Appraisal of the Exactness of a Method to Semiinvasively Evaluate the Cardiac Output of ICU-Patients Through the Use of the Pulsioflex Device

Goal of the Study is to Study the precision of semi-invasive cardiac index monitoring by means of the ProAQT (PULSION Medical Systems SE) sensor, whereby the pulmonary artery catheter will serve as gold standard.

Measurements will be performed contemporaly with both devices every 4 hours and all clinical and hemodynmaic parameters will be recorded, including but not limited to central venous pressure, wege pressure, mechanical ventilation pressures, blood pressures, volume balance as well as vasoaktive medikation doses. This precise evaluation shall serve to evaluate the precision of the ProAQT to estimate the cardiac index under different clinical situation in the intensive care unit. A precision difference of below 30% between both methods will be regarded as clinically irrelevant, suggesting equipoise between both methods.