Advertisement

Topics

The Cyclocapnic Method for Measurement of Chemosensitivity

2014-07-23 21:11:07 | BioPortfolio

Summary

We aim to test our method for measuring chemosensitivity (the ventilatory response to a change in carbon dioxide), which uses sinusoidal carbon dioxide stimuli.

Hypotheses:

- Carbon dioxide sensitivity is dependent on the cycle time over which we administer the gas (frequency).

- Chemoreflex gain decreases as deadspace increases.

Description

We will apply a new method for the measurement of chemosensitivity (how sensitive a person is to changes in carbon dioxide), which is one of the principle determinants of whether people with heart failure develop abnormal breathing patterns We have shown in a pilot study that administering sinusoidal patterns of inspired carbon dioxide produces similar sinusoidal responses in ventilation. We aim to test our method for measuring chemosensitivity, which uses sinusoidal carbon dioxide stimuli (similar to those that drive the oscillations in ventilation found in periodic breathing). We aim to show that how the cycle time of carbon dioxide administered affects the resulting ventilatory oscillations and therefore that when measuring the chemoreflex clinically, it is important to deliver carbon dioxide stimuli that replicate the cycle time of oscillations in carbon dioxide seen in periodic breathing (typically approximately one minute).

Study Design

Control: Historical Control, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Basic Science

Conditions

Periodic Breathing

Intervention

carbon dioxide

Location

St Mary's Hospital
London
United Kingdom
W2 1LA

Status

Recruiting

Source

Imperial College London

Results (where available)

View Results

Links

Published on BioPortfolio: 2014-07-23T21:11:07-0400

Clinical Trials [756 Associated Clinical Trials listed on BioPortfolio]

Carbon Dioxide Insufflation Colonoscopy in IBD Patients

Carbon dioxide insufflation during colonoscopy significantly reduces discomfort (pain, bloating and flatulence) after the procedure. So far, it has not been studied in inflammatory bowel d...

Dynamic Carbon Dioxide (CO2) Administration for Sleep Apnoea

Normally breathing is controlled by a reflex that responds to the levels of carbon dioxide (CO2) in the blood. In heart failure, where the heart muscle is damaged and therefore does not pu...

Carbon Dioxide Insufflation on Cerebral Microemboli

The purpose of this study is to determine if blowing carbon dioxide into the surgical field during open-heart surgery to displace retained chest cavity air from the atmosphere will decreas...

Prospective, Non-Randomized Evaluation of Carbon Dioxide Gas as a Contrast Agent in Comparison With Iodinated Contrast in Endovascular Aneurysm Repair

Endovascular repair of infrarenal abdominal aortic aneurysms (AAA) requires a contrast agent to identify the vascular anatomy and placement of the stent graft. Iodine contrast has traditi...

Effect of Patient Position on Arterial, End-tidal and Transcutaneous Carbon Dioxide

Investigators evaluate the effect of patient position (Trendelenburg and reverse Trendelenburg) on arterial, end-tidal and transcutaneous carbon dioxide partial pressure in patients underg...

PubMed Articles [4711 Associated PubMed Articles listed on BioPortfolio]

Supplemental Carbon Dioxide Stabilizes the Upper Airway in Volunteers Anesthetized with Propofol.

Propofol impairs upper airway dilator muscle tone and increases upper airway collapsibility. Preclinical studies show that carbon dioxide decreases propofol-mediated respiratory depression. We studied...

End-tidal carbon dioxide levels in patients with post-concussion syndrome during neurocognitive and physical tasks compared to a normative control group.

Recent findings suggest breathing may negatively affect performance after concussion. The aim of the study was to examine group differences between individuals with and without post-concussion syndrom...

Caffeine and supplemental oxygen effectively suppress periodic breathing with only minor effects during long episodes of apnoea in preterm infants.

We investigated the characteristics and effects of sleep stage, supplemental oxygen and caffeine on periodic breathing (PB) and apnoea of prematurity (AOP) in preterm infants.

Umpolung Reactivity of Aldehydes toward Carbon Dioxide.

Carbon dioxide is an intrinsically stable molecule. Therefore, its activation requires extra energy input in the form of reactive reagents and/or activated catalysts and, often, harsh reaction conditi...

A Two-Step Process of Nitrous Oxide before Carbon Dioxide for Humanely Euthanizing Piglets: On-Farm Trials.

Current methods of euthanizing piglets are raising animal welfare concerns. Our experiment used a novel two-step euthanasia method, using nitrous oxide (N₂O) for six minutes and then carbon dioxide ...

Medical and Biotech [MESH] Definitions

An enzyme with high affinity for carbon dioxide. It catalyzes irreversibly the formation of oxaloacetate from phosphoenolpyruvate and carbon dioxide. This fixation of carbon dioxide in several bacteria and some plants is the first step in the biosynthesis of glucose. EC 4.1.1.31.

Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).

A family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. They play an important role in the transport of CARBON DIOXIDE from the tissues to the LUNG. EC 4.2.1.1.

A pulmonary ventilation rate faster than is metabolically necessary for the exchange of gases. It is the result of an increased frequency of breathing, an increased tidal volume, or a combination of both. It causes an excess intake of oxygen and the blowing off of carbon dioxide.

Catalyzes the decarboxylation of an alpha keto acid to an aldehyde and carbon dioxide. Thiamine pyrophosphate is an essential cofactor. In lower organisms, which ferment glucose to ethanol and carbon dioxide, the enzyme irreversibly decarboxylates pyruvate to acetaldehyde. EC 4.1.1.1.

More From BioPortfolio on "The Cyclocapnic Method for Measurement of Chemosensitivity"

Advertisement
Quick Search
Advertisement
Advertisement

 

Searches Linking to this Trial