Skip to main content
OpenTrials
Recruiting

NCT Number: NCT07190079

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

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.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Acute Pulmonary Embolism

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

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

Beijing, Beijing Municipality, 100730, China

Location status: Recruiting

Location contact

Huaiwu He

CONTACT

[email protected]

01069152301

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 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.

Exclusion criteria

  • 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.

Treatment and study plan

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:

  • 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.
  • Venous Access: (1)Preferred: Central venous catheter (internal jugular or subclavian vein).(2)Alternative: Peripheral forearm vein (preferably the median cubital vein).
  • Contrast Administration:(1)Central venous route: 10 mL of 10% NaCl.(2)Peripheral venous route: 15 mL of 5% NaHCO₃.

Computed Tomography Pulmonary Angiography (CTPA)

Diagnostic Test

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

Primary outcomes

  1. The ability of proportion of dead space ventilation to diagnose PE

    Time frame: Within 24 hours before or after the CTPA examination

    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).

Secondary outcomes

  1. The ability of proportion of V/Q matching to diagnose PE

    Time frame: Within 24 hours before or after the CTPA examination

    Following a saline contrast EIT examination, the participant's pulmonary ventilation and perfusion distributions will be obtained, allowing for the generation of a V-Q map. Using offline EIT data analysis tool, the proportion of lung regions demonstrating both ventilation and perfusion will be calculated, representing the proportion of V/Q matching (%). 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 V/Q matching to diagnose acute pulmonary embolism (PE).

  2. The ability of proportion of shunt to diagnose PE

    Time frame: Within 24 hours before or after the CTPA examination

    Following a saline contrast EIT examination, the participant's pulmonary ventilation and perfusion distributions will be obtained, enabling the generation of a V-Q map. Using offline EIT data analysis tool, the proportion of lung regions exhibiting perfusion without ventilation will be calculated, representing the proportion of shunt (%). 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 shunt to diagnose acute pulmonary embolism (PE).

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

    Time frame: Within 24 hours before or after the CTPA examination

    Following a saline contrast EIT examination, the participant's pulmonary ventilation and perfusion distributions will be obtained, and a V-Q map will be subsequently generated. Using offline EIT data analysis tool, additional indices reflecting pulmonary ventilation and perfusion will be further calculated. 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 other indicators reflecting pulmonary ventilation and perfusion to diagnose acute pulmonary embolism (PE).

Study contacts

Contact information is provided by the study sponsor or research team.

Huaiwu He

CONTACT

[email protected]

01069152301

Sponsors and collaborators

Lead sponsor

Peking Union Medical College Hospital

Other

Registry information

Official study title

A Multicenter Comparative Study of Saline Contrast Electrical Impedance Tomography Method Versus CTPA in the Diagnosis of Acute Pulmonary Embolism

Acronym: ECTPED

Important dates

Study start
2025
Primary completion
2027
Study completion
2027
First posted
Sep 24, 2025
Registry last updated
Oct 2, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.