抄録
Purpose ; The thoracic bioimpedance method (TBI) is thought to be useful to measure cardiac output continuously and non-invasively. In this study, the usefulness of TBI using BioZ.comTM (CardioDynamics International Corp.) in cardiac surgery was examined in comparison with continuous thermodilution methods (CCO) using VigilanceTM (Edwards Lifesciences LLC).
Methods; Cardiac output was continuously measured by both TBI and CCO in 10 patients (ASA risk II) undergoing elective coronary artery bypass grafting. Data were collected (1) after intubation but before incision; (2) after surgery; and (3)12hrs after surgery, when hemodynamics were stable.
Results; Cardiac output measured by TBI and CCO were ranging (1) 1.7to 2.3l·min-1·kg-1 and 1.0 to 2.7 l·min-1·kg-1, (2) 1.1 to 3.1l·min-1·kg-1 and 1.9 to 4.0l·min-1·kg-1, (3) 1.7 to 3.1l·min-1·kg-1 and 2.3 to 3.9l·min-1·kg-1, respectively. And, correlations between cardiac output measured by TBI (Y) and CCO (X) were (1)y=0.891+0.408x;r=0.366, (2) y=0.771+0.478x;r=0.559, and (3)y=0.592+1. 057x;r=0.573.
Conclusions; In cardiac surgery, TBI might be useless to measure cardiac output because it did not have a good correlation with CCO.
