Hemodynamic effects of passive leg raising: an echocardiographic study in patients with shock
- 411 Downloads
To determine the effects of passive leg raising (PLR) on hemodynamics and on cardiac function according to the preload dependency defined by the superior vena cava collapsibility index (ΔSVC).
Forty patients with shock, sedated and mechanically ventilated, were included. Transesophageal echocardiography was performed. At baseline (T1), two groups were defined according to ΔSVC. Eighteen patients presenting a ΔSVC > 36%, an indicator of preload dependency, formed group 1, whereas 22 patients (group 2) exhibited a ΔSVC < 30% (not preload-dependent). Measurements were then performed during PLR (T2), back to baseline (T3), and after volume expansion (T4) in group 1 only. At T1, ΔSVC was significantly higher in group 1 than in group 2, 50 ± 9% and 7 ± 6%, respectively. In group 1, we found a decrease in ΔSVC at T2 (24 ± 9%) and T4 (17 ± 7%), associated with increased systolic, diastolic and arterial pulse pressures. Cardiac index also increased, from 1.92 ± 0.74 (T1) to 2.35 ± 0.92 (T2) and 2.85 ± 1.2 l/min/m2 (T4) and left ventricular end-diastolic volume from 51 ± 41 to 61 ± 51 and 73 ± 51 ml/m2. None of these variations was found in group 2. No change in heart rate was observed.
Hemodynamic changes related to PLR were only induced by increased cardiac preload.
KeywordsFluid responsiveness Passive leg raising Superior vena cava Transesophageal echocardiography Shock Cardiac preload
- 11.Parati G, Grassi G, Coruzzi P, Musiari L, Ravogli A, Novarini A, Mancia G (1987) Influence of cardiopulmonary receptors on the bradycardic responses to carotid baroreceptor stimulation in man. Clin Sci (Lond) 72:639–645Google Scholar
- 19.Schiller NB, Shah PM, Crawford M, DeMaria A, Devereux R, Feigenbaum H, Gutgesell H, Reichek N, Sahn D, Schnittger I (1989) Recommendations for quantitation of the left ventricle by two-dimensional echocardiography. American Society of Echocardiography Committee on Standards, Subcommittee on Quantitation of Two-Dimensional Echocardiograms. J Am Soc Echocardiogr 2:358–367PubMedGoogle Scholar
- 21.Weyman A (1982) Cross-Sectional echocardiography. In: Lea & Febiger (ed), Philadelphia PA, pp 501–502Google Scholar
- 22.Starling EH (1965) The Linacre Lecture of the Law of the Heart. In: Chapman CB, Mitchell JH (ed) Starling on the heart. Dawsons, London, pp 119–147Google Scholar
- 30.Pawelczyck JA, Levine BD (1995) Cardiovascular responses to rapid volume infusion: the human Bainbridge reflex. Circulation 92:3148Google Scholar