TOMCAT: Non-invasive Measurement of Cerebral Dynamic Autoregulation

• Sponsor: University of Pennsylvania (Other)
• Overall Status: Completed
• CT.gov ID: NCT02442856
• Collaborator: (none)
• Enrollment: 21
• Location: 1
• Arm: 1
• Actual Duration (Months): 57
• Patients Per Site Per Month: 0.4

Study Details

Study Description

Brief Summary

The overall objective of this study is to evaluate the use of diffuse correlation spectroscopy to non-invasively measure dynamic cerebral autoregulation in subjects with vascular risk factors. Optical cerebral blood flow measurements will be correlated with changes in arterial blood pressure to assess how CBF is maintained in response to changes in ABP, and will be compared to transcranial doppler reference measurements.

Condition or Disease	Intervention/Treatment	Phase
Stroke	Device: Thigh Cuff	N/A

Study Design

• Study Type: Interventional
• Actual Enrollment: 21 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Other
• Actual Study Start Date: Jun 1, 2015
• Actual Primary Completion Date: Mar 1, 2019
• Actual Study Completion Date: Mar 1, 2020

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Intervention We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.	Device: Thigh Cuff

Outcome Measures

Primary Outcome Measures

1. dCA Measurement During Acute Changes in Mean Arterial Pressure, TCD [1.5 hours]

   Rate of Regulation, measured using transcranial doppler. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.

2. dCA Measurement During Acute Changes in Mean Arterial Pressure, Optical [1.5 hours]

   Rate of Regulation, measured using diffuse correlation spectroscopy. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.

Other Outcome Measures

1. Linear Relationship Between Rate of Regulation Measured Using TCD and Optics [1.5 hours]

   Linear relationship between Rate of Regulation measured using TCD and Optics, expressed as slope of linear fit

Eligibility Criteria

Criteria

• Ages Eligible for Study: 50 Years and Older
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• Age greater than or equal to 50 years

• Positive history of at least one of the following vascular disk factors: hypertension, diabetes, hyperlipidemia, coronary artery disease, atrial fibrillation, prior myocardial infarct, transient ischemic attack, or history of smoking

Exclusion Criteria:

• Vascular risk factor subjects:

1. Pregnant women

2. Prisoners

3. Prior neurosurgical procedure or traumatic brain injury, including hemicraniectomy or other skull defect

4. Prior history of ischemic or hemorrhagic stroke

5. Prior lower extremity amputation

6. Peripheral vascular disease

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Hospital of the University of Pennsylvania	Philadelphia	Pennsylvania	United States	19104

Sponsors and Collaborators

• University of Pennsylvania

Investigators

None specified.

Study Documents (Full-Text)

• Study Protocol, Statistical Analysis Plan, and Informed Consent Form - Mar 17, 2016

More Information

Publications

None provided.

• Responsible Party: University of Pennsylvania
• ClinicalTrials.gov Identifier: NCT02442856
• Other Study ID Numbers: 821705
• First Posted: May 13, 2015
• Last Update Posted: Aug 14, 2020
• Last Verified: Aug 1, 2020

Study Results

Participant Flow

Arm/Group Title	Intervention
Arm/Group Description	We will measure dynamic cerebral autoregulation (dCA) with both transcranial doppler (TCD) and diffuse correlation spectroscopy (DCS) during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
Period Title: Overall Study
STARTED	21
COMPLETED	21
NOT COMPLETED	0

Baseline Characteristics

Arm/Group Title	Intervention
Arm/Group Description	We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
Overall Participants	21
Age (years) [Median (Inter-Quartile Range) ]
Median (Inter-Quartile Range) [years]	31
Sex: Female, Male (Count of Participants)
Female	9 42.9%
Male	12 57.1%
Race and Ethnicity Not Collected (Count of Participants)

Outcome Measures

1. Primary Outcome

Title	dCA Measurement During Acute Changes in Mean Arterial Pressure, TCD
Description	Rate of Regulation, measured using transcranial doppler. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.
Time Frame	1.5 hours

Outcome Measure Data

Analysis Population Description

21 subjects consented, hemodynamic monitoring possible in 18. 1 subject did not tolerate,data acquisition was unsuccessful in 2. In 3 subjects, the pressure algorithm to isolate cerebral blood flow(CBF) was unsuccessful. In 4 subjects, BP did not decrease following cuff deflation due to technical issues leaving 11 subjects in the final analysis

Arm/Group Title	Intervention
Arm/Group Description	We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
Measure Participants	11
Number (95% Confidence Interval) [per second]	0.262

2. Primary Outcome

Title	dCA Measurement During Acute Changes in Mean Arterial Pressure, Optical
Description	Rate of Regulation, measured using diffuse correlation spectroscopy. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.
Time Frame	1.5 hours

Outcome Measure Data

Analysis Population Description

21 subjects in the study, but hemodynamic monitoring was only possible in 18. 1 subject did not tolerate, and data acquisition was unsuccessful in 2. In 3 subjects, the pressure algorithm to isolate CBF was unsuccessful. In 4 subjects, BP did not decrease following cuff deflation due to technical issues leaving 11 subjects in the final analysis

Arm/Group Title	Intervention
Arm/Group Description	We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
Measure Participants	11
Number (95% Confidence Interval) [per second]	0.278

3. Other Pre-specified Outcome

Title	Linear Relationship Between Rate of Regulation Measured Using TCD and Optics
Description	Linear relationship between Rate of Regulation measured using TCD and Optics, expressed as slope of linear fit
Time Frame	1.5 hours

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Intervention
Arm/Group Description	We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
Measure Participants	11
Number [slope]	0.96

Adverse Events

Time Frame	Duration of study, which was approximately 6 months.
Arm/Group Title	Intervention
Arm/Group Description	We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.
All Cause Mortality
	Intervention
	Affected / at Risk (%)	# Events
Total	0/21 (0%)
Serious Adverse Events
	Intervention
	Affected / at Risk (%)	# Events
Total	0/21 (0%)
Other (Not Including Serious) Adverse Events
	Intervention
	Affected / at Risk (%)	# Events
Total	0/21 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.