Finger Versus Earlobe Pulse Oximetry During the 6-Minute Walk Test in Interstitial Lung Disease
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Dual-site pulse oximetry (finger and earlobe).
- Who it may be relevant to
- Registry conditions: Interstitial Lung Disease (ILD), Idiopathic Pulmonary Fibrosis (IPF), Progressive Pulmonary Fibrosis, Connective Tissue Disease-Associated Interstitial Lung Disease. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Spain
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
A Prospective, Multicenter, Observational Method-Comparison Study of Finger Versus Earlobe Pulse Oximetry for Oxygen Saturation During the Six-Minute Walk Test in Patients With Interstitial Lung Disease (OXISITE-ILD)
Overview
The OXISITE-ILD study is a prospective, multicenter, observational study designed to evaluate the agreement between finger (digital) and earlobe (auricular) pulse oximetry for measuring oxygen saturation (SpO2) during the six-minute walk test (6MWT) in patients with interstitial lung disease (ILD). In routine clinical practice, exercise SpO2 is usually measured at the finger; however, the finger reading can be unreliable in some patients, and there is currently no recommendation on the best sensor location in ILD. This study compares the two sensor locations, recorded at the same time, and evaluates whether any disagreement changes how exercise desaturation is classified and whether ambulatory oxygen is indicated. All patients undergoing a 6MWT as part of routine ILD care are included consecutively to ensure a pragmatic, real-world representation of the ILD population. The primary objective is to measure the agreement between the two locations in the lowest SpO2 reached during the test, including the size and direction of any difference. Secondary objectives include the reclassification of patients at the clinical desaturation thresholds, the comparison between autoimmune and non-autoimmune ILD, the rate of invalid readings at each location, and the clinical, vascular and functional factors associated with disagreement.
Detailed description
OXISITE-ILD is a prospective, consecutive, multicenter, observational, cross-sectional method-comparison (agreement) study.
Each participant is assessed once, during a single 6MWT performed as part of routine care. SpO2 and heart rate are recorded simultaneously at the finger and at the earlobe with two pulse oximeters, at eight timepoints: baseline, each of minutes 1 to 6, and after a 2-minute recovery. The paired heart rate at each timepoint is used as a signal-quality control, so that agreement is assessed only on simultaneous, valid readings. In some participants, an arterial blood gas or a nailfold capillaroscopy may also be performed to help interpret the difference between locations.
A minimum of 100 participants is planned at the coordinating center, sufficient on its own for the primary objective; recruitment may be extended at the coordinating center and at the collaborating centers as the study requires. The participation of collaborating centers is opportunistic and adds precision, subgroup analyses, and external validity.
Interventions
- Other Dual-site pulse oximetry (finger and earlobe)
During a single 6MWT, SpO2 and heart rate are recorded simultaneously at the finger (digital) and the earlobe (auricular) with two pulse oximeters, at eight timepoints (baseline, minutes 1 to 6, and a 2-minute recovery). No treatment is administered and routine clinical management is not modified; the procedure adds the simultaneous earlobe measurement for comparison with the finger.
Primary outcome measures
- Intraclass correlation coefficient for agreement in minimum SpO2 between sensor locations [Time frame: Day 1]
- Bland-Altman agreement in minimum SpO2 between sensor locations [Time frame: Day 1]
Secondary outcome measures (6)
- Reclassification of exertional desaturation between sensor locations at SpO2 below 88% [Time frame: Day 1]
- Reclassification of exertional desaturation between sensor locations at SpO2 below 90% [Time frame: Day 1]
- Reclassification of exertional desaturation between sensor locations at a fall in SpO2 of 4% or more [Time frame: Day 1]
- Agreement in minimum SpO2 by autoimmune versus non-autoimmune ILD [Time frame: Day 1]
- Rate of invalid or poor-quality readings by sensor location [Time frame: Day 1]
- Clinical, vascular and functional predictors of discordance [Time frame: Day 1]
Eligibility criteria
Inclusion criteria
- Adults aged 18 years or older
- Confirmed diagnosis of interstitial lung disease (ILD) based on clinical, radiological and/or histological criteria
- Newly diagnosed or under follow-up for ILD
- Physically and cognitively able to perform the 6-minute walk test (6MWT)
- Signed informed consent
Exclusion criteria
- Inability to obtain a reliable, stable baseline pulse oximetry reading at the finger and/or the earlobe, preventing a valid paired baseline measurement and the calculation of agreement
- ILD exacerbation, decompensated comorbidity, or acute respiratory infection at the time of the test
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
Spain · 1 center
- Hospital de Granollers — Granollers
Identifiers
NCT: NCT07723872 · OXISITE-ILD