Effects of extravascular lung water on the measurement of transpulmonary thermodilution cardiac output in acute respiratory distress syndrome patients.
OBJECTIVE
Transpulmonary thermodilution cardiac output is used in calculating aortic impedance for calibrating the pulse-contour analysis and is applied to calculate extravascular lung water (EVLW). Whether pulmonary edema affects the accuracy of transpulmonary thermodilution is controversial. This study aimed to investigate the effects of extravascular lung water index (EVLWI) on the transpulmonary thermodilution measurement in acute respiratory distress syndrome (ARDS).


METHODS
A prospective study.


METHODS
The medical intensive care unit of one medical center.


METHODS
Twenty-four ARDS patients.


METHODS
The continuous pulmonary artery thermodilution cardiac index (CCIpa) and the bolus transpulmonary thermodilution cardiac index (BCItp) data were recorded at baseline and repeated immediately and at 2, 4, and 6 hours after volume expansion with a 500-mL infusion of 10% pentastarch (hydroxyethyl starch 200/0.5) at a rate of 10 mL/kg/h.


RESULTS
A total of 120 paired CI measurements were analyzed. Linear regression analysis showed a close correlation between BCItp and CCIpa (R = 0.87). The mean BCItp was higher than CCIpa, and the Bland-Altman analysis revealed a bias of 0.51 ± 0.78 L/min/m(2). The limits of agreement (2 standard deviations) was 1.66 L/min/m(2) (+2.07 and -1.05 L/min/m(2)), and the percentage error was 31.5%. Levels of EVLWI negatively correlated with the difference between BCItp and CCIpa (R = -0.19).


CONCLUSIONS
In ARDS patients, the agreement between transpulmonary thermodilution and pulmonary artery thermodilution for cardiac output measurement is marginally acceptable. The severity of pulmonary edema expressed as EVLWI weakly and negatively correlates with the difference between BCItp and CCIpa derived from the two techniques.
Huang
Chung-Chi
CC
Division of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan. cch4848@adm.cgmh.org.tw
Kao
Kuo-Chin
KC
Fu
Jui-Ying
JY
Hsieh
Meng-Jer
MJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002302:Cardiac Output / Q000502:physiology*; D015633:Extravascular Lung Water / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011654:Pulmonary Edema / Q000150:complications / Q000503:physiopathology*; D012128:Respiratory Distress Syndrome / Q000150:complications / Q000503:physiopathology*; D013815:Thermodilution / Q000379:methods / Q000592:standards