Physiology and Structure of the Small Airways in Patients With Chronic Airflow Obstruction or COVID-19

Imperial College London42 enrolled

Overview

The purpose of this research project is to study small airways physiological function in patients with chronic obstructive lung disease or COVID-19 and explore the relationship with in-vivo microanatomical small airway structure as measured by OCT. Correlating endobronchial assessment with multiple breath nitrogen washout and impulse oscillometry will allow the characterisation of the relationship between small airway structural findings and these validated investigations. A small volume lung wash, endobronchial brushings and the collection of a limited number of endobronchial cryobiopsy samples will be performed to better understand the endobronchial environment of the small airways through inflammatory studies. Following the completion of any such work, residual samples will be stored in a "bio-bank" to enable the completion of future work. Understanding the relationship with symptom-based quality of life scoring questionnaires and a functional assessment of exercise capacity will help elucidate the clinical impact of in-vivo small airways findings.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Copd COVID-19 Asthma Small Airways Disease

Eligibility

Sex: ALLMin age: 16 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Age 16 or over 2. Scheduled for bronchoscopy as part of clinical care or research protocol 3. No bleeding diathesis or therapeutic anticoagulation 4. COPD: * FEV1/FVC ratio \<70% or Asthma: * Diagnosed by standard clinical methods * Post-bronchodilator FEV1 ≥60% predicted or COVID-19 infection or previous COVID-19 infection (confirmed as per local guidelines) Exclusion Criteria: 1. Unable to provide informed consent 2. Exacerbation of obstructive airways disease or respiratory infection requiring systemic antibiotics or corticosteroids in the 6 weeks prior to enrolment unless suffering from COVID-19 infection and bronchoscopy is required for clinical reasons 3. Contra-indications to performing lung function testing * Aortic aneurysm \>6cm * Unstable cardiovascular disease (unstable angina, myocardial infarction or pulmonary embolism \<4 weeks prior) * Severe aortic stenosis * Pneumothorax * Cerebral aneurysm * Thoracic or abdominal surgery \<4 weeks prior 4. Contra-indications to passing oesophageal balloons * Oesophageal ulceration or varices * Sinusitis, recent nasal surgery or epistaxis

Outcomes

Primary Outcomes

Respiratory resistance at 5Hz - 20Hz (R5-R20) (kPa/l/s) related to airtrapping as determined by quantitative CT (Expiratory phase low attenuation area <856 HU (%LAA <856 HU)

Impulse Oscillometry

Time frame: Baseline, pre-procedure

Secondary Outcomes

Respiratory reactance at 5Hz: X5 (kPa/l/s)

Impulse Oscillometry

Time frame: Baseline, pre-procedure

Reactance area: Ax (kPa/l/s)

Impulse Oscillometry

Time frame: Baseline, pre-procedure

Functional residual capacity by MBNW: FRCgas (L)

Multiple Breath Nitrogen Washout

Time frame: Baseline, pre-procedure

Lung clearance index: LCI

Multiple Breath Nitrogen Washout

Time frame: Baseline, pre-procedure

Ventilation heterogeneity conducting airways: Scond (L/s)

Multiple Breath Nitrogen Washout

Time frame: Baseline, pre-procedure

Ventilation heterogeneity acinar airways: Sacin (L/s)

Multiple Breath Nitrogen Washout

Time frame: Baseline, pre-procedure

Forced expiratory volume in 1 second: FEV1 (L)

Spirometry

Time frame: Baseline, pre-procedure

Forced vital capacity: FVC (L)

Spirometry

Time frame: Baseline, pre-procedure

Total lung capacity: TLC (L)

Plethysmography

Time frame: Baseline, pre-procedure

Residual volume: RV (L)

Plethysmography

Time frame: Baseline, pre-procedure

Functional residual capacity by plethysmography: FRCpleth (L)

plethysmography

Time frame: Baseline, pre-procedure

Airway mean luminal diameter (Dmean)

Optical Coherence Tomography

Time frame: Baseline, during the procedure

Airway inner lumen area (Ai)

Optical Coherence Tomography

Time frame: Baseline, during the procedure

Airway wall area (Aw), airway wall percentage (Aw%) as determined by [Aw/(Ai + Aw) × 100%]

Optical Coherence Tomography

Time frame: Baseline, during the procedure

Air trapping - expiratory phase low attenuation area <856 HU (%LAA <856 HU)

Quantitative CT

Time frame: Baseline, pre-procedure

Modified MRC dyspnoea score

Patient reported outcome measure

Time frame: Baseline, pre-procedure

St George's Respiratory Questionnaire Score

Patient reported outcome measure

Time frame: Baseline, pre-procedure

Asthma-related Quality of Life Questionnaire (AQLQ) (if asthmatic)

Patient reported outcome measure

Time frame: Baseline, pre-procedure

Asthma Control Questionnaire (ACQ) (if asthmatic)

Patient reported outcome measure

Time frame: Baseline, pre-procedure

6-minute walk distance (m)

Time frame: Baseline, pre-procedure

Physiology and Structure of the Small Airways in Patients With Chronic Airflow Obstruction or COVID-19

Overview

Conditions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts