Saline Contrast Electrical Impedance Tomography Method for Diagnosis of Acute Pulmonary Embolism

NCT07190079 | Recruiting DMC

• 1 other identifier: ECTPED
• Study Type: observational
• Target: 343
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this observational study is to compare the consistency of saline contrast Electrical Impedance Tomography(EIT) method and Computed Tomography Pulmonary Angiography (CTPA) in diagnosing acute pulmonary embolism. The main question it aims to answer is: Can bedside saline contrast EIT method be used for the diagnosis of acute pulmonary embolism? The participants will undergo saline contrast EIT and CTPA examinations successively within 24 hours.

Conditions

Acute Pulmonary Embolism

Outcome Measures

Primary Outcomes (1)

• The ability of proportion of dead space ventilation to diagnose PE

  The participant undergoes a saline contrast EIT examination, after which the distribution of pulmonary ventilation and perfusion will be obtained, respectively. A V-Q map will be subsequently generated. Using offline EIT data analysis tool, the proportion of lung regions with ventilation but without perfusion is calculated, representing the proportion of dead space ventilation (expressed as a percentage). Area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, Youden's index, accuracy, Kappa statistic, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) will be used to evaluate the ability of proportion of dead space ventilation to diagnose acute pulmonary embolism (PE).

  Within 24 hours before or after the CTPA examination

Secondary Outcomes (3)

• The ability of proportion of V/Q matching to diagnose PE

  Within 24 hours before or after the CTPA examination

• The ability of proportion of shunt to diagnose PE

  Within 24 hours before or after the CTPA examination

• The ability of other indicators reflecting pulmonary ventilation and perfusion to diagnose PE

  Within 24 hours before or after the CTPA examination

Study Arms (1)

Patients clinically suspected with acute PE

This study will enroll adult patients (\>18 years) with clinically suspected or confirmed acute pulmonary embolism (PE) presenting with acute respiratory failure, who either undergo computed tomography pulmonary angiography (CTPA) within 24 hours or are scheduled for CTPA within the next 24 hours. Eligible participants need to have an indwelling central venous catheter (internal jugular or subclavian vein) or a peripheral forearm venous line, with no restrictions on gender.

Diagnostic Test: Saline contrast Electrical Impedance Tomography method; Diagnostic Test: Computed Tomography Pulmonary Angiography (CTPA)

Interventions

Saline contrast Electrical Impedance Tomography method DIAGNOSTIC_TEST

This study will enroll patients with clinically suspected or confirmed acute pulmonary embolism (PE) presenting with acute respiratory failure, who undergo electrical impedance tomography (EIT) with saline contrast within 24 hours before or after computed tomography pulmonary angiography (CTPA). The EIT procedure is performed as follows: 1. Breath-Hold Maneuver: (1)Spontaneous breathing patients: Supine position, instructed to hold expiration for ≥8 seconds. (2)Mechanically ventilated patients: Expiratory hold (\>8 sec) achieved via ventilator; deeper sedation will be applied when feasible to prolong breath-hold. 2. Venous Access: (1)Preferred: Central venous catheter (internal jugular or subclavian vein).(2)Alternative: Peripheral forearm vein (preferably the median cubital vein). 3. Contrast Administration:(1)Central venous route: 10 mL of 10% NaCl.(2)Peripheral venous route: 15 mL of 5% NaHCO₃.

Patients clinically suspected with acute PE

Computed Tomography Pulmonary Angiography (CTPA) DIAGNOSTIC_TEST

Patients who meet the inclusion criteria will undergo CTPA examination using conventional clinical diagnostic methods.

Patients clinically suspected with acute PE

Eligibility Criteria

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

Study Population

Patients with clinically suspected or confirmed acute pulmonary embolism (PE) presenting with acute respiratory failure.

You may qualify if:

• Patients with clinically suspected or confirmed acute pulmonary embolism (PE) presenting with acute respiratory failure;
• Availability of CTPA results within 24 hours or scheduled to undergo CTPA within the next 24 hours;
• Age \>18 years; no gender restrictions;
• Presence of central venous access (internal jugular or subclavian vein) or peripheral forearm venous access;
• Willingness to participate with signed informed consent from either the patient or legal guardian.

You may not qualify if:

• Pregnancy or lactation;
• Relative contraindications to EIT examination (e.g., chest wall wounds at electrode belt placement site, presence of pacemakers);
• Severe hypernatremia (serum sodium \>155 mmol/L);
• Inability to maintain expiratory breath-hold for ≥8 seconds;
• BMI \>50 or severe thoracic deformities;
• Current extracorporeal membrane oxygenation (ECMO) therapy.

Sponsors & Collaborators

• Peking Union Medical College Hospital: lead

Study Sites (1)

Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences

Beijing, Beijing Municipality, 100730, China

RECRUITING

Central Study Contacts

Huaiwu He

CONTACT

01069152301; tjmuhhw@163.com

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 14, 2025
• First Posted: September 24, 2025
• Study Start: September 24, 2025
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): September 15, 2027
• Last Updated: October 2, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)