Inferior Vena Cava Versus Subclavian Vein Collapsibility for Predicting Fluid Responsiveness in Trauma Hemorrhagic Shock

September 9, 2026 updated by: Basant Saody Hashem, Assiut University

Comparison of Inferior Vena Cava Versus Subclavian Vein Collapsibility Indices for Prediction of Fluid Responsiveness in Adult Trauma Patients Presenting With Hemorrhagic Shock: A Prospective Comparative Cohort Study

Hemorrhagic shock from severe bleeding is a leading cause of preventable death in trauma patients. Intravenous (IV) fluid resuscitation is essential for stabilizing blood pressure and organ perfusion, but administering too much or too little fluid can cause severe complications. Only about half of hemodynamically unstable patients show an increase in cardiac output after receiving fluids. Emergency physicians often use bedside ultrasound to measure respiratory changes in the inferior vena cava (IVC), known as the IVC collapsibility index (IVC-CI), to predict whether a patient will benefit from fluids. However, obtaining clear IVC views can be difficult or impossible in trauma patients due to abdominal pain, obesity, or abdominal injuries. Evaluating the subclavian vein (SCV) under the collarbone provides a potential alternative window.

The main purpose of this study is to compare the diagnostic accuracy of the subclavian vein collapsibility index (SCV-CI) against the inferior vena cava collapsibility index (IVC-CI) for predicting fluid responsiveness in adult trauma patients presenting with hemorrhagic shock.

Eligible adult trauma patients with hemorrhagic shock will undergo rapid bedside point-of-care ultrasound upon presentation to the emergency department. Physicians will measure respiratory diameter variations in both the subclavian vein and inferior vena cava. Patients will then receive a standardized fluid challenge of 10 mL/kg intravenous balanced crystalloid solution over 10 to 15 minutes as part of resuscitation. Fluid responsiveness will be assessed by measuring changes in blood flow through the neck using carotid artery Doppler ultrasound before and 5 to 10 minutes after the fluid challenge. The study will determine whether subclavian vein ultrasound offers comparable diagnostic performance and greater feasibility compared to inferior vena cava ultrasound in emergency trauma resuscitation.

Study Overview

Status

Not yet recruiting

Conditions

Study Type

Observational

Enrollment (Estimated)

120

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
  • Older Adult

Accepts Healthy Volunteers

N/A

Sampling Method

Non-Probability Sample

Study Population

Adult trauma patients aged 18 years or older presenting with blunt or penetrating trauma and clinical evidence of hemorrhagic shock (systolic blood pressure < 90 mmHg, mean arterial pressure < 65 mmHg, or clinical signs of tissue hypoperfusion) to the Emergency Department of Assiut University Trauma and Emergency Hospital within 6 hours of injury.

Description

Inclusion Criteria:

  • Adult patients aged 18 years or older.
  • Presentation with blunt or penetrating trauma.
  • Clinical evidence of hemorrhagic shock, defined by hypotension (systolic blood pressure < 90 mmHg or mean arterial pressure < 65 mmHg), tachycardia, or other clinical signs of tissue hypoperfusion requiring fluid resuscitation.
  • Spontaneously breathing patients.
  • Presentation to the Emergency Department within 6 hours of injury.
  • Feasibility of bedside point-of-care ultrasound examination prior to the initiation of definitive resuscitation.

Exclusion Criteria:

  • Age younger than 18 years.
  • Pregnancy.
  • Requirement for immediate endotracheal intubation and mechanical ventilation prior to ultrasound assessment.
  • Obstructive shock due to cardiac tamponade, tension pneumothorax, or other known causes.
  • Known severe heart failure with left ventricular ejection fraction (LVEF) < 40%.
  • Significant tricuspid regurgitation or known pulmonary hypertension that may affect systemic venous measurements.
  • Major neck or clavicular trauma preventing adequate subclavian vein ultrasound acquisition.
  • Extensive abdominal trauma, morbid obesity, or other conditions precluding adequate inferior vena cava (IVC) acoustic visualization.
  • Transfer from another facility after receiving large-volume fluid resuscitation (> 1 L of crystalloids or blood products prior to assessment).
  • Inability or refusal to provide informed consent by the patient or their legally authorized representative.

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

Cohorts and Interventions

Group / Cohort
Adult Trauma Patients with Hemorrhagic Shock
Spontaneously breathing adult trauma patients (aged ≥ 18 years) presenting to the Emergency Department within 6 hours of blunt or penetrating injury with clinical evidence of hemorrhagic shock (SBP < 90 mmHg or MAP < 65 mmHg, tachycardia, or tissue hypoperfusion). All enrolled participants undergo baseline point-of-care ultrasound examination to measure both the inferior vena cava collapsibility index (IVC-CI) and subclavian vein collapsibility index (SCV-CI), in addition to carotid artery velocity time integral (Carotid VTI). Following baseline ultrasound, participants receive a standardized fluid challenge of 10 mL/kg intravenous balanced crystalloid over 10-15 minutes. Carotid VTI is remeasured within 5-10 minutes post-infusion to evaluate fluid responsiveness (defined as a Carotid VTI increase ≥ 15%).

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Area Under the Receiver Operating Characteristic Curve (AUC) of Subclavian Vein Collapsibility Index (SCV-CI)
Time Frame: 10 minutes post-fluid challenge
The area under the receiver operating characteristic curve (AUC-ROC) will be calculated to determine the diagnostic accuracy of baseline SCV-CI for predicting fluid responsiveness. Fluid responsiveness is defined as an increase of ≥ 15% in carotid artery velocity time integral (Carotid VTI) following a 10 mL/kg crystalloid bolus. AUC values range from 0.5 (no discriminative ability) to 1.0 (perfect diagnostic accuracy).
10 minutes post-fluid challenge

Collaborators and Investigators

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

Sponsor

Assiut University

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)

October 1, 2026

Primary Completion (Estimated)

October 1, 2027

Study Completion (Estimated)

November 1, 2027

Study Registration Dates

First Submitted

September 9, 2026

First Submitted That Met QC Criteria

September 9, 2026

First Posted (Actual)

September 14, 2026

Study Record Updates

Last Update Posted (Actual)

September 14, 2026

Last Update Submitted That Met QC Criteria

September 9, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • IVC vs SCV for Fluid Response

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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