EIT-Guided Visual Feedback During Incentive Spirometry for Postoperative Atelectasis

NCT07681232 | Not Yet Recruiting

• 1 other identifier: KY2026002
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This single-center randomized controlled trial will evaluate whether real-time visual feedback from electrical impedance tomography (EIT) improves the immediate distribution of lung ventilation during incentive spirometry in adults with postoperative atelectasis. Approximately 60 participants will be randomized 1:1 to receive either EIT-guided visual feedback or standardized verbal guidance during one session of 30 incentive-spirometry breaths. The primary outcome is the change in dorsal ventilation fraction from before training to 5 minutes after training. Secondary outcomes include inspiratory capacity, ventilation homogeneity, dependent silent spaces, end-expiratory lung impedance, oxygenation, in-hospital intubation or reintubation, and intervention-related adverse events.

Conditions

Postoperative Atelectasis

Keywords

Electrical Impedance Tomography; Incentive Spirometry; Visual Feedback; Pulmonary Rehabilitation; Dorsal Ventilation

Outcome Measures

Primary Outcomes (1)

• Change in Dorsal Ventilation Fraction

  Dorsal ventilation fraction is the percentage of tidal ventilation occurring in the dorsal lung region during stable spontaneous breathing. The outcome is calculated as DVF at T1 minus DVF at T0 using 2-minute EIT recordings and a fixed offline analysis algorithm. Higher values indicate a greater shift of ventilation toward the dorsal region.

  Baseline and 5 minutes after completion of the single intervention session

Secondary Outcomes (6)

• Mean Inspiratory Volume

  Day 1, during the single intervention session of 30 incentive-spirometry breaths

• Change in Global Inhomogeneity Index

  Baseline and 5 minutes after completion of the single intervention session

• Change in End-Expiratory Lung Impedance

  Baseline and 5 minutes after completion of the single intervention session

• Change in Dependent Silent Spaces

  Baseline and 5 minutes after completion of the single intervention session

• Change in Oxygen Saturation to Inspired Oxygen Ratio

  Baseline and 5 minutes after completion of the single intervention session

Other Outcomes (4)

• Intervention-Related Adverse Events

  From the start of the single intervention session through 24 hours after completion of the session

• Change in PaO2/FiO2 Ratio

  Baseline and 5 minutes after completion of the single intervention session, when routine arterial blood gas data are available

• ICU Length of Stay

  From ICU admission through ICU discharge, up to 30 days

Study Arms (2)

EIT-Guided Visual Feedback

EXPERIMENTAL

Participants complete one standardized session of incentive spirometry while viewing the real-time EIT screen. Trained staff provide target-directed feedback to increase ventilation in dependent dorsal lung regions.

Behavioral: EIT-Guided Incentive Spirometry

Standardized Verbal Guidance

ACTIVE COMPARATOR

Participants complete the same standardized session of incentive spirometry with the EIT screen concealed. Trained staff provide standardized verbal instructions without imaging feedback.

Behavioral: Standardized Incentive Spirometry Guidance

Interventions

EIT-Guided Incentive Spirometry BEHAVIORAL

Participants perform three sets of 10 incentive-spirometry breaths while viewing real-time electrical impedance tomography images. Trained staff provide standardized, target-directed feedback to increase ventilation in dependent dorsal lung regions.

EIT-Guided Visual Feedback

Standardized Incentive Spirometry Guidance BEHAVIORAL

Participants perform three sets of 10 incentive-spirometry breaths with the EIT screen concealed. Trained staff provide standardized verbal instructions on posture, slow sustained inspiration, a 2- to 3-second breath hold, and rest between breaths, without imaging feedback.

Standardized Verbal Guidance

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older.
• Admitted to an intensive care unit or postoperative monitoring unit after major thoracic or upper-abdominal surgery; tracheal tube removed; spontaneously breathing; and clinically stable.
• Alert and able to understand and follow incentive-spirometry and EIT instructions.
• Bedside lung ultrasound shows atelectasis or markedly reduced aeration in dorsal or posterolateral lung regions, with the lung-ultrasound assessment recorded.
• Baseline EIT during quiet breathing in a semi-recumbent position shows insufficient dorsal ventilation with potential for improvement; dorsal ventilation fraction below 50%.
• Written informed consent provided by the participant or legally authorized representative according to the ethics-approved process, with participant re-consent when decision-making capacity returns.

You may not qualify if:

• Ongoing invasive mechanical ventilation or noninvasive ventilation, or high-flow nasal oxygen when study conditions cannot be maintained stably.
• Hemodynamic instability or inability to tolerate a semi-recumbent position.
• Inability to cooperate with training or impaired consciousness.
• Unsuitable for EIT monitoring, including an implanted pacemaker or defibrillator incompatible with the device, severe skin disease at the electrode-belt site, or known relevant allergy.
• Severe underlying pulmonary disease likely to substantially affect ventilation distribution and obscure the intervention effect.
• Chest-wall deformity or severe scoliosis affecting EIT image quality.
• Body mass index greater than 35 kg/m2.
• Pregnancy or breastfeeding.
• Current participation in another interventional clinical trial that could interfere with study outcomes.
• Any other condition that, in the investigator's judgment, makes participation inappropriate.

Sponsors & Collaborators

• Shanghai Zhongshan Hospital: lead

Study Sites (1)

Zhongshan Hospital, Fudan University

Shanghai, Shanghai Municipality, 200032, China

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Participants and bedside intervention staff cannot be masked because the experimental group views the EIT screen. EIT data analysts and outcome assessors remain blinded to group assignment.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants are randomized 1:1 to EIT-guided visual feedback or standardized verbal guidance during a single session of incentive spirometry.

Study Record Dates

• First Submitted: June 9, 2026
• First Posted: July 2, 2026
• Study Start: July 1, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: July 2, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)