2010/03/16 by Kenneth S. Dyson, J. Kevin Shoemaker, Philippe Arbeille +1
paper · doi:10.1113/expphysiol.2009.050815
We compared Modelflow (MF) estimates of cardiac stroke volume (SV) from the finger pressure‐pulse waveform (Finometer ® ) with pulsed Doppler ultrasound (DU) of the ascending aorta during acute changes in total peripheral resistance (TPR) in the supine and head‐up‐tilt (HUT) postures. Twenty‐four women were tested during intravenous infusion of 0.005 or 0.01 μg kg −1 min −1 isoprenaline, 10 or 50 ng kg −1 min −1 noradrenaline and 0.3 mg sublingual nitroglycerine. Responses to static hand‐grip exercise (SHG), graded lower body negative pressure (LBNP, from −20 to −45 mmHg) and 45 deg HUT were evaluated on separate days. Bland–Altman analysis indicated that SV MF yielded lower estimates than SV DU during infusion of 0.01 μg kg −1 min −1 isoprenaline (SV MF 92.7 ± 15.5 versus SV DU 104.3 ± 22.9 ml, P = 0.03) and SHG (SV MF 78.8 ± 12.0 versus SV DU 106.1 ± 28.5 ml, P MF during −45 mmHg LBNP (SV MF 52.6 ± 10.7 versus SV DU 46.2 ± 14.5 ml, P = 0.04) and HUT (SV MF 59.3 ± 13.6 versus SV DU 45.2 ± 11.3 ml, P r 2 = 0.41, P P = 0.46). These results revealed a discrepancy in MF estimates of SV, in comparison with those measured by DU, during acute changes in TPR.