Point of care transthoracic echocardiography for the prediction of post – spinal anesthesia hypotension in elderly patients with cardiac diseases and left ventricular dysfunction

Abstract

In elderly patients with cardiac diseases, changes in cardiovascular physiology diminish cardiovascular reserve and predispose to hemodynamic instability after spinal anesthesia; hence, such patients could be at risk of postoperative complications. Additionally, transthoracic echocardiography (TTE) is used in clinical practice to evaluate cardiovascular hemodynamics. Therefore, we hypothesized that echocardiographic measurements could display significant diagnostic power in the prediction of post - spinal anesthesia hypotension in elderly patients with cardiac diseases and reduced left ventricular ejection fraction (LV-EF). Therefore, sixty-one elderly orthopedic-trauma patients were recruited. Prior to spinal anesthesia a TTE examination was performed. The LV-EF, the stroke volume index (SVI), the peripheral vascular resistance (PVR), the LV filling pressures (E/Em ratio), the right ventricular function [tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (TASV) and fractional area change (FAC)], as well as inferior vena cava (IVC) measurements, such as IVCCI (collapsibility index of the IVC) and dIVCmax (maximum diameter of IVC)-to-IVCCI ratio were assessed. Twenty-six out of sixty-one patients manifested hypotension. Preoperative dIVCmax-to-IVCCI ratio demonstrated the greatest performance amongst echocardiographic indices in predicting post - spinal anesthesia hypotension. The dIVCmax-to-IVCCI ratio < 48 had significantly higher diagnostic power than IVCCI > 0.28, FAC > 42, E/Em ratio < 9 and SVI < 32 (receiver operator characteristic curve analysis). The gray zone for the dIVCmax-to-IVCCI ratio (40–49) showed the lowest number of inconclusive measurements among echocardiographic variables. The preoperative dIVCmax-to-IVCCI ratio could be a reliable echocardiographic index to predict post - spinal anesthesia hypotension in elderly patients with left ventricular dysfunction.