Syncope, Vasovagal
Conditions
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.
Interventions
BEHAVIORALApplied Tension
Described above.
BEHAVIORALRespiration Control
Described above.
BEHAVIORALApplied Tension/Respiration Control
Described above.
Sponsors
Canadian Institutes of Health Research (CIHR)
McGill University
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Masking description
Behavioral procedures that cannot be masked to participant or others.
Intervention model description
The primary goal is to examine the role of hyperventilation in blood donation-related vasovagal reactions and whether breathing is influenced by two treatments (alone and in combination) for reactions. The study will examine the clinical impact of these treatments but this is not the primary goal of the project.
Eligibility
Sex/Gender
ALL
Age
18 Years to 39 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy volunteer blood donors.
Exclusion criteria
\-
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in End Tidal CO2 | change 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 Rate | change 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 Inventory | completed in the recovery area, approximately 15 minutes after blood donation | questionnaire assessing presyncopal vasovagal symptoms |
| Research Assistant Observations | during blood donation | participant anxiety, fainting, whether or not treatment for a vasovagal response required, etc., noted by a research assistant |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Heart Rate | measured 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 |
| Change in Spielberger State Anxiety Scale Score | completed 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 |
| Blood Donor Return | one 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 |
| Medical Fears Survey | completed in the recovery area, approximately 15 minutes after blood donation | self-report questionnaire |
| Change in Systolic Blood Pressure | measured 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 Pressure | measured 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 |
Countries
Canada
Contacts
Primary ContactBlaine Ditto, PhD
Outcome results
None listed