Finger Plethysmography to Predict Fluid Responsiveness in Healthy Pregnancy and Severe Preeclampsia

Finger Plethysmographic Cardiac Output Monitoring to Predict Fluid Responsiveness in Healthy Pregnancy and Women Diagnosed With Preeclampsia and Severe Features

The goal of this observational study is to determine whether noninvasive finger plethysmographic cardiac output monitoring can help predict fluid responsiveness in pregnant women, including those with preeclampsia with severe features.

The main questions it aims to answer are :

• Can changes in cardiac output measured by finger plethysmography predict fluid responsiveness?
• How does this method perform compared with standard echocardiographic assessment? Participants will provide consent and undergo noninvasive hemodynamic monitoring and a brief reversible physiological challenge.

Study Overview

• Status: Not yet recruiting
• Conditions: Pregnancy; Pre-Eclampsia, Severe
• Intervention / Treatment: Diagnostic test: Noninvasive finger plethysmographic cardiac output monitoring; Diagnostic test: Standard transthoracic echocardiographic assessment

• Study Type: Observational
• Enrollment (Estimated): 88

Contacts and Locations

• Study Contact: Name: Study Team; Phone Number: (650) 723-5403; Email: cortner@stanford.edu

Study Locations

• United States
  • California
    • Palo Alto, California, United States, 94304
      • Lucile Packard Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

The study will recruit pregnant people presenting to participating hospital. Two cohorts will be enrolled: healthy pregnant volunteers at term (without hypertensive disorders) and women with a clinical diagnosis of pre-eclampsia with severe features.

Description

Inclusion Criteria:

• Women diagnosed with preeclampsia with severe features following ACOG recommendations (systolic/diastolic BP >160/110 mmHg, proteinuria, or other severe features like headaches, visual disturbances, kidney/liver impairment, thrombocytopenia).
• Healthy pregnant women at term (for comparison group, e.g., scheduled for elective Cesarean delivery).

Exclusion Criteria:

• Patients who can not provide written consent to participate in the study
• BMI greater than 40 kg/m²
• Multiple pregnancy (twins, triplets, etc.)
• Non-reassuring fetal heart tracing
• ≤ 22 weeks gestation
• History of chronic arterial hypertension
• Chronic kidney disease
• Congenital or known acquired heart disease
• Chronic obstructive pulmonary disease
• Diabetes
• History of stroke
• Not tolerating passive leg raising (unable to be placed in the required study position)
• No TTE-windows
• Withdrawing consent
• Emergency cesarean delivery

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy pregnant women; Pregnant participants without hypertensive disorders enrolled for brief, noninvasive hemodynamic assessments	Diagnostic test: Noninvasive finger plethysmographic cardiac output monitoring; Noninvasive hemodynamic monitoring used to assess changes in cardiac output for prediction of fluid responsiveneness; Diagnostic test: Standard transthoracic echocardiographic assessment; Noninvasive hemodynamic monitoring (echocardiography) used to assess changes in cardiac output for prediction of fluid responsiveness
Preeclampsia With Severe Features; Women diagnosed with preeclampsia with severe features enrolled for brief, noninvasive hemodynamic assessments	Diagnostic test: Noninvasive finger plethysmographic cardiac output monitoring; Noninvasive hemodynamic monitoring used to assess changes in cardiac output for prediction of fluid responsiveneness; Diagnostic test: Standard transthoracic echocardiographic assessment; Noninvasive hemodynamic monitoring (echocardiography) used to assess changes in cardiac output for prediction of fluid responsiveness

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prediction Accuracy for Change in Cardiac Output for Fluid Responsiveness	Prediction accuracy (ROC-AUC) of percent change in cardiac output measured by noninvasive finger plethysmographic device during passive leg raising to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent) and 1 minute after passive leg raising

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prediction Accuracy for Change in Pulsatility Index for Fluid Responsiveness	Prediction accuracy (ROC-AUC) of percent change in pulsatility index measured by noninvasive finger plethysmographic device during passive leg raising to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent) and 1 minute after passive leg raising
Prediction Accuracy for Change in Stroke Volume for Fluid Responsiveness	Prediction accuracy (ROC-AUC) of percent change in stroke volume measured by noninvasive finger plethysmographic device during passive leg raising to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent) and 1 minute after passive leg raising
Prediction accuracy for Pulsatility Index at Baseline	Prediction accuracy (ROC-AUC) of baseline pulsatility index measured by noninvasive finger plethysmographic device to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent)
Prediction accuracy for Stroke Volume at Baseline	Prediction accuracy (ROC-AUC) of baseline stroke volume measured by noninvasive finger plethysmographic device to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent)
Prediction accuracy for Cardiac Output at Baseline	Prediction accuracy (ROC-AUC) of baseline cardiac output measured by noninvasive finger plethysmographic device to identify fluid responsiveness (TTE reference)	Baseline (semi-recumbent)
Optimal Diagnostic Cut-Off and Operating Characteristics for Device Parameters	Determination of optimal cut-off values and corresponding sensitivity, specificity, positive predictive value and negative predictive value for noninvasive finger plethysmographic device (TTE reference)	Baseline (semi-recumbent) and 1 minute after passive leg raising
Inter-observer and Intra-observer Variability for Measurements	Inter-observer and intra-observer variability metrics for noninvasive finger plethysmographic device and for TTE.	Baseline (semi-recumbent) and 1 minute after passive leg raising

Collaborators and Investigators

• Sponsor: Stanford University

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): July 1, 2028
• Study Completion (Estimated): July 1, 2028

Study Registration Dates

• First Submitted: February 18, 2026
• First Submitted That Met QC Criteria: February 18, 2026
• First Posted (Actual): February 24, 2026

Study Record Updates

• Last Update Posted (Actual): February 24, 2026
• Last Update Submitted That Met QC Criteria: February 18, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Fluid responsiveness
• Additional Relevant MeSH Terms: Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Pregnancy Complications; Hypertension, Pregnancy-Induced; Pre-Eclampsia
• Other Study ID Numbers: IRB-84875

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No