The association between various diagnostic measurements and lung function

ISRCTN ISRCTN45778591
DOI https://doi.org/10.1186/ISRCTN45778591
Secondary identifying numbers PFT_Prosp_Amendment 01
Submission date
14/02/2020
Registration date
08/06/2020
Last edited
04/04/2025
Recruitment status
Recruiting
Overall study status
Ongoing
Condition category
Respiratory
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
The main function of lungs is gas exchange through gas transport. Due to the complexity of the lung structure, gas transport can only be optimized to a certain extent and is easily affected by changes in the small airways.
The overall aim of this study is to prospectively associate various pulmonary function tests with clinical, laboratory, histological and radiological characteristics.

Who can participate?
People aged 18 years or above.

What does the study involve?
Participants will undergo several lung function tests during a single visit.

What are the possible benefits and risks of participating?
None.

Where is the study run from?
University Hospital Basel, Clinic for Respiratory Medicine and Pulmonary Cell Research (Switzerland)

When is the study starting and how long is it expected to run for?
April 2019 to April 2028

Who is funding the study?
University Hospital Basel (Switzerland)

Who is the main contact?
Prof. Daiana Stolz
daiana.stolz@usb.ch

Contact information

Prof Daiana Stolz
Scientific

University Hospital of Basel
Clinic for Respiratory Medicine and Pulmonary Cell Research
Petersgraben 4
Basel
4031
Switzerland

ORCiD logoORCID ID 0000-0003-0099-882X
Phone +41 612654422
Email daiana.stolz@usb.ch
Dr Vivian Suarez Domenech
Scientific

Universitätsspital Basel
Pneumologie
Petersgraben 4
Basel
4031
Switzerland

Phone +41 61 328 69 17
Email vivian.suarezdomenech@usb.ch

Study information

Study designObservational longitudinal study
Primary study designObservational
Secondary study designLongitudinal study
Study setting(s)Hospital
Study typeScreening
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titlePulmonary function test association with clinical, laboratory, histological and radiological characteristics – a prospective study
Study acronymN2
Study objectivesThe overall aim of this study is to prospectively associate various pulmonary function tests with clinical, laboratory, histological and radiological characteristics.
Ethics approval(s)Approved 22/02/2019, EKNZ (Ethics Committee Northern and Central Switzerland, Hebelstrasse 53, Basel 4056, Switzerland; +41 612681350; eknz@bs.ch), ref : 2018-0286, Amendment approved 27/11/2019
Health condition(s) or problem(s) studiedRespiratory diseases
InterventionNon-invasive measurements specific to the project and performed in all participants, include:
N2 washout (single and multiple breath):
Single breath - the measurements are carried out with the patient sitting upright and breathing normally. The test subjects breathe through a mouthpiece with a nose clamp that is attached to the measuring device. A bacteria filter is installed upstream of the measuring device. The filter, mouthpiece and nose clip are replaced after each patient. The measurement device is based on an ultrasonic flow head, the Exhalyzer® (Eco Medics AG, Dürnten, Switzerland), connected to a bypass element that provides constant air intake. The gas used as part of the study (100% O2, DTG) is supplied to the patient via this bypass element. During the measurement procedure, the accurate recording of the flow volume curve and the gas signals (O2, CO2 and the derived N2, molar mass signal) enable good online monitoring of the measurement quality. Any changes to the patient’s breathing pattern, hyperventilation or leaks are identified immediately and the measurement procedure is terminated.
Multiple breath - for N2 MBW, the supply of 100% O2 flushes out the nitrogen in the lungs. The test ends when < 2% end-expiratory N2 (1/40 of the starting concentration) is reached over three consecutive breaths. For the evaluation, all signals are aligned in terms of time, and the respiratory flows and derived breathing volumes are corrected for body temperature, ambient pressure and humidity. To calculate the functional residual capacity (FRC), the ratio (net volume of expirated tracer gas) / [(end-expiratory N2 concentration at start of washout measurement) – (end-expiratory N2 concentration at end of the washout measurement)] is calculated. Over the course of the three requisite measurements per patient, the FRC must not deviate by more than 20%; otherwise, the measurement must be rejected. The LCI is calculated via FRC as the ratio of the cumulative expirated volume.
Forced oscillation technique (FOT) - the sound waves, generated with the help of a loudspeaker are transmitted into the lungs of the subject. These sound waves, which are essentially pressure waves, cause changes in the pressure and this change in pressure drives changes in airflow. By measuring the magnitude of change in the pressure and flow, one can determine the mechanical properties of the lung. Waves of lower frequencies travel deep into the lungs till and into the alveoli and are reflected back while those of higher frequencies are reflected from the larger airways. Thus, the parameters calculated at different frequencies give measures of different regions in the lungs.
Aeonose – Measured data consists of an individual breath-print of volatile organic compounds. Patients breathe into the portable Aeonose for five minutes. The system learns from each data entered and is updating consistently. The device is CE-certified and therefore there is no risk in using it for our patients.
Sleepiz One – A contactless, non-invasive device that measures vital parameters while patient is at rest. It is a radar-based sensor that does not pose any risks. The electromagnetic emission is around 100 times lower than that of a typical mobile phone.
Along with the study-specific interventions, routine interventions such as body plethysmography are also performed.
Intervention typeOther
Primary outcome measureMeasured at a single time point:
1. LCI measured using the multiple-breath nitrogen washout (N2-MBW)
2. Phase III slope (SIII) measured using the single-breath nitrogen washout (N2-SBW) and single-breath double tracer gas washout (DTG-SBW)
Secondary outcome measuresMeasured at a single time point:
1. Scond, Sacin, area under the curve of DTG-SBW measured using the multiple-breath nitrogen washout (N2-MBW)
2. Bronchoprovocation test outcomes such as PD20 and PD40
3. Volatile organic compounds in the breath measured using Aeonose
4. Sleepiz One measurements (breathing, heart rate, movement during sleep)
5. Known clinical, laboratory, histological and radiological characteristics measured using patient records
Overall study start date01/04/2019
Completion date30/04/2028

