Comparison of cardiac output measured by pulseCO and that by vigilance during inferior vena cava clamping

BACKGROUND: PulseCO is a low invasive apparatus to measure cardiac output continuously from arterial pulse waveform (PulseCCO). It is thought that the accuracy of PulseCCO measurement is clinically acceptable with stable hemodynamics. We measured and evaluated PulseCCO during inferior vena cava clamp (IVC clamp). METHODS: Anesthesia was induced with propofol and vecuronium. After induction, an arterial catheter and a pulmonary artery catheter were inserted, and anesthesia was maintained with general anesthesia and continuous epidural anesthesia. At first IVC was clamped for five minutes and after an interval of five minutes IVC was clamped again. During IVC clamp maneuver, we measured PulseCCO and continuous cardiac output with Vigilance (VigilanceCCO). RESULTS: At the time of the first IVC clamp and declamp, VigilanceCCO was unchanged, but Pulse CCO showed a marked change. After the second IVC clamp, both PulseCCO and VigilanceCCO decreased, but the change was slower with VigilanceCCO. CONCLUSIONS: With IVC clamp maneuver which is thought to cause rapid change of cardiac output, PulseCCO showed more rapid change in comparison with VigilanceCCO. In the state where hemodynamics change rapidly, PulseCO can be a more useful monitor.