Measurement of cardiac output during exercise in healthy, trained humans using lithium dilution and pulse contour analysis

作者：Elliott Adrian D^*; Skowno Justin; Prabhu Mahesh; Ansley Les

来源：Physiological Measurement, 2012, 33(10): 1691-1701.

DOI：10.1088/0967-3334/33/10/1691

• indicator dilution
• stroke volume
• haemodynamics
• arterial pressure waveform

The aim of this study was to evaluate the use of pulse contour analysis calibrated with lithium dilution in a single device (LiDCO (TM)) for measurement of cardiac output ((Q) over dot) during exercise in healthy volunteers. We sought to; (a) compare pulse contour analysis (PulseCO) and lithium indicator dilution (LiDCO) for the measurement of (Q) over dot during exercise, and (b) assess the requirement for recalibration of PulseCO with LiDCO during exercise. Ten trained males performed multi-stage cycling exercise at intensities below and above ventilatory threshold before constant load maximal exercise to exhaustion. Uncalibrated PulseCO (Q) over dot ((Q) over dot(raw)) was compared to that calibrated with lithium dilution at baseline ((Q) over dot(baseline)), during submaximal exercise below ((Q) over dot(low)) and above ((Q) over dot(high)) ventilatory threshold, and at each exercise stage individually ((Q) over dot(exercise)). There was a significant difference between (Q) over dot(baseline) and all other calibration methods during exercise, but not at rest. No significant differences were observed between other methods. Closest agreement with (Q) over dot(exercise) was observed for (Q) over dot(high) (bias +/- limits of agreement: 4.8 +/- 30.0%). The difference between (Q) over dot(exercise) and both (Q) over dot(low) and (Q) over dot(raw) was characterized by low bias (4-7%) and wide limits of agreement (%26gt; +/- 40%). Calibration of pulse contour analysis with lithium dilution prior to exercise leads to a systematic overestimation of exercising cardiac output. A single calibration performed during exercise above the ventilatory threshold provided acceptable limits of agreement with an approach incorporating multiple calibrations throughout exercise. Pulse contour analysis may be used for (Q) over dot measurement during exercise providing the system is calibrated during exercise.

• 出版日期2012-10