II. Indications
-
Hypotension or shock evaluation
- Predict volume responsiveness (that Hypotension will respond to fluid bolus)
- Reversible fluid challenge
III. Mechanism
- Adult lower extremity veins contain 150-200 ml blood per leg
- Elevation of both legs above the heart provides a transient autologous fluid bolus of 300-400 cc
IV. Technique: Passive Leg Raise (PLR)
- Start with patient in semirecumbent position (sitting up)
- Head of bed elevated 45 degrees and legs flat
- Measure hemodynamic parameters obtained
- See Inferior Vena Cava Ultrasound for Volume Status
- See Stroke Volume Estimation by Bedside Ultrasound
- Obtain Blood Pressure and Heart Rate
- Arterial Line or other non-invasive hemodynamic monitoring parameters as available
- End-Tidal CO2 (EtCO2) may be used in intubated patients
- Reposition patient with both legs elevated
- Head of bed at 0 degrees flat and both legs elevated to 45 degrees
- Wait for 60-90 seconds
- Repeat hemodynamic parameter measurements as above
V. Interpretation
- Significant improvement in hemodynamic parameters following leg elevation suggests volume responsiveness
- Stroke Volume (LVOT VTI) increase of 10-15% with leg raise suggests fluid responsiveness
- End-Tidal CO2 (EtCO2) increase of 2 mmHg or 5% is suggestive of fluid responsiveness in intubated patients
VI. References
- Swaminathan and Mallemat (2026) Passive Leg Raise, EM:Rap, accessed 6/6/2026