Uncalibrated continuous cardiac output measurement in liver transplant patients: LiDCOrapid™ system versus pulmonary artery catheter

Objective The aim of the study was to assess the level of agreement between continuous cardiac output estimated by uncalibrated pulse-power analysis (PulseCO_LiR) and intermittent (ICO) and continuous cardiac output (CCO) obtained using a pulmonary artery catheter (PAC). Design Prospective cohort study. Setting University hospital intensive care unit. Participants Twenty patients after liver transplantation. Intervention Pulmonary artery catheters were placed in all patients, and ICO and CCO were determined using thermodilution. PulseCO_LiR measurements were made using a LiDCOrapid™ (LiDCO Ltd, Cambridge, UK). Measurements and Main Results ICO data were determined after intensive care unit admission and every 8 hours until the 48th postoperative hour. CCO and PulseCO_LiR measurements were recorded simultaneously at these same time intervals as well as hourly. For the 8-hour data set (140 data pairs), the mean bias and percentage errors (PE) were, respectively,-0.10 L/min and 39.2% for ICO versus PulseCO_LiR and 0.79 L/min and 34.6% for CCO versus PulseCO_LiR. For the hourly comparison of CCO versus PulseCO_LiR (980 data pairs), the bias was 0.75 L/min and the PE 37%. To assess the ability to measure change, a 4-quadrant plot was produced for each pair of methods. The performance of PulseCO _LiR was moderate in detecting changes in ICO. Conclusions In conclusion, the uncalibrated PulseCO_Lir method should not be used as a substitute for the thermodilution technique for the monitoring of cardiac output in liver transplant patients.