The Use of FlowMet-R Technology to Predict Wound Healing in CLI Patients in a Wound Care Center Setting

The Use of FlowMet-R Technology to Predict Wound Healing in Critical Limb Ischemia (CLI) Patients in a Wound Care Center Setting

Single-institution, prospective nonrandomized pilot study of critical limb ischemia patients with planned lower extremity revascularization will undergo Flowmet-D measurements in a wound care center setting to determine threshold values associated with wound healing and amputation. A subset of patients will undergo hyperbaric oxygen therapy and will have Flowmet-D measurements to determine those who respond best to therapy.

Study Overview

• Status: Enrolling by invitation
• Conditions: Critical Limb Ischemia
• Intervention / Treatment: Diagnostic test: Flowmet-D; Diagnostic test: ABI

Detailed Description

A single-institution, prospective nonrandomized pilot study will be conducted at Stanford Hospital and the Stanford Advanced Wound Care Center (AWCC). Patients with CLTI by WIfI criteria (ABI or toe pressures) and a concomitant non-healing lower extremity wound will be recruited. Inclusion criteria will include CLTI, at least one active lower extremity wound and planned lower extremity revascularization. ABI/TBIs will be recorded preintervention, post intervention and at one and three month intervals. Intraprocedural characteristics including the number and location of vessels revascularized, patent runoff vessels pre and post procedure, pedal arch anatomy and presence of angiographic "blush" to wound will be documented.

Post-operatively, patients will be followed at the AWCC where they will receive standard of care wound management including offloading, regular debridement, infection and edema management. FlowMet-R perfusion values will be obtained prerevascularization, immediately post revascularization as well as weekly at each follow up AWCC visit for a total of up to 6 months or until wound healing.Wound size will be recorded.

Patients who undergo hyperbaric oxygen therapy (at the discretion of AWCC surgeon) will have perfusion values performed before and after hyperbaric oxygen therapy sessions 1, 2, 10, 20, 30 and 40. Hyperbaric oxygen therapy will be conducted 5 days a week for duration of 90 minutes. Patients who undergo other advanced wound care treatments such as stem cell therapies or skin substitutes will also received FlowMet-R prior to and after treatment. Primary outcomes will be wound healing defined as complete skin epithelialization, wound improvement rate, major and minor amputations as well as need for repeat revascularization.

• Study Type: Observational
• Enrollment (Anticipated): 100

Contacts and Locations

Study Locations

• United States
  • California
    • Stanford, California, United States, 94061
      • Stanford Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

The CLI population is individuals with CLTI, at least one active lower extremity wound and planned lower extremity revascularization. The HBO cohort is a subset of the CLI population who will undergo HBO therapy post-revascularization.

Description

Inclusion Criteria:

CLI Cohort:

• CLI by WIfI criteria (ABI or toe pressures)
• Non-healing lower extremity wound
• Planned lower extremity revascularization
• Able to provide informed consent
• Able to comply with study procedures

HBO Cohort:

• All of the above
• Enrolled in HBO therapy post revascularization (at the discretion of the provider)

Exclusion Criteria:

• Under 30
• Wound not suitable for FlowMet-D probe attachment

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
CLI (Critical Limb Ischemia); CLI cohort is a population of individuals with CLI, at least one active lower extremity wound and planned lower extremity revascularization. CLI cohort patients will receive Flowmet-D measurements in addition to standard of care therapy following intervention.	Diagnostic test: Flowmet-D; Flowmet-D is a non-invasive device that measures blood flow.; Diagnostic test: ABI; ABI is the ratio of the systolic blood pressure measured at the ankle to that measured at the brachial artery and is considered the gold standard for the diagnosis of peripheral artery disease.
HBO (Hyperbaric Oxygen); HBO cohort is a subset of the CLI cohort who will undergo hyperbaric oxygen therapy in the post-operative setting who will receive Flowmet-D measurements before and after their therapy.	Diagnostic test: Flowmet-D; Flowmet-D is a non-invasive device that measures blood flow.; Diagnostic test: ABI; ABI is the ratio of the systolic blood pressure measured at the ankle to that measured at the brachial artery and is considered the gold standard for the diagnosis of peripheral artery disease.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Wound Healing	Wound Healing, defined as complete skin epithelialization, will be associated with Flowmet-D measurements.	6 months
Wound Improvement	Wound Improvement, defined as improvement in wound size, will be associated with Flowmet-D values.	6 months
Major Amputation	Major amputation, defined as amputation above the ankle joint, will be associated with Flowmet-D values.	6 months
Minor Amputation	Minor amputation, defined as amputation below the ankle joint, will be associated with Flowmet-D values.	6 months
Repeat Revascularization	Repeat Revascularization, defined as unplanned repeat lower extremity revascularization, will be monitored.	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Response to Hyperbaric Oxygen Therapy	Response to Hyperbaric Oxygen Therapy, will be defined as improved perfusion (improved Flowmet-D value) following therapy	6 months

Collaborators and Investigators

• Sponsor: Stanford University
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI); Medtronic Endovascular
• Investigators: Principal Investigator: Venita Chandra, MD, Stanford University

Study record dates

Study Major Dates

• Study Start (ACTUAL): April 27, 2022
• Primary Completion (ANTICIPATED): September 1, 2023
• Study Completion (ANTICIPATED): September 1, 2023

Study Registration Dates

• First Submitted: December 14, 2021
• First Submitted That Met QC Criteria: July 7, 2022
• First Posted (ACTUAL): July 13, 2022

Study Record Updates

• Last Update Posted (ACTUAL): July 13, 2022
• Last Update Submitted That Met QC Criteria: July 7, 2022
• Last Verified: July 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Ischemia
• Other Study ID Numbers: 62133; 5R38HL143615-02 (NIH)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

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.: Yes