Change in end-tidal carbon dioxide outperforms other surrogates for change in cardiac output during fluid challenge

摘要

P Background. During fluid challenge, volume expansion (VE)-induced increase in cardiac output (Delta VECO) is seldom measured. Methods. In patients with shock undergoing strictly controlled mechanical ventilation and receiving VE, we assessed minimally invasive surrogates for Delta VECO (by transthoracic echocardiography): fluid-induced increases in end-tidal carbon dioxide (Delta E-VE'(CO2)); pulse (Delta VEPP), systolic (Delta VESBP), and mean systemic blood pressure (Delta VEMBP); and femoral artery Doppler flow (Delta(VE)FemFlow). In the absence of arrhythmia, fluid-induced decrease in heart rate (Delta VEHR) and in pulse pressure respiratory variation (Delta VEPPV) were also evaluated. Areas under the receiver operating characteristic curves (AUC(ROC)s) reflect the ability to identify a response to VE (Delta VECO >= 15%).