Comparison of a New Semi-invasive Monitoring System With Transpulmonary Thermodilution in Cardiac Surgery Patients
Comparison of a New Semi-invasive Monitoring System With Transpulmonary Thermodilution in Cardiac Surgery Patients
The aim of the study is to investigate the accuracy of a new semi-invasive cardiac output
 monitoring system in patients undergoing elective cardiac surgery. The investigators
 hypothesize that the semi-invasive device may be affected by mean arterial pressure and
 systemic vascular resistance.
A recently introduced semi-invasive monitoring system consists of an algorithm that provides
 beat-to-beat measurement of CI by analysis of the arterial blood pressure tracing. By using
 the autocalibration mode this software calculates the individual aortic compliance and
 systemic vascular resistance by taking patient data like age, height, weight and gender into
 account. After estimation of beat-to-beat stroke volume, a subsequent multiplication by the
 heart rate delivers pulse contour cardiac index. Furthermore, this device offers the
 opportunity for external calibration by a reference technique, e.g. pulmonary or
 transpulmonary thermodilution.

 The aim of the present study was to investigate the accuracy and trending ability of
 autocalibrated semi-invasive CI by a new arterial waveform analysis compared with
 transpulmonary thermodilution before and after cardiopulmonary bypass (CPB).
Inclusion Criteria:

 Patients undergoing elective coronary artery bypass grafting Personal declaration of
 consent to the study

 Exclusion Criteria:

 Patients <18 years of age A left ventricular ejection fraction ≤0.5 Emergency procedures
 Patients with haemodynamic instability requiring continuous pharmacologic support Patients
 with intracardiac shunts Severe aortic-, tricuspid- or mitral stenosis or insufficiency
 Mechanical circulatory support.