Does Severity of Airflow Obstruction Correlate to Static Lung Volumes

NCT05616780 | Completed

• 1 other identifier: 46246
• Study Type: interventional
• Target: 8
• Locations: 1 country
• Sites: 1

Brief Summary

Obstructive lung disease is defined by limitations in expiratory airflow, caused by excess mucus, loss of muscle tone, and structural changes. Over time airflow reduction can lead to gas trapping in the lungs (hyperinflation). Hyperinflation is linked to diminished exercise tolerance, shortness of breath, and a poor quality of life. Early treatment options include inhalers and pulmonary rehabilitation; however, surgical intervention and oxygen therapy may be required in the later stages. More prompt, accurate diagnosis will help to improve patient outcomes and optimise their treatment pathways. Two methodologies used to determine lung volumes and hyperinflation, are nitrogen washout and body plethysmography. The accuracy of each in defining lung volumes in patients with obstructive lung disease is debated in literature. Plethysmography requires the patient to sit in an enclosed box and perform a panting manoeuvre and uses measured changes in volume and pressure to derive lung volumes. Plethysmography has been suggested to overestimate lung volumes in patients with obstructive lung disease. On the other hand, nitrogen washout relies on 'washing out' all the nitrogen from the lungs to calculate lung volumes. Gas trapping and poor airflow circulation that occurs in patients with airflow obstruction may lead to underestimated lung volumes. This study will aim to investigate if there is a significant difference between lung volumes obtained by both nitrogen washout and body plethysmography in patients with obstructive lung disease. Subjects with mild, moderate, severe, and very severe obstruction, including those with no obstruction for comparison will be included, with approximately 10 from each group. They will be asked if they consent to undergo an extra test during their routine hospital appointment, which will add \~15 minutes to their visit.

Conditions

Pulmonary Disease, Chronic Obstructive

Keywords

airflow obstruction, plethysmography, lung volumes

Outcome Measures

Primary Outcomes (1)

• Measurement of lung volumes by two routine techniques in patients referred for pulmonary function testing.

  Patients referred for pulmonary function test as part of their routine patient treatment pathway will have lung volumes measured by nitrogen washout and body plethysmography, which are both routine techniques. Participants will have a range of obstructive or normal lung function. When the test is finished, patients will be told that their test results will be sent to their consultant, who will then explain them at a follow up appointment/ phone call (this is routine procedure).

  6 months

Study Arms (1)

Obtaining lung volume measurements in patients with airflow obstruction

OTHER

All patients involved in this study will be attending a pulmonary function test as part of their routine patient treatment pathway, requested by their consultant. Potential participants will be sent a patient information sheet prior to their lung function test. The pulmonary function test begins routinely, with the pre-test questions. Spirometry will then be performed. If the patient's results are variable and the repeatability criteria are not met, the patient will not be asked to take part in the study, and no additional tests (not requested by the consultant routinely) will be carried out. If the patient has normal or obstructive results (FEV1/FVC \<70%) the patient will sign the consent form and both lung volume tests will be conducted. They must be able to follow the instructions for both nitrogen washout and body plethysmography, and the results must also meet the acceptability and repeatability criteria.

Other: Physiological test

Interventions

Physiological test OTHER

Lung volume measurements will be obtained using nitrogen washout and body plethysmography

Obtaining lung volume measurements in patients with airflow obstruction

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• A minimum of 10 patients from each group will be included; normal lung function/ no airflow obstruction (FEV1/FVC \>70%), mild airflow obstruction (FEV1/FVC \<70% and FEV1 \>80% predicted), moderate airflow obstruction (FEV1/FVC \<70% and FEV1 50-80% predicted), severe airflow obstruction (FEV1/FVC \<70% and FEV1 30-50% predicted) and very severe (FEV1/FVC \<70% and FEV1 \>30% predicted).
• Al patients will be over the age of 18 with no upper age limit. No children will be included in this study.
• Patients must have withheld their inhalers.

You may not qualify if:

• \[15:10\] Jessica Armstrong
• Contraindications to performing the test include (if occurred within last 8 weeks):
• Heart attack
• Stroke
• Haemoptysis
• Pneumothorax
• Surgery to the abdomen/thorax
• Eye surgery
• An individuals spirometry cannot be included if:
• There is a cough during the first second of the manoeuvre
• A leak at the mouthpiece
• Early termination of manoeuvre
• Sub optimal effort
• They are unable to comprehend the instructions
• Obstruction of the mouthpiece (tongue/teeth)

Sponsors & Collaborators

• Virginia Hawkins: lead

Study Sites (1)

Shrewsbury and Telford hospital Trust

Telford, Shropshire, TF1 6TF, United Kingdom

Location

MeSH Terms

Conditions

Pulmonary Disease, Chronic Obstructive

Condition Hierarchy (Ancestors)

Lung Diseases, Obstructive; Lung Diseases; Respiratory Tract Diseases; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Nicholas John

  Shrewsbury and Telford Hospital Trust

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Chief Investigator

Study Record Dates

• First Submitted: November 8, 2022
• First Posted: November 15, 2022
• Study Start: March 16, 2023
• Primary Completion: April 28, 2023
• Study Completion: May 31, 2023
• Last Updated: March 29, 2024

Record last verified: 2024-03

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)