Evaluating Superior Vena Cava Variations to Predict Fluid Needs in Shock Patients

Association of Respiratory Variation of Superior Vena Cava in Transthoracic View and Fluid Responsiveness in Critically Ill Patients

Observational University of Chile · NCT05211765

This study is testing if changes in a specific vein's size can help doctors decide how much fluid critically ill patients in the ICU need to get better.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Chile Academic / other
Locations1 site (Santiago, Región Metropolitana)
Trial IDNCT05211765 on ClinicalTrials.gov

What this trial studies

This observational study aims to assess the respiratory variations in the diameter of the superior vena cava using transthoracic echocardiography to predict fluid responsiveness in critically ill patients. The study focuses on patients in the Intensive Care Unit who are under positive pressure ventilation and exhibit hemodynamic instability. By identifying fluid responsiveness predictors, the study seeks to improve fluid management and avoid the negative outcomes associated with excessive fluid administration. The hypothesis is that variations in the superior vena cava diameter can effectively indicate whether a patient will benefit from fluid administration.

Who should consider this trial

Good fit: Ideal candidates include adults over 18 years old, hospitalized in the ICU, under positive pressure ventilation, and exhibiting hemodynamic instability.

Not a fit: Patients with spontaneous ventilatory effort or those who cannot undergo the necessary echocardiographic evaluation may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to more accurate fluid management in critically ill patients, potentially improving patient outcomes.

How similar studies have performed: While the approach of using echocardiographic measurements for fluid responsiveness is established, the specific use of transthoracic evaluation of the superior vena cava is relatively novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients \>18 years,
* Hospitalized in the Intensive Care Unit (ICU) with length of stay under 7 days
* Under positive pressure ventilation with no inspiratory effort,
* With hemodynamic instability (defined as abnormal peripheral perfusion or increased blood lactic or vasopressor infusion of norepinephrine \>0.1 ug/kg/min to achieve adequate mean arterial pressure)

Exclusion Criteria:

* Spontaneous ventilatory effort
* Lack of venous access
* Carrier of carbapenemase or clostridium difficile
* Lack of adequate superior vena cava (SVC) window (not allowing M-mode during both respiratory phases)
* Severe aortic regurgitation
* Impossibility to measure LVOT-VTI
* Extracorporeal membrane oxygenation.

Where this trial is running

Santiago, Región Metropolitana

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Shock
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.