Evaluating A Non-Invasive Tissue Perfusion Monitor

A Feasibility Study Evaluating A Non-Invasive Tissue Perfusion Monitor Utilising Diffuse Speckle Contrast Analysis

The Pedra perfusion system will be used to assess changes in perfusion in response to physiological stimuli. It will be compared to other standard diagnostics.

Study Overview

• Status: Unknown
• Conditions: Circulatory; Change
• Intervention / Treatment: Device: Pedra

Detailed Description

The Pedra perfusion system measures microvascular flow through diffuse speckle contrast analysis. It will be used to assess changes in perfusion in response to a number of physiological stimuli. It will be compared to other standard diagnostics including ankle-brachial index, toe-brachial index and transcutaneous oxygen measurement. Measurements will be undertaken in non-vascular patients as well as those with chronic limb threatening ischaemia.

• Study Type: Observational
• Enrollment (Anticipated): 50

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 90 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients with palpable pulses and patients with chronic limb threatening ischaemia

Description

Inclusion Criteria:

CLTI cohort

1. At least 40 years old
2. Each patient will have documented arterial occlusive disease within 6 weeks of enrolment as determined by an ankle-brachial index (ABI) < 0.7 but not greater than 1.2, toe-brachial index (TBI) <0.5, skin perfusion pressure (SPP) less than 30mmHg, OR Transcutaneous oxygen measurement (TCOM) < 40mmHg in diabetics and <30mmHg in non-diabetics.
3. The presence of skin breakdown compatible which with an underlying ischemic element (previous minor amputation for gangrene also included) that the Principle Investigator (PI) deems appropriate for the study.
4. Subject has read, understood and signed approved consent, and is willing to participate and comply with the study procedures and requirements.

Non-vascular group

1. At least 40 years old
2. Each patient will have documented palpable foot pulses
3. 21 patients will be free of lower limb oedema and 6 patients will have moderate oedema present
4. Subject has read, understood and signed approved consent, and is willing to participate and comply with the study procedures and requirements.

Exclusion Criteria:

CLTI Cohort

1. Subject on an investigational drug or therapeutic device within 30 days of the study visit, which in the view of the PI may compromise the study results.
2. Presence of a condition that PI considers will compromise the subject's ability to participate in the study.
3. Age <40 or >90
4. Inability to straight leg raise to 30 degrees or tolerate calf cuff occlusion.
5. Has smoked cigarettes/e-cigarettes on the day of testing.
6. Has taken caffeine drinks on the day of testing
7. In the last 3 hours the subject has exercised beyond normal daily walking.
8. Inability to have TBI measured (e.g. absence of toe)
9. Signs of active infection causing localised inflammation on the plantar or dorsal surfaces of the foot
10. Pathological skin conditions that may impair the ability of the adhesive sensor pads to adhere.

Non-vascular Cohort

1. Subject on an investigational drug or therapeutic device within 30 days of the study visit, which in the view of the PI may compromise the study results.
2. Presence of a condition that PI considers will compromise the subject's ability to participate in the study.
3. Age <40 or >90
4. Inability to straight leg raise to 30 degrees or tolerate calf cuff occlusion.
5. Has smoked cigarettes/e-cigarettes on the day of testing.
6. Has taken caffeine drinks on the day of testing
7. In the last 3 hours the subject has exercised beyond normal daily walking.
8. Inability to have TBI measured (e.g. absence of toe)
9. Signs of active infection causing localised inflammation on the plantar or dorsal surfaces of the foot
10. Pathological skin conditions that may impair the ability of the adhesive sensor pads to adhere.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Prospective

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Non vascular repeatibility; This cohort of patients with palpable pulses will be used to test inter- and intra- observer variability for the Pedra system	Device: Pedra; Diffuse speckle contrast analysis perfusion system
Non vascular physiology; This cohort of patients with palpable pulses will assess the ability of Pedra to detect perfusion changes in response to physiologic stimuli.	Device: Pedra; Diffuse speckle contrast analysis perfusion system
CLTI physiology; This cohort of patients with CLTI will assess the ability of Pedra to detect perfusion changes in response to physiologic stimuli.	Device: Pedra; Diffuse speckle contrast analysis perfusion system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Blood Perfusion Index (unitless number) delta in response to reduction in arterial inflow pressure	The range of change in the Blood Perfusion Index (unitless) in response to physiologic changes in arterial perfusion, in patients with healthy circulation and those with compromised arterial circulation	Intra-procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reliability of Blood Perfusion Index measurement will be assessed on repeated measures by determination of the correlation coefficient	The reliability of measurement of the Blood Perfusion Index will be measured and compared to standard diagnostics	intra-procedure
Repeatability of Blood Perfusion Index measurement will be assessed on repeated measures by determination of the correlation coefficient	The repeatability of measurement of the Blood Perfusion Index will be measured and compared to standard diagnostics	intra-procedure
Sensitivity of Pedra to detect differences in the Blood Perfusion Index between patient subsets	Use of a ROC curve to assess the ability of the Blood Perfusion Index to differentiate between those with healthy circulation and those with arterial disease	Intra-procedure

Collaborators and Investigators

• Sponsor: Pedra Technology, PTE LTD
• Collaborators: Serena Group

Study record dates

Study Major Dates

• Study Start (Anticipated): December 7, 2020
• Primary Completion (Anticipated): April 1, 2021
• Study Completion (Anticipated): July 1, 2021

Study Registration Dates

• First Submitted: November 5, 2020
• First Submitted That Met QC Criteria: November 13, 2020
• First Posted (Actual): November 16, 2020

Study Record Updates

• Last Update Posted (Actual): November 16, 2020
• Last Update Submitted That Met QC Criteria: November 13, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Keywords: Microvascular; Perfusion
• Other Study ID Numbers: Pedra-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: No plan to share data

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No