UMIN-ICDS Clinical Trial

Public title

A study using electrical impedance tomography to assess lung ventilation and its changes with body positioning and noninvasive ventilation in patients with acute respiratory failure in the emergency department

Acronym

Yamagata ED-EIT Study

Scientific Title

Electrical impedance tomography assessment of changes in regional lung ventilation associated with respiratory effort, body positioning, and noninvasive positive-pressure ventilation in patients with acute respiratory failure transported to the emergency department: a prospective observational study

Scientific Title:Acronym

Yamagata ED-EIT Study

Region

Japan

Condition

Acute respiratory failure in patients presenting to the emergency department

Classification by specialty

Pneumology	Emergency medicine	Intensive care medicine

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

This study aims to prospectively evaluate changes in regional lung ventilation assessed using electrical impedance tomography (EIT) in patients with acute respiratory failure presenting to the emergency department, in relation to respiratory effort, clinically indicated changes in body position, and the initiation of noninvasive positive-pressure ventilation (NPPV). The primary objective is to determine the change in the proportion of ventilation reaching dependent lung regions from immediately before to 15 minutes after NPPV initiation. Secondary objectives are to evaluate temporal changes in EIT parameters through 60 minutes after NPPV initiation and to explore their associations with respiratory effort, body positioning, and clinical outcomes, including NPPV failure within 48 hours.

Basic objectives2

Others

Basic objectives -Others

Physiological assessment of regional lung ventilation using EIT and exploratory analysis of its association with clinical outcomes, including NPPV failure

Trial characteristics_1

Exploratory

Trial characteristics_2

Explanatory

Developmental phase

Not applicable

Primary outcomes

Change in the proportion of ventilation reaching the dependent lung region [delta Zdependent/delta Zglobal (%), principally the dorsal region of interest] from immediately before to 15 minutes after NPPV initiation, measured in the same body position and at the same EIT electrode-belt position

Key secondary outcomes

1. Changes in center of ventilation (CoV), global inhomogeneity (GI) index, end-expiratory lung impedance (EELI), regional ventilation delay (RVD), silent spaces, pendelluft, and tidal impedance variation (TIV) in each region of interest immediately before and at 15 and 60 minutes after NPPV initiation
2. Changes in regional lung ventilation distribution from immediately before to 5 to 15 minutes after clinically indicated changes in body position
3. Associations of EIT parameters with respiratory rate, dyspnea, accessory respiratory muscle use, paradoxical breathing, P0.1 when available, and expiratory tidal volume
4. Changes in SpO2, PaO2/FiO2 ratio, PaCO2, pH, heart rate, and blood pressure immediately before and at 15 and 60 minutes after NPPV initiation
5. EIT measurement success rate, proportion of analyzable waveforms, electrode-belt application time, reasons for missing measurements, and EIT measurement-related adverse events
6. Associations between early changes in EIT parameters and NPPV failure within 48 hours, tracheal intubation within 7 days, intensive care unit admission, duration of mechanical ventilation, hospital length of stay, in-hospital mortality, and outcomes at 90 days after enrollment
NPPV failure is defined as the need for tracheal intubation within 48 hours after NPPV initiation because of worsening respiratory status, impaired consciousness, hemodynamic instability, or intolerance of NPPV.

Study type

Observational

Basic design

Randomization

Randomization unit

Blinding

Control

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

Purpose of intervention

Type of intervention

Interventions/Control_1

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

Not applicable

Gender

Male and Female

Key inclusion criteria

Patients aged 18 years or older who are transported to or present at the emergency department of Yamagata University Hospital.
Patients with acute respiratory failure who require oxygen therapy, HFNC, or NPPV and are considered by the attending physician suitable for EIT measurement during spontaneous breathing.
Written informed consent is obtained from the patient or a legally acceptable representative.
At least one analyzable EIT waveform at T0 and respiratory physiological parameters recorded at the same time are available.