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participants20000
Key inclusion criteria1. Older than 18 years
2. Capable to perform an acceptable spirometry
3. Able to answer questionnaires
4. With or without respiratory symptoms
5. With or without diagnosed respiratory disease
Key exclusion criteriaDoes not meet inclusion criteria
Date of first enrolment01/04/2019
Date of final enrolment30/04/2028

Locations

Countries of recruitment

  • Switzerland

Study participating centre

University Hospital Basel
Clinic for Respiratory Medicine and Pulmonary Cell Research
Petersgraben 4
Basel
4031
Switzerland

Sponsor information

University Hospital of Basel
Hospital/treatment centre

Clinic for Respiratory Medicine and Pulmonary Cell Research
Petersgraben 4
Basel
4031
Switzerland

Phone +41 612654422
Email daiana.stolz@usb.ch
Website https://www.unispital-basel.ch/
ROR logo "ROR" https://ror.org/04k51q396

Funders

Funder type

Hospital/treatment centre

University Hospital Basel

No information available

Results and Publications

Intention to publish date30/04/2029
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planPlanned publication in a high-impact peer-reviewed journal.
IPD sharing planThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Protocol file version v5 27/11/2019 03/07/2020 No No
Results article 03/04/2025 04/04/2025 Yes No

Additional files

ISRCTN45778591_PROTOCOL_v5_27Nov2019.pdf
Uploaded 03/07/2020

Editorial Notes

04/04/2025: Publication reference added.
04/12/2024: Contact details updated.
04/04/2023: The recruitment end date was changed from 30/04/2023 to 30/04/2028.
22/03/2023: Contact details updated.
21/03/2023: The following changes were made to the trial record:
1. The overall trial end date was changed from 30/04/2023 to 30/04/2028.
2. The intention to publish date was changed from 30/04/2024 to 30/04/2029.
03/07/2020: Uploaded protocol Version 5, 27 November 2019 (not peer reviewed).
17/04/2020: Trial’s existence confirmed by Ethics Committee Northern and Central Switzerland