Passive Leg Raise

OVERVIEW

• Passive Leg Raise (PLR) transiently increases venous return in patients who are preload responsive, as such it is a diagnostic test not a treatment
• it is a predictor of Fluid responsiveness (i.e. helps identify patients who are on the ascending portion of their Starling Curve, and will have an increase in stroke volume in response to fluid administration)

TECHNIQUE

• sit patient at 45 degrees head up semi-recumbent position
• lower patient’s upper body to horizontal and passively raise legs at 45 degrees up
• maximal effect occurs at 30-90 seconds
• assess for a 10% increase in stroke volume (cardiac output monitor) or using a surrogate such as pulse pressure (using an arterial line)

PERFORMANCE CHARACTERISTICS

• 9% increase in stroke volume has 86% sensitivity and 90% specificity
• 10% increase in pulse pressure has 79% sensitivity and 85% specificity
• A small yet-to-be-validated study found that a PLR-induced increase in EtCO(2) ≥ 5 % predicted a fluid-induced increase in CI ≥ 15 % with 71% sensitivity (95 %CI = 48-89 %) and 100% specificity (95%CI = 82-100%)

PROS AND CONS

Advantages

• reversible
• non-invasive
• easy to perform in patients breathing spontaneously and with arrhythmias (but must use measures other than stroke volume variation and pulse pressure variation)
• can be repeated many times to reassess preload responsiveness without any risk of inducing pulmonary edema or cor pulmonale in potential nonresponders

Disadvantages

• unreliable in severely hypovolemic patients
  — the blood volume mobilized by leg-raising (which is dependent on total blood volume) could be small and can show minimal to no increase in CO and blood pressure, even in fluid responsive patients
• need to stop any other interventions during the test
• positional changes may be contra-indicated in some patients
• not useful in patients with raised intra-abdominal pressure

References and Links

LITFL

• CCC — Fluid challenge
• CCC — Fluid responsiveness
• CCC — Systolic Pressure Variation

Journal articles

• Monnet X, Bataille A, Magalhaes E, Barrois J, Le Corre M, Gosset C, Guerin L, Richard C, Teboul JL. End-tidal carbon dioxide is better than arterial pressure for predicting volume responsiveness by the passive leg raising test. Intensive Care Med. 2013 Jan;39(1):93-100. PMID: 22990869.
• Monnet X, Bleibtreu A, Ferré A, Dres M, Gharbi R, Richard C, Teboul JL. Passive leg-raising and end-expiratory occlusion tests perform better than pulse pressure variation in patients with low respiratory system compliance. Crit Care Med. 2012 Jan;40(1):152-7. PMID: 21926581.
• Monnet X, Rienzo M, Osman D, Anguel N, Richard C, Pinsky MR, Teboul JL. Passive leg raising predicts fluid responsiveness in the critically ill. Crit Care Med. 2006 May;34(5):1402-7. PMID: 16540963.
• Préau S, Saulnier F, Dewavrin F, Durocher A, Chagnon JL. Passive leg raising is predictive of fluid responsiveness in spontaneously breathing patients with severe sepsis or acute pancreatitis. Crit Care Med. 2010 Mar;38(3):819-25. PMID: 20016380.

FOAM and web resources

• EMCrit Podcast 64 – Fluid Responsiveness with Dr. Paul Marik (2013)
• PulmCCM.org — Passive leg raise offers promise in predicting fluid responsiveness (Chest) (2013)
• Resus.ME — Predicting volume responsiveness
• UMEM Education Pearls — Can your breath, predict fluid responsiveness best?
• UMEM Education Pearls — Passive Leg Raising