Controlled CO2 Inhalation in NOH

Not Applicable

Not yet recruiting

• Conditions: Neurogenic Orthostatic Hypotension

• Registration Number: NCT06751888
• Lead Sponsor: University of Calgary

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.

Detailed Description

Not available

Study Timeline

• Status Verified: 2024-12
• Study First Submitted: 2024-12-20
• Study First Submitted QC: 2024-12-20
• Last Update Submitted: 2024-12-20
• Study First Posted: 2024-12-30
• Last Update Posted: 2024-12-30
• Study Start: 2025-05-01
• Primary Completion: 2028-12-31
• Study Completion: 2028-12-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 28

Inclusion Criteria

• 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.

Exclusion Criteria

• 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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Magnitude of the systolic blood pressure (SBP) response	Start of in-lab study day to the end of the in-lab study day	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.

Secondary Outcome Measures

Name	Time	Method
Change in Cerebral Blood Flow (ΔCBFv)	Start of in-lab study day to the end of the in-lab study day	Secondary outcome measures will be the change in Cerebral Blood Flow (ΔCBFv) for each arm of the study.
Change in Vanderbilt Orthostatic Symptom Scores (ΔVOSS)	Start of in-lab study day to the end of the in-lab study day	Secondary outcome measures will be the change in Vanderbilt Orthostatic Symptom Scores (ΔVOSS) for each arm of the study.

Trial Locations

Locations (1)

University of Calgary; 🇨🇦 Calgary, Alberta, Canada