Summary of medicine characteristics - KRYPTOSCAN GENERATOR
KryptoScanTM generator
2 QUALITATIVE AND QUANTITATIVE COMPOSITION
Rubidium (81Rb) bound as ion to a cation exchange resin which is in equilibrium with the daughter-product Krypton (81m Kr )and serves as a generator for Krypton (81mKr) gas.
The generator is available with activities ranging between 75–740 MBq
Physical characteristics
Rubidium (81Rb) decays with a physical half-life of 4.58 hours to its metastable daughter-product Krypton (81mKr) thus generating this short-lived radionuclide with a half-life of 13 seconds. Krypton (81mKr) decays by isometric transition to Krypton (81Kr), emitting pure gamma radiation of 0.190 MeV which is internally converted. 81Kr decays to stable 81Br with a halflife of T/2 = 2.1 × 105 years.
Radionuclide generator.
4.1 Therapeutic indications
Investigation of pulmonary ventilation, according to the low radiation dose, this product can be especially recommended for paediatric examination.
Combined with a pulmonary perfusion scintigraphy for diagnosis of pulmonary embolism.
Pulmonary ventilation (81mKr) / perfusion (99Tc-macroaggregation) studies are possible because of the different spectrometric windows of 81mKr and 99mTc.
4.2 Posology and method of administration
Krypton images are acquired during the continuous inhalation of the short lived and otherwise inert radioactive gas, Krypton (81mKr). This is eluted with humidified air from a rubidium generator and administered to the patient through a face mask or airway.
In general adequate imaging is achieved when 200.000–350.000 counts are accumulated per gamma camera image. This corresponds to approx. 18 MBq/kg body weight. Most investigation requires a number of views = 4 to 6.
The activities for children may be calculated according to the following equation:
Activity-child (MBq) = Activity-adult (MBq) x body weight (kg)
70 (kg)
Continuous inhalation is stopped upon acquisition of approx. 300.000 counts per
gamma camera image.
4.3 Contraindications
None known.
4.4 Special warnings and precautions for use
Radiopharmaceuticals may be used and administered only by authorised persons.
Radiopharmaceuticals intended for administration to patients should be prepared by the user in a manner which satisfies both radiological safety and pharmaceutical quality requirements.
4.5 Interaction with other medicinal products and other forms of interaction
Diazepam in sedative doses and general anaesthetic agents may affect the distribution of radioactive gases in the lung by slightly shifting the activity to the lung apex and reducing basal accumulation.
4.6 Fertility, Pregnancy and lactation
When it is necessary to administer radioactive medicinal product to women of childbearing potential, information should always be sought about pregnancy. Any woman who has missed a period should be assumed to be pregnant until proven otherwise. Where uncertainty exists it is important that radiation exposure should be the minimum consistent with achieving the desired clinical information. Alternative techniques which do not involve ionising radiation should be considered.
Radionuclide procedures carried out on pregnant women also involve radiation doses to the foetus. Only imperative investigations should be carried out during pregnancy, when the likely benefit exceeds the risk incurred by mother and foetus.
Before administering a radioactive medicinal product to a mother who is breastfeeding consideration should be given as to whether the investigation could reasonably delayed until the mother has ceased breast-feeding and as to whether the most appropriate choice of radiopharmaceutical has been made, bearing in mind the secretory activity in breast milk. If administration of Krypton (81mKr) gas is considered necessary, however, breast-feeding need not be specifically interrupted
4.7 Effects on ability to drive and use machines
Effects on the ability to drive or to operate machines have not been described.
4.8 Undesirable effects
For each patient, exposure to ionising radiation must be justifiable on the basis of likely clinical benefit. The activity administered must be such that the resulting radiation dose is as low as reasonably achievable bearing in mind the need to obtain the intended diagnostic or therapeutic result.
Exposure to ionising radiation is linked with cancer induction and a potential for development of hereditary defects. For diagnostic nuclear medicine investigations the current evidence suggests that these adverse effects will occur with negligible frequency because of the low radiation dose incurred.
For more diagnostic investigations using a nuclear medicine procedure the radiation dose delivered (EDE) is less than 20 mSv. Higher doses may be justified in some clinical circumstances.
No adverse/undesirable effects have been reported for this agent.
4.9 Overdose
4.9 OverdoseAlso, in the unusual event of radiation overdose caused by an unrequired but prolonged period of krypton gas inhalation, due to the rapid washout from the lungs during normal ventilation, patients need only be removed from the source of radiation to a fresh and uncontaminated atmosphere.
5 PHARMACOLOGICAL PROPERTIES
5.1 Pharmacodynamic properties
ATC-Code: V09E X (Other respiratory system diagnostic radiopharmaceuticals)
Krypton is an inert gas which is not metabolized and in the concentrations applied Krypton (81mKr) shows no pharmacodynamic effects.
5.2 Pharmacokinetic properties
Krypton (81mKr) is an inert gas with a short biological half-life. Due to its rapid decay the effective half-time of lung elimination is equal to the physical half-life of 13 seconds. Peripheral Krypton (81mKr)-activity is exhaled after the first passage.
5.3 Preclinical safety data
5.3 Preclinical safety dataNo data available.
6 PHARMACEUTICAL PARTICULARS
6.1 List of excipients
PTFE (polytetrafluoroethylene) membrane with immobilized poly(styrenedivinylbenzene) cation exchange resin with sulphonic acid functional groups.
6.2 Incompatibilities
None known.
6.3 Shelf life
The shelf life of the product is 20 hours after activity reference date. The expiry date is stated on the generator label.
6.4 Special precautions for storage
Do not store the generator at temperatures above 25°C. Use a lead shielding. Storage should be in accordance with the national regulations for radioactive materials.
6.5 Nature and contents of container
The radionuclide generator contains the mother-radionuclide 81Rb immobilized on a membrane. The daughter-radionuclide 81mKr is eluted by passing environmental air over the membrane. The produced gas from the generator contains therefore the radionuclide 81mKr mixed with environmental air.
The generator containing 81mKr is placed in a lexan housing and then in a shielding. The shielding is fixed within a synthetic housing.
6.6 Special precautions for disposal
6.6 Special precautions for disposalWaste must be disposed of in accordance with National Regulations for radioactive material.
7 MARKETING AUTHORISATION HOLDER
Mallinckrodt Medical B.V.
Westerduinweg 3
1755 LE Petten
Netherlands
8 MARKETING AUTHORISATION NUMBER(S)
PL 12288/0006