Initialization of Pulse Transit Time-Based Blood Pressure Monitors

Abstract

Pulse transit time (PTT)-based monitors can potentially permit cuffless blood pressure (BP) measurements, but initialization of the monitors so that the measured time delay may be mathematically converted to absolute BP is difficult. The goal of this chapter is to facilitate the achievement of reliable and practical initialization of PTT-based BP monitors. We present parametric models to relate PTT to BP; explain three different methods to determine the model parameters for a patient via cuff BP measurements that range from more accurate to more convenient; describe models that incorporate readily available covariates in addition to PTT and parameter determination methods for these enhanced models; discuss the required time period for reinitialization of the monitors with cuff BP measurements; and make recommendations and provide our outlook on such monitors.