CARDIAC-OUTPUT MEASUREMENT BY TRANSPULMONARY VERSUS CONVENTIONAL THERMODILUTION TECHNIQUE IN INTENSIVE-CARE PATIENTS AFTER CORONARY-ARTERY BYPASS-GRAFTING

Objective: The aim of the present study was to evaluate the correlatio n, accuracy, and precision of transpulmonary thermodilution cardiac ou tput (CO) measurement. For this purpose, this technique was compared w ith the clinical gold standard, the CO measurement by pulmonary artery catheter in patients after coronary artery bypass grafting (CABG). De sign: A prospective clinical study. Setting: A university medical cent er. Participants: Seventy-five patients in an intensive care unit (ICU ) after CABG. Interventions: Standard (SCO) and transpulmonary thermod ilution CO measurement (TPCO) measurements were simultaneously perform ed in triplicate by central venous injection of cooled saline solution . AII variables were recorded at five different time points of measure ment during weaning from mechanical ventilation. Measurements and Main Results: CO measurements yielded 375 data pairs. SCO ranged from 2.0 to 10.2 L/min, and TPCO from 1.3 to 10.6 L/min. During the entire obse rvation period, TPCO measurements tended to yield relatively high valu es, whereas SCO measurements resulted in lower values. Correlation bet ween TPCO and SCO measurements was significant (r = 0.73; p < 0.05), a ccompanied by an accuracy with a bias of 0.456 L/min (7.3%) and a prec ision of 1.156 L/min (18.5%). Conclusion: In most patients, TPCO measu rement will not replace the conventional technique by pulmonary artery catheter, but in some patients it offers an attractive, reliable, and safe method to determine CO. Copyright (C) 1998 by W.B. Saunders Comp any.