Evaluation of interventions to prevent vasovagal reactions among whole blood donors: rationale and design of a large cluster randomised trial.

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Walker, Matthew 
Mehenny, Susan 
Gilchrist, Philippe T 

BACKGROUND: Vasovagal reactions (VVRs) are the most common acute complications of blood donation. Responsible for substantial morbidity, they also reduce the likelihood of repeated donations and are disruptive and costly for blood services. Although blood establishments worldwide have adopted different strategies to prevent VVRs (including water loading and applied muscle tension [AMT]), robust evidence is limited. The Strategies to Improve Donor Experiences (STRIDES) trial aims to reliably assess the impact of four different interventions to prevent VVRs among blood donors. METHODS: STRIDES is a cluster-randomised cross-over/stepped-wedge factorial trial of four interventions to reduce VVRs involving about 1.4 million whole blood donors enrolled from all 73 blood donation sites (mobile teams and donor centres) of National Health Service Blood and Transplant (NHSBT) in England. Each site ("cluster") has been randomly allocated to receive one or more interventions during a 36-month period, using principles of cross-over, stepped-wedge and factorial trial design to assign the sequence of interventions. Each of the four interventions is compared to NHSBT's current practices: (i) 500-ml isotonic drink before donation (vs current 500-ml plain water); (ii) 3-min rest on donation chair after donation (vs current 2 min); (iii) new modified AMT (vs current practice of AMT); and (iv) psychosocial intervention using preparatory materials (vs current practice of nothing). The primary outcome is the number of in-session VVRs with loss of consciousness (i.e. episodes involving loss of consciousness of any duration, with or without additional complications). Secondary outcomes include all in-session VVRs (i.e. with and without loss of consciousness), all delayed VVRs (i.e. those occurring after leaving the venue) and any in-session non-VVR adverse events or reactions. DISCUSSION: The STRIDES trial should yield novel information about interventions, singly and in combination, for the prevention of VVRs, with the aim of generating policy-shaping evidence to help inform blood services to improve donor health, donor experience, and service efficiency. TRIAL REGISTRATION: ISRCTN: 10412338. Registration date: October 24, 2019.


