Intermittent Negative Pressure to Improve Blood Flow in Patients With Peripheral Artery Disease: Optimal Pulse Pressure Regime

Intermittent Negative Pressure to Improve Blood Flow in Patients With Peripheral Artery Disease. An Experimental Study to Investigate the Optimal Pulse Pressure Regime to Improve Blood Flow.

Recent studies have shown that applying intermittent negative pressure (INP) with short negative pressure (-40 mmHg) pulses to the lower extremities increase arterial blood flow velocity and skin blood flow. However, the optimal magnitude of negative pressure to improve blood flow is not known, and needs further investigation. Peripheral arterial blood flow velocity, skin blood flow and skin temperature in the foot will be recorded at different levels of oscillating negative pressure to identify a pressure range which is practically, while at the same time induce clinically relevant changes in blood flow parameters. Heart rate and blood pressure will be recorded to monitor the effects on the central circulation.

Study Overview

• Status: Completed
• Conditions: Intermittent Claudication; Peripheral Artery Disease; Lower Extremity Claudication
• Intervention / Treatment: Device: Intermittent negative pressure device

Detailed Description

Cross sectional study design. The equipment for physiological measurements will be attached to the patient, and the foot will then be placed in the pressure chamber. The device induces pulses of 10 sec negative pressure, and 7 sec of atmospheric pressure. Pressure levels of 0 mmHg, -10mmHg, -20 mmHg, -40 mmHg and -60 mmHg will be tested.

Patients will be recruited from the out-patient clinic at Department of Vascular Surgery, Oslo University Hospital, Aker.

Inclusion criteria:

Diagnosed peripheral artery disease (PAD), Ankle-Brachial Index <0.9 Outcome measures:

Arterial blood flow: Ultrasound Doppler from peripheral arteries in the foot.

Skin blood flow: Laser Doppler to measure acral skin blood perfusion.

Skin temperature

Systemic blood pressure: Finger arterial pressure will continuously be acquired by a photoplethysmographic pressure recording device (Finometer).

Ankle brachial index

Pressure recordings inside the pressure chamber: Continuously monitoring of pressure within the pressure chamber using a digital differential manometer.

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Norway
  • Oslo, Norway, 0586
    • Department of Vascular diseases, Oslo University Hosptital, Aker

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 96 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Diagnosed peripheral artery disease
• Ankle-Brachial Index <0.9

Exclusion Criteria:

• Incapable to make an informed consent
• Diagnosis of severe psychiatric disease
• Severe heart disease such as unstable angina pectoris, severe heart failure (NYHA IV), severe valve failure
• Systemic infection
• Use of vasoactive substances

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Optimal negative pulse pressure regime; The equipment for physiological measurements will be attached to the patient, and the foot will then be placed in the pressure chamber of the intermittent negative pressure device. The device induces pulses of 10 sec negative pressure, and 7 sec of atmospheric pressure. Pressure levels of 0 mmHg, -10 mmHg, -20 mmHg, -40 mmHg and -60 mmHg will be tested, with washout periods of 5 minutes between the different pressure levels. The order of the different negative pressure levels will be randomized to avoid causal interference.

Device: Intermittent negative pressure device; Pressure levels of 0 mmHg, -10 mmHg, -20 mmHg, -40 mmHg and -60 mmHg will be tested, with washout periods of 5 minutes between the different pressure levels

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Arterial blood flow	Continuously Ultrasound Doppler measurements of the dorsalis pedis artery or tibialis posterior artery to monitor changes in arterial blood flow during 5 min sequences of intermittent negative pressure treatment. Pressure levels of 0, -10 mmHg, -20 mmHg, -40 mmHg and -60 mmHg will be tested. Systolic pressures in the arm and the ankle will be assessed before the intervention to describe the patients severity of disease.	At time of intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Skin blood flow	Continuously Laser Doppler measurements from the pulp of the first toe to monitor changes in acral skin perfusion during 5 min sequences of intermittent negative pressure treatment. Pressure levels of 0, -10 mmHg, -20 mmHg, -40 mmHg and -60 mmHg will be tested.	At time of intervention

Collaborators and Investigators

• Sponsor: Oslo University Hospital
• Collaborators: Otivio AS
• Investigators: Principal Investigator: Jonny Hisdal, PhD, Department of Vascular diseases, Oslo University Hospital, Aker

Study record dates

Study Major Dates

• Study Start (Actual): May 15, 2018
• Primary Completion (Actual): September 30, 2018
• Study Completion (Actual): January 31, 2019

Study Registration Dates

• First Submitted: May 22, 2018
• First Submitted That Met QC Criteria: June 5, 2018
• First Posted (Actual): June 6, 2018

Study Record Updates

• Last Update Posted (Actual): December 4, 2019
• Last Update Submitted That Met QC Criteria: December 3, 2019
• Last Verified: December 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Atherosclerosis; Peripheral Vascular Diseases; Peripheral Arterial Disease; Intermittent Claudication
• Other Study ID Numbers: SD0321063

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No