A Pain Assessment Method Based on a Log-Linearized Peripheral Arterial Viscoelastic Model :

Relationship Between Pain and Arterial Stiffness Change Under Nociceptive Mechanical Stimuli

Abstract

This paper examines a relationship between an arterial stiffness parameter β and nociceptive mechanical stimuli. The stiffness parameter β which reacts according to peripheral sympathetic nerve activity is calculated from continuous arterial pressures and photoplethysmograms based on the log-linearized peripheral arterial viscoelastic model, while mechanical stimuli were applied to the subjects in the experiments. The results showed a significant correlation between the stimulus velocity and the stiffness parameter β when stimulus amplitude was constant (r = 0.63 (p < 0.05)) and that between the stimulus amplitude and the normalized stiffness parameter β_n when stimulus velocity was constant (r = 0.54 (p < 0.01)). It was therefore concluded that the arterial stiffness parameter β may react to amplitude and velocity of mechanical stimuli.