Acknowledgements: This work was supported by Health Data Research UK, which is funded by the UK Medical Research Council, Engineering and Physical Sciences Research Council, Economic and Social Research Council, Department of Health and Social Care (England), Chief Scientist Office of the Scottish Government Health and Social Care Directorates, Health and Social Care Research and Development Division (Welsh Government), Public Health Agency (Northern Ireland), British Heart Foundation and Wellcome. Independent Chair and Clinical Trialist (Prof Jane Armitage); Funders (Dr Gail Miflin, Jane Green, Mike Stredder, Prof David Roberts, Dr Farrah Shah); Chief and Principal Investigators (Prof Emanuele Di Angelantonio, Prof John Danesh); Sponsor Representative (Dr Nick Watkins and Oluwayomi Adegbaju) Scientific Coordinator (Dr Amy McMahon); NHSBT Consultant Haemotologist (Prof Mike Murphy) NBR Laboratory Coordinator (Dr Jennifer Sambrook, Dr Kathy Stirrups); Senior Statisticians (Dr Angela Wood, Dr Stephen Kaptoge); Chief Information Officer (Dr Matthew Walker); NHSBT Project Lead (Susan Mehenny), Project Administration/coordination (Susan Burton, Shannon Duthie, Elisha Johnson); NIHR BioResource Representative (Dr Nathalie Kingston), Independent Member (Prof Beverley Hunt,) and Lay Members (Ms Elizabeth Morse and Ms Roxanne Stirling). Study Management Committee Principal and co-Investigators (Prof Emanuele Di Angelantonio, Prof John Danesh, Prof David Roberts and Dr Philippe Gilchrist); Scientific Coordinator ( Dr Amy McMahon); Sponsor Representative (Dr Nick Watkins and Oluwayomi Adegbaju), NBR Representative (Dr Nathalie Kingston), NBR Laboratory Coordinator (Dr Jennifer Sambrook, Dr Kathy Stirrups); Chief Information Officer (Dr Matthew Walker); NBR Informatics Director (Dr Neil Walker) Senior Statisticians (Dr Stephen Kaptoge, Dr Angela Wood, Dr Michael Sweeting); NHSBT Project Lead (Susan Mehenny); Senior Research Sister North (Rosemary Godfrey); Senior Research sister South (Louise Allen); Project Administration NHSBT (Joanne Addy, Louise Stennett); Project Administration/coordination, University of Cambridge (Elisha Johnson, Shannon Duthie, Susan Burton, Susan Irvine); NHSBT Consultant (Naim Akhtar); Lay Members (Paul Harvey, Elizabeth Allen and Michael Berkson) NHSBT donation team managers (team name) Katherine Willdridge (Ashford), Matt Byron (Bath), Anna Turco (Beckenham Team), Richard Brain (Birmingham Donor Centre), Ruth Turner and Laura Wood (Bradford Donor Centre), Clare Carman (Brighton), Charlotte Hughes and Rachel Newman (Bristol), Alison Dent / Claudia Hana (Bristol Donor Centre), Kennesha McIntosh (Cambridge), Alan Wakeman (Cambridge Donor Centre), Ana Corexo (City), Mandy Wright (Cornwall), Fiona Price (Coventry), Sharon Donald (Cumbria), Louise Easton (Dorchester), Nicole Ciulea (Edgware Donor Centre), Vanessa Hunt/Lydia Bullard (Essex Team), Michaela Clarke (Exeter), Ruth Aston (Gloucester Donor Centre), Natalie Peters (Herts), Anna Turco (Hither Green), Clare Carman (Horsham), Susan Baker (Hull), Karen Wright (Huntingdon), Danielle Redden (Ipswich), Barbara Manhambara (Lancaster), Rachel Adams / Georgina Belvins (Lancaster Donor Centre), Marc Hudson (Leeds), Lynne Ainsworth (Leeds City Donor Centre), Adele Mayer (Leicester), Karen Ellis (Leicester Donor Centre), Victoria East (Lincoln), Sharon Jones (Liverpool), Theresa Robinson (Liverpool Donor Centre), Claire Anthony (London Middlesex), Emma Martin (Luton Donor Centre), Grace De Lira (Maidstone), Sue Platt / Karen Ackerley (Manchester), Lindsay Williams (Manchester Norfolk House), Karen Ackerley & Jo Holbrook (Manchester Plymouth Grove), Christina Hackney (Milton Keynes), John Townsend (Newcastle), Lynn Woods and Maria Dineen (Newcastle Donor Centre), Kate Fulton (Northampton), Ruth Patterson (Northwich), Amanda Rock (Norwich), Lorraine Pick (Nottingham), Jenny Wright (Nottingham Donor Centre), Kakale Sebogiso (Oxford Donor Centre), Caroline Morrice (Plymouth Donor Centre), Vicky Roberts (Poole Donor Centre), Judy McCabe (Portsmouth), Penny Crook-Jones (Reading), Jane Dawson (Sheffield Donor Centre), Catherine Fretwell (Sheffield North), Jill Rowlands / Penny Swift (Sheffield South), Sam Clark (Slough), Simone De-leon (Solihull ), Claire Alexander (Southampton Donor Centre), Annie Butterworth & Dona Blofield (Southampton Team), Diane Furnival (Stoke Donor Centre), Chanelle Henry (Surrey), Adele Lapworth / Clare Bloomfield (Sutton Coldfield), Penny Crook-Jones (Swindon), Sally Bleeks (Taunton), Jennifer O’Brien & Alison Thomson (Teesside), Patsy Lowson (Thetford), Christine St Romaine (Tooting Donor Centre), Karl Grover (Tunbridge Wells), Carolyn Roost / Sasa Cromack (WEDC), Rebecca Guest (Worcester), Tracy Bell (York) NHSBT STRIDES Study Administration Team Joanne Addy, Patricia Barrass, Louise Stennett. University of Cambridge STRIDES Helpdesk Shannon Duthie, Elisha Johnson. Previous members: Susan Irvine, Rachel Henry, Susan Burton, Mercedesz Juhasz. Data Management Team Matthew R Walker, University of Cambridge; Charlotte Van Coeverden, University of Cambridge; Michael Daynes, NHSBT, Stuart Halson, NHSBT Study Statisticians Stephen Kaptoge, University of Cambridge; Michael Sweeting PhD, University of Leicester, Angela Wood, University of Cambridge, Ryan Chung, University of Cambridge.

Blood donation, Blood donors, Cluster randomised trial, Cross-over, Factorial design, Stepped-wedge, Vasovagal reactions, Humans, Blood Donors, State Medicine, Syncope, Vasovagal, Water, Blood Donation
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Springer Science and Business Media LLC
NHS Blood and Transplant (NHSBT) (17-01-GEN)
Department of Health (via National Institute for Health Research (NIHR)) (NIHR203337)
British Heart Foundation (RG/18/13/33946)
National Institute for Health and Care Research (IS-BRC-1215-20014)
British Heart Foundation (None)
British Heart Foundation (CH/12/2/29428)
British Heart Foundation (FS/18/56/34177)