au seeds of a half life of 2.7 days?

Radiation Protection in RadiotherapyPart 16: Discharge of patients34 Information required l Description of the implant including isotope, half life and estimated activity l Treating clinician and/or other persons who could provide more details on the implant l Contact in case of emergency l Advice on appropriate precautions: e.g. Do avoid contact with pregnant women and children for … days l Advice on appropriate actions if a source becomes dislodged l A note to make sure other clinicians or health professionals are informed about the nature of the implant if they are in contact with the patient within the next … days