The Effect of Oscillation and Lung Expansion (OLE) Therapy in Prolonged Mechanical Ventilated Patients With Atelectasis Evaluated in Multiple Methods

The Efficacy of Oscillation and Lung Expansion (OLE) Therapy Evaluated by Compterized Tomography (CT) and Electrical Impedance Tomography（EIT）in Prolonged Mechanical Ventilated Patients With Atelectasis: A Multicenter Randomized Contralled Trial

High frequency chest wall oscillation (HFCWO) is currently one of the most common and widespread mechanical airway clearance techniques (ACTs) in clinical practice in China. As an external airway oscillation technique, it has been proven in previous clinical practices that it can help clear secretions by vibrating the chest wall, loosening the secretions adhering to the airway walls and promoting ciliary movement, thereby improving lung ventilation and re-expansion. However, there are still some groups of patients for whom this technique is not suitable in clinical practice, such as those who are uncomfortable with the oscillation, have damaged skin on the chest and back, have unstable rib fractures, or have poorly positioned tracheostomy tubes. In recent years, integrating multiple techniques into a single treatment has become a trend. Among them, oscillation and lung expansion (OLE) combines continuous positive airway pressure (CPAP), continuous high-frequency oscillation (CHFO), and nebulization, which can effectively clear airway secretions and promote lung re-expansion. Currently, only a few studies have confirmed that OLE has a positive impact on improving respiratory function in patients with acute respiratory failure, severe burns, and after lung surgery.

This study aims to further compare the effects of the above two mechanical ACTs on improving lung ventilation and re-expansion by electrical impedance tomography (EIT), and optimize the clinical practice of physical therapists.

Study Overview

• Status: Recruiting
• Conditions: Atelectasis
• Intervention / Treatment: Other: High frequency chest wall oscillation or other airway clearance therapy; Other: Oscillation and lung expansion

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shuo Chen; Phone Number: +86 13521362894; Email: 983340122@qq.com

Study Locations

• China
  • Beijing, China
    • Completed
    • Shuo Chen
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100144
      • Recruiting
      • Respiratory rehabilitation center
      • Contact: Shuo Chen; Phone Number: 010-56981092

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years old
• The following characteristics of high mucus secretion in the airway occur along with pulmonary infection: coughing up a large amount of white sticky phlegm, yellow phlegm or yellow purulent phlegm; Phlegm sounds can be heard in the lungs. The frequency of sputum aspiration is higher than once every 4 hours
• Tracheotomy time ≥7 days
• Vital signs are stable.

Exclusion Criteria:

• Hemodynamic instability
• Inhaled oxygen concentration (FiO2) > 60%
• Untreated pneumothorax
• Patients who have undergone total pneumonectomy
• Hemoptysis
• Pulmonary bullae, etc.
• Patients with delirium and restlessness

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Coventional therapy group; This group conducted casual treatment and airway clearance (except oscillation an lung expansion therapy)	Other: High frequency chest wall oscillation or other airway clearance therapy; High frequency chest wall oscillation (HFCWO) is an external airway oscillation technique, it has been proven in previous clinical practices that it can help clear secretions by vibrating the chest wall, loosening the secretions adhering to the airway walls and promoting ciliary movement, thereby improving lung ventilation and re-expansion. We will give the patients HFCWO twice a day and each time we will give them 15HZ as frequency and 20mins as time. Other therapies are postural drainage, manual vibration...
Experimental: OLE group; This group conducted casual treatment and oscillation an lung expansion on daily therapy	Other: High frequency chest wall oscillation or other airway clearance therapy; High frequency chest wall oscillation (HFCWO) is an external airway oscillation technique, it has been proven in previous clinical practices that it can help clear secretions by vibrating the chest wall, loosening the secretions adhering to the airway walls and promoting ciliary movement, thereby improving lung ventilation and re-expansion. We will give the patients HFCWO twice a day and each time we will give them 15HZ as frequency and 20mins as time. Other therapies are postural drainage, manual vibration...; Other: Oscillation and lung expansion; oscillation and lung expansion (OLE) combines continuous positive airway pressure (CPAP), continuous high-frequency oscillation (CHFO), and nebulization, which can effectively clear airway secretions and promote lung re-expansion. The OLE will be given to the patients twice a day as well, and each time 10mins therapy with 2.5mins CPAP and 2.5mins CHFO cirsularly.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Atelectatic Lung Area on Chest CT	Atelectatic lung area will be quantified on chest computed tomography (CT) images by a blinded radiologist using imaging analysis software. The primary outcome is the change in atelectatic lung area from baseline to 10 days post-treatment. The unit of the measures is Square centimeters (cm²)	Baseline and 10 days post-treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ventilation distribution on Electrical impedance tomography (EIT) evaluation	electrical impedance tomography will be used to evaluated the ventilation : Select a large, medium, or small electrode belt according to the patient's body size and place it on the chest (at the level of the 4th-5th intercostal spaces). Ensure that the belt position remains consistent for each measurement. Inject current through the electrode belt and measure the corresponding voltage to reconstruct the intrathoracic impedance distribution and display the corresponding images. Continuously record for 90 seconds and store the EIT data. Global inhomogeneity(GI) value describe the ventilation dstribute, the value is more closer to 0.25, is better.	at admission and 3days/7days/10 days after treatment
Lung Ultrasound score(LUS)	Lung aeration will be assessed using the Lung Ultrasound Score (LUS).Scan 12 areas to get a relevent score for degrees of lung aeration of each area according the patterns that we got on the lung ultrasound. Each lung region will be scored according to standard criteria, and the total score will be calculated. The outcome measure is the change in total LUS from baseline to 10 days post-treatment. Score ranged from 0 to 36.Higher scores indicate worse lung aeration.	at admission and 10 days after treatment
Oxygenation index	Oxygenation index is measured by fingertip blood oxygen and is expressed as a percentage.	at admission and 10 days after treatment
the score on Modified Borg dyspnea scale	a number that reflect the degree of dyspnea on patient reporting according to the Modified Borg dyspnea scale	at admission and 10 days after treatment
The Clinical Pulmonary Infection Score	The Clinical Pulmonary Infection Score (CPIS) is a pulmonary infection assessment system formed by integrating multiple clinical indicators such as body temperature, white blood cell count, and oxygenation index,scaled from 0 to 12, the higher scores, the higher risk of infection.	from enrollment to 2 weeks after the treatment
daily cost	Daily cost in HDU was calculated by a speciallist nurse and is expressd as Chinese yuan	in 10 days after admission

Collaborators and Investigators

• Sponsor: Capital Medical University

Study record dates

Study Major Dates

• Study Start (Estimated): March 15, 2026
• Primary Completion (Estimated): April 1, 2026
• Study Completion (Estimated): October 1, 2026

Study Registration Dates

• First Submitted: December 30, 2025
• First Submitted That Met QC Criteria: February 28, 2026
• First Posted (Actual): March 5, 2026

Study Record Updates

• Last Update Posted (Actual): March 5, 2026
• Last Update Submitted That Met QC Criteria: February 28, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Atelectasis; electrical impedance tomography; oscillation and lung expansion; high frequency chest wall
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Pulmonary Atelectasis; Therapeutics; Respiratory Therapy; Chest Wall Oscillation
• Other Study ID Numbers: 20251211001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No