Time Course of Respiratory Oscillometry Parameters During Exposure to Nasal High-Flow Therapy in People With Stable Chronic Obstructive Pulmonary Disease: A Prospective Open-Label Single-Arm Physiological Study
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 发起方
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Change From Baseline in Frequency Dependence of Respiratory Resistance (R5-R20)
研究概览
简要总结
Chronic obstructive pulmonary disease (COPD) can affect the small airways and alter respiratory mechanics. Nasal high-flow therapy delivers warmed and humidified gas through nasal cannulas and may change airway resistance. Respiratory oscillometry is a noninvasive test that measures respiratory resistance and reactance during quiet breathing.
This prospective, single-center study will enroll 20 adults with severe or very severe stable COPD who have never used nasal high-flow therapy. During a single study visit lasting approximately 6 hours, participants will receive individualized nasal high-flow therapy for 4 hours. Respiratory oscillometry will be measured before exposure, immediately after device titration, and after 30, 60, 120, 180, and 240 minutes.
The primary objective is to describe the time course of the difference between respiratory resistance measured at 5 hertz and at 20 hertz (R5-R20), an indirect index of peripheral airway mechanical abnormalities. Secondary objectives are to describe changes in total and proximal respiratory resistance, respiratory reactance, resonant frequency, and area of reactance. The hypothesis is that nasal high-flow exposure will produce measurable, time-dependent changes in respiratory oscillometry parameters.
详细描述
NHFlOscillo is a prospective, open-label, single-center, single-arm physiological study involving adults with stable severe to very severe chronic obstructive pulmonary disease (COPD). The study is designed to characterize the time course of respiratory oscillometry parameters during a standardized 4-hour exposure to heated and humidified nasal high-flow therapy.
Participants will attend a single study visit and will be instructed to take their usual medications before the visit. After providing written informed consent, baseline characteristics will be recorded, and participants will complete the modified Medical Research Council Dyspnea Scale (mMRC), the St George's Respiratory Questionnaire (SGRQ), the COPD Assessment Test (CAT), and the Leicester Cough Questionnaire (LCQ). Baseline impulse oscillometry (IOS) will then be performed using a calibrated Vyntus IOS system, with the participant seated and breathing quietly, in accordance with current European Respiratory Society technical standards.
Nasal high-flow therapy will be initiated at a flow rate of 15 L/min and a temperature of 34 °C. After 3 minutes, the temperature will be increased to 37 °C if tolerated; otherwise, it will be maintained at 34 °C. The flow rate will then be increased every 3 minutes to an individualized level consistent with usual clinical practice, up to a maximum of 40 L/min. In participants receiving long-term oxygen therapy, supplemental oxygen will be titrated to maintain an oxygen saturation comparable to that observed under their usual conditions without nasal high-flow therapy.
The exposure will be continued for a total of 4 hours and will be briefly interrupted to perform oscillometry measurements immediately after titration and at 30, 60, 120, 180, and 240 minutes after the start of nasal high-flow therapy.
The target sample size is 20 participants. Changes in oscillometry parameters over time will be analyzed using linear mixed-effects models, with measurement time included as a fixed effect and participant included as a random effect. Each post-exposure time point will be compared with the pre-exposure baseline. Results will be reported as mean differences with 95% confidence intervals and interpreted according to the minimal clinically important difference for each outcome, when available.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age >18 years and <85 years;
- •Chronic obstructive pulmonary disease classified as Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometric grade III or IV;
- •Modified Medical Research Council dyspnea score ≥2;
- •Completed a pulmonary rehabilitation program at the study center;
- •Clinically stable, defined as no exacerbation and no treatment change during the previous 4 weeks;
- •With or without long-term oxygen therapy;
- •Never previously used nasal high-flow therapy;
- •Affiliated with a French social security system;
- •Able to read and understand the participant information and provide written informed consent.
- •Non-inclusion Criteria:
- •Under legal guardianship or curatorship;
- •Confirmed or suspected pregnancy;
- •Unable to provide informed consent;
- •Primary diagnosis of another chronic obstructive respiratory disease, such as asthma or primary bronchiectasis;
- •Severe or unstable cardiovascular disease, including uncontrolled cardiac arrhythmia, severe heart failure, recent myocardial infarction, or unstable angina;
- •Hemodynamic instability.
排除标准
- 未提供
研究组 & 干预措施
Nasal High-Flow Therapy
Participants receive individualized, heated and humidified nasal high-flow therapy (myAirvo 3, Fisher & Paykel Healthcare, New Zealand) for 4 hours during a single study visit, with repeated respiratory oscillometry assessments.
干预措施: Heated Humidified Nasal High-Flow Therapy (Device)
结局指标
主要结局
Change From Baseline in Frequency Dependence of Respiratory Resistance (R5-R20)
时间窗: Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.
Frequency dependence of respiratory resistance is calculated as respiratory resistance measured at 5 hertz minus respiratory resistance measured at 20 hertz (R5-R20). It is measured by impulse oscillometry using the Vyntus impulse oscillometry system (IOS) and expressed in kilopascals per liter per second (kPa/L/s). Percent-predicted values will also be reported when appropriate reference equations are available. The outcome is the change from the pre-exposure baseline at each post-baseline assessment during the exposure period. The registered measure is the repeated change from the pre-exposure baseline across the exposure period.
次要结局
- Change From Baseline in Total Respiratory Resistance at 5 Hz (R5)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Proximal Respiratory Resistance at 20 Hz (R20)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Respiratory Reactance at 5 Hz (X5)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Resonant Frequency (Fres)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Area of Reactance (AX)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Total Respiratory Resistance at 5 Hertz (R5)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Proximal Respiratory Resistance at 20 Hertz (R20)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)
- Change From Baseline in Respiratory Reactance at 5 Hertz (X5)(Baseline; immediately after individualized nasal high-flow titration; and 30, 60, 120, 180, and 240 minutes after starting nasal high-flow therapy.)