Effect of Smoking on Ventilation-Perfusion Ratio

NCT02963467 | Unknown

• 1 other identifier: 1133/2013
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Smoking is one of the world's leading health hazards. Besides being a major risk factor in the etiology of COPD and lung cancer, cigarette smoke is also a causative agent lung diseases characterized by bronchiolar and interstitial inflammation. However, the associated lung pathology of smoking is not only a risk in the development of lung diseases, but also widely recognized as a major risk factor associated with perioperative respiratory and cardiovascular complications. Apart from the long term effects of cigarette smoke, acute effects of the inhalation of cigarettes smoke may influence the course of lung pathology. The inhalation of smoke causes inflammation in the lung by inducing chemotaxis and activation of neutrophils and macrophages and induces oxidative stress. As the acute inflammatory response to smoke inhalation seems to be the underlying mechanism for chronic diseases of smokers, exploring the field of the acute pulmonary changes after exposure to cigarette smoke is highly relevant. One reason for acute hypoxia and injury during smoking might be a severe mismatch of ventilation and perfusion of the lung. Using the multiple inert gas elimination technique (MIGET), a distribution of ventilation-perfusion ratios in the lung can be calculated by analyzing data on the retention and excretion of six infused inert gases. A saline solution containing the gases is infused intravenously. When passing through the lung the gases are either eliminated from the blood or retained depending on their partition coefficient and local V/Q ratio. The concentrations of the gases are measured in the mixed venous blood or the mixed expired gas and the arterial blood allowing for the calculation of retention and excretion and the derivation of V/Q distribution. MIGET is the experimental gold standard to determine the Ventilation-Perfusion ratio of the lung. The aim of this study is to show the acute effect of smoking on ventilation/perfusion ratio distribution in the lung in otherwise healthy smokers.

Conditions

Lung Disease

Keywords

multiple inert gas elimination technique; smoking; pulmonary disorder

Outcome Measures

Primary Outcomes (1)

• ventilation-perfusion ratio by MMIMS-MIGET

  V/Q-ratio as well as shunt, low V/Q, normal V/Q and high V/Q i.e. deadspace will be assessed by micropore-membrane inlet mass-spectrometry multiple inert gas elimination technique (MMIMS-MIGET)

  within a time-frame of 6 hours

Secondary Outcomes (1)

• serum nicotine by blood sampling

  within a time-frame of 6 hours

Study Arms (3)

Healthy Volunteers - non-smokers

OTHER

control group: After baseline measurements V/Q will be measured by MIGET. After a 2 hour wash out period, the Volunteers will smoke a dummy cigarette. Then V/Q will be measured again after 15 minutes.

Procedure: "dummy cigarette"

Healthy Volunteers - occasional smokers

OTHER

intervention: After baseline measurements V/Q will be measured by MIGET. After a 2 hour wash out period, the Volunteers will smoke 4 conventional cigarettes. Thereafter, V/Q will be measured again after 15, 30, 45, 60 and 120 minutes.

Procedure: cigarette

Healthy Volunteers - heavy-smokers

OTHER

intervention: After baseline measurements V/Q will be measured by MIGET. After a 2 hour wash out period, the Volunteers will smoke 4 conventional cigarettes. Thereafter, V/Q will be measured again after 15, 30, 45, 60 and 120 minutes.

Procedure: cigarette

Interventions

cigarette PROCEDURE

smoking 4 conventional cigarettes

Also known as: smoking

Healthy Volunteers - heavy-smokers; Healthy Volunteers - occasional smokers

"dummy cigarette" PROCEDURE

smoking a "dummy cigarette"

Also known as: smoking

Healthy Volunteers - non-smokers

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• normal body mass index (BMI)

You may not qualify if:

• Medical history of pulmonary or cardiovascular disease
• Family history of malignant hyperthermia, neuro-muscular disorders
• Known hypersensitivity to any of the inert gases or substances administered
• History of post operative nausea and vomiting
• Pregnancy (pregnancy test will be performed on study day)

Sponsors & Collaborators

• Medical University of Vienna: lead

Study Sites (1)

Medical University of Vienna

Vienna, 1090, Austria

RECRUITING

MeSH Terms

Conditions

Lung Diseases; Smoking

Interventions

Tobacco Products; Smoking Devices

Condition Hierarchy (Ancestors)

Respiratory Tract Diseases; Behavior

Intervention Hierarchy (Ancestors)

Manufactured Materials; Technology, Industry, and Agriculture

Central Study Contacts

Stefan Boehme, Ass.-Prof. Dr.

CONTACT

00436766767144; stefan.boehme@meduniwien.ac.at

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistent Professor

Study Record Dates

• First Submitted: November 4, 2016
• First Posted: November 15, 2016
• Study Start: September 17, 2018
• Primary Completion: August 1, 2019
• Study Completion: September 1, 2019
• Last Updated: March 14, 2019

Record last verified: 2019-03

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1)