Ultrasound stroke volume variation induced by passive leg raising and fluid responsiveness: An observational cohort study / Variación ultrasónica del volumen sistólico inducida por la elevación pasiva de la pierna y la respuesta de fluidos: estudio de cohortes observacional

Objective: To assess the performance of the ultrasound measurement of stroke volume (SV) coupled to passive leg raising (PLR) in predicting fluid responsiveness (FR). Design: A prospective cohort study was carried out in patients requiring volume expansion (VE). A transthoracic Doppler echocardiography (TTE) device was used for the measurement of SV. Four measurements were obtained: before and 90s after PLR, and before and after VE. The patients were subsequently classified according to their hemodynamic response to VE. Responders were defined by an increase in SV of at least 15% in response to VE. Results: Thirty maneuvers were studied. An increase in SV>15% in response to PLR was recorded in 21 cases. Hemodynamic indices taken in the first stage showed significant differences in the distensibility index of the inferior vena cava (dIVC), in the velocity-time integral of aortic blood flow (VTIAo) and in SV, with respective p-values of 0.009, 0.012 and 0.025. The SV changes induced by VE were significantly correlated to the SV changes induced by PLR, with a Spearman coefficient of 0.77 and a linear equation y=0.82 x+1.68. Fluid responsiveness can be efficiently predicted by assessing the effects of PLR on SV monitored by Doppler TTE, with a sensitivity of 94.7% and a negative predictive value of 88%. Conclusion: Our data support the interest of Doppler TTE as an effective tool in predicting FR through the assessment of SV in response to PLR, in hemodynamically unstable patients

Objetivo: Evaluar el rendimiento de la medida del volumen sistólico (VS) por ultrasonido junto con la elevación pasiva de piernas (EPP) para predecir la respuesta de fluidos (RF). Diseño: Estudio prospectivo de cohorte realizado en pacientes que requieren expansión de volumen (EV). Se utilizó un dispositivo doppler ecocardiográfico transtorácico (ETT) para la medición del VS. Se obtuvieron 4 mediciones: antes y 90s después de la EPP, y antes y después de la EV. Posteriormente, los pacientes se clasificaron según su respuesta hemodinámica a VE. Los respondedores se definieron por un aumento del VS de al menos 15% en respuesta a EV. Resultados: Se estudiaron 30 maniobras. Un aumento del VS>15% en respuesta a la EPP se informó en 21 casos. Los índices hemodinámicos tomados en la primera etapa mostraron diferencias significativas en el índice de distensibilidad de la vena cava inferior (dVCI), en la integral velocidad-tiempo del flujo sanguíneo aórtico (IVTAo) y en el VS con valores p respectivos en 0,009, 0,012 y 0,025. Los cambios del VS inducidos por EV se correlacionaron significativamente con los cambios del VS inducidos por EPP con un coeficiente de Spearman en 0,77 y una ecuación lineal en y=0,82× +1,68. La respuesta de fluidos se puede predecir eficazmente mediante la evaluación de los efectos de EPP en el VS vigilado por ETT-doppler con sensibilidad en el 94,7% y VPN en el 88%. Conclusión: Nuestros datos respaldan el interés del ETT-doppler como una herramienta eficaz en la predicción de la RF por la evaluación del VS en respuesta a la EPP en pacientes hemodinámicamente inestables

Ultrasound stroke volume variation induced by passive leg raising and fluid responsiveness: An observational cohort study.

OBJECTIVE: To assess the performance of the ultrasound measurement of stroke volume (SV) coupled to passive leg raising (PLR) in predicting fluid responsiveness (FR). DESIGN: A prospective cohort study was carried out in patients requiring volume expansion (VE). A transthoracic Doppler echocardiography (TTE) device was used for the measurement of SV. Four measurements were obtained: before and 90s after PLR, and before and after VE. The patients were subsequently classified according to their hemodynamic response to VE. Responders were defined by an increase in SV of at least 15% in response to VE. RESULTS: Thirty maneuvers were studied. An increase in SV>15% in response to PLR was recorded in 21 cases. Hemodynamic indices taken in the first stage showed significant differences in the distensibility index of the inferior vena cava (dIVC), in the velocity-time integral of aortic blood flow (VTIAo) and in SV, with respective p-values of 0.009, 0.012 and 0.025. The SV changes induced by VE were significantly correlated to the SV changes induced by PLR, with a Spearman coefficient of 0.77 and a linear equation y=0.82 x+1.68. Fluid responsiveness can be efficiently predicted by assessing the effects of PLR on SV monitored by Doppler TTE, with a sensitivity of 94.7% and a negative predictive value of 88%. CONCLUSION: Our data support the interest of Doppler TTE as an effective tool in predicting FR through the assessment of SV in response to PLR, in hemodynamically unstable patients.