Key exclusion criteria

Patients requiring immediate tracheal intubation or another invasive procedure because of cardiopulmonary arrest, impending respiratory arrest, shock, or another critical condition in which EIT application could interfere with emergency care.
Patients in whom the EIT electrode belt cannot be safely applied because of chest trauma, burns, extensive skin lesions, a chest tube fixation site, or another relevant condition.
Patients with a contraindication or exclusion specified in the instructions for use of the EIT device, including implanted electronic devices when applicable.
Patients from whom an analyzable EIT signal cannot be obtained because of severe agitation, excessive body movement, or body habitus.
Patients who lack decision-making capacity and for whom written informed consent cannot be obtained from a legally acceptable representative within the enrollment period.
Patients with a do-not-intubate (DNI) decision in place at the time of enrollment.
Patients considered unsuitable for participation by the principal investigator or attending physician.

Target sample size

80

Name of lead principal investigator

1st name	Tadahiro
Middle name
Last name	Kobayashi

Organization

Yamagata University Faculty of Medicine

Division name

Department of Emergency and Critical Care Medicine

Zip code

990-9585

Address

2-2-2 Iida-Nishi, Yamagata City, Yamagata 990-9585, Japan

TEL

023-628-5422

Email

ta-kobayashi@med.id.yamagata-u.ac.jp

Name of contact person

1st name	Tadahiro
Middle name
Last name	Kobayashi

Organization

Yamagata University Faculty of Medicine

Division name

Department of Emergency and Critical Care Medicine

Zip code

9909585

Address

2-2-2 Iida-Nishi, Yamagata, Yamagata-pref, Japan

TEL

0236285422

Homepage URL

Email

ta-kobayashi@med.id.yamagata-u.ac.jp

Institute

Yamagata University

Institute

Department

Personal name

Organization

Yamagata University Faculty of Medicine

Organization

Division

Category of Funding Organization

Self funding

Nationality of Funding Organization

Japan

Co-sponsor

Name of secondary funder(s)

Organization

Ethics Review Committee, Faculty of Medicine, Yamagata University

Address

2-2-2 Iida Nishi, Yamagata City, Yamagata 990-9585, Japan

Tel

023-628-5047

Email

yu-ikekenkyu@jm.kj.yamagata-u.ac.jp

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

山形大学医学部附属病院（山形県）

Date of disclosure of the study information

2026

Year

10

Month

16

Day

URL releasing protocol

Publication of results

Unpublished

URL related to results and publications

Number of participants that the trial has enrolled

Results

Results date posted

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Participant flow

Adverse events

Outcome measures

Plan to share IPD

No public sharing of individual participant data is planned.

IPD sharing Plan description

Individual participant data will not be made publicly available in a repository because of participant privacy and the scope of informed consent. Data from participants who consent to secondary use may be used for future research within the scope of consent only after separate ethics review and institutional approval.

Recruitment status

Preinitiation

Date of protocol fixation

2026

Year

08

Month

19

Day

Date of IRB

2026

Year

09

Month

15

Day

Anticipated trial start date

2026

Year

10

Month

20

Day

Last follow-up date

2029

Year

06

Month

29

Day

Date of closure to data entry

2029

Year

09

Month

30

Day

Date trial data considered complete

2029

Year

12

Month

31

Day

Date analysis concluded

2030

Year

03

Month

31

Day

Other related information

This is a single-center, prospective observational study of adult patients with acute respiratory failure who are transported to or present at the emergency department of Yamagata University Hospital. EIT will be used to assess changes in regional lung ventilation associated with respiratory effort, clinically indicated changes in body position, and initiation of NPPV. The attending physician will determine oxygen therapy, HFNC, NPPV, body position, and tracheal intubation as part of routine clinical care, and EIT findings will not be used for treatment decisions. The primary outcome is the change in the proportion of ventilation reaching dependent lung regions from immediately before to 15 minutes after NPPV initiation. Up to 80 patients will be enrolled, with a target of at least 40 patients with analyzable EIT data before and after NPPV initiation. Associations between early EIT changes and clinical outcomes, including NPPV failure, will be analyzed on an exploratory basis.

Registered date

2026

Year

10

Month

16

Day

Last modified on

2026

Year

10

Month

16

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072481