Comparison of PPV and LVOT VTI During Passive Leg Raising to Predict Fluid Responsiveness

ConditionsHemodynamic Instability Hypovolemia Critical Illness Pulse Pressure Variation

Trial statusNot yet recruiting

Trial phaseNot listed

Trial typeObservational

Biological sexAll

Age18+

SponsorIzmir Katip Celebi University

About this trial

Hemodynamic instability remains one of the leading causes of morbidity and mortality among critically ill patients in intensive care units. One major contributor to this instability is intravascular fluid deficit. Although fluid administration is often preferred as an initial intervention, inaccurate estimation of fluid requirements carries significant risks. Inadequate resuscitation may lead to tissue hypoperfusion and organ dysfunction, whereas excessive fluid loading is associated with pulmonary edema, increased intra-abdominal pressure, multi-organ dysfunction, and increased mortality. Consequently, reliable prediction of fluid responsiveness is considered a critical determinant in modern intensive care management.

The limited reliability of static parameters in predicting fluid responsiveness and the fact that PPV retains its validity only under specific clinical conditions highlight the need for more effective methods. In recent years, hemodynamic changes assessed during the passive leg raising (PLR) maneuver have gained prominence; particularly, left ventricular outflow tract velocity time integral (LVOT VTI)-based cardiac output measurements have been identified as a strong parameter for predicting fluid responsiveness . Moreover, changes in pulse pressure variation (PPV) during PLR have also been reported as a potential predictor; however, the number of studies prospectively comparing PPV variation and LVOT VTI-based cardiac output change within the same patient population remains limited . Therefore, the proposed study aims to fill this gap in the literature and contribute to fluid management in the intensive care setting.

The aim of this study is to compare the performance of PPV variation and LVOT VTI-based cardiac output change after the PLR maneuver in predicting fluid responsiveness among mechanically ventilated critically ill patients, and to determine the diagnostic value of both methods. The findings of the present study are expected to support more reliable decision-making in fluid therapy and provide clinical evidence toward the individualization of fluid management in intensive care practice.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Adult patients aged ≥18 years

Patients admitted to the intensive care unit receiving mechanical ventilation

Presence of suspected intravascular fluid deficit (hypotension, negative fluid balance, or clinical signs of peripheral hypoperfusion)

Patients in sinus rhythm

Disqualifiers

Patients under 18 years of age

Presence of atrial fibrillation or significant arrhythmias such as frequent ventricular or atrial ectopy

Severe right ventricular dysfunction or significant tricuspid regurgitation

Advanced aortic valve disease (severe stenosis or severe regurgitation)

Trial population

The study population consists of adult critically ill patients admitted to the Intensive Care Unit (ICU) who are receiving mechanical ventilation support. Eligible participants are those identified by the intensive care team as having a suspected intravascular fluid deficit, for whom a fluid responsiveness assessment is clinically indicated. The cohort specifically targets patients undergoing the Passive Leg Raising (PLR) maneuver as part of routine standard practice, where invasive arterial monitoring is available to record Pulse Pressure Variation (PPV).

Trial design

Design model

Cohort

Time perspective

Prospective

Treatments tested in this trial

Not listed

Trial groups

48 Participants

are grouped into 2 trial groups

Group A: Fluid Responders

Group B: Fluid Non-Responders

Trial outcomes

Primary outcomes

Change in Pulse Pressure Variation (Delta PPV)

Pulse Pressure Variation (PPV) is recorded via invasive arterial monitoring at baseline (T0, semi-sitting) and during the Passive Leg Raising maneuver (T1).

Time frame