Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT03298880 |
| Other study ID # |
1617/043 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
November 1, 2017 |
| Est. completion date |
February 5, 2018 |
Study information
| Verified date |
June 2021 |
| Source |
University of Exeter |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
A prototype for a Valsalva Assist Device (VAD), which provides resistance to exhalation, has
been developed and is ready for testing in healthy volunteers. There is a need to ensure the
device can deliver the required strain and evaluate the physiological response (lowered heart
rate) when used to deliver a Valsalva manoeuvre (VM) with and without postural modification.
Description:
The aim of this study is to evaluate the performance of a novel Valsalva assist device (VAD)
in healthy volunteer and to confirm the physiological effects of a modified VM.
Specific Objectives:
To measure and compare peak strain pressure and duration produced using the device compared
to a standard manometer in supine and modified postures
To evaluate whether there is a difference in vagal tone (drop in heart rate) in healthy
volunteers performing a VM using the VAD versus manometer.
To evaluate whether there is a difference in vagal tone (drop in heart rate) in healthy
volunteers performing a modified VM versus a standard supine VM using the VAD.
To evaluate whether there is a difference in vagal tone (drop in heart rate) in healthy
volunteers performing a modified VM versus a standard supine VM using a manometer.
The investigators will conduct a single centre repeated measures observational study of use
of the device to generate a Valsalva strain in a sample of healthy adult volunteers from the
University of Exeter or RD&E Hospital staff. All participants will be screened for
eligibility and undergo informed written consent prior to participation. If participants fail
screening due to abnormal clinical readings or vital signs, the chief investigator will
review them, any urgent abnormalities (very unlikely) would be reviewed by the chief
investigator or delegated emergency department doctor as soon as they are discovered.
Depending on the severity, if treatment is required urgently then they will be treated in the
emergency department. Otherwise, they will be referred back to their GP. Potential
participants will be given written information about the study at least 24 hours prior to
recruitment and interested individuals invited to attend screening, recruitment and testing.
Potential participants will be invited to express an interest in taking part by responding to
the trial poster. These posters will be displayed in the medical student common rooms ED
department notice board. The potential participant contacts the researcher leading the
practical aspects of the trial by phone or email. Respondents will be asked how they would
like to receive further information (post, email, and phone) and offered an appointment at
the Clinical Research Facility (CRF) for screening and written consent if eligible, at their
convenience but at least 24 hours after receiving the information sheet. Given the simple,
safe and quick nature of the interventions, participants will be given the choice to take
part after written consent or to return on another date, whichever they would prefer, to
ensure minimal visits whilst giving participants further time to consider taking part should
they wish.
The VM is an extremely safe, physiological manoeuvre which is used in everyday life (eg
straining at stool) and has been used in trial conditions and clinical practice many
thousands of times with no serious adverse events. The investigators will exclude
participants who could conceivably be at any risk of harm from performing a VM or from the
use of the device.
The screening will include 12 lead ECG and physical examination including observations of
heart rate, oxygen saturations, respiratory rate and blood pressure. Any participants with
any detected abnormalities, whether they are excluded from participation or not, will be
informed and referred to their primary care physician as appropriate. All testing will be
conducted in the clinical research facility (CRF) of the Royal Devon & Exeter Hospital,
according to a strict trial protocol.
Test Valsalva Manoeuvres:
Participants will undergo a total of 4 VMs of the following 4 variations in random order,
stratified by method of strain generation to ensure balance between the order of manometer
and device use:
1. Supine VM using a manometer. Supine Valsalva strain using a manometer visible to the
participant with a target of 40mmHg for 15 seconds
2. Supine VM using the device. Supine Valsalva strain using the device connected to
manometer invisible to the participant but visible to a researcher for 15 seconds
3. Modified VM using a manometer. Semi-recumbent (at 45 degrees) Valsalva stain using a
manometer visible to the participant with a target of 40mmHg for 15 seconds followed by
supine positioning and passive 45-degree leg lift immediately at the end of the strain
for a further 15 seconds (the modified VM)
4. Modified VM using the device. Semi-recumbent (at 45 degrees) Valsalva strain using the
device connected to manometer invisible to the participant but visible to a researcher
for 15 seconds followed by supine positioning and passive 45-degree leg lift immediately
at the end of the strain for a further 15 seconds (the modified VM)
