Passive Leg Raising in Term Pregnancy on Hemodynamic Monitoring - Validating With Transthoracic ECHO (LG-ECHO) ((LG-ECHO))

January 27, 2026 updated by: Ayse Zeynep Turan Civraz

Transthoracic Echocardiography as the Reference for Validating Non-invasive Hemodynamic Monitoring During Passive Leg Raising in Term Pregnancy

This prospective observational validation study aims to evaluate the agreement and diagnostic accuracy of ClearSight™ compared with transthoracic echocardiography (TTE) during PLR in term pregnant women.

The ultimate goal is to determine whether ClearSight™ can reliably identify preload responsiveness in term pregnant women compared with the echocardiographic gold standard. The clinical implication is that, if validated, ClearSight™ may reduce unnecessary or harmful fluid administration by accurately detecting preload reserve, and improve maternal safety in peripartum care by providing obstetric anesthesiologists with reliable bedside monitoring tools.

Study Overview

Status

Withdrawn

Conditions

Intervention / Treatment

Detailed Description

Background Pregnancy is characterized by profound hemodynamic changes, which complicate perioperative monitoring and fluid therapy. Non-invasive cardiac output monitoring device, ClearSight™ system, provides continuous stroke volume estimates, but their reliability in pregnant women remains uncertain. Passive leg raising (PLR) is a reversible preload test that can elucidate fluid responsiveness without fluid administration. To date, no study has simultaneously validated ClearSight™ against echocardiographic reference standards during PLR in term pregnant women.

Methods This is a prospective, single-centre, method-comparison and diagnostic accuracy study in term pregnant women (≥37 weeks). Simultaneous ClearSight™ and transthoracic echocardiography (TTE) measurements will be obtained at baseline, during PLR, and during recovery. The primary outcome is agreement between ClearSight™-derived stroke volume index (SVI) changes and TTE-derived Left Ventricular Outflow Tract - Velocity Time Integral (LVOT-VTI) changes during PLR. Secondary outcomes include trending ability and diagnostic accuracy of ClearSight™ Δ%SVI for detecting PLR responders. Four-quadrant and polar plot analyses are the parameters for advanced hemodynamic monitoring methods used in echocardiography to assess fluid responsiveness and cardiac output (CO) trending Sample size: 60 participants, providing at least 180 paired observations.

Conclusions This study will establish whether ClearSight™ can reliably detect preload responsiveness in term pregnant women. Findings could support safer, real-time, non-invasive hemodynamic management during obstetric anaesthesia and maternal critical care.

Study Type

Observational

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

United States
- Florida
  - Jacksonville, Florida, United States, 32209
    - UF Health Jacksonville (Shands Hospital)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Patients will be enrolled when they come to the OB clinic for evaluation and the consents will be obtained. Patients are instructed during consent to abstain from caffeine/nicotine (≥4h) and heavy meals (≥6h). This is feasible as women are already required to fast preoperatively.

Description

Inclusion Criteria:

Term pregnant patients
Singleton pregnancy at ≥37+0 weeks of gestation.
Maternal age between 18 and 45 years.
Hemodynamically stable and in sinus rhythm.
Ability to provide verbal and written informed consent.

Exclusion Criteria:

Hypertensive disorders of pregnancy, significant valvular or congenital heart disease, cardiomyopathy, or persistent arrhythmias.
Multiple gestation (i.e., Twin pregnancy and above)
Endocrine or hematologic conditions likely to affect hemodynamics, including diabetes with or without autonomic neuropathy, thyroid storm, or severe anemia (hemoglobin <8 g/dL).
Active labor with pain or current infusion of uterotonic or vasoactive agents.
Ruptured membranes with frequent contractions or indications for emergent delivery.
Inadequate transthoracic echocardiographic imaging windows at screening.
Emergency or STAT (statim) Cesarean Deliveries

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Agreement between ClearSight™-derived stroke volume index (SVI) changes and TTE-derived Left Ventricular Outflow Tract - Velocity Time Integral (LVOT-VTI) changes during PLR. Time Frame: During PLR	The primary outcome is agreement between ClearSight™-derived stroke volume index (SVI) changes and TTE-derived Left Ventricular Outflow Tract - Velocity Time Integral (LVOT-VTI) changes during PLR.	During PLR

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Trending ability and diagnostic accuracy of ClearSight™ Δ%SVI for detecting PLR responders Time Frame: During PLR	Trending ability and diagnostic accuracy of ClearSight™ Δ%SVI for detecting PLR responders	During PLR

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Ayse Zeynep Turan Civraz

Investigators

Principal Investigator: Ayten Saracoglu, Prof. MD, University of Florida

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

January 1, 2026

Primary Completion (Estimated)

May 30, 2026

Study Completion (Estimated)

July 30, 2026

Study Registration Dates

First Submitted

November 19, 2025

First Submitted That Met QC Criteria