Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
The study will evaluate the effect of intermittent negative pressure (INP) on peripheral arterial disease (PAD) patient vascular function and blood flow. Patients will be given either -40mmHg INP or -10mmHg INP which will act as a placebo. Healthy volunteers will be given -40mmHg INP to evaluate changes in vascular function and blood flow with INP in healthy physiology.
Atherosclerosis occurs when blood supply to the lower limbs is restricted upon accumulation of fat in the arteries. Atheroslerosis in the lower limbs is termed peripheral arterial disease (PAD). The initial symptom is pain in the lower limbs followed by ulceration and gangrene. The literature has indicated that intermittent negative pressure (INP) can be used to reduce pain and facilitate wound healing. INP is a non-invasive technique that aims to increase arterial and skin blood flow in lower limbs and foot. This study aims to investigate the underlying mechanisms that are involved in changes in blood flow following application of INP. The Flow-Ox 'boot' will be used to apply INP for periods ranging from 4-8 weeks, for an hour twice per day, to the lower limb to determine the effects of INP on vascular function and blood flow. Specifically, vascular tests such as assessments of endothelial function, arterial stiffness, ankle-brachial pressure index (ABPI) and blood borne metabolic and inflammatory markers will be performed before and after INP application. A pain chart will be employed before and after INP application to determine whether there is any change in perception of pain felt by individuals who suffer from pain associated with lower limb arterial disease.
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Active PAD group | Experimental | -40mmHg of Intermittent Negative Pressure (INP) for 4-8 weeks. |
|
| Placebo PAD group | Experimental | -10mmHg of Intermittent Negative Pressure (INP) for 4-8 weeks. |
|
| Healthy Volunteers | Experimental | -40 mmHg of Intermittent Negative Pressure (INP) for 5 days |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Active Intermittent Negative Pressure (INP) | Device | Application of -40mmHg negative pressure on the lower limb |
|
| Measure | Description | Time Frame |
|---|---|---|
| Change in microvascular blood flow | Microvascular blood flow measurement in foot using laser Dopper imaging. | Baseline, 1 day and 4-8 weeks |
| Change in microvascular endothelial function | Peak blood perfusion response to acetylcholine (ACh) delivered by iontophoresis will be measured using a laser Doppler imager. | Baseline, 1 day and 4-8 weeks |
| Change in arterial stiffness | Brachial pulse wave analysis (PWA) augmentation index (Ax) and carotid-femoral pulse wave velocity (m/s) (PWV) as an indication of arterial stiffness. | Baseline, 1 day and 4-8 weeks |
| Change in macrovascular endothelial function | Brachial endothelial function measured as change in brachial blood vessel diameter (%) upon shear stress. | Baseline, 1 day and 4-8 weeks |
| Measure | Description | Time Frame |
|---|---|---|
| Change in pain score | Self-scoring of pain felt by patient on a visual analogue scale with 0 being no pain at all to 10 being the worst pain ever felt. | Baseline, 1 day and 4-8 weeks |
| Change in concentration of blood borne inflammatory and oxidative stress biomarkers |
Not provided
Inclusion Criteria
PAD Patients:
Healthy Volunteers:
Exclusion criteria
PAD Patients:
Healthy Volunteers:
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Jody McIntosh | PhD student | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| School of Medicine, University of Dundee, Ninewells Hospital & Medical School | Dundee | United Kingdom |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Type | Includes Protocol | Includes SAP | Includes ICF | Document Label | Document Date | Document Uploaded Date | Document File Name |
|---|---|---|---|---|---|---|---|
| Prot_SAP | Yes | Yes | No | Study Protocol and Statistical Analysis Plan | Mar 13, 2019 | May 21, 2019 | Prot_SAP_001.pdf |
Not provided
| ID | Term |
|---|---|
| D058729 | Peripheral Arterial Disease |
| ID | Term |
|---|---|
| D050197 | Atherosclerosis |
| D001161 | Arteriosclerosis |
| D001157 | Arterial Occlusive Diseases |
| D014652 | Vascular Diseases |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Placebo Intermittent Negative Pressure (INP) | Device | Application of -10mmHg negative pressure on the lower limb |
|
Concentration of inflammatory and oxidative stress markers of endothelial activation/damage (including IL-1a, IL-6, IL-10, TNF-a, CRP, E-selectin and sICAM-1) measured in serum and plasma collected from patient blood samples. |
| Baseline, 1 day and 4-8 weeks |
| Change in Ankle-Brachial Pressure Index (ABPI) | Brachial systolic pressure and ankle (dorsalis pedis) systolic pressure (mmHg) measured using Doppler probe. ABPI calculated as ankle systolic pressure divided by brachial systolic pressure. ABPI <0.9 = PAD, ABPI =>1.0 Normal. | Baseline, 1 day and 4-8 weeks |
| D002318 |
| Cardiovascular Diseases |
| D016491 | Peripheral Vascular Diseases |