A new noninvasive finger sensor (NICCI system) for cardiac output monitoring A method comparison study in patients after cardiac surgery

BACKGROUND The new noninvasive finger sensor system NICCI (Getinge; Gothenburg, Sweden) allows continuous cardiac output monitoring. We aimed to investigate its cardiac output measurement performance. OBJECTIVE(S) To investigate the NICCI system's cardiac output measurement performance. DESIGN Prospective method comparison study. SETTING University Medical Center Hamburg-Eppendorf, Hamburg, Germany. PATIENTS Fifty-one patients after cardiac surgery. MAIN OUTCOME MEASURES We performed a method comparison study in 51 patients after cardiac surgery to compare NICCI cardiac output (CONICCI) and NICCI cardiac output calibrated to pulmonary artery thermodilution cardiac output measurement (CONICCI-CAL) with pulmonary artery thermodilution cardiac output (COPAT). As a secondary analysis we also compared CNAP cardiac output (COCNAP) and externally calibrated CNAP cardiac output (COCNAP-CAL) with COPAT. RESULTS We analysed 299 cardiac output measurement pairs. The mean of the differences (95% limits of agreement) between CONICCI and COPAT was 0.6 (-1.8 to 3.1) l min(-1) with a percentage error of 48%. The mean of the differences between CONICCI-CAL and COPAT was -0.4 (-1.9 to 1.1) l min(-1) with a percentage error of 29%. The mean of the differences between COCNAP and COPAT was 1.0 (-1.8 to 3.8) l min(-1) with a percentage error of 53%. The mean of the differences between COCNAP-CAL and COPAT was -0.2 (-2.0 to 1.6) l min(-1) with a percentage error of 35%. CONCLUSION The agreement between CONICCI and COPAT is not clinically acceptable.