Non-invasive and simultaneous cardiovascular measurements using plethysmography techniques.
New non-invasive multifunctional methods have been proposed for the simultaneous measurements of more than two cardiovascular hemodynamic parameters such as peripheral and central blood flow, arterial and venous pressure, peripheral flow resistance, arterial and venous elasticity, hematocrit, blood oxygenation, etc. A proper combination of one or two of the recently developed sphygmomanometries called the 'volume oscillometric method' and the 'volume compensation method' with photoelectric plethysmography, and blood flowmetry with electrical admittance plethysmography provides successful measurement of these cardiovascular parameters. This paper discusses the measurement principles, including methodologies, and evaluates the accuracy and practicability of each method. Preliminary descriptions of newly designed instruments based on these methods together with a few examples of measured data are also presented. The results obtained show that the proposed non-invasive and simultaneous physiological measurements appear promising for use not only in basic research laboratories, but also in clinical practice including health screening and testing.
Yamakoshi
K
K
Research Institute of Applied Electricity, Hokkaido University, Sapporo, Japan.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D001794:Blood Pressure; D004548:Elasticity; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010991:Plethysmography / Q000379:methods*; D012016:Reference Values; D012039:Regional Blood Flow