Controlled CO2 Inhalation in NOH

NCT06751888 | Not Yet Recruiting

• 1 other identifier: REB24-1780
• Study Type: interventional
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

This study focuses on neurogenic orthostatic hypotension (nOH), which is a disorder characterized by an abnormal drop in blood pressure (BP) within 3-minutes of standing. Patients with nOH experience debilitating symptoms including light-headedness, falls, and fainting. Patients often struggle with day-to-day tasks that require standing, with a reduced quality-of-life. Current therapies for nOH have limited effectiveness and unwanted side effects. Our lab has found that raising blood CO2 levels (hypercapnia) in the lab increases BP when standing in patients with nOH. We now aim to test the CarboHaler, an exogenous controlled CO2 delivery device, in this study to see if increasing CO2 levels through controlled CO2 inhalation can improve BP and reduce symptoms in patients with nOH when standing up. On the study day, participants will undergo two Head-up Tilt (HUT; upright) tests with different breathing protocols: one with and one without exogenous CO2 delivery provided by a CO2 inhalational device. We will record heart rate, blood pressure, and breathing parameters. We will also assess upright symptoms using the Vanderbilt Orthostatic Symptoms Score. Our primary outcome is the magnitude of the change in systolic BP from lying down to standing, which will be compared with and without exogenous CO2 delivery. We hypothesize that exogenous CO2 delivery provided by a CO2 inhalational device will raise CO2 enough to increase standing BP, which could reduce the debilitating symptoms experienced by patients with nOH. We hope that these data will support future clinical trials, with the long-term goal of creating a simple, low-cost treatment for increasing quality-of-life for patients with nOH.

Conditions

Neurogenic Orthostatic Hypotension

Keywords

Neurogenic Orthostatic Hypotension; Autonomic; Cardiovascular; Therapies; Quality-of-life; Symptom-management; Novel

Outcome Measures

Primary Outcomes (1)

• Magnitude of the systolic blood pressure (SBP) response

  The primary outcome measures will be the magnitude of the systolic blood pressure (SBP) response (ΔSBP = Head Up Tilt - Supine) during 0% CO2 vs. Controlled CO2 inhalation.

  Start of in-lab study day to the end of the in-lab study day

Secondary Outcomes (2)

• Change in Cerebral Blood Flow (ΔCBFv)

  Start of in-lab study day to the end of the in-lab study day

• Change in Vanderbilt Orthostatic Symptom Scores (ΔVOSS)

  Start of in-lab study day to the end of the in-lab study day

Study Arms (2)

0% CO2 Arm

SHAM COMPARATOR

In this arm, participants will breathe with the CO2 delivery device providing no exogenous CO2 while supine and during a 10-min HUT test.

Device: Controlled CO2 delivery (Sham)

Controlled CO2 Inhalation Arm

EXPERIMENTAL

In this arm, participants will breathe with the CO2 delivery device in the supine position until BP levels increase. Once a BP increase is observed, participants will be tilted upright and will continue to breathe with the inhalation device during a 10-min HUT test.

Other: Controlled CO2 delivery

Interventions

Controlled CO2 delivery OTHER

The use of a controlled CO2 delivery offers a straightforward way to increase arterial CO2. Controlled CO2 inhalation may offer a novel hemodynamic therapy for patients with Neurogenic Orthostatic Hypotension

Controlled CO2 Inhalation Arm

Controlled CO2 delivery (Sham) DEVICE

For this intervention, we will be using this device set at 0% CO2 for our sham comparison.

0% CO2 Arm

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years
• Male and Female
• Physician diagnosis of Neurogenic Orthostatic Hypotension
• Non-smokers.
• Able and willing to provide informed consent.
• Ability to travel to Libin Cardiovascular Institute Autonomic Testing Lab at the University of Calgary, Calgary, AB.

You may not qualify if:

• Pregnant or breast-feeding females
• Subjects with chronic heart failure or severe pulmonary disease who are unable to climb one flight of stairs due to shortness of breath.
• Presence of failure of other organ systems or systemic illness that can affect autonomic function or the participant's ability to cooperate. These include dementia, alcohol and/or drug abuse.
• Other factors which in the investigator's opinion would prevent the participant from completing the protocol, including poor compliance during previous studies.

Sponsors & Collaborators

• University of Calgary: lead

Study Sites (1)

University of Calgary

Calgary, Alberta, T2N 4Z6, Canada

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 20, 2024
• First Posted: December 30, 2024
• Study Start: May 1, 2025
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2028
• Last Updated: December 30, 2024

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)