CO2 Rebreathing for Orthostatic Hypotension

This trial tests a new device that might help people with neurogenic orthostatic hypotension (nOH), a condition where standing causes a significant drop in blood pressure, leading to dizziness or fainting. The device, called a CO2 rebreather (or CO2 ReHaler), helps increase carbon dioxide levels, which may improve blood pressure when standing. Participants will breathe normally and then use the device to assess its effectiveness. People with a doctor-diagnosed nOH who don't smoke and can visit the University of Calgary might be suitable for this trial. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could enhance treatment options for nOH.

The trial does not specify if you need to stop taking your current medications, but it excludes those on medical therapies or medications that could interfere with testing of autonomic function. It's best to discuss your specific medications with the trial team.

Research shows that increasing carbon dioxide (CO2) intake can raise blood pressure in people with neurogenic orthostatic hypotension (nOH). This condition causes a significant drop in blood pressure upon standing, leading to symptoms like dizziness or fainting. The CO2 ReHaler captures exhaled CO2 and allows users to inhale it again, potentially improving blood pressure when standing.

Although specific safety data for CO2 therapy in nOH is lacking, past studies with healthy individuals have shown that small increases in inhaled CO2 are generally safe. This suggests the CO2 ReHaler could be safe for people with nOH, but further research is necessary to confirm this.

Researchers are excited about the CO2 ReHaler because it offers a novel approach to managing orthostatic hypotension. Unlike traditional treatments that often rely on medications to increase blood pressure, the CO2 ReHaler uses controlled CO2 rebreathing to elevate CO2 levels in the blood. This technique may enhance blood circulation and stabilize blood pressure when a person stands up. By focusing on a non-pharmacological method, the CO2 ReHaler has the potential to reduce side effects associated with drugs and provide a quick-acting solution to prevent dizzy spells and fainting episodes.

Research has shown that higher carbon dioxide (CO2) levels can raise blood pressure in people with neurogenic orthostatic hypotension (nOH). In past studies, patients with nOH experienced improved blood pressure when standing after inhaling more CO2. CO2 helps maintain steady blood pressure when standing, reducing symptoms like dizziness or fainting. In this trial, participants in the CO2 Rebreathing arm will use a CO2 rebreathing device, which allows them to inhale the CO2 they exhale, temporarily increasing CO2 levels. This simple method might help manage the blood pressure drop associated with nOH, offering a promising option for those affected by this condition.³⁴⁶⁷⁸