TY - JOUR
T1 - Comparison of dynamic measurements of pulse contour with pulsed heat continuous cardiac output in postoperative cardiac surgical patients
AU - Boyle, Martin
AU - Lawrence, John
AU - Belessis, Andrew
AU - Murgo, Margherita
AU - Shehabi, Yahya
PY - 2007/2/1
Y1 - 2007/2/1
N2 - Cardiac output (CO) can be measured using bolus thermodilution via a pulmonary artery catheter (PAC) and as continuous cardiac output (CCO), using pulsed heat thermodilution. Pulse contour cardiac output (PCCO) measures continuous CO by analysis of the arterial waveform after calibration with thermodilution CO. The Pulsion Medical Systems (PiCCO system) achieves this by transpulmonary aortic thermodilution (TDtpa). There is uncertainty regarding the agreement between TDtpa, CCO, and PCCO CO measurements in situations of rapid haemodynamic changes. We studied the agreement of the measures by comparing digital recordings of cardiac index (CI) determined by PCCO and CCO (PCCI and CCI, respectively) made during periods of haemodynamic instability. After ethics committee approval we studied four post-coronary artery bypass graft patients, in the immediate postoperative period. Each patient had a 7.5F CCO catheter (Edwards Lifesciences) and a 5F, 20 cm PCCO femoral artery catheter. Digital recordings were obtained for the first 12-18 postoperative hours. Six epochs of instability were identified in the first two to three postoperative hours, and at the commencement of inotropic or vasoactive drugs. Notable features, despite frequent PCCO calibrations, were the marked difference of PCCI compared to CCI. In contradistinction, they tracked very closely during a period of stability. Limitations of both methods were noted. Whilst PCCO responded to rapid change, it developed significant error during haemodynmamic instability and requires frequent recalibration. CCO on the other hand has a considerable time lag in responding to changes in CO. The way a monitor measures CO must be taken into account when using the data in clinical management.
AB - Cardiac output (CO) can be measured using bolus thermodilution via a pulmonary artery catheter (PAC) and as continuous cardiac output (CCO), using pulsed heat thermodilution. Pulse contour cardiac output (PCCO) measures continuous CO by analysis of the arterial waveform after calibration with thermodilution CO. The Pulsion Medical Systems (PiCCO system) achieves this by transpulmonary aortic thermodilution (TDtpa). There is uncertainty regarding the agreement between TDtpa, CCO, and PCCO CO measurements in situations of rapid haemodynamic changes. We studied the agreement of the measures by comparing digital recordings of cardiac index (CI) determined by PCCO and CCO (PCCI and CCI, respectively) made during periods of haemodynamic instability. After ethics committee approval we studied four post-coronary artery bypass graft patients, in the immediate postoperative period. Each patient had a 7.5F CCO catheter (Edwards Lifesciences) and a 5F, 20 cm PCCO femoral artery catheter. Digital recordings were obtained for the first 12-18 postoperative hours. Six epochs of instability were identified in the first two to three postoperative hours, and at the commencement of inotropic or vasoactive drugs. Notable features, despite frequent PCCO calibrations, were the marked difference of PCCI compared to CCI. In contradistinction, they tracked very closely during a period of stability. Limitations of both methods were noted. Whilst PCCO responded to rapid change, it developed significant error during haemodynmamic instability and requires frequent recalibration. CCO on the other hand has a considerable time lag in responding to changes in CO. The way a monitor measures CO must be taken into account when using the data in clinical management.
KW - Cardiac index
KW - Cardiac output
KW - Cardiac surgery
KW - Continuous cardiac output
KW - Measurement techniques
KW - Pulse contour cardiac output
UR - http://www.scopus.com/inward/record.url?scp=34247180581&partnerID=8YFLogxK
U2 - 10.1016/j.aucc.2006.11.003
DO - 10.1016/j.aucc.2006.11.003
M3 - Article
C2 - 17424793
AN - SCOPUS:34247180581
SN - 1036-7314
VL - 20
SP - 27
EP - 32
JO - Australian Critical Care
JF - Australian Critical Care
IS - 1
ER -