The relationship between arterial blood pressure and accelerated plethysmogram (APG) obtained by differentiating two times digital plethysmogram was studied in five healthy male university students. Finger arterial blood pressure was found to change by inflating the cuff of a sphygmomanometer placed on the upper arm followed by gradual deflation. APG and blood pressure were analyzed in the beat by beat mode. Room temperature was maintained at 23-24°C.
The following results were obtained :
1) Component“a”of APG became higher, and“b”and“e”components became increased with systolic blood pressure (SBP) .
2) Component“a”of APG decreased, as did also“b”and“e”components with increase in diastolic blood pressure (DBP) and arteriolar elasticity.
3) The two mechanisms for increase in SBP were increase in blood volume, and increase in peripheral resistance. The wave pattern of APG (A-G) changed from G to A by the former, and A to G by the latter.
These findings clearly show the relationship between APG and arterial blood pressure depend on the particular mechanism involved. The simultaneous mesurement of APG and blood pressure may serve as a useful means for measuring peripheral hemodynamics.