Vasovagal reactions in blood donors: risks, prevention and management

Abstract

This narrative review examines current research on risk factors, prevention methods and management strategies for vasovagal reactions (VVRs) that occur during or as a result of blood donation. VVRs are important to blood collection agencies (BCAs) as they negatively impact the number of completed collections, perceptions of the safety of blood donation and rates of donor return. There has been significant progress in understanding and preventing VVRs in blood donation in recent years, with a multitude of risk factors identified. This has resulted in many BCAs implementing evidence-based strategies, such as donor age and weight restrictions. However, the profile of our most vulnerable donors and features of the donation setting that may protect these donors from experiencing a VVR have not been identified. Furthermore, an increased number of trials of physiological and psychological prevention interventions to reduce both immediate and delayed VVRs have been reported. However, a lack of methodological consistency in operationalising interventions to reduce or prevent VVRs means that the identification of effective VVR prevention strategies remains a challenge for practitioners. Furthermore, research is still required to determine how to successfully implement prevention and management strategies into standard operating procedures within collection centres. Finally, research in the management and mitigation of the effect of VVRs is currently only suggestive of what should be done to care for the donor who reacts and how to empower those donors to return. Collectively, research into these aspects of VVRs will provide support to donors and BCAs and improve the safety of blood donation.

Predonation fears identify young donors at risk for vasovagal reactions

“…An ancillary contribution of this study is some novel information on the relationship between sleep and risk of vasovagal reactions. Blood donors are typically advised to get a good night's sleep before their donation, and adequate sleep has been cited as an important factor in the prevention of vasovagal reactions, yet the empirical evidence in support of this advice is surprisingly limited. Takanashi and colleagues identified donor‐reported sleep duration in the previous night as a significant predictor of vasovagal reactions among whole blood and apheresis donors, with reports of less than 6, 6 to 6.9, and 7 to 7.9 hours all being at higher risk than those who reported at least 8 hours of sleep.…”

2018 European Conference on Donor Health and Management

“…Finally, Prof. Barbara Masser (Brisbane, Australia) has published widely on the problems of retaining first time donors (Bagot et al, ), on vaso‐vagal reactions (Thijsen & Masser, ) and the theoretical underpinnings of donor behaviour (Williams et al, ). Here, she spoke about the time course of emotion in donors on the pathway through donation.…”

The Effect of Telephone and Message Reminder on Donor Gain in Temporary Blood Deferrrals: Randomised Controlled Trial

“…4 Bağış öncesi sıklıkla görülen baygınlık, baş dönmesi, sersemlikle kendini gösteren vasovagal reaksiyonlar sürecin olumsuz değerlendirilmesine neden olabilir. 18,19 Donasyon öncesi nabzın 90/dk ve üzerinde olması, diastolik kan basıncının 70 mm/Hg ve altında olması, 6 saat ve daha az uyuma, yemekten 4 saat ve daha uzun süre geçmiş olması, vasovagal reaksiyonlarda öngörülebilir özelliklerdendir. 18 Dolayısıyla uygun bilgilendirme, kan bağışından önce 500 ml su ya da izotonik sıvı tüketimi, kas germe egzersizi şeklinde yapılacak uygulamalarla olumsuz deneyimlerin azaltılması yanında, taşikardi, baş dönmesi, gerekçe belirtmeksizin bağıştan vazgeçme gibi nedenlerle olan retlerin önüne geçilebilir.…”

“…18,19 Donasyon öncesi nabzın 90/dk ve üzerinde olması, diastolik kan basıncının 70 mm/Hg ve altında olması, 6 saat ve daha az uyuma, yemekten 4 saat ve daha uzun süre geçmiş olması, vasovagal reaksiyonlarda öngörülebilir özelliklerdendir. 18 Dolayısıyla uygun bilgilendirme, kan bağışından önce 500 ml su ya da izotonik sıvı tüketimi, kas germe egzersizi şeklinde yapılacak uygulamalarla olumsuz deneyimlerin azaltılması yanında, taşikardi, baş dönmesi, gerekçe belirtmeksizin bağıştan vazgeçme gibi nedenlerle olan retlerin önüne geçilebilir. 19 Planlı bağış yapılacaksa kan bağışı ünitesinden bireylere randevu verilmesi ve donasyondan önce yapılması gerekenlere ilişkin "tam dinlenik halde bulunma", "2 saat öncesine kadar tam bir öğünle beslenmiş olma" gibi basit önerilerde bulunulması uykusuzluk/yorgunluk, açlık gibi nedenlerle olan retleri azaltabilir.…”