describes measures , which , if followed , support the continued integrity of the vials prepared throughout the period of use . It also covers steps which should be taken to ensure that the administration is done correctly . This is important . Although the products the guidance relates to are all for diagnostic use and therefore are not in themselves harmful from a therapeutic point of view , if administered incorrectly they can lead to misdiagnosis , delays in diagnosis and unnecessary radiation exposure .
What are the current issues of using multidose vials ? Ideally parenteral products should be for single use . 2 This is the ideal , because they can be discarded after the dose has been drawn up and there is much less risk of contamination of the vial . Some radiopharmaceuticals are presented as single-use vials . These tend to be newer products , where the patient numbers are low or where the amount of ligand is particularly important – say , for example , in the case of radiolabelled antibodies such as LeukoScan ( a radiopharmaceutical used for imaging infection ).
Why then , are so many diagnostic radiopharmaceuticals presented as multidose vials ? The answer , although to some extent historical , lies in their radioactive nature . A certain amount of overage is required if making up a vial of product for a single patient . Each time a vial is made , the generator elution vial has to be handled . This accounts for a significant proportion of the operator ’ s radiation exposure . The more vials made , the more times the elution vial has to be handled . If more overage has to be allowed overall , the total amount of radioactivity used from the vial will also be higher .
Both these factors result in a Health and Safety risk to the operator making the products , which is reduced as follows through the use of multidose vials :
• Less total activity is handled as a result because there is less wastage
• The generator elution vial is handled less .
And unlike single-use products , vials licensed for multiple use contain preservatives , which reduce the risk of any contamination replicating , should it occur .
What are the risk factors associated with individual injectable medicines , their preparation and administration ? There are a number of risks that must be considered .
Radiation risk to operators First of all , I would like to make it clear that if handled correctly , the radiation risks to patients and staff are extremely low . It is important to remember that there are risks in everything we do , and the extremely low risk of harm to patients as a result of their radiation exposure is very carefully assessed and offset against the overall benefit of their having the test in question .
Operator radiation doses are measured and assessed routinely in the Radiopharmacy – both the dose received to the entire body , as well as that received to the fingers . Most operators making up technetium-99m radiopharmaceuticals will have a low whole body dose . To put this in perspective , a typical dose may be in the region of 4mSv a year , compared with the average dose received in the UK of 2.7mSv , and a resident of Cornwall of just under 8mSv . 3
However , nothing is totally devoid of risk , and the higher the radiation exposure to the radiopharmacy operator or patient , the higher the risk . Therefore keeping the exposure levels low for both groups is vital . The Safe Drawing Up document , therefore , incorporates radiation safety recommendations as well as advice for minimising risk of repeated radiation exposure , for example .
Risk of microbial contamination of the product If manipulations are carried out at ward or clinic level and injections are not administered immediately , there is an increased risk of microbial contamination that can lead to
18 HHE 2018 | hospitalhealthcare . com