A. The national blood transfusion service in the UK collects around 2.5 million blood donations a year from 1.7 million registered donors. The NHS needs 7,000 voluntary donations of blood daily but only around 4 per cent of the eligible population are active donors. The need for more new and regular donors is, therefore, an ongoing priority. Types of transfusion and examples of their uses are given in Panel 1.
Recent changes in UK donor guidelines discontinued the upper age limit of 65 years for existing donors. Healthy men can now donate up to four times a year (at not less than 12-week intervals) and healthy women up to three times a year (at not less than 16-weekly intervals). A minimum weight of 50kg is required.
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Harm reduction
The procedures surrounding whole blood donation and transfusion are detailed in “Guidelines for the blood transfusion services in the UK (The Red Book)”.¹ Safety and harm reduction are ensured in three ways. The first is by adherence to the evidence-based criteria set out in the guidelines, which give specifications for all materials used and produced by the transfusion service.
The second is the initial completion, at donation sessions, of a comprehensive questionnaire by prospective donors, relating to their health, lifestyle, travel history, past medical and sexual history and any concurrent medication. Capillary blood is also tested to ensure that male and female donors have minimum haemoglobin values (135 and 125g/L, respectively) and all donors are asked to report any illness that develops within 14 days of donation.
The third safety measure is post-donation laboratory testing for blood groups, syphilis and blood borne viruses (including HIV, hepatitis B and C and human T lymphotropic virus). Additional tests may be undertaken in individual cases for malaria, Trypanosoma cruzi, West Nile virus and cytomegalovirus. Although this expensive and laborious undertaking is a big step forward in recipient safety, a problem still exists with newly acquired infections where neither symptoms nor seropositivity have emerged. The questionnaire described above should address this issue.
Problem drugs
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Detailed knowledge among front-line health care workers of how medication may affect blood donation is sparse and there is little guidance in popular therapeutic publications. For example, only three examples appear in the 2012 Electronic Medicines Compendium³ and the current BNF: the oral retinoids acitretin, alitretinoin and isotretinoin. This may seem extraordinary when so many summaries of product characteristics list potentially toxic and life-threatening effects.
Pregnant women are a key group for blood transfusions, and teratogenicity is a possibility if blood containing retinoids were to be given to these recipients. Donation is not allowed if a person has ever taken etretinate (Tigason — no longer in use) or has taken acitretin (Neotigason) in the past 24 months or alitretinoin (Toctino) or isotretinoin (Roaccutane) in the past four weeks. (There are no published data that topical retinoids cause birth defects.) For the same reason, patients taking carbimazole or propylthiouracil may not donate blood. If treatment is stopped, 24 months must elapse before a donation.
Patients taking antiandrogens are also not permitted to donate. Blood containing finasteride or dutasteride can cause abnormal development of the genitalia of male fetuses if given to pregnant women. A donation must not be made if finasteride has been taken in the past four weeks or dutasteride in the past six months.
Blood from donors currently taking non-steroidal anti-inflammatory drugs or antiplatelet medicines cannot be used for preparing platelet packs (see Panel 1) because of their platelet inhibitory effects. Aspirin and piroxicam require a five-day interval between use and donation and other NSAIDs require 48 hours. These agents do not affect donations for red blood cell transfusions, although donations may be refused if the medication is for a serious long-term condition.
Any individual who has ever injected illicit drugs (including anabolic steroids) may not donate because of the long latent period before some blood-borne viruses, such as HIV, can be detected.
Medicines as indicators
General opinion is that, in most cases, plasma concentrations of drugs in donated blood are not sufficiently high to cause harm to recipients. Normally of greater concern is any underlying illness in patients and, of course, medicines are a useful indication of this. Illness can make giving blood a risk to the donor as well as posing a risk for recipients. For example, if a patient is taking a proton pump inhibitor, he or she may have a peptic ulcer, and this would rule out donation (see Panel 2). And if a patient is using asthma inhalers or products for eczema, caution is also required. These and further examples of conditions that pose potential risks are explained further in Panel 2.
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An important prerequisite for blood donation is that the donor should be fit and well on the day of donation and that any medical condition should be under control. Blood from a donor with an infection can be dangerous for the recipient. As a precaution, at least seven days must have passed since any systemic antibiotic, antifungal or antiviral therapy before a donation can be made. Similarly, dental patients must wait for at least seven days after tooth extraction, root canal treatment, dental capping or implantation before giving blood because of the risk of bacteraemia. (Fillings or a scale and polish only require a 24-hour wait.)
Caution is also required with donors taking drugs that may mask the signs of infection and inflammation (eg, glucocorticoids, immunosuppressants and some antibiotics). A donation will be permitted if a course of oral or injected steroids has been completed more than seven days ago. Donations should not be taken for at least 12 months after treatment with methotrexate, ciclosporin or phototherapy has finished.
This patient
The answer to this patient’s question would depend on what medicines he is taking and why. As long as he is not taking any of the problem medicines discussed and his medical condition is acceptable, his donation will not be refused.
It may be worth checking if he is currently undergoing any medical investigations, and if he has been referred for a specialist opinion or is on a hospital waiting list, because donation may need to be deferred unless the condition or suspected condition would not be a contraindication to donation.
Donors taking part in clinical trials of drugs cannot be accepted until their involvement in the trial has finished, or the designated clinical support team member has examined the trial protocol and agreed that donors participating in that trial can be accepted. This ruling applies to healthy volunteers (as in phase I clinical trials) as well as patients.
Further reading
The “Whole blood and component donor selection guidelines” is a 196-page document that gives valuable, detailed and comprehensive information on personal, medical and pharmacological criteria determining donor eligibility. The index contains around 970 entries for medical conditions and 290 for drugs. Immunisations are also covered. It should allow healthcare professionals to give advice in most circumstances.
References
- Guidelines for the Blood Transfusion Services in the UK (7th edition, October 2005). http://www.transfusionguidelines.org.uk/
- Statutory Instrument 2005 No. 50. The Blood Safety and Quality Regulations 2005. ISBN 0 11 051622 2 available at http://www.legislation.gov.uk/
- Electronic Medicines Compendium, 2012 (Datapharm). http://www.medicines.org.uk/
- The Whole Blood and Component Donor Selection Guidelines, Edition 203; Release 16, February, 2013. http://www.transfusionguidelines.org.uk/docs/pdfs/dsg_wb_203_16_01.pdf
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This post was last modified on December 8, 2024 3:14 am