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Respiration and Applied Tension Strategies to Reduce Vasovagal Reactions to Blood Donation

Not Applicable
Conditions
Syncope, Vasovagal
Registration Number
NCT03159156
Lead Sponsor
McGill University
Brief Summary

For a number of years, researchers have examined the effects of the muscle-tensing technique, Applied Tension (AT), on blood donation-related vasovagal symptoms and donor retention. AT was developed originally to reduce symptoms and avoidance behaviour in people with strong fears of blood and needles (phobics). It was based on the idea that exercise-related increases in blood pressure might be able to counteract the effects of stimuli that lead to a decrease in delivery of blood to the brain. AT was adapted for non-phobic blood donors and significant reductions in self-reported vasovagal symptoms and the need for nurse-initiated treatment as well as increases in donor retention were observed in some groups.

That said, individual response to AT is quite variable. This is probably related to recent research indicating that exercise-related maintenance of heart rate and blood pressure plays only a minor role in reducing vasovagal symptoms. Rather, AT appears to be working at least in part by regulating breathing and reducing the possibility of hyperventilation. Pilot results suggest that a novel intervention aimed specifically at breathing may be more effective and reliable than traditional AT. To evaluate this idea, 408 blood donors at mobile clinics in colleges and universities will be assigned randomly to four conditions. In brief, 5-minute preparation sessions using a notebook computer, donors will either learn a respiration control technique to avoid hyperventilation, AT, both, or neither. As a manipulation check and also a means of examining mechanisms of the interventions, e.g., the possibility that AT may work by regulating breathing and CO2, participants will wear non-invasive portable capnometers while they are giving blood. Outcome will also be assessed by self-report of vasovagal symptoms, observational data, and number of return visits to a blood clinic in the following year verified by the provincial blood collection agency, Héma-Québec. As a secondary aim, the research will examine possible moderating effects of pre-donation anxiety and sex.

The development of simple, effective approaches to reduce vasovagal symptoms during blood donation has the potential to improve the blood donation experience and blood donor retention as well as encourage people who have never given blood to consider the procedure. It will also improve medical and dental care more generally given the use of needles in so many procedures.

Detailed Description

See above.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
408
Inclusion Criteria
  • Healthy volunteer blood donors.
Exclusion Criteria

Study & Design

Study Type
INTERVENTIONAL
Study Design
FACTORIAL
Primary Outcome Measures
NameTimeMethod
Change in End Tidal CO2change in mean value during the pre-donation waiting period (registration to going to chair, approximately 30 minutes) to the mean value in the donation chair (approximately 15 minutes)

assessed by ambulatory monitor (capnometer)

Change in Respiration Ratechange in mean value during the pre-donation waiting period (registration to going to chair, approximately 30 minutes) to the mean value in the donation chair (approximately 15 minutes)

assessed by ambulatory monitor (capnometer)

Blood Donation Reactions Inventorycompleted in the recovery area, approximately 15 minutes after blood donation

questionnaire assessing presyncopal vasovagal symptoms

Research Assistant Observationsduring blood donation

participant anxiety, fainting, whether or not treatment for a vasovagal response required, etc., noted by a research assistant

Secondary Outcome Measures
NameTimeMethod
Change in Spielberger State Anxiety Scale Scorecompleted just after registering at the clinic and also in the recovery area, approximately 15 minutes after blood donation, to assess change in anxiety

self-report questionnaire

Medical Fears Surveycompleted in the recovery area, approximately 15 minutes after blood donation

self-report questionnaire

Change in Systolic Blood Pressuremeasured just after registering at the clinic and also in the recovery area, approximately 15 minutes after blood donation, to assess change in blood pressure

in mmHg

Change in Diastolic Blood Pressuremeasured just after registering at the clinic and also in the recovery area, approximately 15 minutes after blood donation, to assess change in blood pressure

in mmHg

Change in Heart Ratemeasured just after registering at the clinic and also in the recovery area, approximately 15 minutes after blood donation, to assess change in heart rate

in bpm

Blood Donor Returnone year after participating in the study

number of times the donor returns to give blood again in a one-year time frame as reported by Hema-Quebec

Trial Locations

Locations (1)

McGill University

🇨🇦

Montréal, Quebec, Canada

McGill University
🇨🇦Montréal, Quebec, Canada
Blaine Ditto, PhD
Contact
514-398-6097
blaine.ditto@mcgill.ca

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